Anatomy_Gray

Anatomy_Gray. Fig. 8.89 Optic canal and superior orbital fissure. Lacrimal branch of the ophthalmic nerve [V1]Nasociliary branch of ophthalmic nerve [V1]Frontal branch of the ophthalmic nerve [V1]Optic nerveOptic canalInferior ophthalmic veinSuperior ophthalmic veinOphthalmic arteryInferior branch of oculomotor nerve [III]Abducent nerve [VI]Trochlear nerve [IV]Superior branch of oculomotor nerve [III]Superior orbital fissureInferior orbital fissureLateralMedial Fig. 8.90 Periorbita. A. Lateral view. B. Common tendinous ring. Fig. 8.91 Fascial sheath of the eyeball. Fig. 8.92 Check ligaments. A. Anterior view. B. Superior view. Medial rectus muscleMedial rectus muscleLateral rectus muscleLateral rectus muscleInferior rectus muscleInferior oblique muscleMedial check ligamentCheck ligament of medial rectusmuscleCheck ligament of lateral rectus muscleLateral check ligamentSuspensory ligamentSuspensory ligamentSuspensoryligamentFascial sheathFascial sheathPeriosteumPeriorbitaLacrimal sacAB


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Anatomy_Gray. Fig. 8.93 Movements of the eyeball. Fig. 8.94 Axes of the eyeball and orbit. Axis of eyeballAxis of orbitMedial Fig. 8.95 Muscles of the eyeball. A. Superior view. B. Lateral view. C. Coronal magnetic resonance image through the eye. Fig. 8.96 Origins of muscles of the eyeball, coronal view. Superior orbital fissureInferior orbital fissureLacrimal nerveFrontal nerveNasociliary nerveOptic nerveLateral rectusMedial rectusSuperior rectusSuperior obliqueLevator palpebrae superiorisInferior rectusInferior ophthalmic veinOphthalmic arteryInferior division of oculomotor nerve [III]Superior division of oculomotor nerve [III]Abducent nerve [VI]Trochlear nerve [IV]LateralMedial Fig. 8.97 Actions of muscles of the eyeball. A. Action of individual muscles (anatomical action). B. Movement of eye when testing specific muscle (clinical testing).


Anatomy_Gray

Anatomy_Gray. Fig. 8.97 Actions of muscles of the eyeball. A. Action of individual muscles (anatomical action). B. Movement of eye when testing specific muscle (clinical testing). AbductionAdductionElevationDepressionInferiorobliqueSuperiorobliqueSuperiorrectusInferiorrectusLateralrectusMedialrectusMuscle testedDirection to moveeye when testingmuscleSuperior rectusInferior rectusLateral rectusMedial rectusInferior obliqueSuperior obliqueLook laterally and upwardLook laterally and downwardLook laterally Look mediallyLook medially and upwardLook medially and downwardABMedialLateral Fig. 8.98 The “H-test.” Right eyeLateral rectus [VI]Superior rectus [III]Inferior rectus [III]Medial rectus [III]Superior oblique [IV]Inferior oblique [III]1.2.3.4.5.6.Medial rectus [III]Inferior oblique [III]Superior oblique [IV]Lateral rectus [VI]Inferior rectus [III]Superior rectus [III]Left eye142635 Fig. 8.99 Arterial supply to the orbit and eyeball. Fig. 8.100 Venous drainage of the orbit and eyeball.


Anatomy_Gray

Anatomy_Gray. Fig. 8.99 Arterial supply to the orbit and eyeball. Fig. 8.100 Venous drainage of the orbit and eyeball. Fig. 8.101 Innervation of the orbit and eyeball. Lacrimal branch of ophthalmic nerve [V1]Nasociliary branchof ophthalmic nerve [V1]Frontal branch of ophthalmic nerve [V1]Optic nerveOptic canalInferior ophthalmic veinSuperior ophthalmic veinOphthalmic arteryInferior branch of oculomotor nerve [III]Superior branch of oculomotor nerve [III]Abducent nerve [VI]Trochlear nerve [IV]Common tendinous ringLateralMedial Fig. 8.102 Oculomotor nerve [III] and its divisions. Fig. 8.103 Trochlear nerve [IV] in the orbit. Fig. 8.104 Ophthalmic nerve [V1] and its divisions. Fig. 8.105 Relationship of the ophthalmic nerve [V1] and its divisions to the muscles of the eyeball. Fig. 8.106 Course of the nasociliary nerve (from [V1]) in the orbit.


Anatomy_Gray

Anatomy_Gray. Fig. 8.105 Relationship of the ophthalmic nerve [V1] and its divisions to the muscles of the eyeball. Fig. 8.106 Course of the nasociliary nerve (from [V1]) in the orbit. Long ciliary nervesShort ciliary nervesLacrimal glandLacrimal nerve (from [V1])Lateral rectus Ciliary ganglionAbducent nerve[VI]Inferior branch of the oculomotor nerve [III]Superior branch of the oculomotor nerve [III]Medial rectus muscleNasociliary nerve (from [V1])Posterior ethmoidal nerveAnterior ethmoidal nerveInfratrochlear nerveLateral Fig. 8.107 Ciliary ganglion. Fig. 8.108 Eyeball. Fig. 8.109 Ophthalmoscopic view of posterior chamber of the right eye. Fig. 8.110 Ciliary body. Fig. 8.111 Layers of the retina in a healthy eye. A. HD-OCT scan of a healthy eye. B. Schematic indicating the layers of the retina on an HD-OCT scan of a healthy eye. C. Diagram illustrating the layers of the retina. Fig. 8.112 High-definition optical coherence tomography (HD-OCT). A. Diseased eye. B. Healthy eye.


Anatomy_Gray

Anatomy_Gray. Fig. 8.112 High-definition optical coherence tomography (HD-OCT). A. Diseased eye. B. Healthy eye. Fig. 8.113 Right ear. Fig. 8.114 Auricle. Fig. 8.115 Sensory innervation of the auricle. Auriculotemporalbranch of themandibular nerve [V3]Great auricular nerve(C2,C3)Facial nerve [VII]Vagus nerve [X]Lesser occipitalnerve (C2) Fig. 8.116 External acoustic meatus. Fig. 8.117 Middle ear. Fig. 8.118 Tympanic membrane (right ear). A. Diagram. B. Otoscopic view. ABPars flaccidaPosteriormalleolar foldHandle ofmalleusUmboCone of lightAnteriormalleolar foldLateral process(of malleus) Fig. 8.119 Parts of the middle ear. Fig. 8.120 Boundaries of the right middle ear.


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Anatomy_Gray. Fig. 8.119 Parts of the middle ear. Fig. 8.120 Boundaries of the right middle ear. Tegmen tympaniTensor tympani musclePharyngotympanic tubeLesser petrosal nerveBranch from internalcarotid plexusSympathetic plexusInternal carotid arteryChorda tympani nerveTympanic branch of the glossopharyngeal nerve [IX]Internal jugular veinPromontoryRound windowFacial nerve [VII]Chorda tympani nervePyramidal eminenceAditus tomastoid antrumProminence of facial canalProminence of lateral semicircular canalOval window Fig. 8.121 Mastoid antrum and surrounding bone. A. Diagram. B. High-resolution CT scan of left ear (petrous temporal bone). BAditus to mastoid antrumTegmen tympaniEpitympanic recessPharyngotympanic tubeMiddle earMastoid processCochleaMiddle earExternal auditorymeatusMastoid air cellsMastoid air cellsMastoid antrumA Fig. 8.122 Pharyngotympanic tube. Fig. 8.123 Auditory ossicles. A. Malleus. B. Incus. C. Stapes.


Anatomy_Gray

Anatomy_Gray. Fig. 8.122 Pharyngotympanic tube. Fig. 8.123 Auditory ossicles. A. Malleus. B. Incus. C. Stapes. Head of malleusNeck ofmalleusABCAnterior processHandle of malleusLateralprocessIncus articulationShort limbMalleus articulationLong limbBody ofincusBase of stapesAnterior limbHead of stapesPosterior limb Fig. 8.124 Muscles associated with the auditory ossicles (right ear). MalleusIncusPyramidal eminenceTendon ofstapedius muscleFootplate of stapesTympanic membranePharyngotympanic tubeTensor tympani muscle Fig. 8.125 Innervation of the middle ear. Prominence of lateralsemicircular canalTensor tympani musclePromontoryLesser petrosal nervePharyngotympanic tubeBranch from internal carotid plexus(caroticotympanic nerve)Tympanic nerve(from glossopharyngeal nerve [IX])Tympanic plexusRound windowStapesProminence of facial canal Fig. 8.126 Grooves and hiatuses for the greater and lesser petrosal nerves. Fig. 8.127 Location of the internal ear in temporal bone. Fig. 8.128 Internal ear.


Anatomy_Gray

Anatomy_Gray. Fig. 8.126 Grooves and hiatuses for the greater and lesser petrosal nerves. Fig. 8.127 Location of the internal ear in temporal bone. Fig. 8.128 Internal ear. Fig. 8.129 Bony labyrinth. SacculeHelicotremaDura materCochleaCochlear ductScala tympaniScala vestibuliPharyngotympanic tubeRound windowOpening of cochlear canaliculusTympanic membraneVestibuleUtricleAmpullaAnterior semicircular canal and ductVestibular aqueductLateral semicircular canal and ductPosterior semicircular canal and ductStapes in oval window Fig. 8.130 Cochlea. ModiolusScala vestibuliScalatympaniCochlear ductLamina of modiolusCochlear nerveSpiral ganglionHelicotrema Fig. 8.131 Membranous labyrinth. Fig. 8.132 Membranous labyrinth, cross section. Vestibular membraneScala vestibuliModiolusLamina of modiolusScala tympaniBasilar membraneSpiral ligamentSpiral organ Fig. 8.133 A. Facial nerve in the temporal bone. B. Chorda tympani in the temporal bone. Fig. 8.134 Transmission of sound.


Anatomy_Gray

Anatomy_Gray. Fig. 8.133 A. Facial nerve in the temporal bone. B. Chorda tympani in the temporal bone. Fig. 8.134 Transmission of sound. Fig. 8.135 Temporal and infratemporal fossae. Zygomatic archArticular tubercleMandibular fossaGroove for middletemporal arteryRamus of mandibleExternal acousticmeatusSupramastoid crestTemporal fossaInfratemporal fossaMasseter muscle Fig. 8.136 Bony features related to the temporal and infratemporal fossae.


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Anatomy_Gray. Fig. 8.136 Bony features related to the temporal and infratemporal fossae. Greater wingof sphenoid boneFrontal boneFrontal process ofzygomatic boneZygomaticofacialforamenZygomaticotemporalforamen(on deep surface ofzygomatic bone)Posterior surfaceof maxillaZygomatic boneMaxillary process ofzygomatic boneLateral plate of pterygoidprocess of sphenoid bonePalatine bonePterygopalatinefossaTympanomastoidfissureMastoid processTympanic plateSpine of sphenoidStyloid processPterygomaxillary fissure(leading into pterygopalatine fossa)PterygoidhamulusExternal acousticmeatusSupramastoid crestGroove for middletemporal arteryMandibular fossaArticular tubercleForamen spinosumInfratemporal crestForamen ovaleInfratemporalsurface of maxillaAlveolar foramenPetrotympanic fissureSquamous part oftemporal bone Fig. 8.137 Mandible. A. Lateral view of left side. B. Medial view of left side. Fig. 8.138 Temporomandibular joint. A. Mouth closed. B. Mouth open.


Anatomy_Gray

Anatomy_Gray. Fig. 8.137 Mandible. A. Lateral view of left side. B. Medial view of left side. Fig. 8.138 Temporomandibular joint. A. Mouth closed. B. Mouth open. ABUpper joint cavityArticular discArticular tubercleFibrocartilage onarticular surfaceCapsuleLower joint cavitySynovialmembraneMandibular fossaForward movement of discand mandible at upper jointLateral pterygoidmuscleProtrusionDepressionHinge movementat lower joint Fig. 8.139 Ligaments associated with the temporomandibular joint. Fig. 8.140 Movements of the temporomandibular joint. Protrusion• Lateral pterygoid assisted by medial pterygoidRetraction• Posterior fibers of temporalis, deep part of masseter, and geniohyoid and digastricDepression• Gravity• Digastric, geniohyoid, and mylohyoid musclesElevation• Temporalis, masseter, medial pterygoid Fig. 8.141 Masseter muscle. Fig. 8.142 Temporal fossa. A. Lateral view. B. Lateral view showing the infratemporal fossa. Fig. 8.143 Temporalis muscle. Lateral view.


Anatomy_Gray

Anatomy_Gray. Fig. 8.141 Masseter muscle. Fig. 8.142 Temporal fossa. A. Lateral view. B. Lateral view showing the infratemporal fossa. Fig. 8.143 Temporalis muscle. Lateral view. Fig. 8.144 Nerves and arteries of the temporal fossa. Temporal fasciaZygomaticotemporal nerve(branch of maxillary nerve [V2])Deep temporal arteriesMandibular nerve [V3]Deep temporal nervesZygomaticofacial nerveInfratemporal crestMaxillary artery in infratemporal fossaExternal carotid arterySuperficial temporal arteryMiddle temporal arteryTemporalis muscle Fig. 8.145 Borders of the infratemporal fossa.


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Anatomy_Gray. Fig. 8.145 Borders of the infratemporal fossa. Foramen spinosumInfratemporal crestForamen ovaleTensor veli palatiniLevator veli palatiniAlveolar foramenLateral plate of pterygoid processPterygomaxillary fissure(leading into pterygopalatine fossa)Posterior surface of maxillaPterygopalatine fossaGreater wing of sphenoid boneMasseterMylohyoidHyoglossusMiddle constrictorSuperior constrictorPharynxSpine of sphenoidHead and neck of mandiblePetrotympanic fissurePterygomandibular raphe Fig. 8.146 Medial pterygoid muscle. Foramen spinosumInfratemporal crestForamen ovaleTensor veli palatiniLevator veli palatiniDeep headmedial pterygoidSuperficial headmedial pterygoidSpine of sphenoidPetrotympanic fissureLingulaMandibular canalSphenomandibular ligament Fig. 8.147 Lateral pterygoid muscle. Infratemporal crestUpper head of lateral pterygoidDeep head medial pterygoidSuperficial headmedial pterygoidLower headlateral pterygoidCapsuleArticular discSphenomandibular ligament


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Anatomy_Gray. Infratemporal crestUpper head of lateral pterygoidDeep head medial pterygoidSuperficial headmedial pterygoidLower headlateral pterygoidCapsuleArticular discSphenomandibular ligament Fig. 8.148 Mandibular nerve [V3]—anterior trunk. Meningeal branch and nerve to medial pterygoid. Deep headmedial pterygoidTrigeminal ganglionUpper head lateral pterygoid (cut )Lower head lateral pterygoid (cut )Nerve to medial pterygoidBranch to tensor veli palatiniMeningeal branchPosterior trunkBranch to tensor tympaniAnterior trunkDeep temporal nervesBuccal nerveNerve to lateral pterygoidMasseteric nerve Fig. 8.149 Mandibular nerve [V3]—posterior trunk. A. Lateral view. B. Anterior view. C. Anteromedial view. Petrotympanic fissureChorda tympani nerveLingual nerveAIncisive nerveMental nerveNerve to mylohyoidInferior alveolar nerveAuriculotemporal nerve


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Anatomy_Gray. B. Anterior view. C. Anteromedial view. Petrotympanic fissureChorda tympani nerveLingual nerveAIncisive nerveMental nerveNerve to mylohyoidInferior alveolar nerveAuriculotemporal nerve Medial pterygoidmuscleLingulaLingual nerveMental nerveIncisive nerveInferior alveolar nerveSphenomandibular ligamentChorda tympaniInferior alveolar nerveSphenomandibular ligamentSuperior constrictor muscleSubmandibular ganglionNerve to mylohyoidGreater horns of hyoid boneHyoglossus muscleGenioglossus muscleGeniohyoid muscleLingual nerveTemporalis tendonPterygomandibular raphe (cut )Buccal nerve (branch of anterior trunk)BCFacial nerve [VII]Trigeminal nerve [V]Mandibular nerve [V3] Fig. 8.150 Chorda tympani and lesser petrosal nerves. A. Course after emerging from the skull. B. Course of parasympathetic fibers.


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Anatomy_Gray. Fig. 8.150 Chorda tympani and lesser petrosal nerves. A. Course after emerging from the skull. B. Course of parasympathetic fibers. APetrotympanic fissureChorda tympani nerve from [VII]Lesser petrosal nerve [IX]Lingual nerveOtic ganglion (medial to [V3])TongueLingual nerveSublingual glandMylohyoidSubmandibular glandSubmandibular ganglionPreganglionic parasympathetic fibers from glossopharyngeal nerve [IX]Postganglionic parasympathetic fibers from otic ganglionPreganglionic parasympathetic fibers from facial nerve [VII]Postganglionic parasympathetic fibers from submandibular ganglionAuriculotemporal nerveTop of parotid glandAuriculotemporal nerve


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Anatomy_Gray. Preganglionic parasympathetic fibers from glossopharyngeal nerve [IX]Postganglionic parasympathetic fibers from otic ganglionPreganglionic parasympathetic fibers from facial nerve [VII]Postganglionic parasympathetic fibers from submandibular ganglionTympanic plexusLesser petrosal nerveOtic ganglionChorda tympani (carries taste fromthe anterior 2/3 of the tongue)Sublingual glandSubmandibularglandChorda tympanicarries parasympatheticinnervation to all glandsbelow the oral fissureSubmandibularganglionLingual nerveAuriculotemporal nerveParotid glandTympanic membraneChorda tympaniTympanic nerveInferior ganglionGreater petrosal nerveBGlossopharyngeal nerve [IX]Facial nerve [VII]Mandibular nerve [V3]Maxillary nerve [V2]Ophthalmic nerve [V1]Trigeminal nerve [V] Fig. 8.151 Maxillary artery.


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Anatomy_Gray. Fig. 8.151 Maxillary artery. Branches of middlemeningeal in cranial cavityMiddle meningeal arteryArtery to masseterUpper head oflateral pterygoid (cut )Pterygoid arteryPterygopalatine fossaLower head of lateralpterygoid (cut )Buccal arteryMental arteryInferior alveolar arteryExternal carotidMaxillary arteryAuriculotemporal nerveSuperficial temporal arteryDeep temporal arteries Fig. 8.152 Pterygoid plexus of veins. Maxillary veinEmissary veins(connect with cavernous sinus)Inferior ophthalmic veinDeep facial veinFacial veinInferior alveolar veinSuperficial temporal veinExternal jugular veinInternal jugular veinPosterior auricular veinRetromandibular vein Fig. 8.153 Pterygopalatine fossa. A. Anterolateral view. B. Lateral view. Fig. 8.154 Sphenoid bone. A. Anterior view. B. Posterosuperior view.


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Anatomy_Gray. Fig. 8.153 Pterygopalatine fossa. A. Anterolateral view. B. Lateral view. Fig. 8.154 Sphenoid bone. A. Anterior view. B. Posterosuperior view. AForamen rotundumSurface related topterygopalatine fossaPterygoid canalPalatovaginal grooveBLesser wingGreater wingForamen rotundumPosterior opening of bony part of pterygoid canalPterygoid processPart of pterygoid canal incartilage of foramen lacerumCartilage filling foramen lacerumGreater petrosal nerve of VIIMaxillary nerve [V2]Internal carotid arterySuperior orbital fissure Fig. 8.155 Gateways of the pterygopalatine fossa. Sphenopalatine foramennasal cavityInferior orbital fissurefloor of orbitPterygomaxillary fissureinfratemporal fossaPalatine canalroof of oral cavity (palate)Pterygoid canalcranial cavity(middle cranial fossa)Foramen rotundumcranial cavity(middle cranial fossa)Palatovaginal canalnasopharynx Fig. 8.156 Maxillary nerve [V2]. A. Terminal branches. B. In relationship to the pterygopalatine ganglion.


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Anatomy_Gray. Fig. 8.156 Maxillary nerve [V2]. A. Terminal branches. B. In relationship to the pterygopalatine ganglion. Fig. 8.157 Nerve of the pterygoid canal. A. Overview. B. In relationship to the pterygopalatine ganglion. ABLacrimal nerveLacrimal glandParasympathetic nerves in branch of zygomaticotemporal nerveZygomatic nerveNerve of pterygoid canalCartilage filling foramen lacerumDeep petrosal nerveInternal carotid nerveFacialnerve [VII]Preganglionic sympathetic nerves from T1Superior cervical sympathetic ganglionSympathetic trunkGeniculate ganglionGreater petrosal nerveInternal carotid plexus[V1][V2][V3]Internal carotid arteryPterygopalatine fossaInferior orbital fissureInfra-orbital nervePreganglionic parasympathetic nervesPostganglionic parasympathetic nervesPreganglionic sympathetic nervesPostganglionic sympathetic nervesNerve of pterygoid canal Fig. 8.158 Maxillary artery in the pterygopalatine fossa.


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Anatomy_Gray. Fig. 8.158 Maxillary artery in the pterygopalatine fossa. Pharyngeal arterySphenopalatine arteryInfra-orbital arterySeptal part of greater palatine arteryAnterior superior alveolar arteryPosterior superior alveolar arteryGreater palatine arteryLesser palatine arteryMaxillary artery ininfratemporal fossaNasopharynxArtery of pterygoid canalCartilage filling foramen lacerum Fig. 8.159 Veins of the pterygopalatine fossa. Fig. 8.160 Compartments of the neck. Fig. 8.161 Anterior and posterior triangles of the neck. Inferior border of mandibleAnteriortriangleSternocleidomastoid muscleClavicleTrapezius musclePosteriortriangle Fig. 8.162 Fascia of neck, transverse view. Fig. 8.163 Fascia of the neck, sagittal view. Investing layerInfrahyoid musclesPretracheal fasciaManubrium of sternumPretracheal spaceFascial space within prevertebral layerRetropharyngeal spacePrevertebral layerBuccopharyngeal fascia(posterior portion ofpretracheal layer) Fig. 8.164 Superficial veins of neck.


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Anatomy_Gray. Fig. 8.164 Superficial veins of neck. Fig. 8.165 Placing a central venous catheter in the neck. A. Clinical procedure. B. Chest radiograph showing that the tip of the catheter is in the origin of the right atrium. Fig. 8.166 Borders and subdivisions of the anterior triangle of the neck. Submandibular triangleAnterior belly ofdigastric muscleSubmental triangleHyoid boneSuperior belly of omohyoid muscleMuscular triangleSternocleidomastoid muscleTrapezius musclePosterior triangleCarotid triangleStylohyoid musclePosterior belly of digastric muscle Fig. 8.167 Suprahyoid muscles. A. Lateral view. B. Inferior view. Fig. 8.168 Infrahyoid muscles. Fig. 8.169 Origin of common carotid arteries. TracheaEsophagusLeft common carotid arteryLeft internal jugular veinLeft subclavian arteryLeft subclavian veinClavicleSuperior vena cavaRight subclavian veinRight subclavian arteryRight internal jugular veinRight common carotid arteryArch of aortaLeft brachiocephalic veinRight brachiocephalic vein


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Anatomy_Gray. Fig. 8.170 Carotid triangle. SternocleidomastoidmuscleCarotid triangleSuperior belly ofomohyoid muscleCommon carotid arteryPosterior belly of digastric muscleInternal carotid arteryExternal carotid artery Fig. 8.171 Carotid system. Fig. 8.172 Glossopharyngeal nerve [IX] in the anterior triangle of the neck. Fig. 8.173 Vagus nerve [X] in the anterior triangle of the neck. Fig. 8.174 Accessory nerve [XI] in the posterior triangle of the neck. Fig. 8.175 Hypoglossal nerve [XII]. A. Surgical view of hypoglossal nerve in anterior triangle of the neck. B. Diagram. Hyoglossus muscleExternal carotidarterySuperior root ofansa cervicalisSuperior thyroid arteryInternal jugular veinInternal jugularveinPosterior belly ofdigastric muscle (cut )Stylohyoid muscleSternocleidomastoidbranch of occipital arteryHypoglossal nerveHypoglossal nerveSternocleidomastoid branchof occipital arteryPosterior belly of digastric muscleOccipital arteryAB


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Anatomy_Gray. Fig. 8.176 Transverse cervical nerve in the anterior triangle of the neck. Fig. 8.177 Ansa cervicalis. Hypoglossal nerveC1C3C2Superior root of ansa cervicalisInferior root of ansa cervicalisOmohyoid muscle(superior belly)Sternohyoid muscleSternothyroid muscleThyrohyoid muscleOmohyoid muscle(inferior belly) Fig. 8.178 Thyroid gland in the anterior triangle of neck. A. Anterior view. B. Transverse view. C. Ultrasound scan—compound axial view of the neck. D. Ultrasound scan—axial view of the neck. E. Nuclear medicine scan—normal thyroid uptake of pertechnetate in the neck. Fig. 8.179 Vasculature of the thyroid: anterior view. Fig. 8.180 Superior and inferior thyroid arteries and left and right recurrent laryngeal nerves and thyroid and parathyroid glands. A. Posterior view. B. Surgical (anterolateral) view of parathyroid gland with left lobe of thyroid retracted. BLeft lobe of thyroid glandParathyroid gland


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Anatomy_Gray. BLeft lobe of thyroid glandParathyroid gland Fig. 8.181 Surgical view of left lobe of enlarged thyroid (goiter) retracted to show close association with recurrent laryngeal nerve. Left lobe of thyroid glandLeft recurrent laryngeal nerve Fig. 8.182 Ectopic parathyroid adenoma in superior mediastinum. Noncontrast hybrid single photon emission computed tomography/computed tomography (SPECT/CT). A. Transverse view. B. Sagittal view. C. Coronal view. Fig. 8.183 Borders of the posterior triangle of the neck. Sternocleidomastoid muscleTrapezius muscleOmoclavicular orsubclavian triangleOccipital triangleHyoid bonePosteriortriangleSuperior belly ofomohyoid muscleInferior belly of omohyoid muscle Fig. 8.184 Muscles of the posterior triangle of the neck. Sternocleidomastoid muscleClavicleInferior belly of omohyoid muscleAcromion ofscapulaTrapezius muscleAnterior scalene muscleMiddle scalene musclePosterior scalene muscleLevator scapulae muscleSplenius capitis muscle


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Anatomy_Gray. Fig. 8.185 External jugular vein in the posterior triangle of the neck. Fig. 8.186 Arteries in the posterior triangle of the neck. Trapezius muscleMiddle scalene muscleTransverse cervical arteryBrachial plexusSuprascapular artery3rd part of subclavian arteryPhrenic nerveAnterior scalene muscleSubclavian veinExternal jugular veinInternal jugular veinClavicle1st part of subclavian arteryVagus nerveCommon carotid arteryThyrocervical trunkInferior thyroid arterySternocleidomastoid muscle Fig. 8.187 Accessory nerve and cutaneous branches of the cervical plexus in the posterior triangle of the neck. Fig. 8.188 Cervical plexus. Fig. 8.189 Prevertebral and lateral vertebral muscles supplied by cervical plexus. Fig. 8.190 Root of the neck. TracheaRib IManubrium of sternumCervical pleuraTI vertebraEsophagus Fig. 8.191 Vasculature of the root of the neck. Fig. 8.192 Nerves in the root of the neck. Fig. 8.193 Components of the sympathetic nervous system in the root of the neck.


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Anatomy_Gray. Fig. 8.191 Vasculature of the root of the neck. Fig. 8.192 Nerves in the root of the neck. Fig. 8.193 Components of the sympathetic nervous system in the root of the neck. Fig. 8.194 Cervical part of the sympathetic trunk. Fig. 8.195 Thoracic duct in the root of the neck. Fig. 8.196 Termination of lymphatic trunks in the root of the neck. Fig. 8.197 Lymphatic system in the neck. Fig. 8.198 Pharynx. Fig. 8.199 Neck regions (levels) that are used clinically to evaluate lymph nodes. Fig. 8.200 Line of attachment of the pharynx to the base of the skull.


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Anatomy_Gray. Fig. 8.198 Pharynx. Fig. 8.199 Neck regions (levels) that are used clinically to evaluate lymph nodes. Fig. 8.200 Line of attachment of the pharynx to the base of the skull. Cartilaginous position of pharyngotympanic tubeChoanae (posterior openings of nasal cavities)Pterygoid hamulusLine of attachment of pharynxRoughening on petrous part of temporal bone for attachment of levator veli palatiniExternal acoustic meatusPharyngeal tubercleJugular foramenCarotid canalMedial plate of pterygoid process of sphenoidPetrous part of temporal boneScaphoid fossa on sphenoid bone (for attachment of tensor veli palatini) Fig. 8.201 Attachments of the lateral pharyngeal wall. Fig. 8.202 Constrictor muscles of the pharynx. A. Lateral view. B. Posterior view.


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Anatomy_Gray. Fig. 8.201 Attachments of the lateral pharyngeal wall. Fig. 8.202 Constrictor muscles of the pharynx. A. Lateral view. B. Posterior view. ABPosition of palatopharyngeal sphincteron deep surface of superior constrictorSuperior constrictorMiddle constrictorInferior constrictorEsophagusPharyngeal tuberclePharyngeal fasciaStylohyoid ligamentStylopharyngeus musclePharyngeal rapheStyloid process Fig. 8.203 Longitudinal muscles of the pharynx. A. Stylopharyngeus muscle. B. Medial view. Fig. 8.204 Gaps between muscles in the pharyngeal wall. Pharyngeal fasciaStylopharyngeusSuperior constrictorMiddle constrictorInferior constrictorOropharyngealtriangle:structures (muscles,nerves, vessels)passing into and outof the oral cavityInternal laryngealnerve and vesselsEsophagusRecurrent laryngealnerve and vesselsTracheaMylohyoidBuccinator Fig. 8.205 Mucosal features of the pharynx. A. Lateral view. B. Posterior view with the pharyngeal wall opened. C. Superior view.


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Anatomy_Gray. Fig. 8.205 Mucosal features of the pharynx. A. Lateral view. B. Posterior view with the pharyngeal wall opened. C. Superior view. ABCFold overlyingpalatopharyngealsphincterTorus levatorius(fold overlyinglevator veli palatini)Torus tubariusPharyngeal recessPharyngeal tonsilPharyngeal opening of thepharyngotympanic tubeSalpingopharyngeal foldPalatine tonsilPalatopharyngeal arch(overliespalatopharyngeusmuscle)Laryngeal inletEsophagusTracheaValleculaLingual tonsilsPalatoglossal arch(margin of oropharyngeal isthmus)TongueNasal cavityNasopharynxOropharynxLaryngopharynxOropharyngealisthmusPharyngeal tonsilChoanaeTorus tubariusTorus levatoriusSoft palatePalatopharyngeal archPalatopharyngeal archPalatine tonsilValleculae (anterior to epiglottis)Laryngeal inletEsophagusPiriform fossaLingual tonsilLingual tonsilPalatine tonsilEpiglottisValleculaPiriform fossaSalpingopharyngealfoldPharyngealrecessesNasal cavityOral cavityTracheaLarynxPharynxEsophagus Fig. 8.206 Arterial supply of the pharynx.


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Anatomy_Gray. Fig. 8.206 Arterial supply of the pharynx. Pharyngeal branch(supplies roof of nasopharynx)Superficial temporal arteryAscending palatinearteryAscending pharyngeal arteryInternal carotid arteryCommon carotid arteryPharyngeal branchesInferior thyroid arteryThyrocervical trunkSubclavian arteryLingual arteryExternal carotid arteryFacial arteryTonsillar branchMaxillary artery Fig. 8.207 Venous and lymphatic drainage of the pharynx. Fig. 8.208 Innervation of the pharynx. A. Lateral view. B. Posterior view showing innervation of stylopharyngeus muscle. ABPharyngeal branch of [V2]Nasopharynx–sensory [V2]Oropharynx–sensory [IX]Laryngopharynx–sensory [X]Superiorlaryngeal nerveInferiorganglion of [X]External laryngeal nerve(branch of superior laryngealnerve from [X])Internal laryngeal nerve(branch of superiorlaryngeal nervefrom [X])Pharyngealbranch of [IX]Pharyngealbranch of [X][IX][V2]IXMotor branch to stylopharyngeus Fig. 8.209 Larynx. A. Relationship to other cavities. B. Lateral view.


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Anatomy_Gray. Fig. 8.209 Larynx. A. Relationship to other cavities. B. Lateral view. Fig. 8.210 Cricoid cartilage. A. Anterolateral view. B. Posterior view. Facet for articulation witharytenoid cartilageFacet for articulation withinferior horn of thyroid cartilageTracheaCricoidcartilageLaminaArchAirwayAFacet for articulation witharytenoid cartilageRidgeFacet for articulation with inferior horn of thyroid cartilageDepressionsB Fig. 8.211 Thyroid cartilage. A. Anterolateral view. B. Superior view. Fig. 8.212 Epiglottis. A. Anterolateral view. B. Posterior surface. CricoidTracheaEpiglottic tubercleThyro-epiglottic ligamentRight thyroid laminaAnterior surface of epiglottisPosterior surface of epiglottisAB Fig. 8.213 Arytenoid cartilages.


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Anatomy_Gray. CricoidTracheaEpiglottic tubercleThyro-epiglottic ligamentRight thyroid laminaAnterior surface of epiglottisPosterior surface of epiglottisAB Fig. 8.213 Arytenoid cartilages. ApexPosterior surfaceMedial surfaceRidge on anterolateral surfaceMuscular processArytenoidcartilageDepression for attachment of vocalis musclesDepression for attachment of vestibular ligamentBase (concave – for articulation with cricoid)Vocal processArticular facet forcorniculate cartilageAnterolateral surface Fig. 8.214 Corniculate and cuneiform cartilages. Fig. 8.215 Extrinsic ligaments of the larynx. Lateral thyrohyoid ligamentsAperture for internal branch of superior laryngeal nerve and associated arteryThyrohyoid membraneCricotracheal ligamentMedian thyrohyoid ligamentHyo-epiglottic ligamentHyoid boneTriticeal cartilage Fig. 8.216 Cricothyroid ligament. Fig. 8.217 Quadrangular membrane. Fig. 8.218 Fibro-elastic membrane of the larynx (superior view).


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Anatomy_Gray. Fig. 8.216 Cricothyroid ligament. Fig. 8.217 Quadrangular membrane. Fig. 8.218 Fibro-elastic membrane of the larynx (superior view). EpiglottisVestibular ligamentQuadrangular membraneConus elasticusMuscular process of arytenoidVocal process of arytenoidCorniculate cartilageVocal ligament Fig. 8.219 Movements of the cricothyroid joints. Fig. 8.220 Movements of the crico-arytenoid joints. Fig. 8.221 Laryngeal cavity. A. Posterolateral view. B. Posterior view (cut away). C. Superior view through the laryngeal inlet. D. Labeled photograph of the larynx, superior view.


Anatomy_Gray

Anatomy_Gray. Fig. 8.221 Laryngeal cavity. A. Posterolateral view. B. Posterior view (cut away). C. Superior view through the laryngeal inlet. D. Labeled photograph of the larynx, superior view. EpiglottisEpiglottisEpiglottisAry-epiglottic foldAry-epiglottic foldCut edge of mucosaLaryngeal sacculeVestibuleVestibuleCut edge of right thyroid laminaLaryngeal ventricleInfraglottic spaceInterarytenoid notchCorniculate tubercleCorniculate tubercleCuneiform tubercleCuneiform tubercleCuneiform tubercleLaryngeal inletLaryngeal inletVestibular fold(mucosa overlying vestibular ligament)Vestibular fold (false vocal cord)Vocal fold (mucosa overlying vocal ligament)Vocal fold (true vocal cord)TracheaCricoid archMiddle part of cavityLaryngeal sacculeRima vestibuliRima glottidisRima glottidis (opening between vocal cords)Interarytenoid foldCorniculate tubercleVestibular foldAry-epiglottic foldVocal fold ABCDLaryngopharynx (closed)Piriform recessTongueAnteriorPosterior Fig. 8.222 Cricothyroid muscle.


Anatomy_Gray

Anatomy_Gray. Fig. 8.222 Cricothyroid muscle. Fig. 8.223 Crico-arytenoid, oblique and transverse arytenoid, and vocalis muscles. Fig. 8.224 Thyro-arytenoid muscle. Superior thyroid notchAry-epiglottic part ofoblique arytenoid muscleSacculeThyro-arytenoid muscleThyro-epiglotticpart of thyro-arytenoid muscle Fig. 8.225 Laryngeal function. A. Quiet respiration. B. Forced inspiration. C. Phonation. D. Effort closure. E. Swallowing. Quiet respirationForced inspirationPhonationEffort closureSwallowingVocal foldVocal foldsclosedVestibular foldVestibularfolds closedAry-epiglottic foldLaryngeal inletLaryngealinlet narrowedEpiglottis swingsdown to arytenoidsEpiglottis• Vocal folds abducted and rima glottidis wide open• Vestibule open• Vocal folds adducted and stridulating as air is forced between them• Vestibule open• Vocal folds and vestibular folds adducted• Rima glottidis and vestibule closedABCDE Fig. 8.226 Arterial supply of the larynx, left lateral view.


Anatomy_Gray

Anatomy_Gray. Fig. 8.226 Arterial supply of the larynx, left lateral view. Fig. 8.227 Venous drainage of the larynx, anterior view. Superior laryngeal veinMiddle thyroid veinSuperior thyroid veinThyrohyoid membraneMedian cricothyroid ligamentInferior thyroid veinThyroid glandManubrium of sternumRight subclavian veinInferior laryngeal veinRight internal jugular veinHyoid bone Fig. 8.228 Innervation of the larynx. Inferior vagal ganglionLeft vagus nerveThyrohyoid membranePosition of vocal foldsMedian cricothyroid ligamentLeft recurrent laryngeal nerveTracheaLeft subclavian arteryAortic archLeft pulmonary arteryRight pulmonary arteryLigamentum arteriosumPulmonary trunkEsophagusManubriumRight subclavian arteryRight recurrent laryngeal nerveCricothyroid muscleRight vagus nerveExternal laryngeal nerveSuperior laryngeal nerveInternal laryngeal nerve Fig. 8.229 Nasal cavities (anterolateral view). Relationship to other cavities.


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Anatomy_Gray. Fig. 8.229 Nasal cavities (anterolateral view). Relationship to other cavities. Fig. 8.230 Nasal cavities. A. Floor, roof, and lateral walls. B. Conchae on lateral walls. C. Coronal section. D. Air channels in right nasal cavity. Fig. 8.231 Paranasal sinuses and nasolacrimal duct. Fig. 8.232 Regions of the nasal cavities. Fig. 8.233 Ethmoid bone. A. Overall shape. B. Coronal section through skull.


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Anatomy_Gray. Fig. 8.231 Paranasal sinuses and nasolacrimal duct. Fig. 8.232 Regions of the nasal cavities. Fig. 8.233 Ethmoid bone. A. Overall shape. B. Coronal section through skull. ABAnteriorPosteriorCrista galliLeft ethmoidal labyrinthOrbital plateUncinate processMiddle conchaPerpendicular plateChannel for frontonasal ductopening into frontal sinusRight ethmoidal labyrinthCribriform plateSuperior conchaEthmoidal bullaMiddle conchaUncinate processInfundibulumCranial cavityCribriform platePerpendicular plateNasal cavitiesOrbitOrbitMiddle ethmoidal cellsSuperior conchaEthmoidal bullaMiddle conchaUncinate processInferior concha boneVomerOral cavityPalatine process of maxillary boneMaxillarysinusMaxillarysinusOrbital plate ofethmoidal labyrinthOrbital plate offrontal boneCrista galli Fig. 8.234 External nose.


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Anatomy_Gray. Fig. 8.234 External nose. Nasal boneFrontal process of maxillaLacrimal boneNasolacrimal grooveMinor alar cartilagesSeptal cartilageNarisMajor alarcartilageSuperior margin ofseptal cartilageLateral process ofseptal cartilage Fig. 8.235 Paranasal sinuses. A. Anterior view. B. Posteroanterior skull radiograph. C. Paramedian view of right nasal cavity. D. Lateral skull radiograph. ABEthmoidalcellsFrontal sinusesZygomatic process of frontal boneSuperior orbital fissureFrontalsinusesEthmoidal cellsMaxillarysinusesMaxillary sinusRoots of posteriorupper molarsOrbital plate ofethmoid boneNasal septumForamen rotundum Fig. 8.236 Medial wall of the nasal cavity—the nasal septum. Nasal spine of frontal bonePerpendicular plate of ethmoid bonePituitary fossaSphenoidal sinusVomerNasal crest ofmaxillary andpalatine bonesIncisor crestSeptalcartilageNasal bone Fig. 8.237 Floor of the nasal cavity (superior view).


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Anatomy_Gray. Fig. 8.237 Floor of the nasal cavity (superior view). Septal cartilageNarisAnterior nasal spineIncisive canalPalatine process of maxillaHorizontal plate of palatineSoft palateNasal crestsMaxillary sinus Fig. 8.238 Roof of the nasal cavity. Cribriform plateOpening of sphenoidal sinusAla of vomerVomerSphenoidal rostrum(articulates in themidline with the vomer)Nasal bonesNasal spine of frontal bone Fig. 8.239 Lateral wall of the nasal cavity. A. Bones. B. Covered with mucosa. C. Conchae broken away at attachment to lateral wall. AFrontal process of maxillaSuperior conchaMiddle conchaMedial pterygoid plate ofsphenoid boneUncinate process of ethmoidPerpendicular plateof palatine boneInferior conchaMinor alar cartilageMajor alar cartilageLateral process ofseptal cartilageLacrimal boneNasal bone


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Anatomy_Gray. BCOpening ofpharyngotympanic tubeNasopharynxSoft palateInferior conchaMiddle conchaSuperior conchaOpening of posterior ethmoidalcells into lateral wall of superior meatusOpening of sphenoidal sinusinto spheno-ethmoidal recessOpening of middle ethmoidalcells onto ethmoidal bullaSemilunar hiatusOpening of maxillary sinus infloor of semilunar hiatus Opening of nasolacrimal ductInfundibulum opening of frontonasalduct that drains the frontal sinusand anterior ethmoidal cells Fig. 8.240 Nares. A. Inferior view. B. Associated muscles. NaresAMajor alar cartilageMinor alar cartilagesInferior nasal spine of maxillaConnective tissueSeptal cartilageBOrbitAttachment to frontalprocess of maxillaNasalis muscleAttachment to maxillaDepressor septi nasiNarisLevator labii superioris alaeque nasi Fig. 8.241 Choanae (posterior view). A. Overview. B. Magnified view.


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Anatomy_Gray. Fig. 8.241 Choanae (posterior view). A. Overview. B. Magnified view. Ala of vomerSphenoidal rostrumSphenoidal process of palatine bonePalatine boneMaxillaPalatovaginal canalVomerBAVomerSphenoid boneMedial pterygoidplate of sphenoidHorizontal plate of palatine bonePyramidal process of palatine boneOral cavityChoanaeChoanaeVaginal process of medial pterygoid plate Fig. 8.242 Gateways to the nasal cavities. Fig. 8.243 Arterial supply of the nasal cavities. A. Lateral wall of the right nasal cavity. B. Septum (medial wall of right nasal cavity).


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Anatomy_Gray. Fig. 8.242 Gateways to the nasal cavities. Fig. 8.243 Arterial supply of the nasal cavities. A. Lateral wall of the right nasal cavity. B. Septum (medial wall of right nasal cavity). ABAnterior ethmoidal arteryPosterior ethmoidal arterySuperior conchaMiddle conchaInferior conchaGreater palatine arteryPosterior lateral nasalbranches of sphenopalatine arterySphenopalatine arteryAlar branch oflateral nasal arteryExternal nasalartery from anteriorethmoidal arterySeptal branch ofanterior ethmoidal arterySeptal branch ofposterior ethmoidal arteryArea of significantanastomoses (proneto “nosebleeds”)Posterior septal branch ofsphenopalatine arteryTerminal part ofgreater palatine arterySeptal branch from nasalartery from superior labial artery Fig. 8.244 Venous drainage of the nasal cavities. Nasal vein in foramen cecumDrainage to cavernoussinus in cranial cavityDrainage to pterygoid plexusin infratemporal fossaDrainage to facial vein


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Anatomy_Gray. Fig. 8.244 Venous drainage of the nasal cavities. Nasal vein in foramen cecumDrainage to cavernoussinus in cranial cavityDrainage to pterygoid plexusin infratemporal fossaDrainage to facial vein Fig. 8.245 Innervation of the nasal cavities. A. Lateral wall of right nasal cavity. B. Medial wall of right nasal cavity. ABPosterior inferiorlateral nasal nervesInternal nasal branchesof infra-orbital nerveExternal nasalbranch of anteriorethmoidal nerveSeptal branch ofanterior ethmoidal nerveOlfactory nerve [I](septal branches)Olfactory bulbAnterior ethmoidal nerveOlfactory nerve [I]Sphenopalatine foramenPosterior superiorlateral nasal nervesNasal branch of anteriorsuperior alveolar nerveNasopalatine nerve Fig. 8.246 Lymphatic drainage of the nasal cavities. Fig. 8.247 Oral cavity. A. Relationship to other cavities. B. Oral vestibule and oral cavity proper.


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Anatomy_Gray. Fig. 8.246 Lymphatic drainage of the nasal cavities. Fig. 8.247 Oral cavity. A. Relationship to other cavities. B. Oral vestibule and oral cavity proper. Fig. 8.248 Base and lateral aspects of the skull. A. Features in the base of the skull related to structures associated with the oral cavity. B. Styloid process of the temporal bone.


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Anatomy_Gray. Fig. 8.248 Base and lateral aspects of the skull. A. Features in the base of the skull related to structures associated with the oral cavity. B. Styloid process of the temporal bone. Petrous part of temporal boneScaphoid fossaForamen ovaleSpine of sphenoidOpening to bony partof pharyngotympanic tubeForamen spinosumCarotid canalStyloid process of temporal boneMastoid processStylomastoid foramenJugular foramenRoughening for attachment of levator veli palatiniForamen lacerum (closed by cartilage)Cartilaginous part of pharyngotympanic tubeGreater wing of sphenoidMembranous lamina ofcartilaginous part of pharyngotympanic tubeAIncisive fossaPalatine process of maxillaAlveolar process of maxillaHorizontal plate of palatine boneGreater palatine foramenLesser palatine foramenLateral plate of pterygoid processMedial plate of pterygoid processIntermaxillary suturePosterior nasal spinePyramidal process of palatine bonePterygoid hamulus


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Anatomy_Gray. Fig. 8.249 Mandible. A. Superior view. B. Lateral view. C. Medial view. Fig. 8.250 Hyoid bone. A. Anterior view. B. Lateral view. Fig. 8.251 Buccinator muscle. Attachment to maxillaSuperior constrictorPterygomandibular rapheAttachment to mandibleBuccinatorOrbicularis orisModiolus Fig. 8.252 A. Mylohyoid muscles. B. Geniohyoid muscles. C. Lateral view. Superior mental spinesGeniohyoidGeniohyoidMylohyoidMylohyoidSuperior mental spinesMylohyoid lineInferior mental spinesRapheGreater hornBody of hyoidFree posterior marginSubmandibular fossaSublingual fossa ABC Fig. 8.253 Gateway into the floor of the oral cavity. Superiorconstrictorof pharynxMiddleconstrictorof pharynxMylohyoidTriangular aperture (oropharyngeal triangle) between mylohyoid,superior constrictor, and middle constrictor Fig. 8.254 Tongue. A. Paramedian sagittal section. B. Superior view.


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Anatomy_Gray. Fig. 8.254 Tongue. A. Paramedian sagittal section. B. Superior view. AOral part (anterior two-thirds)Foramen cecumand terminal sulcusPharyngeal part (posterior one-third)Hyoid boneRoot of tongueMylohyoid muscleGeniohyoid muscleMandibleInferior surfaceLower lipOral vestibuleFiliform papillaeTerminal sulcusForamen cecumBOropharynxPharyngeal part of tongueVallate papillaeFoliate papillaeFungiform papillae Fig. 8.255 Muscles of the tongue. Fig. 8.256 Genioglossus muscles. A. Posterior view. B. Lateral (left) view. Fig. 8.257 Hyoglossus muscles. A. Posterior view. B. Lateral (left) view. Fig. 8.258 Styloglossus muscles. Fig. 8.259 Palatoglossus muscles. Hard palatePalatine aponeurosisof soft palatePalatoglossus muscle (underliesthe palatoglossusarch of mucosa)Uvula Fig. 8.260 Arteries, veins, and nerves of the tongue.


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Anatomy_Gray. Hard palatePalatine aponeurosisof soft palatePalatoglossus muscle (underliesthe palatoglossusarch of mucosa)Uvula Fig. 8.260 Arteries, veins, and nerves of the tongue. Lingual nerve(from [V3])Chorda tympani (from [VII])Hypoglossalnerve [XII]OccipitalarterySternocleidomastoid branch of occipital arteryLingual arteryCommon carotid arteryInternal jugular veinDorsal lingual veinDeep lingual veinHyoglossusGlossopharyngealnerve [IX] Fig. 8.261 Innervation of the tongue. Fig. 8.262 Lingual nerve in the floor of the oral cavity (medial view). Fig. 8.263 Hypoglossal nerve and C1 fibers. Hypoglossal nerveC1C1 fibersC3C2ThyrohyoidSuperior root ofansa cervicalisNerve to thyrohyoid(C1)GeniohyoidNerve to geniohyoid (C1) Fig. 8.264 Parotid gland. MasseterBuccinatorParotid duct(penetrates buccinator oppositecrown of 2nd upper molar tooth)SternocleidomastoidParotid glandExternal acoustic meatus


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Anatomy_Gray. Fig. 8.264 Parotid gland. MasseterBuccinatorParotid duct(penetrates buccinator oppositecrown of 2nd upper molar tooth)SternocleidomastoidParotid glandExternal acoustic meatus Fig. 8.265 Submandibular and sublingual glands. A. Medial view. B. Posterior view. C. Anterior view. D. Anterosuperior view. Superior constrictor musclePterygomandibular rapheSmall ducts of sublingual glandSubmandibular ductSublingual glandSublingual glandSubmandibular ductGenioglossus muscleHyoglossus muscleSuperficialDeepSuperficialDeepSubmandibularglandLingual nerveABSubmandibular ductSublingual fold overlyingsublingual glandSublingual caruncleOpening ofsubmandibular ductOpening of leftsubmandibular ductSublingual carunclesLingual veinFrenulum of tongueOpening of ducts from sublingual glandCDDeep lingual veinFimbriated foldFrenulum of tongue Fig. 8.266 Summary of parasympathetic (secretomotor) innervation of glands in the head.


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Anatomy_Gray. Fig. 8.266 Summary of parasympathetic (secretomotor) innervation of glands in the head. Lacrimal glandGlands onpalatePterygopalatine ganglionPalatine nerveLabial glandsLingual glandsSublingual glandSubmandibular glandSubmandibular ganglionOtic ganglionAuriculotemporal nerve (from [V3])Parotid gland innervated by [IX]Chorda tympani[V][VII][IX]Preganglionic parasympathetic fibers from [IX]Greater petrosal nerveAll glands abovelevel of oral fissureinnervated by greater petrosal of [VII]All glands below level of oral fissureinnervated bychorda tympani of [VII] Fig. 8.267 Course of parasympathetic fibers carried in the chorda tympani nerve. Fig. 8.268 Summary of sympathetic innervation of glands in the head. Fig. 8.269 Palate. Fig. 8.270 A. Tensor veli palatini muscles and the palatine aponeurosis. B. Levator veli palatini muscles. C. Palatopharyngeus muscles.


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Anatomy_Gray. Fig. 8.269 Palate. Fig. 8.270 A. Tensor veli palatini muscles and the palatine aponeurosis. B. Levator veli palatini muscles. C. Palatopharyngeus muscles. Muscular part of tensor veli palatiniCartilaginous part ofpharyngotympanic tubeFibrous part of pharyngotympanic tubePalatine aponeurosisPterygoid hamulusPosition of palatopharyngealsphincterPharyngeal rapheSuperior constrictor of pharynxPterygomandibular rapheBuccinator musclePterygopalatine fossaABCNasal cavityMedial pterygoid plateLateral pterygoid plateNasal septumLevator veli palatiniPalatopharyngeus Fig. 8.271 Open mouth with soft palate. A. Oropharyngeal isthmus opened. B. Oropharyngeal isthmus closed.


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Anatomy_Gray. Fig. 8.271 Open mouth with soft palate. A. Oropharyngeal isthmus opened. B. Oropharyngeal isthmus closed. ABPalatoglossal archPalatopharyngeal archPosterior wall of oropharynxSoft palateSoft palateTongueUvulaPalatine tonsilAnterior margin oforopharyngeal isthmus(palatoglossal arch)Closure of oropharyngeal isthmus• Medial and downward movement of palatoglossal arches• Medial and downward movement of palatopharyngeal arches• Upward movement of tongue• Downward and forward movement of soft palate Fig. 8.272 Palatoglossus muscles and musculus uvulae. Musculus uvulaePalatoglossusfrom underside of aponeurosisPalatine tonsil Fig. 8.273 Arteries of the palate. Fig. 8.274 Palatine nerves and arteries. Incisive fossaNasopalatine nerveGreater palatine nerveGreater palatine foramenLesser palatine foramenLesser palatine nerveUvulaBranches from ascending palatine artery of facial artery and palatine branch of ascending pharyngeal arteryLesser palatine arteryGreater palatine artery


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Anatomy_Gray. Fig. 8.275 Venous and lymphatic drainage of the palate. Fig. 8.276 Innervation of the palate. Greater petrosal nerve (preganglionic parasympatheticand special sensory [taste])[VII]Deep petrosal nerve (postganglionic sympathetic)Superior cervical sympathetic ganglionSympathetic trunkPreganglionicsympathetic from T1UvulaInternal carotid arteryNerve of pterygoid canalLesser palatine nerveLesser palatine foramenGreater palatine nerveNasopalatine nerveGreater palatine foramenPalatine canalPterygopalatine ganglionNasopalatine nerveMaxillary nerve[V] Fig. 8.277 Oral fissure and lips. A. Anterior view. B. Sagittal section. PhiltrumVestibuleOrbicularis oris muscleOral fissureVermilion border of lipFacial arterySuperior and inferior labial arteriesABLabial salivary glandsArtery and veinVermilion bordersOrbicularis oris muscleBuccinator muscle Fig. 8.278 Teeth. A. Adult upper and lower permanent teeth. B. Deciduous (“baby”) teeth.


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Anatomy_Gray. Fig. 8.278 Teeth. A. Adult upper and lower permanent teeth. B. Deciduous (“baby”) teeth. AIncisorsCaninesPremolarsMolarsMolarsPremolarsCaninesIncisorsMaxillary sinusRoots related to maxillary sinusPremolars3212132121Roots related tomandibular canalMolarsCanineIncisorsUpperLowerMolarsIncisorsCaninesBUpperLower Fig. 8.279 Arteries and veins of the teeth. Cavernous sinusin cranial cavityEmissary veinsInfra-orbitalartery and veinPosterior superior alveolarartery and veinAnterior superior alveolarartery and veinInferior alveolar artery andvein in mandibular canalFacial veinInternal jugular veinExternal jugular veinExternal carotid arteryPterygoid plexus of veinsRetromandibular veinMaxillary veinMaxillary artery Fig. 8.280 Lymphatic drainage of the teeth and gums. Fig. 8.281 Innervation of the teeth. Fig. 8.282 Innervation of the teeth and gums.


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Anatomy_Gray. Fig. 8.280 Lymphatic drainage of the teeth and gums. Fig. 8.281 Innervation of the teeth. Fig. 8.282 Innervation of the teeth and gums. TeethAnterior superior alveolar nerve (from [V2])Middle superior alveolar nerve (from [V2])Posterior superioralveolar nerve (from [V2])UpperLowerMain trunk of inferioralveolar nerve (from [V3])Incisive branch of inferioralveolar nerve (from [V3])Nasopalatine nerve (from [V2])Greater palatine nerve (from [V2])GingivaeAnterior superior alveolar nerve (from [V2])Middle superior alveolar nerve (from [V2])Posterior superior alveolar nerve (from [V2]) Lingual nerve (from [V3])Buccal nerve (from [V3])Mental nerve from inferior alveolar nerve (from [V3]) Fig. 8.283 Anatomical position of the head and major landmarks. Lateral head and neck of a man.


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Anatomy_Gray. Fig. 8.283 Anatomical position of the head and major landmarks. Lateral head and neck of a man. External occipitalprotuberanceCervical spinal nervesExternal acoustic meatusSternocleidomastoid muscleAngle of mandibleMastoid processVertexZygomatic boneFrankfort lineInferior margin of orbitPosition of head of mandiblePosition of zygomatic arch[V1][V2][V3] Fig. 8.284 Visualizing structures at the CIII/IV and CVI vertebral levels. Lateral head and neck of a man. Vertebral level CVI• Arch of cricoid cartilage• Superior end of esophagus• Superior end of tracheaVertebral level CIII/IV• Upper margin of thyroid cartilage• Bifurcation of common carotid arteryBifurcation of common carotidFrankfort lineEsophagusArch of cricoidPharynx Fig. 8.285 How to outline the anterior and posterior triangles of the neck. A. In a woman, anterolateral view. The left anterior triangle is indicated. B. In a man, anterior view of the posterior triangle.


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Anatomy_Gray. ABMidline of neckAnterior margin ofsternocleidomastoidAnterior margin oftrapeziusClaviclePosterior margin ofsternocleidomastoidPosterior triangleAnterior triangleInferior margin of mandibleStructures coursing betweenhead and thorax are associatedwith the anterior trianglesStructures coursing betweenthorax/neck and upper limb areassociated with the posterior triangles Fig. 8.286 How to locate the median cricothyroid ligament. A. In a man, lateral view of head and neck. B. In a woman, lateral view of head and neck. C. In a man, anterior neck with the chin elevated. D. In a woman, anterior neck with the chin elevated. ABThyroid notchLaryngeal prominencePosition of mediancricothyroid ligamentArch of cricoid cartilage Thyroid notchLaryngeal prominencePosition of median cricothyroid ligamentArch of cricoidcartilageIsthmus of thyroid glandCD Fig. 8.287 How to find the thyroid gland. A. In a woman, anterior view of neck. B. In a man, anterior view of neck.


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Anatomy_Gray. Fig. 8.287 How to find the thyroid gland. A. In a woman, anterior view of neck. B. In a man, anterior view of neck. Position of oblique line on thyroid cartilageHyoid boneThyroid notchLaryngeal prominenceMedian cricothyroidligamentArch of cricoidLeft lobe of thyroid glandRight lobe of thyroid glandIsthmus of thyroid glandAB Fig. 8.288 Estimating the position of the middle meningeal artery. Lateral head and neck of a man. External earExternal acoustic meatusPterionFrankfort lineInferior margin of orbitSuperior margin of orbit Fig. 8.289 Major features of the face. Anterior head and neck of a woman. Region for testing [V1]Palpebral fissureOral fissureNostril[V1][V2][V3]Region fortesting [V2]Region for testingsensory of [V3]Orbicularis orisPhiltrumOrbicularis oculi


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Anatomy_Gray. Region for testing [V1]Palpebral fissureOral fissureNostril[V1][V2][V3]Region fortesting [V2]Region for testingsensory of [V3]Orbicularis orisPhiltrumOrbicularis oculi Fig. 8.290 Eye and lacrimal apparatus. A. Face of a woman. Lacrimal apparatus and the flow of tears are indicated. B. Left eye and surrounding structures. C. Left eye and surrounding structures with lower eyelid pulled down to reveal the lacrimal papilla and lacrimal punctum. ALacrimal glandFlow of tearsNasolacrimal ductInferior canaliculusLacrimal sacUpper eyelidLower eyelidLacrimal lakeScleraPupilPalpebral fissureLacrimal foldLacrimal caruncleIrisMedial commissureLateral commissureLacrimal papillaLacrimal punctumBC Fig. 8.291 External ear. Lateral view of the right ear of a woman. Fig. 8.292 Where to take arterial pulses in the head and neck. Fig. 8.293 Coronal CT scan demonstrating an orbital blowout fracture. eFig. 8.294 Ultrasound scan (axial view) demonstrating a stone in a dilated parotid duct.


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Anatomy_Gray. Fig. 8.293 Coronal CT scan demonstrating an orbital blowout fracture. eFig. 8.294 Ultrasound scan (axial view) demonstrating a stone in a dilated parotid duct. eFig. 8.295 Coronal MRI showing pituitary macroadenoma. Table 8.1 External foramina of the skull Table 8.2 Internal foramina of the skull Table 8.3 Dural venous sinuses Table 8.4 Cranial nerve functional components Other terminology used when describing functional components: *Special sensory, or special visceral afferent (SVA): smell, taste. Special somatic afferent (SSA): vision, hearing, balance. **Special visceral efferent (SVE) or branchial motor. Table 8.5 Cranial nerves (see Table 8.4 for abbreviations) Table 8.6 Parasympathetic ganglia of the head Table 8.7 Muscles of the face Table 8.8 Extrinsic (extra-ocular) muscles Table 8.9 Intrinsic muscles of the eye Table 8.10 Muscles of the middle ear Table 8.11 Muscles of mastication Table 8.12 Anterior triangle of neck (suprahyoid and infrahyoid muscles)


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Anatomy_Gray. Table 8.9 Intrinsic muscles of the eye Table 8.10 Muscles of the middle ear Table 8.11 Muscles of mastication Table 8.12 Anterior triangle of neck (suprahyoid and infrahyoid muscles) Table 8.13 Branches of the external carotid artery Table 8.14 Subdivisions of the anterior triangle of the neck—a regional approach Table 8.15 Muscles associated with the posterior triangle of the neck; parentheses indicate possible involvement Table 8.16 Prevertebral and lateral vertebral muscles Table 8.17 Constrictor muscles of the pharynx Table 8.18 Longitudinal muscles of the pharynx Table 8.19 Intrinsic muscles of the larynx Table 8.20 Muscles in the floor of the oral cavity Table 8.21 Muscles of the tongue Table 8.22 Muscles of the soft palate In the clinic


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Anatomy_Gray. Table 8.19 Intrinsic muscles of the larynx Table 8.20 Muscles in the floor of the oral cavity Table 8.21 Muscles of the tongue Table 8.22 Muscles of the soft palate In the clinic Some babies can be born with ossified fusion (synostosis) of one or more of the cranial sutures. This can result in an irregular head shape because the pattern and direction of skull growth are altered. In the majority of cases the cause is unknown, and in a minority of cases it may be caused by a genetic syndrome. In the clinic Medical imaging of the head


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Anatomy_Gray. In the clinic Medical imaging of the head Until recently, the standard method of imaging the head was plain radiography. The radiographs are taken in three standard projections—the posteroanterior view, the lateral view, and the Towne’s view (anteroposterior [AP] axial—head in anatomical position). Additional views are obtained to assess the foramina at the base of the skull and the facial bones. Currently, skull radiographs are used in cases of trauma, but such use is declining. Skull fractures are relatively easily detected (Fig. 8.29). The patient is assessed and treatment is based upon the underlying neurological or potential neurological complications.


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Anatomy_Gray. Since the development of computed tomography (CT), cerebral CT has become the “workhorse” of neuroradiological examination. It is ideally used for head injury because the brain and its coverings can be easily and quickly examined and blood is easily detected. By altering the mathematical algorithm of the data set the bones can also be demonstrated. With intravenous contrast, CT angiography can be used to demonstrate the position and the size of an intracerebral aneurysm before endovascular treatment. Magnetic resonance imaging (MRI) is unsurpassed by other imaging techniques in its ability for contrast resolution. The brain and its coverings, cerebrospinal fluid (CSF), and vertebral column can be easily and quickly examined. Newer imaging sequences permit CSF suppression to define periventricular lesions.


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Anatomy_Gray. Magnetic resonance angiography has been extremely useful in determining the completeness of the intracranial vasculature (circle of Willis), which is necessary in some surgical conditions. MRI is also a powerful tool in the assessment of carotid stenosis. It is now possible to carry out intracranial Doppler studies, which enable a surgeon to detect whether a patient is experiencing cerebral embolization from a carotid plaque. Extracranial ultrasound is extremely important in tumor staging and in assessing neck masses and the carotid bifurcation (Fig. 8.30). Ultrasound is useful in children because they have an acoustic window through the fontanelles. In the clinic Fractures of the skull vault


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Anatomy_Gray. Ultrasound is useful in children because they have an acoustic window through the fontanelles. In the clinic Fractures of the skull vault The skull vault is a remarkably strong structure because it protects our most vital organ, the brain. The shape of the skull vault is of critical importance and its biomechanics prevent fracture. From a clinical standpoint skull fractures alert clinicians to the nature and force of an injury and potential complications. The fracture itself is usually of little consequence (unlike, say, a fracture of the tibia). Of key importance is the need to minimize the extent of primary brain injury and to treat potential secondary complications, rather than focusing on the skull fracture. Skull fractures that have particular significance include depressed skull fractures, compound fractures, and pterion fractures.


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Anatomy_Gray. In a depressed skull fracture a bony fragment is depressed below the normal skull convexity. This may lead to secondary arterial and venous damage with hematoma formation. A primary brain injury can also result from this type of fracture. In a compound fracture there is a fracture of the bone together with a breach of the skin, which may allow an infection to enter. Typically these fractures are associated with scalp lacerations and can usually be treated with antibiotics. Important complications of compound fractures include meningitis, which may be fatal. A more subtle type of compound fracture involves fractures across the sinuses. These may not be appreciated on first inspection, but are an important potential cause of morbidity and should be considered in patients who develop intracranial infections secondary to trauma.


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Anatomy_Gray. The pterion is an important clinical point on the lateral aspect of the skull. At the pterion the frontal, parietal, greater wing of the sphenoid, and temporal bones come together. Importantly, deep to this structure is the middle meningeal artery. An injury to this point of the skull is extremely serious because damage to this vessel may produce a significant extradural hematoma, which can be fatal. In the clinic Hydrocephalus is a dilation of the cerebral ventricular system, which is due to either an obstruction to the flow of CSF, an overproduction of CSF, or a failure of reabsorption of CSF.


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Anatomy_Gray. Hydrocephalus is a dilation of the cerebral ventricular system, which is due to either an obstruction to the flow of CSF, an overproduction of CSF, or a failure of reabsorption of CSF. Cerebrospinal fluid is secreted by the choroid plexus within the lateral, third, and fourth ventricles of the brain. As it is produced it passes from the lateral ventricles through the interventricular foramina (the foramina of Monro) to enter the third ventricle. From the third ventricle it passes through the cerebral aqueduct (aqueduct of Sylvius) into the fourth ventricle, and from here it passes into the subarachnoid space via the midline foramen or the two lateral foramina (foramen of Magendie and foramina of Luschka). The CSF passes around the spinal cord inferiorly, envelops the brain superiorly, and is absorbed through the arachnoid granulations in the walls of the dural venous sinuses. In adults almost half a liter of CSF is produced per day.


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Anatomy_Gray. In adults the commonest cause of hydrocephalus is an interruption of the normal CSF absorption through the arachnoid granulations. This occurs when blood enters the subarachnoid space after subarachnoid hemorrhage, passes over the brain, and interferes with normal CSF absorption. To prevent severe hydrocephalus it may be necessary to place a small catheter through the brain into the ventricular system to relieve the pressure. Other causes of hydrocephalus include congenital obstruction of the aqueduct of Sylvius and a variety of tumors (e.g., a midbrain tumor), where the mass obstructs the aqueduct. Rare causes include choroid plexus tumors that secrete CSF.


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Anatomy_Gray. In children, hydrocephalus is always dramatic in its later stages. The hydrocephalus increases the size and dimensions of the ventricle, and as a result the brain enlarges. Because the skull sutures are not fused, the head expands. Cranial enlargement in utero may make a vaginal delivery impossible, and delivery then has to be by caesarean section. Both CT and MRI enable a radiologist to determine the site of obstruction and in most cases the cause of the obstruction. A distinction must be made between ventricular enlargement due to hydrocephalus and that due to a variety of other causes (e.g., cerebral atrophy). In the clinic Leakage of CSF from the subarachnoid space may occur after any procedure in and around the brain, spinal cord, and meningeal membranes. These procedures include lumbar spine surgery, epidural injection, and CSF aspiration.


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Anatomy_Gray. In “cerebrospinal fluid leak” syndrome, CSF leaks out of the subarachnoid space and through the dura mater for no apparent reason. The clinical consequences of this include dizziness, nausea, fatigue, and a metallic taste in the mouth. Other effects also include facial nerve weakness and double vision. In the clinic Meningitis is a rare infection of the leptomeninges (the leptomeninges are a combination of the arachnoid mater and the pia mater). Infection of the meninges typically occurs via a blood-borne route, though in some cases it may be by direct spread (e.g., trauma) or from the nasal cavities through the cribriform plate in the ethmoid bone. Certain types of bacterial inflammation of the meninges are so virulent that overwhelming inflammation and sepsis with cerebral irritation can cause the patient to rapidly pass into a coma and die. Meningitis is usually treatable with antibiotics.


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Anatomy_Gray. Meningitis is usually treatable with antibiotics. Certain types of bacteria that produce meningitis produce other effects; for example, subcutaneous hemorrhage (ecchymoses) is a feature of meningococcal meningitis. The typical history of meningitis is nonspecific at first. The patient may have mild headache, fever, drowsiness, and nausea. As the infection progresses, photophobia (light intolerance) and ecchymosis may ensue. Straight leg raising causes marked neck pain and discomfort (Kernig’s sign) and an emergency hospital admission is warranted. Immediate treatment consists of very-high-dose intravenous antibiotics and supportive management. In the clinic Determination of the anatomical structure from which a tumor arises is of the utmost importance, particularly when it arises within the cranial vault. Misinterpretation of the location of a lesion and its site of origin may have devastating consequences for the patient.


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Anatomy_Gray. When assessing any lesion in the brain, it is important to define whether it is intra-axial (within the brain) or extra-axial (outside the brain). Typical extra-axial tumors include meningiomas (tumors of the meninges) and acoustic neuromas. Meningiomas typically arise from the meninges, with preferred sites including regions at and around the falx cerebri, the free edge of the tentorium cerebelli, and the anterior margin of the middle cranial fossa. Acoustic neuromas are typically at and around the vestibulocochlear nerve [VIII] and in the cerebellopontine angle. Intra-axial lesions are either primary or secondary. By far the commonest type are the secondary brain lesions, which in most cases are metastatic tumor deposits. Metastatic tumor lesions are typically found in patients with either breast carcinoma or lung carcinoma, though many other malignancies can give rise to cerebral metastases.


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Anatomy_Gray. Metastatic tumor lesions are typically found in patients with either breast carcinoma or lung carcinoma, though many other malignancies can give rise to cerebral metastases. Primary brain lesions are rare and range from benign tumors to extremely aggressive lesions with a poor prognosis. These tumors arise from the different cell lines and include gliomas, oligodendrocytomas, and choroid plexus tumors. Primary brain tumors may occur at any age, though there is a small peak incidence in the first few years of life followed by a later peak in early to middle age. In the clinic


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Anatomy_Gray. In the clinic A stroke, or cerebrovascular accident (CVA), is defined as the interruption of blood flow to the brain or brainstem resulting in impaired neurological function lasting more than 24 hours. Neurological impairment resolving within 24 hours is known as a transient ischemic attack (TIA) or mini-stroke. Based on their etiology, strokes are broadly classified as either ischemic or hemorrhagic. Ischemic strokes are further divided into those caused by thrombotic or embolic phenomena. The latter is by far the commonest type of stroke and is often caused by emboli that originate from atherosclerotic plaques in the carotid arteries that migrate into and block smaller intracranial vessels. Hemorrhagic strokes are caused by rupture of blood vessels.


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Anatomy_Gray. The risk factors for stroke are those of cardiovascular disease, such as diabetes, hypertension, and smoking. In younger patients underlying clotting disorders, use of oral contraceptives, and illicit substance abuse (such as cocaine) are additional causes. The symptoms and signs of a stroke depend on the distribution of impaired brain perfusion. Common presentations include rapid-onset hemiparesis or hemisensory loss, visual field deficits, dysarthria, ataxia, and a decreased level of consciousness. Stroke is a neurological emergency. It is therefore important to establish the diagnosis as early as possible so that urgent and potentially life-saving treatment can be administered. Potent thrombolytic (blood-thinning) drugs can restore cerebral blood flow and improved patient outcome if administered within 3 to 4.5 hours of onset of the patient’s symptoms.


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Anatomy_Gray. Following initial clinical history taking and neurological examination, all patients with suspected stroke should undergo urgent brain imaging with computed tomography (CT). This is to identify hemorrhagic strokes for which thrombolytic therapy is contraindicated and to exclude an alternative diagnosis such as malignancy. In ischemic stroke, early CT imaging may appear normal or can show a relatively darker area of low density that corresponds to the region of abnormal brain perfusion. Due to subsequent brain edema and swelling, the affected brain also loses its normal sulcal pattern (Fig. 8.40A). If thrombolysis is performed, a 24-hour follow-up CT scan is routinely carried out to evaluate for complications such as intracranial hemorrhage.


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Anatomy_Gray. Additional diagnostic workup of stroke includes hematological and biochemical blood tests to identify causes such as hypoglycemia or underlying clotting disorders. A toxicology screen may be useful to identify substance intoxication, which can mimic stroke.


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Anatomy_Gray. The full extent of neurological injury can be evaluated on subsequent magnetic resonance imaging (MRI) of the brain, which has better soft tissue resolution compared to CT. MRI is also useful for identifying strokes that may be too small to detect on a CT scan. MRI scans are produced by using complicated algorithms that create a series of images, also known as sequences. Various sequences can be obtained to assess different anatomical and physiological properties of the brain. A stroke, whether acute or chronic, will appear as a bright region on a sequence that is sensitive to fluid (T2 weighted) (Fig. 8.40B). To identify whether a stroke is acute, further sequences are obtained, known as diffusion-weighted imaging (DWI) (Fig. 8.40C) and the apparent diffusion coefficient (ADC) (Fig. 8.40D) map. These evaluate the diffusion of water molecules in the brain. If the region of abnormality appears bright on the DWI sequence and dark on the ADC map, this is known as restricted diffusion,


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Anatomy_Gray. map. These evaluate the diffusion of water molecules in the brain. If the region of abnormality appears bright on the DWI sequence and dark on the ADC map, this is known as restricted diffusion, which is compatible with an acute stroke. These changes can persist for up to a week after the initial insult.


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Anatomy_Gray. Imaging of the carotid and vertebral arteries is also performed to assess for any treatable atherosclerotic changes and stenosis. This can be done with ultrasound, CT, or less frequently, MRI. Management of a stroke is multidisciplinary. Supportive treatment to stabilize the patient is a priority. Stroke specialists, speech and language therapists, occupational therapists, and physiotherapists have key roles in patient rehabilitation. Long-term use of antiplatelet drugs such as aspirin and modification of cardiovascular disease risk factors are important in the secondary prevention of stroke. In the clinic Endarterectomy is a surgical procedure to remove atheromatous plaque from arteries.


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Anatomy_Gray. In the clinic Endarterectomy is a surgical procedure to remove atheromatous plaque from arteries. Atheromatous plaques occur in the subendothelial layer of vessels and consist of lipid-laden macrophages and cholesterol debris. The developing plaque eventually accumulates fibrous connective tissue and calcifies. Plaque commonly occurs around vessel bifurcations, limiting blood flow, and may embolize to distal organs. During endarterectomy, plaque is removed and the vessel reopened. In many instances a patch of material is sewn over the hole in the vessel, enabling improved flow and preventing narrowing from the suturing of the vessel. In the clinic


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Anatomy_Gray. In the clinic Cerebral aneurysms arise from the vessels in and around the cerebral arterial circle (of Willis). They typically occur in and around the anterior communicating artery, the posterior communicating artery, the branches of the middle cerebral artery, the distal end of the basilar artery (Fig. 8.41), and the posterior inferior cerebellar artery.


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Anatomy_Gray. As the aneurysms enlarge, they have a significant risk of rupture. Typically patients have no idea that there is anything wrong. As the aneurysm ruptures, the patient complains of a sudden-onset “thunderclap” headache that produces neck stiffness and may induce vomiting. In a number of patients death ensues, but many patients reach the hospital, where the diagnosis is established. An initial CT scan demonstrates blood within the subarachnoid space, and this may be associated with an intracerebral bleed. Further management usually includes cerebral angiography, which enables the radiologist to determine the site, size, and origin of the aneurysm.


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Anatomy_Gray. Usually patients undergo complex surgery to ligate the neck of the aneurysm. More recently radiological intervention has superseded the management of some aneurysms in specific sites. This treatment involves cannulation of the femoral artery, and placement of a long catheter through the aorta into the carotid circulation and thence into the cerebral circulation. The tip of the catheter is placed within the aneurysm and is packed with fine microcoils (Fig. 8.42), which seals the rupture. In the clinic Summary of relationships and clinical significance of the scalp and meninges (Fig. 8.47). In the clinic Head trauma is a common injury and is a significant cause of morbidity and death. Head injury may occur in isolation, but often the patient has other injuries; it should always be suspected in patients with multiple injuries. Among patients with multiple trauma, 50% die from the head injury. At the time of the initial head injury two processes take place.


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Anatomy_Gray. At the time of the initial head injury two processes take place. First the primary brain injury may involve primary axonal and cellular damage, which results from the shearing deceleration forces within the brain. These injuries are generally not repairable. Further primary brain injuries include intracerebral hemorrhage and penetrating injuries, which may directly destroy gray and white matter. The secondary injuries are sequelae of the initial trauma. They include scalp laceration, fracture of the cranial vault, disruption of intracerebral arteries and veins, intracerebral edema, and infection. In most cases these can be treated if diagnosed early, and rapid and effective treatment will significantly improve the patient’s recovery and prognosis. In the clinic Types of intracranial hemorrhage The many causes of a primary brain hemorrhage include aneurysm rupture, hypertension (intracerebral hematoma secondary to high blood pressure), and bleeding after cerebral infarction.


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Anatomy_Gray. The many causes of a primary brain hemorrhage include aneurysm rupture, hypertension (intracerebral hematoma secondary to high blood pressure), and bleeding after cerebral infarction. An extradural hemorrhage (Fig. 8.48) is caused by arterial damage and results from tearing of the branches of the middle meningeal artery, which typically occurs in the region of the pterion. Blood collects between the periosteal layer of the dura and the calvaria and under arterial pressure slowly expands. The typical history is of a blow to the head (often during a sporting activity) that produces a minor loss of consciousness. Following the injury the patient usually regains consciousness and has a lucid interval for a period of hours. After this, rapid drowsiness and unconsciousness ensue, which may lead to death.


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Anatomy_Gray. A subdural hematoma (Fig. 8.49) results from venous bleeding, usually from torn cerebral veins where they enter the superior sagittal sinus. The tear and resulting seepage of blood separates the thin layer of dural border cells from the rest of the dura as the hematoma develops. Patients at most risk of developing a subdural hematoma are the young and elderly. The increased CSF space in patients with cerebral atrophy results in a greater than normal stress on the cerebral veins entering the sagittal sinus. The clinical history usually includes a trivial injury followed by an insidious loss of consciousness or alteration of personality. Subarachnoid hemorrhage (Fig. 8.50) may occur in patients who have undergone significant cerebral trauma, but typically it results from a ruptured intracerebral aneurysm arising from the vessels supplying and around the arterial circle (of Willis). In the clinic Tuberculosis of the central nervous system


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Anatomy_Gray. In the clinic Tuberculosis of the central nervous system Tuberculosis (TB) may invade the central nervous system, including the brain, spinal cord, and meninges (Fig. 8.51). Symptoms of brain TB include headache, neck stiffness, weight loss, and fever. Symptoms of spinal cord TB include leg weakness and fecal and urinary incontinence. Meningitis can cause altered mental status, fever, and seizures. Treatment usually requires a cocktail of drugs for 1 year, but treatment for brain TB can require 2 years. In the clinic Emissary veins connect extracranial veins with intracranial veins and are important clinically because they can be a conduit through which infections can enter the cranial cavity. Emissary veins lack valves, as do the majority of veins in the head and neck. In the clinic


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Anatomy_Gray. In the clinic Concussion (mild traumatic brain injury [MTBI]) is the most common type of traumatic brain injury. The injury typically results from a rapid deceleration of the head or by a rotation of the brain within the cranial cavity. General symptoms of MTBI can include posttraumatic amnesia, confusion, loss of consciousness, headache, dizziness, vomiting, lack of motor coordination, and light sensitivity. The diagnosis of concussion, MTBI, is based on the event, the current neurological status, and the state of consciousness of the patient. In the clinic Clinical assessment of patients with head injury Clinical assessment of patients with head injury always appears relatively straightforward. In reality it is usually far from straightforward. Patients may have a wide spectrum of modes of injury from a simple fall to complex multiple trauma. The age of the patient and ability to communicate about the injuries are important factors.


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Anatomy_Gray. Patients may have a wide spectrum of modes of injury from a simple fall to complex multiple trauma. The age of the patient and ability to communicate about the injuries are important factors. The circumstances in which the injury may have occurred should be documented because some head injuries result from a serious assault, and the physician may be required to give evidence to a court of law. Determining the severity of head injury may be difficult because some injuries occur as a result of or in association with alcohol intoxication. Even when the diagnosis has been made and the correct management has been instigated, the circumstances in which the injury occurred and the environment to which the patient will return after treatment need to be reviewed to prevent further injuries (e.g., an elderly person tripping on loose carpet on a staircase).


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Anatomy_Gray. A thorough clinical examination includes all systems, but with a special focus on the central and peripheral nervous systems. The level of consciousness must also be assessed and accurately documented using the Glasgow Coma Scale, which allows clinicians to place a numerical value upon the level of consciousness so that any deterioration or improvement can be measured and quantified. The Glasgow Coma Scale was proposed in 1974 and is now widely accepted throughout the world. There is a total score of 15 points, such that 15/15 indicates that the patient is alert and fully oriented, whereas 3/15 indicates a severe and deep coma. The points score comprises a best motor response (total of 6 points), best verbal response (total of 5 points), and best eye movement response (total of 4 points). In the clinic Treatment of head injury


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Anatomy_Gray. In the clinic Treatment of head injury Treatment of primary brain injury is extremely limited. Axonal disruption and cellular death are generally irrecoverable. Whenever the brain is injured, like most tissues, it swells. Because the brain is encased within a fixed space (the skull), swelling impairs cerebral function and has two other important effects. First, the swelling compresses the blood supply into the skull, resulting in a physiologically dramatic increase in blood pressure. Second, the cerebral swelling may be diffuse, eventually squeezing the brain and brainstem through the foramen magnum (coning). This compression and disruption of the brainstem may lead to a loss of basic cardiorespiratory function, and death will ensue. Focal cerebral edema may cause one side of the brain to herniate beneath the falx cerebri (falcine herniation).


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Anatomy_Gray. Simple measures to prevent the swelling include hyperventilation (which alters the intracerebral acid–base balance and decreases swelling) and intravenous corticosteroids (though their action is often delayed). Extracerebral hematoma may be removed surgically. The outcome of patients with head injury depends on how the secondary injury is managed. Even with a severe primary injury, patients may recover to lead a normal life. In the clinic


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Anatomy_Gray. The outcome of patients with head injury depends on how the secondary injury is managed. Even with a severe primary injury, patients may recover to lead a normal life. In the clinic The skull is a closed bony compartment, and the brain and cerebrospinal fluid are maintained physiologically within a narrow intracranial pressure range. Any new space-occupying lesion, such as a hematoma, an injury that leads to brain swelling, or a brain tumor, can increase intracranial pressure and compress the brain. In severe cases, the brain may be squeezed down into the foramen magnum, giving it a cone shape, termed cerebral herniation, or “coning.” This may in turn compress the brainstem and upper cervical spinal cord, which can be fatal.


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Anatomy_Gray. Congenital herniation or coning of the cerebellar tonsils through the foramen magnum can also occur if the posterior fossa is too small, a condition known as Chiari I malformation (Fig. 8.52). This often causes no problems in childhood and may only start causing symptoms in adulthood. In the clinic In the clinic Overview of cranial nerves Afferent—Trigeminal nerve (CN V) Efferent—Facial nerve (CN VII) Afferent—Glossopharyngeal nerve (CN IX) Efferent—Vagus nerve (CN X) Afferent—optic nerve (CN II) Efferent—oculomotor nerve (CN III) Fig. 8.55 Overview of cranial nerves.


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Anatomy_Gray. Glossopharyngeal nerve [IX]Special sensory – taste (posterior 1/3 of tongue)Somatic sensory – posterior 1/3 of tongue, oropharynx,palatine tonsil, middle ear, pharyngotympanic tube, andmastoid air cellsBranchial motor – stylopharyngeusVisceral motor – (parasympathetic) – secretomotor to theparotid glandVisceral sensory – from carotid body and sinusFacial nerve [VII] Branchial motor – all muscles of facial expression, andstapedius, stylohyoid, and posterior belly of digastricEfferent (motor) fibersV3V3V2V1Afferent (sensory) fibersFacial nerve [VII] (intermediate nerve)Special sensory – taste (anterior 2/3 of tongue)Somatic sensory – part of external acoustic meatus anddeeper parts of auricleVisceral motor (parasympathetic) – secretomotor to allsalivary glands except for parotid gland; all mucous glandsassociated with the oral and nasal cavities; lacrimal glandVestibulocochlear nerve [VIII]Special sensory – hearing and balanceOlfactory nerve [I]Special sensory – smellOptic nerve


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Anatomy_Gray. all mucous glandsassociated with the oral and nasal cavities; lacrimal glandVestibulocochlear nerve [VIII]Special sensory – hearing and balanceOlfactory nerve [I]Special sensory – smellOptic nerve [II]Special sensory – visionTrigeminal nerve [V] sensory rootSomatic sensory – eyes, orbital contents, face, sinuses, teeth, nasal cavities, oral cavity, anterior 2/3 of tongue, nasopharynx, dura, anterior part of external ear,and part of external acoustic meatusTrigeminal nerve [V] motor rootBranchial motor – the four muscles of mastication(medial pterygoid, lateral pterygoid, masseter, temporalis)and mylohyoid, anterior belly of digastric, tensor tympani,and tensor veli palatiniOculomotor nerve [III]Somatic motor – five extra-ocular muscles (superior rectus, medial rectus,inferior oblique, inferior rectus, and levator palpebrae superioris)Visceral motor – ciliary muscles and sphincter pupillae musclesTrochlear nerve [IV]Somatic motor – one extra-ocularmuscle (superior oblique)Abducent


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Anatomy_Gray. inferior rectus, and levator palpebrae superioris)Visceral motor – ciliary muscles and sphincter pupillae musclesTrochlear nerve [IV]Somatic motor – one extra-ocularmuscle (superior oblique)Abducent nerve [VI]Somatic motor – one extra-ocularmuscle (lateral rectus)Hypoglossal nerve [XII]Somatic motor – all muscles of thetongue except palatoglossusAccessory nerve [XI]Branchial motor – sternocleidomastoidand trapeziusVagus nerve [X]Somatic sensory – larynx, laryngopharynx, deeper parts ofauricle, and part of external acoustic meatusSpecial sensory – taste from epiglottis and pharynxBranchial motor – all muscles of pharynx except for stylopharyngeus; all muscles of the soft palate except for tensor veli palatini, all intrinsic muscles of larynxVisceral motor – (parasympathetic) – thoracic viscera andabdominal viscera to end of midgutVisceral sensory – thoracic viscera and abdominal viscerato end of midgut, chemoand baroreceptors(and in some cases carotid body)


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Anatomy_Gray. In the clinic Facelift surgery (rhytidectomy) aims to lift up and pull back the skin in the lower half of the face and neck to make the face more taught. Careful placement of the incisions is important to ensure there is no skin or facial distortion and to avoid hair loss. The commonest incisions are placed in the temporal region on each side, extending to the helices of the ears, then tracking behind the tragus, around the earlobes, and then to the occiput.


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Anatomy_Gray. Botox is derived from the toxin produced by the bacterium Clostridium botulinum, which blocks neuromuscular junctions resulting in muscle relaxation. It is used in many therapies including strabismus (crossed eyes) where it is injected into extra-ocular muscles. Its injection is also used to treat uncontrolled blinking (blepharospasm), spastic muscle conditions, and overactive bladder disorders, as well as to relax facial muscles to improve the cosmetic appearances of lines and wrinkles and to treat patients with excessive sweating (hyperhidrosis). In the clinic The parotid gland is the largest of the paired salivary glands and is enclosed within the split investing layer of deep cervical fascia. The parotid gland produces a watery saliva and salivary amylase, which are necessary for food bolus formation, oral digestion, and smooth passage of the bolus into the upper gastrointestinal tract. Tumors of the parotid gland


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Anatomy_Gray. Tumors of the parotid gland The commonest tumors of the parotid gland (Fig. 8.63) are benign and typically involve the more superficial part of the gland. These include pleomorphic adenoma and adenolymphoma. Their importance is in relation to their anatomical position. The relationship of any tumor to the branches of the facial nerve [VII] must be defined because resection of the tumor may damage the nerve. It is not uncommon for stones to develop within the parotid gland. They typically occur within the main confluence of the ducts and within the main parotid duct. The patient usually complains of intense pain when salivating and tends to avoid foods that produce this symptom. The pain can be easily reproduced in the clinic by squirting lemon juice into the patient’s mouth.


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Anatomy_Gray. Surgery depends upon where the stone is. If it is within the anterior aspect of the duct, a simple incision in the buccal mucosa with a sphincterotomy may allow removal. If the stone is farther back within the main duct, complete gland excision may be necessary. In the clinic The complexity of the facial nerve [VII] is demonstrated by the different pathological processes and sites at which these processes occur.


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Anatomy_Gray. In the clinic The complexity of the facial nerve [VII] is demonstrated by the different pathological processes and sites at which these processes occur. The facial nerve [VII] is formed from the nuclei within the brainstem emerging at the junction of the pons and the medulla. It enters the internal acoustic meatus, passes to the geniculate ganglion (which gives rise to further branches), and emerges from the skull base after a complex course within the temporal bone, leaving through the stylomastoid foramen. It enters the parotid gland and gives rise to five terminal groups of branches that supply muscles in the face and a number of additional branches that supply deeper or more posterior muscles. A series of lesions may affect the nerve along its course, and it is possible, with good clinical expertise, to determine the exact site of the lesion in relation to the course of the nerve.


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Anatomy_Gray. A primary brainstem lesion affecting the motor nucleus of the facial nerve [VII] would lead to ipsilateral (same side) weakness of the whole face. However, because the upper part of the nucleus receives motor input from the left and right cerebral hemispheres a lesion occurring above the nucleus leads to contralateral lower facial weakness. In this example, motor innervation to the upper face is spared because the upper part of the nucleus receives input from both hemispheres. Preservation and loss of the special functions are determined by the extent of the lesion. Lesions at and around the geniculate ganglion Typically lesions at and around the geniculate ganglion are accompanied by loss of motor function on the whole of the ipsilateral (same) side of the face. Taste to the anterior two-thirds of the tongue, lacrimation, and some salivation also are likely to be affected because the lesion is proximal to the greater petrosal and chorda tympani branches of the nerve.


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Anatomy_Gray. Lesions at and around the stylomastoid foramen Lesions at and around the stylomastoid foramen are the commonest abnormality of the facial nerve [VII] and usually result from a viral inflammation of the nerve within the bony canal before exiting through the stylomastoid foramen. Typically the patient has an ipsilateral loss of motor function of the whole side of the face. Not only does this produce an unusual appearance, but it also complicates chewing of food. Lacrimation and taste may not be affected if the lesion remains distal to the greater petrosal and chorda tympani branches that originate deep in the temporal bone. In the clinic Trigeminal neuralgia (tic douloureux) is a complex sensory disorder of the sensory root of the trigeminal nerve. Typically the pain is in the region of the mandibular [V3] and maxillary [V2] nerves, and is usually of sudden onset, is excruciating in nature, and may be triggered by touching a sensitive region of skin.


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Anatomy_Gray. The etiology of trigeminal neuralgia is unknown, although anomalous blood vessels lying adjacent to the sensory route of the maxillary [V2] and mandibular [V3] nerves may be involved. If symptoms persist and are unresponsive to medical care, surgical exploration of the trigeminal nerve (which is not without risk) may be necessary to remove any aberrant vessels. In the clinic The scalp has an extremely rich blood supply from the external carotid arteries, so lacerations of the scalp tend to bleed profusely. Importantly, scalp bleeding is predominantly arterial, because of two reasons. First, in the erect position the venous pressure is extremely low. Second, the vessels do not retract and close when lacerated because the connective tissue in which they are found holds them open. In the clinic


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Anatomy_Gray. In the clinic Fractures of the orbit are not uncommon and may involve the orbital margins with extension into the maxilla, frontal, and zygomatic bones. These fractures are often part of complex facial fractures. Fractures within the orbit frequently occur within the floor and the medial wall; however, superior and lateral wall fractures also occur. Inferior orbital floor fractures are one of the commonest types of injuries. These fractures may drag the inferior oblique muscle and associated tissues into the fracture line. In these instances, patients may have upward gaze failure (upward gaze diplopia) in the affected eye. Medial wall fractures characteristically show air within the orbit in radiographs. This is due to fracture of the ethmoidal labyrinth, permitting direct continuity between the orbit and the ethmoidal paranasal sinuses. Occasionally, patients feel a full sensation within the orbit when blowing the nose. In the clinic


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Anatomy_Gray. In the clinic Horner’s syndrome is caused by any lesion that leads to a loss of sympathetic function in the head. It is characterized by three typical features: pupillary constriction due to paralysis of the dilator pupillae muscle, partial ptosis (drooping of the upper eyelid) due to paralysis of the superior tarsal muscle, and absence of sweating on the ipsilateral side of the face and the neck due to absence of innervation of the sweat glands. Secondary changes may also include: ipsilateral vasodilation due to loss of the normal sympathetic control of the subcutaneous blood vessels, and enophthalmos (sinking of the eye)—believed to result from paralysis of the orbitalis muscle, although this is an uncommon feature of Horner’s syndrome. The orbitalis muscle spans the inferior orbital fissure and helps maintain the forward position of orbital contents.


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Anatomy_Gray. The orbitalis muscle spans the inferior orbital fissure and helps maintain the forward position of orbital contents. The commonest cause for Horner’s syndrome is a tumor eroding the cervicothoracic ganglion, which is typically an apical lung tumor. A surgically induced Horner’s syndrome may be necessary for patients who suffer severe hyperhidrosis (sweating). This often debilitating condition may be so severe that patients are confined to their home for fear of embarrassment. Treatment is relatively straightforward. The patient is anesthetized and a bifurcate endotracheal tube is placed into the left and right main bronchi. A small incision is made in the intercostal space on the appropriate side, and a surgically induced pneumothorax is created. The patient is ventilated through the contralateral lung.


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Anatomy_Gray. Using an endoscope the apex of the thoracic cavity can be viewed from inside and the cervicothoracic ganglion readily identified. Obliterative techniques include thermocoagulation and surgical excision. After the ganglion has been destroyed, the endoscope is removed, the lung is reinflated, and the small hole is sutured. In the clinic Examination of the eye Examination of the eye includes assessment of the visual capabilities, the extrinsic musculature and its function, and disease processes that may affect the eye in isolation or as part of the systemic process. Examination of the eye includes tests for visual acuity, astigmatism, visual fields, and color interpretation (to exclude color blindness) in a variety of circumstances. The physician also assesses the retina, the optic nerve and its coverings, the lens, and the cornea. The extrinsic muscles are supplied by the abducent nerve [VI], the trochlear nerve [IV], and the oculomotor nerve [III].


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Anatomy_Gray. The extrinsic muscles are supplied by the abducent nerve [VI], the trochlear nerve [IV], and the oculomotor nerve [III]. The extrinsic muscles work synergistically to provide appropriate and conjugate eye movement: lateral rectus—abducent nerve [VI], superior oblique—trochlear nerve [IV], and remainder—oculomotor nerve [III]. The eye may be affected in systemic diseases. Diabetes mellitus typically affects the eye and may cause cataracts, macular disease, and retinal hemorrhage, all impairing vision. Occasionally unilateral paralysis of the extra-ocular muscles occurs and is due to brainstem injury or direct nerve injury, which may be associated with tumor compression or trauma. The paralysis of a muscle is easily demonstrated when the patient attempts to move the eye in the direction associated with normal action of that muscle. Typically the patient complains of double vision (diplopia). Loss of innervation of the muscles around the eye


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Anatomy_Gray. Loss of innervation of the muscles around the eye Loss of innervation of the orbicularis oculi by the facial nerve [VII] causes an inability to close the eyelids tightly, allowing the lower eyelid to droop away causing spillage of tears. This loss of tears allows drying of the conjunctiva, which may ulcerate, so allowing secondary infection. Loss of innervation of the levator palpebrae superioris by oculomotor nerve [III] damage causes an inability of the superior eyelid to elevate, producing a complete ptosis. Usually, oculomotor nerve [III] damage is caused by severe head injury. Loss of innervation of the superior tarsal muscle by sympathetic fibers causes a constant partial ptosis. Any lesion along the sympathetic trunk can induce this. An apical pulmonary malignancy should always be suspected because the ptosis may be part of Horner’s syndrome (see “In the clinic” on p. 920). In the clinic The “H-test”