10.14639/0392-100X-N2143
Objective. To describe a clear and intuitive way to analyse the anatomical meaning of images observed in Drug-induced Sleep Endoscopy (DISE) to fully understand the obstructive dynamics and therefore opt for a tailor-made pharyngeal surgical technique.Methods. From January 2016 to December 2020, 298 patients who underwent DISE were selected according to inclusion criteria.Results. The case series consisted of 204 males and 94 females with a mean age of 56 years. Body mass index ranged from 19 kg/m2 to 34 kg/m2 with a median of 26.5 kg/m2. Median Apnoea-Hypopnea Index (AHI) was 27 (range 5-62.3). The authors also observed four palate pharyngeal phenotypic patterns of collapse and clarify the morphology and role of the main muscles involved in upper airway collapse.Conclusions. DISE is fundamental to determine the collapse site in patients affected by obstructive sleep apnoea syndrome. The velopharyngeal region is the most common site of obstruction and lateral pharyngeal wall collapse is the major determining factor. DISE can lead to a deeper understanding of the obstructive dynamic patterns and a more precise identification of the muscle bundles responsible for upper airway collapse.
text/xml
1827-675X
2143
en
Ingrid Raponi
http://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
palatopharyngeal muscles
Role of functional and anatomic study in sleep endoscopy for treatment of OSA
Text.Serial.Journal
https://www.actaitalica.it/
42
OSAHS
2022-12-29
2022-05-05
2022-12-29
2023-01-16
554-559
1
Ingrid Raponi
2022/12/29
10.14639/0392-100X-N2143
554
Department of Maxillo Facial Surgery, F. Spaziani Hospital, ASL Frosinone, Italy
1827-675X
palatopharyngeal muscles
en
559
Role of functional and anatomic study in sleep endoscopy for treatment of OSA
https://www.actaitalica.it/article/download/2143/895
42
ACTA OTORHINOLARYNGOLOGICA ITALICA 2022;42:554-559; doi: 10.14639/0392-100X-N2143




OSAHS


Role of functional and anatomic study in sleep
endoscopy for treatment of OSA
Ruolo dello studio funzionale e anatomico durante la sleep endoscopy nella terapia
delle OSAS
Andrea Marzetti1,2, Caterina Tripodi1, Ingrid Raponi2
1
 Department of Otolaryngology Head and Neck Surgery, F. Spaziani Hospital, ASL Frosinone, Italy; 2 Department of Maxillo Facial
Surgery, F. Spaziani Hospital, ASL Frosinone, Italy


SUMMARY
Objective.To describe a clear and intuitive way to analyse the anatomical meaning of im-
ages observed in Drug-induced Sleep Endoscopy (DISE) to fully understand the obstructive
dynamics and therefore opt for a tailor-made pharyngeal surgical technique.
Methods. From January 2016 to December 2020, 298 patients who underwent DISE were
selected according to inclusion criteria.
Results. The case series consisted of 204 males and 94 females with a mean age of 56
years. Body mass index ranged from 19 kg/m2 to 34 kg/m2 with a median of 26.5 kg/m2.
Median Apnoea-Hypopnea Index (AHI) was 27 (range 5-62.3). The authors also observed
four palate pharyngeal phenotypic patterns of collapse and clarify the morphology and role
of the main muscles involved in upper airway collapse.
Conclusions. DISE is fundamental to determine the collapse site in patients affected by
obstructive sleep apnoea syndrome. The velopharyngeal region is the most common site
of obstruction and lateral pharyngeal wall collapse is the major determining factor. DISE
can lead to a deeper understanding of the obstructive dynamic patterns and a more precise
identification of the muscle bundles responsible for upper airway collapse.
KEY WORDS: barbed sutures, OSA surgery, palatal surgery, drug induced sleep endoscopy,
palatopharyngeal muscles
                                                                                                Received: May 5, 2022
                                                                                                Accepted: August 15, 2022
RIASSUNTO
Obiettivo. Descrivere in modo chiaro e intuitivo il significato anatomico delle immagini        Correspondence
osservate durante la Sleep Endoscopy (DISE) per comprendere appieno la dinamica ostrut-         Ingrid Raponi
tiva e per poter poi indirizzare la scelta terapeutica verso una chirurgia personalizzata.      Department of Maxillo Facial Surgery, F. Spaziani
Materiali e metodi. Da gennaio 2016 a dicembre 2020, 298 pazienti sottoposti a Sleep            Hospital, ASL Frosinone, via Armando Fabi snc,
Endoscopy sono stati selezionati, sulla base di criteri di inclusione.                          03100 Frosinone, Italy
Risultati. I pazienti inseriti nello studio erano 204 maschi e 94 femmine con un’età me-        Fax 07751883361
dia di 56 anni. L’indice di massa corporea variava da 19 kg/m2 a 34 kg/m2 con un valore         E-mail: Ingrid.raponi@aslfrosinone.it
mediano di 26,5 kg/m2. L’indice di apnea-ipopnea (AHI) medio era di 27 (range 5-62,3).
Gli autori hanno anche osservato quattro modelli fenotipici di collasso del palato e chia-        How to cite this article: Marzetti A, Tripodi C,
riscono la morfologia e il ruolo dei principali muscoli coinvolti nel collasso dell’UA.           Raponi I. Role of functional and anatomic study
Conclusioni. La DISE è fondamentale per determinare il sito di collasso nei pazienti af-          in sleep endoscopy for treatment of OSA. Acta
fetti dalla sindrome dell’apnea ostruttiva del sonno (OSA). La regione velofaringea è il sito     Otorhinolaryngol Ital 2022;42:554-559. https://
                                                                                                  doi.org/10.14639/0392-100X-N2143
più comune di ostruzione e il collasso laterale della parete faringea è il principale fattore
determinante. La DISE può portare a una comprensione più profonda dei modelli dinamici
                                                                                                © Società Italiana di Otorinolaringoiatria
ostruttivi e a un’identificazione più precisa dei fasci muscolari responsabili del collasso     e Chirurgia Cervico-Facciale
delle vie aeree superiori.
PAROLE CHIAVE: sutura barbed, chirurgia dell’OSAS, chirurgia palatale, sleep                                   OPEN ACCESS
endoscopy, muscoli palatofaringei                                                               This is an open access article distributed in accordance with
                                                                                                the CC-BY-NC-ND (Creative Commons Attribution-Non-
                                                                                                Commercial-NoDerivatives 4.0 International) license. The
                                                                                                article can be used by giving appropriate credit and mentio-
                                                                                                ning the license, but only for non-commercial purposes and
                                                                                                only in the original version. For further information: https://
                                                                                                creativecommons.org/licenses/by-nc-nd/4.0/deed.en




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                                                                  The anatomo-functional approach to palatal-pharyngeal collapses for a tailored OSA’s surgery




Introduction                                                                       more precise identification of the muscle bundles respon-
                                                                                   sible for UA collapse, thus enabling more targeted thera-
Obstructive sleep apnoea (OSA) syndrome is a respira-
                                                                                   peutic and surgical planning 7. The purpose of this work is
tory sleep disorder characterised by partial or complete
                                                                                   to clarify the morphology and role of the main muscles in-
recurrent episodes of upper airway collapse which occur
                                                                                   volved in UA collapse. Furthermore, the authors propose a
during the night. Although multilevel collapses of the up-
per airways (UA) are not rare, the velopharyngeal region                           clear and intuitive way to analyse the anatomical meaning
is believed to be the most common site of obstruction,                             of images observed in DISE. A clear description of known
with lateral pharyngeal wall collapse as the major deter-                          anatomical structures, such as the palatal muscles, lateral
mining factor 1. It is widely accepted that Drug-induced                           palatal wall and pharyngeal airway phenotypes, enables a
Sleep Endoscopy (DISE) is fundamental to determine the                             better understanding of obstructive dynamics and patterns
collapse site and select the most appropriate therapeutic                          observed in DISE and to subsequently opt for a tailored
strategy 2,3. Moreover, also thanks to sleep endoscopic ob-                        pharyngeal surgical technique. Muscle bundles composing
servation, pharyngeal surgical techniques have undergone                           the soft palate are tensor veli palatini and its aponeurosis
a rapid evolution shifting from uvulopalatopharyngoplasty                          (TVP), salpingopharyngeus muscle (SP), palatopharyn-
(UPPP) 4 towards the latest surgical techniques of lateral                         geus muscle (PP), palatoglossus muscle (PG), levator veli
pharyngoplasty such as custom-made barbed technique 5,6.                           palatini (LVP), muscle of the uvula (UV), superior pharyn-
Dynamic assessment during DISE can lead to a deeper                                geal constrictor muscle (SC) 4 (Fig. 1). The muscular sling,
understanding of the obstructive dynamic patterns and a                            serving as the margin of the retropalatal lateral pharyngeal




Figure 1. Muscles of the palatopharyngeal complex. (A) lateral view; (B) anterior view; (C) posterior view; (D) figure legend.



                                                                                                                                                        555
A. Marzetti et al.




wall, is the SP proximally and the PP distally 8. The TVP at-   The purpose of this study is to correlate endoscopic im-
taches to the palatine aponeurosis from its origin at the me-   ages of DISE with anatomical muscle structures in order to
dial pterygoid plate of the sphenoid and lateral wall of the    design a mini-invasive and customised surgical procedure.
Eustachian tube and runs postero-lateral to the hamulus.
Its function is to open the Eustachian tube and to tense the    Materials and methods
soft palate during swallowing. The SP originates from the
cartilaginous part of auditory (Eustachian) tube and its in-    From January 2016 to December 2020, we selected 298
sertion blends with dorsal bundle of the longitudinal part of   patients who underwent DISE.
the palatopharyngeus muscle. The muscle extends through         Inclusion criteria were age > 20 years and < 72 years, body
the salpingopharyngeal fold and elevates the lateral phar-      mass index (BMI) < 34, simple snoring or apnoea-hypo-
yngeal walls, opening the auditory tube during swallow-         pnoea index (AHI) > 5 as documented by polysomnogra-
ing. The PP muscle originates from the palatal aponeurosis      phy and no prior surgical intervention for sleep apnoea.
as three separated fascicles that inferiorly combine into a     All examinations were conducted with a flexible rhino-
unique muscle and it is composed of two major divisions:        laryngoscope introduced in one of the nasal cavities and
the longitudinal PP and the transverse PP. The longitudinal     subsequently in the mouth. The endoscopic system was
fascicle consists in a ventral (or medial) and a dorsal (or     always equipped with an audio-video recording system.
lateral) bundle that hug the LVP before combining into a        The desired deepness sleep level was generally reach and
more concise muscle bundle within the palatopharyngeal          maintained by propofol intra-venous infusion using target-
arch and lateral wall of the pharynx. Dorsal and ventral        controlled infusion (TCI).
bellies of PP muscle lie medial to the SC in the orophar-       A Bispectral Index (BISTM) device has generally been used
ynx before inserting on the thyroid cartilage and diffus-       to obtain a numerical instrumental support in evaluation of
ing into fibres of the inferior constrictor muscle 9. The PP    the level of sedation of patients. However, the presence or
muscle shrinks during swallowing medializing both the           absence of this monitoring, as well as the TCI, were not
lateral walls 10. Anatomically, it may function as an air-      considered inclusion criteria in this study. At least two skill
way constrictor or dilator depending on the resting posi-       sleep surgeons and one anesthesiologist were present at all
tion of the muscle. The transverse fascicle contributes to      DISE investigations.
the nasopharyngeal sphincter to separate the oropharynx
from the nasopharynx. Moreover, it seems that the mus-          Results
cle length of the paired transverse fasciculi contributes to
maximize retropalatal airspace size. The PG muscle pulls        Case series
the soft palate towards the tongue. It arises from the in-      We collected data on a sample of 298 patients for whom
ferior edge of palatine aponeurosis and travels within the      the recording of a fully satisfactory sleep phase was ob-
palatoglossal fold to attach into the side of the tongue 8.     tained in terms of probable reproduction of natural sleep
The PG also separates the superior pole of the tonsil from      characteristics: 204 males and 94 females with a mean age
the “supratonsillary fat” 11. The LVP muscle come from          of 56 years. BMI ranged from 19 kg/m2 to 34 kg/m2 with
the inferior aspect of the Eustachian tube cartilage and the    a median value of 26.5 kg/m2. Based on preoperative poly-
petrous temporal bone, enters the soft palate and runs to       somnography, our sample was classified as follows: 18 pa-
the midline. It is distributed within the nasal side of the     tients had simple snoring and 280 patients presented with
soft palate and attached to the inferior surface of the fas-    OSHAS; median AHI was of 27 (range 5-62.3).
cia and aponeurosis with the function of elevating the soft     Based on DISE data, we observed three palate pharyngeal
palate against the posterior pharyngeal wall during swal-       phenotypic patterns already recognised in the literature
lowing to prevent the entry of food into the nasopharynx.       and, additionally, a fourth (Fig. 2):
The SC muscle constitutes grossly the lateral and posterior     1. in the pure antero-posterior palatal collapse the mus-
boundary of the pharynx. Muscle bundles originate from             cles that seem to be involved are the Levator Veli Palatini
the buccinators, maxilla, pterygomandibular raphe, and             (LVP), Palatopharyngeus (PP) and Uvula (UV);
tongue to insert posteriorly into the midline where it re-      2. transverse collapses are most likely attributable to the
lates to the pharyngobasilar fascia 7. The UV functions to         hyperkinetic action of the ventral and dorsal fascicles of
shorten the uvula; it derives from the palatine aponeurosis        the longitudinal portion of the PP. In case of transverse
and the posterior nasal spine and attaches to the mucous           collapse, one must distinguish between nasopharyngeal
membrane of the uvula. Ipsilateral contraction of the mus-         origin and oropharyngeal origin. In the first case, the
culus uvulae muscle draws up the uvula on the same side.           causal factor is the hyperkinetic action of the LVP and



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                                                                   The anatomo-functional approach to palatal-pharyngeal collapses for a tailored OSA’s surgery




                                                                                      the sum of both the pure antero-posterior and transverse
                                                                                      collapses.
                                                                                   In all patients, a clear velopharyngeal collapse was ob-
                                                                                   served in DISE with different patterns: 54 pure antero-pos-
                                                                                   terior, 93 transversal, 72 sphincteric and 79 triple vector
                                                                                   collapses. In 72 patients, the antero-posterior component of
                                                                                   the velopharyngeal collapse was evaluated as a result of the
                                                                                   retropulsion of the dorsum of the tongue.
                                                                                   In 26% of patients, it was possible to completely resolve the
                                                                                   collapse with a chin lift or mandibular suspension manoeu-
                                                                                   vre. In these cases, resolution was subjectively evaluated as
                                                                                   a resumption of ventilation phases without significant sound
                                                                                   production. In 78 patients potentially candidate to treatment
                                                                                   with a Mandibular Advancement Device (MAD), a George
                                                                                   Gauge device was used to record the resolving jaw position.
                                                                                   In 48% of cases, applying a greater force in mandibular ad-
                                                                                   vancement, it was possible to obtain only a partial resolution
                                                                                   of the collapse with an interruption of apnoea but a persisting
                                                                                   a strong sound vibration of the velopharyngeal structures.

                                                                                   Discussion
                                                                                   The complete anatomic and functional description of the
                                                                                   palato-pharyngeal unit should include a deep understand-
                                                                                   ing of the dynamics created when the muscles work simul-
                                                                                   taneously and a correct interpretation of specificity for each
                                                                                   patient. To date, we believe that DISE provides the most
                                                                                   useful information of upper airway collapse during sleep
                                                                                   compared to other evaluation techniques available (e.g.,
                                                                                   awake fibroendoscopy, Muller’s manoeuvre) especially re-
                                                                                   lated to the tongue and epiglottis collapse 12. In fact, the use
                                                                                   of transoral and trans-nasal fiber-optic endoscopic during
  V: Velum; PPW: posterior pharyngeal wall; LPW: lateral pharyngeal wall; PP:
  palatopharyngeus muscle; SP: salpingopharyngeus muscle                           DISE, in association with the mandibular pull up and chin
                                                                                   lift manoeuvre, enables to more clearly understand the role
Figure 2. Vectorial classification of palatopharyngeal collapse patterns.          of the tongue. In particular, the degree of tongue retraction
                                                                                   and position highlights a secondary anteroposterior soft
                                                                                   palate collapse (Fig. 3). Moreover, DISE has been dem-
   SP muscle. The latter in almost all cases continues with                        onstrated to be useful in predicting satisfactory outcomes
   the action of the ventral fascicles of the longitudinal por-                    in intraoral devices users and in understanding ventilatory
   tion of the palatopharyngeal muscle;                                            therapy failures. Finally, in case of non-responders to sur-
3. the sphincteric collapse at the Passavant ridge, accord-                        gery, DISE provides insights to the residual causes of UA
   ing to the anatomical findings by Sumida 10, originates                         collapse, addressing further therapeutic strategies 2,3,5,7.
   by the simultaneous action of the superior constrictor of                       Many surgical techniques have been described in the mod-
   the pharynx and the transverse fasciculus of the PP mus-                        ern evolution of OSA surgery and mostly contain the same
   cle that unfolds the latter at the transition point between                     fundamental concepts: preservation of soft palate and ton-
   the nasopharynx and the oropharynx;                                             sillar pillars mucous margins, preservation of the function
4. triple vector collapses in which the lumen narrows in a                         of the uvula, concept of rigid anchoring structures, muscle
   triangular manner by the concomitance of two transverse                         transposition and tensioning, slow resorption self-locking
   vectors and one anteroposterior which are attributable to                       sutures and muscle vectors.
   the simultaneous but non-uniform action of the previous                         In the literature, it is well established that DISE, in addition
   structures (LVP, TLV, PP, SC). Actually, this collapse is                       to being a dynamic, safe and easy to perform technique that



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A. Marzetti et al.




                                                                                      Figure 4. How to achieve an eclectic approach to OSA surgery.


                                                                                      To our knowledge this is the first study establishing a link
                                                                                      between detailed anatomical description and characterisa-
                                                                                      tion of muscle bundles to the dynamics observed in DISE
                                                                                      during collapse patterns.

                                                                                      Conclusions
                                                                                      In conclusion, DISE is the most important diagnostic tool
                                                                                      to study anatomic-functional dynamics. DISE enables
Figure 3. Secondary palate collapse. (A) no secondary collapse; (B) partial           identification of the collapse pattern of soft palate, pharyn-
palatal collapse; (C) total palatal collapse (TPC); (D) TPC with palatal elevation.   geal lateral wall collapse, epiglottic trapdoor phenomenon,
                                                                                      secondary epiglottic collapse and involvement of ary-ep-
                                                                                      iglottic folds. In our experience, the study about the role
allows visualisation of the anatomical sites of vibration or                          of functional and anatomic dynamics in sleep endoscopy
collapse, can lead to patient-tailored treatment 8.                                   for treatment of OSA is important and represents the first
Following the conclusions of Ravesloot and De Vries 13 and                            step in a mini-invasive, personalised, eclectic and anatomy-
taking to an extreme the evolutionary concept of a patient-                           driven use of barbed surgery with reduced damage to ana-
tailored approach, we can affirm that DISE allows identi-                             tomical structures (Fig. 4).
fication of the collapse pattern severity and understand the
muscular structures responsible, thus enabling to selective-                          Acknowledgements
ly intervene only on those structures, changing the force                             The authors thank the illustrator Chiara Donateo for her
vector of involved muscles. In our experience, we have                                collaboration and the production of anatomical images. Im-
achieved good surgical success in sphincter collapse with                             ages are kindly provided by ASSUT EUROPE srl.
lateral pharyngoplasty. In this study, we introduce trivecto-                         Authors have nothing else to disclose.
ral collapse, which requires both an anterior palatoplasty
and lateral pharyngoplasty to resolve the obstruction and                             Conflict of interest statement
vibration. In fact, in a small percentage of patients with                            The authors declare no conflict of interest.
severe OSAS and trivectoral collapse treated with lateral
pharyngoplasty and/or anterior palatoplasty alone, we ob-                             Funding
served the persistence of a vibratory and/or obstructive site                         This research did not receive any specific grant from funding
with the untreated vector in postoperative DISE.                                      agencies in the public, commercial, or not-for-profit sectors.



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Author contributions                                                         5
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                                                                                  a targeted approach. Medicina (Kaunas) 2021;57:690. https://doi.
AM: work design, first operator, final revision. CT: acquisi-                     org/10.3390/medicina57070690
tion, analysis, and interpretation of data, draft manuscript                 6
                                                                                  Vicini C, Hendawy E, Campanini A, et al. Barbed reposition phar-
preparation. IR: draft manuscript preparation, analysis of                        yngoplasty (BRP) for OSAHS: a feasibility, safety, efficacy and
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                                                                                  Kotecha B, De Vito A. Drug induced sleep endoscopy: its role in eval-
                                                                                  uation of the upper airway obstruction and patient selection for surgi-
                                                                                  cal and non-surgical treatment. J Thorac Dis 2018;10(Suppl 1):S40-
Ethical consideration                                                             S47. https://doi.org/10.21037/jtd.2017.10.32
The present work is a retrospective study and DISE is a                      8
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