An afferent pupillary defect is an eye condition where one eye is less sensitive to light, and will not contract as sharply in response to light as the unaffected eye.
Causes A conduction defect in one optic nerve causes the afferent pupillary defect, but it does not account for unequal pupils, which is a separate entity that requires additional explanation if it occurs. The afferent pupillary defect (APD) is seen only in unilateral optic nerve disease. The response to this light reduction is the same as that in the first instance both pupils dilate to an appropriate amount. The afferent pupillary defect (Marcus Gunn pupillary escape phenomenon) depends on the light-reduction response that occurs in the presence of a conduction defect in the optic nerve. In attempting to demonstrate the afferent pupillary defect in a patient, the physician shines the light into each eye separately From Wikipedia, the free encyclopedia. Marcus Gunn pupil or relative afferent pupillary defect (RAPD) is a medical sign observed during the swinging-flashlight test whereupon the patient's pupils constrict less (therefore appearing to dilate) when a bright light is swung from the unaffected eye to the affected eye. The Marcus Gunn pupil is a relative afferent pupillary defect indicating a decreased pupillary response to light in the affected eye. In the swinging flashlight test, a light is alternately shone into the left and right eyes 1 No Relative Afferent Pupillary Defect: Both pupils constrict equally without evidence of pupillary re-dilation with the swinging flashlight test, except possibly for hippus. 2  Hippus refers to non-rhythmic fluctuations in pupillary size when there is a steady illumination. Other Causes of a Relative Afferent Pupillary Defect. 1  Amblyopia, if severe, can lead to a relative afferent pupillary defect. 2  Usually the visual acuity would be 20/400, or worse. 3  Cerebral vascular disease-Usually, it is an optic nerve disorder that leads to an RAPD, rather than an optic tract or visual cortex disorder. An afferent pupillary defect is an eye condition where one eye is less sensitive to light, and will not contract as sharply in response to light as the unaffected eye. This can be a sign of optic nerve damage, tumor, glaucoma, and a number of other eye issues. An afferent pupillary defect may be a sign of damage to the optic nerve. An afferent pupillary defect may be a sign of glaucoma or other eye conditions. The eyes of a healthy person normally dilate only when in dim light. Many patients are not aware they have an afferent pupillary defect until it is discovered during an eye exam 1 Moderate Relative Afferent Pupillary Defect: The affected pupil shows a stable or unchanged level of constriction, followed by dilation to a greater size. 2  Severe Relative Afferent Pupillary Defect: The affected pupil shows an immediate dilation to a greater size. Other Causes of a Relative Afferent Pupillary Defect. 1  Amblyopia, if severe, can lead to a relative afferent pupillary defect. 2  Usually the visual acuity would be 20/400, or worse. 3  Cerebral vascular disease-Usually, it is an optic nerve disorder that leads to an RAPD, rather than an optic tract or visual cortex disorder. 1 Amblyopia, if severe, can lead to a relative afferent pupillary defect. 2  Usually the visual acuity would be 20/400, or worse. 3  Cerebral vascular disease-Usually, it is an optic nerve disorder that leads to an RAPD, rather than an optic tract or visual cortex disorder. Other Causes of a Relative Afferent Pupillary Defect. 1  afferent pupillary defect. Afferent Pupillary Defect (APD) or Marcus-Gunn pupil is a condition of the eye where the pupil doesn't dilate appropriately to the level of light reaching it. This will often result in one pupil appearing larger than the other (relative afferent pupillary defect-RAPD). This person with APD is often unaware of it except by looking in a mirror. There are many causes of APD including Optic Neuritis (ON) , glaucoma and optic nerve tumor.
http://www.cybersight.org/bins/volume_page.asp?cid=1-2630-2644-2654 https://en.wikipedia.org/wiki/Marcus_Gunn_pupil http://www.richmondeye.com/clinical-content-the-relative-afferent-pupillary-defect/ http://www.wisegeek.com/what-is-afferent-pupillary-defect.htm http://www.richmondeye.com/clinical-content-the-relative-afferent-pupillary-defect/ http://www.richmondeye.com/clinical-content-the-relative-afferent-pupillary-defect/ http://www.mult-sclerosis.org/afferentpupillarydefect.html
what is afferent pupillary defect