RELATIVE AFFERENT PUPIL DEFECT:

The afferent pupil defect is the dilation of the pupil in the both eyes when the light is swung from the normal eye over to the defective one. This is due to poor transmission of the light to the brain via a damaged optic nerve. The brain perceives the same stimulus as having a decreased intensity and dilates both pupils.

It is a relative defect, hence there has to be a difference in the function between the two eyes for it to be detectable. If both eyes are functioning poorly, there will not be an relative afferent pupillary defect. There has to be extensive retinal or optic nerve damage for an RAPD to be demonstrable.



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Note added at 8 mins (2007-10-26 13:42:39 GMT)
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عيب نقل نسبية الضوء في العين
في بؤبؤ العين

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Note added at 8 mins (2007-10-26 13:43:16 GMT)
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http://eyelearn.med.utoronto.ca/Lectures04-05/NeuroOphth/15R...

الاضطراب / الاختلال النسبي للقوس الواردة لمنعكس الحدقة للنور
http://www.arabspine.com/روابط/العمودالفقريوالحبلالشوكي/اضطر...

أو
الأختلال النسبي في الطريق الوارد للمنعكس الحدقي

http://www.hakeem-sy.org/main/node/8023

والله أعلم

useful link
http://www.mrcophth.com/pupils/rapd.html