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16K views 2 replies 3 participants last post by  Kaus  
#1 ·
Argyll-Robertson Pupil features
Argyll Robertson Pupil (ARP)
Read it from front to back: it is
ARP, standing for Accomodation Reflex Present.

Read it from back to front: it is
PRA, standing for Pupillary Reflex Absent. ;)
 
#3 ·
Re: Op

I would like to add that the pathophysiology of Argyll Robertson pupil is because of the central dissociation of the pathways of the two reflexes, the pupillary light reflex and the accommodation reflex. The pretectal nucleus is part of the pupillary light reflex, but it is not part of the accommodation reflex, this area is damaged by siphilis, so there will be no pupillary constriction in response to light, but pupillary constriction can still happen through the accommodation reflex because the accommodation reflex does not require the presence of the pretectal area in order to complete the pathway for constriction. :)