![]() However, unlike Argyll Robertson pupils, this finding is unilateral, and most patients also have anisocoria, ptosis, and diplopia. After damage to the third nerve (from trauma, aneurysms, or tumors, but not ischemia), regenerating fibers originally destined for the medial rectus muscle may instead reinnervate the pupillary constrictor, thus causing pupillary constriction during convergence but the absence of reaction to light. 4.Īberrant Regeneration of the Third Nerve. Common causes of the dorsal midbrain syndrome are pinealoma in younger patients and multiple sclerosis and basilar artery strokes in older patients. 21 Characteristic findings of the dorsal midbrain syndrome are light-near dissociation, vertical gaze palsy, lid retraction, and convergence-retraction nystagmus (a rhythmic inward movement of both eyes from cocontraction of the extraocular muscles, usually elicited during convergence on upward gaze many neuro-ophthalmologists use a optokinetic drum rotating downward to elicit the finding). ![]() 3.ĭorsal Midbrain Syndrome (Parinaud syndrome, Sylvian Aqueduct Syndrome, Pretectal Syndrome). However, in contrast to other causes of light-near dissociation, optic nerve and retinal disease severely impair vision. Either of these disorders may eliminate the light reaction when light is directed into the abnormal eye, although the pupils still constrict with the near synkinesis. Other causes of light-near dissociation include the following: 1. 40Īrgyll Robertson pupils display light-near dissociation (i.e., they fail to react to light but constrict during near vision). The lesion responsible for Argyll Robertson pupils is uncertain but may result either from a disturbance in the midbrain light-reflex pathway between the pretectal and Edinger–Westphal nuclei or from damage to the ciliary ganglia. ![]() However, it is nonspecific and may also be caused by diabetes. This pupillary abnormality is highly suggestive of syphilis and should therefore prompt serologic and fluorescent treponemal antibody absorption (FTA-ABS) testing. Technically, to have an Argyll Robertson pupil, the involved eye must have some vision, to ensure the light-near dissociation is not due to a deafferented pupil. The pupil does not react to light regardless of which eye is stimulated. Balcer, in Liu, Volpe, and Galetta's Neuro-Ophthalmology (Third Edition), 2019 Argyll Robertson PupilsĪrgyll Robertson pupils 38,39 also exhibit light-near dissociation with a brisk constriction during near viewing but typically are miotic, are slightly irregular, and dilate poorly in the dark ( Fig. An important differential diagnosis is miotic pupils after morphine administration: under these circumstances no light-near dissociation will be seen. ![]() Therefore, serological tests for syphilis are still recommended in all patients presenting with pupils that look like Argyll Robertson pupils ( Thompson and Kardon, 2006). Thompson (1979) found that, in some cases of bilateral tonic pupils, fluorescent treponema antibody absorption tests were positive. We therefore consider Argyll Robertson pupils not as an own entity but as long-standing tonic pupils. Many end up as very small pupils, hardly distinguishable from what is classically named Argyll Robertson pupil. ![]() Bilateral tonic pupils become more common in older age and a tonic pupil tends to become narrow after some years ( Thompson et al., 1979a). All conditions that resembled Argyll Robertson pupils clinically could eventually be diagnosed as long-standing tonic pupils. However, we have not seen typical Argyll Robertson pupils – narrow pupils unreactive to light but reactive to near vision – with positive serological findings for syphilis for more than 20 years. Helmut Wilhelm, in Handbook of Clinical Neurology, 2011 Argyll Robertson pupilĪrgyll Robertson pupil is ascribed to a lesion of intercalated neurons in the midbrain or to damage of inhibitory fibers to the oculomotor nucleus ( Loewenfeld, 1969). ![]()
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