The Pupil in Clinical Diagnosis

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Identifier 19800220_nanos_varsubjectssympos1_05
Title The Pupil in Clinical Diagnosis
Creator Zweifel, Thomas J; Thompson, H Stanley
Subject Pupil in Clinical Diagnosis; Pupil Anatomy; Efferent Pupil Defects; Light-Near Dissociation; Horner's Syndrome; Unequal Pupils
Description The muscle fibers in the iris which regulate pupil size are innervated by sympathetic and parasympathetic divisions of the autonomic nervous system. The sphinctel; a 1 mm circular band at the pupillary margin, is under parasympathetic control and is activated in response to light stimuli or during accommodation (near response). Afferent fibers for redex pupil constriction ~ light originate in the retina and run parallel to visual afferents in the optic nerve (Figure 1). Approximately 53% of light reflex afferents cross the optic chiasm to travel in the contralateral optic tract, whereas 47% remain ipsilateral. The pupil afferents leave the optic tract in its posterior one-third to enter the midbrain and synapse in the pretectal nucleus. Fibers then hemidecussate around the sylvianaqueduct and innervate each Edinger-Westphal nucleus. This hemidecussation provides essentially equal afferent drive from each eye to each Edinget Westphal nucleus.
Relation is Part of NANOS 1980: Various Subjects Symposium (Session 1)
Publisher Spencer S. Eccles Health Sciences Library, University of Utah
Date 1980-02-20
Type Text
Format application/pdf
Format Creation application/pdf
Source 1980 North American Neuro-Ophthalmology Society Annual Meeting
Rights Management Copyright 1980. For further information regarding the rights to this collection, please visit:
Holding Institution North American Neuro-Ophthalmology Association. NANOS Executive Office 5841 Cedar Lake Road, Suite 204, Minneapolis, MN 55416
Collection Neuro-ophthalmology Virtual Education Library: NOVEL
Language eng
ARK ark:/87278/s64203s0
Setname ehsl_novel_nam
Date Created 2014-06-03
Date Modified 2021-05-06
ID 183782
Reference URL
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