Abnormal pupillary responses can provide valuable diagnostic information in various medical conditions, including neuro-ophthalmic disorders, systemic diseases and drug effects.
Knowledge of abnormal pupillary responses is crucial for medical professionals appearing for NEET PG as it forms an important part of the ophthalmology section in the exam.
Read this blog and get a quick overview of this important Ophthalmology topic.
Argyll Robertson Pupil
B/L, constricted, irregular pupils
Seen in neurosyphilis, tertiary syphilis
Does not constrict to light but to near vision (because lesion is in dorsal midbrain damaging the light fibers but accommodation center is spared)
A/k/a Prostitute’s pupil (because it accommodates but no reaction)
ARP
Adie’s Pupil
Seen in young women (80%)
Seen after viral fever
U/L dilatation of pupil
Virus attacks ciliary ganglion, CN III is present in ciliary ganglion which gets affected causing
Parasympathetic constrictor fibres of pupil to damage, so no constriction
Unopposed sympathetic dilation of pupil occurs
Vermiform movement of iris (sluggish moment)
No reaction to light & Accommodation reflex positive (aberrant regeneration: fibers innervating ciliary body i.e., III nerve fibers and parasympathetic fibers also innervate pupil, but the fibers innervating ciliary body is 30% than the pupil therefore after damage, there is regeneration in ciliary body. Ciliary body fibers goes into aberrant mode & goes to pupil which is why it constricts so strongly to near objects but no reaction to light)
Argyll Robertson pupil
Adie’s pupil
Constricted pupil
B/L
Dilated pupil
U/L
Adie’s Test
Confirmed by pilocarpine challenge test
0.125% pilocarpine solution used, put in both eyes
Normal pupil does not constrict because solution is very dilute
Seen in anterior vision pathway (i.e. optic disc, optic nerve just before optic chiasma) disorders like optic neuritis (M/C), AION, optic nerve glioma
Tested by swinging torch light test
Take a torch and flash it into normal eye and observe: Pupil constricts in both eyes
When light is flashed into the affected eye: Pupil dilates in that eye because of nerve fibre damage.
Hutchinson’s Pupil
Seen in case of post head trauma leading to cerebral compression because of progressive intracranial haemorrhage
Consists of 3 stages
Stage 1: Pupil of the side of trauma constricts (due to irritation of oculomotor nerve which carry parasympathetic fibres)→ Normal side unaffected
Stage 2 (6 hrs. later): Due to progressive intracranial hemorrhage pupil of the injured side become dilated (parasympathetics are lost so unopposed sympathetic dilatation) → Normal pupil constricts because by this time some blood has trickled to other hemisphere and cause irritation of 3rd nerve.
Stage 3 (after another 6 to 10 hrs): Pupil of both sides fully dilated because parasympathetic fibres of 3rd Nerve on both sides are lost.
HORNER’S SYNDROME
Aka Oculosympathetic paralysis
Triad of:
Ptosis
Miosis
Anhidrosis
Enophthalmos is:
Not a true enophthalmos, only apparent / pseudo (no actual sinking of eyeball).
Because of ptosis (upper lid falls down) and inferior tarsal muscle palsy (inferior lid comes up) causing narrowing of palpebral fissure.
Put drop of Apraclonidine in both eyes and observe the change in Pupil
HS Pupil dilates, normal doesn’t
Important Information
Cocaine test is not done now a days used
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