Pupillary Light Reflex and Afferent Pathway

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What is the location of the pretectal nucleus in the midbrain?

At the level of the superior colliculus (correct)

At the level of the inferior colliculus

At the level of the pons

At the level of the medulla oblongata

What type of nerve fibers exit the midbrain with CNIII?

Postganglionic parasympathetic fibers

Preganglionic sympathetic fibers

Postganglionic sympathetic fibers

Preganglionic parasympathetic fibers (correct)

Which cranial nerve is responsible for causing both pupils to constrict in response to light?

Cranial Nerve VI (Abducens Nerve)

Cranial Nerve II (Optic Nerve)

Cranial Nerve III (Oculomotor Nerve) (correct)

Cranial Nerve IV (Trochlear Nerve)

How many neurons are involved in the afferent pathway of the pupillary light reflex?

Four neurons Signup and view all the answers

What is the location of the ciliospinal center of Budge?

C8-T2 Signup and view all the answers

What type of muscle is innervated by the 4th neuron arc in the afferent pathway of the pupillary light reflex?

Sphincter muscle Signup and view all the answers

What is the purpose of the swinging flashlight test or Marcus Gunn test?

To diagnose an afferent pupillary defect (APD) Signup and view all the answers

What is the normal response of the pupils during the swinging flashlight test?

Both pupils constrict equally and re-dilate slightly when either eye is stimulated Signup and view all the answers

What is the characteristic of an affected eye in an afferent pupillary defect (APD)?

Its consensual reaction > direct reaction Signup and view all the answers

What is a common error in APD testing?

Swinging the flashlight too slowly Signup and view all the answers

What is the grading scale for the speed of pupil reaction?

0-4, with 0 being none and 4 being brisk Signup and view all the answers

What is the purpose of the distance target in the swinging flashlight test?

Not mentioned in the text Signup and view all the answers

What is the site of lesion in Argyll Robertson pupil?

Sylvian aqueduct in the rostral midbrain Signup and view all the answers

What is the characteristic feature of Adie's tonic pupil?

Unilateral or bilateral tonically reacting pupils Signup and view all the answers

What is the cause of Adie's tonic pupil?

Denervation of the postganglionic nerve supply to the sphincter and ciliary muscle Signup and view all the answers

What is a common finding on slit lamp examination of Adie's tonic pupil?

Sectoral palsy with vermiform movements of the margin Signup and view all the answers

What is a characteristic of the affected pupil in Adie's tonic pupil?

It is abnormally dilated with sluggish reaction to light Signup and view all the answers

What is the name of the muscle that is primarily paralyzed in Horner's Syndrome, leading to ptosis?

Muller's muscle Signup and view all the answers

What is the term for the condition where the lower lid is slightly elevated due to loss of nerve supply in Horner's Syndrome?

Upside down ptosis Signup and view all the answers

What is the characteristic of anisocoria in Horner's Syndrome?

More pronounced in dark Signup and view all the answers

Which type of Horner's Syndrome is not associated with anhidrosis?

Postganglionic Horner's Syndrome Signup and view all the answers

What is a common cause of preganglionic Horner's Syndrome?

Lung tumor Signup and view all the answers

What is a characteristic of congenital Horner's Syndrome?

Iris depigmentation Signup and view all the answers

What is the primary concern when managing isolated III CN palsy with pupil involvement?

Ruling out PCA aneurysm Signup and view all the answers

What is the recommended follow-up for patients with ischemic III CN palsy with pupillary sparing?

F/U in 5-7 days Signup and view all the answers

What is the indication for ordering neuro testing in patients with III CN palsy?

Age less than 50 years old Signup and view all the answers

What is the most common cause of isolated III CN palsy?

Ischemic microvascular disease Signup and view all the answers

What is the recommended management for patients with III CN palsy with pupillary sparing and a known vascular condition?

Follow the patient closely and monitor for possible pupillary involvement Signup and view all the answers

What is the significance of pupillary sparing in III CN palsy?

Is often associated with diabetes or hypertension Signup and view all the answers