#41. Pupil - general data. Normal reactions of the pupil. Abnormal reactions of the pupil.

Question 1

What are the FUNCTIONS of the PUPIL?

Answer 1

• CENTRAL OPENING in the IRIS
• Acts as an APERTURE to IMPROVE QUALITY of RESULTING IMAGE
• By CONTROLLING the AMOUNT of Light that enters the eye

Question 2

What are the 3 NORMAL REACTIONS of the Pupil?

Answer 2

1) Light Reflex

2) Near Reflex

3) Psychosensory Reflex

Question 3

What is the LIGHT Reflex?

Answer 3

• When light is shone in 1 eye, BOTH pupils constrict

a. Eye that’s exposed to light = Direct Light Reflex

b. Other Eye responding = Consensual Light Reflex

• Rods + Cones INITIATE the LIGHT Reflex

Question 4

What is the NEAR Reflex?

Answer 4

• Occurs when looking at a NEAR Object

a. CONVERGENCE Reflex = Pupil Contraction on Convergence

b. ACCOMMODATION Reflex = Pupil Contraction associated with accommodation

Question 5

What is PSYCHOSENSORY Reflex?

Answer 5

DILATION of Pupil, in response to SENSORY / PSYCHIC Stimuli

Question 6

What are the 6 ABNORMALITIES of PUPILLARY REACTIONS?

Answer 6

1) Amaurotic Light Reflex

2) Efferent Pathway Defect

3) Wernicke’s Hemianopic Pupil

4) Marcus Gunn Pupil

5) Argyll Robertson Pupil

6) Adie’s Tonic Pupil

Question 7

What is the AMAUROTIC Light Reflex?

Answer 7

• ABSENCE of DIRECT Light Reflex on the AFFECTED side AND CONSENSUAL Side
• Indicating LESIONS on OPTIC NERVE / RETINA on the AFFECTED side
• Leading to COMPLETE BLINDNESS

Question 8

What is EFFERENT PATHWAY DEFECT?

Answer 8

ABSENCE in BOTH Direct / Consensual Light Reflex on the AFFECTED eye

BUT PRESENCE of BOTH Direct / Consensual Light Reflex on the Normal eye

DUE to
- Parasympatholytic Drugs = Atropine

Question 9

What is WERNICKE’s HEMIANOPIC PUPIL?

Answer 9

• LESION of OPTIC TRACT
• The LIGHT Reflex is ABSENT when light is shone of TEMPORAL Side of AFFECTED RETINA

Question 10

What is the MARCUS GUNN PUPIL?

Answer 10

PARADOXICAL RESPONSE to Pupil of Light

Test = Swinging Flash Light

Question 11

What is the ARGYLL ROBERTSON PUPIL?

Answer 11

• Small Pupil
• ABSENT Light Reflex
• Near Reflex is PRESENT
• Both Pupils are involved
• DILATE POORLY with MYDRIATICS
• DUE to LESION in REGION of TECTUM

Question 12

What is ADIE’s TONIC PUPIL?

Answer 12

• ABSENT Light Reflex
• SLOW Near Reflex
• Unilateral