Pupils Flashcards
What is pupil assessment?
A crucial part of an eye exam and neurological evaluation that helps determine the integrity of the afferent and efferent pathways of the visual system.
List the key aspects to assess during pupil evaluation.
- Pupil Size and Shape
- Pupil Equality
- Direct and Consensual Light Reflex
- Swinging Flashlight Test (RAPD)
- Near Response (Accommodation Reflex)
What is the normal size range for pupils in bright light?
2-4 mm
What is the normal size range for pupils in dim light?
4-8 mm
What does it indicate if pupils are unequal in size?
Anisocoria
What is considered anisocoria?
A difference in pupil size greater than 1 mm
What does anisocoria greater in bright light suggest?
A parasympathetic defect (e.g., third nerve palsy, Adie’s tonic pupil)
What does anisocoria greater in dim light suggest?
A sympathetic defect (e.g., Horner’s syndrome)
What does the Direct and Consensual Light Reflex test?
The afferent (optic nerve - CN II) and efferent (oculomotor nerve - CN III) pathways
What is the procedure for the Direct and Consensual Light Reflex test?
- Darken the room
- Instruct patient to fixate on a distant object
- Shine a penlight into one eye and observe direct and consensual responses
What indicates an issue in the efferent pathway during the Direct and Consensual Light Reflex test?
No constriction in direct response
What is the Swinging Flashlight Test used to detect?
Asymmetry in the afferent pathway
What is a normal response in the Swinging Flashlight Test?
Both pupils constrict equally regardless of which eye is illuminated
What does RAPD stand for?
Relative Afferent Pupillary Defect
What happens to the pupils in the presence of RAPD?
Both pupils paradoxically dilate instead of constricting when light is swung to the affected eye
What does the Near Response test?
The triad of accommodation, convergence, and miosis
Describe the procedure for testing Near Response.
- Ask the patient to look at a distant object
- Shift focus to a near target (~15 cm from the nose)
- Observe pupil constriction as the eyes converge
What is the normal response during the Near Response test?
Pupils constrict when focusing on the near target
What is Light-Near Dissociation?
Pupils constrict with accommodation but not with light
What condition is associated with Argyll Robertson pupil?
Neurosyphilis
What characterizes Horner’s Syndrome?
- Miosis (small pupil)
- Ptosis (droopy eyelid)
- Anhidrosis (lack of sweating)
What indicates Third Nerve Palsy?
- Dilated pupil poorly reactive to light
- May have ptosis
- Eye positioned ‘down and out’
What is characteristic of Adie’s Tonic Pupil?
- Dilated pupil with sluggish reaction to light
- Better near response
- Often unilateral
What is the Argyll Robertson Pupil?
Small, irregular pupils that constrict with accommodation but not to light
What does RAPD indicate?
Afferent pathway defect (e.g., optic nerve damage)
