3.1.9 Assesses pupil reactions.

Direct Observation competency

1. Room lights on. No glasses worn.

2. Patient looks at spot light on the screen

What are you checking?

Pupils are equally in size - check for anisocoria

Are pupils round? - pathology, surgery

Assess direct & consensual light reflexes

Shine light in RE pupil and observe extent/speed of RE pupil constriction (direct) and extend/speed of LE pupil constriction (consensual).

Remove light and observe direct & consensual dilation.

Repeat a couple times in each eye (fatigue can occur in an abnormal eye)

If abnormalities are detected, then grade pupil direct & consensual responses as:

0 (none)

1+ (very small)

2+ (small/slow)

3+ (moderate)

4+ (large/fast)

Swinging flashlight test

Shine light in RE pupil for minimum 3 seconds at a distance of 10cm.

Quickly shine the light in the LE pupil for 2 seconds.

Alternate several times.

Relative afferent pupillary defect (RAPD) detected if one eye dilates when light is shone on it.

PERRLA

P upils

E qual,

R ound and

R espond to

L ight

A ccommodative response

RAPD (Relative Apparent Pupillary Defect)

• Pathway

• Common causes

This indicates an asymmetric lesion in the afferent visual pathway on the affected side.

Afferent pathway: Retina → optic nerve → optic chiasm → optic tract → to the pretectal nucleus

Common causes:

• Optic neuritis

• Ischaemic optic neuropathy

• Severe retinal disease