PERRLA is an acronym used to describe normal pupillary findings: Pupils Equal, Round, Reactive to Light and Accommodation. It is a quick neurological screening element of an eye exam.
How it is assessed
The examiner looks at shape, size, and responses.
- Checking that both pupils are the same size and round
- Shining a light to observe direct and consensual constriction
- Asking the patient to shift focus from distance to near to check accommodation
- Noting any anisocoria, sluggish reaction, or light-near dissociation
Clinical significance
Abnormalities may signal serious disease.
- Helps detect afferent defects, third nerve palsy, Horner syndrome, or pharmacologic dilation
- Important in head injury, stroke, and raised intracranial pressure assessment
- Often recorded alongside visual acuity and eye movements in routine exams
- Further neuro-ophthalmic testing is arranged if responses are abnormal
