The pupillary light reflex is not reliably present until approximately 30 weeks’ gestational age. Pupils are usually miotic in newborns and gradually increase in size until preadolescence. Accurate pupil testing in young children is complicated by the smaller pupil and difficulty controlling accommodation. Careful observation, remote or foot control of the room lights to allow continued observation during changes in room illumination, and use of appropriate distance fixation targets greatly facilitate pupil evaluation. Digital photography can also be useful for observing and documenting pupil size and symmetry.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.