What procedure must be completed prior to pupillary dilation?

Prior to pupillary dilation, it is essential to perform the swinging-light test, which is used to assess the afferent pupillary defect (APD). This test helps determine whether there is any asymmetry in the pupillary response, which can indicate underlying neurological issues or ocular pathologies. By establishing a baseline of pupillary function through the swinging-light test, the clinician can better interpret changes in pupillary response after dilation.

Conducting the swinging-light test before dilation is critical because dilation alters the natural response of the pupil and can mask defects that might be present. Identifying any afferent pupillary defects beforehand ensures a more accurate assessment post-dilation, allowing for proper diagnosis and management of potential eye conditions.

While visual acuity tests, fundoscopy, and refraction tests are all important components of a comprehensive eye examination, they do not specifically address the critical needs for pupil assessment that the swinging-light test provides.