You are performing the red-glass test in an adult patient with exotropia prior to undertaking bilateral lateral rectus recessions. The patient states that he sees a "pinkish" single light when you shine the test light at him. Which of the following best describes this situation?
Amblyopia / Strabismus
The red-glass test is one of several methods to test for the presence of anomalous retinal correspondence (ARC). The test begins with measuring the patient's deviation objectively with prism. A red glass is then placed over the non-deviating eye while the patient fixates on a white light. The patient is asked what he sees. If the patient only sees one light, then suppression is present. If the patient sees the lights superimposed on each other (i.e. pink) despite a measurable deviation, then harmonious ARC is present. If the patient sees 2 lights but the separation between the lights is smaller than the measured deviation, then unharmonious ARC is present.