You ask your patient to place a red lens in front of their right eye and perform the red lens test. Your patient reports seeing two images with the red image perceived to the left of the white light. What type of deviation corresponds with this finding?

When a patient sees two images during the red lens test, with the red image appearing to the left of the white image, this indicates a specific type of deviation in eye alignment. The red lens test is designed to assess the relative positions of the eyes and the patient's binocular vision.

In this scenario, the perceived position of the red image to the left suggests that the right eye is deviating outward relative to the left eye. This outward deviation can be due to either a phoria, which is a latent condition that manifests under certain circumstances, or a tropia, which is a constant misalignment observed all the time. In this case, an exophoria or exotropia matches this finding, as both conditions imply that one eye (in this case, the right eye) is positioned further out than it should be when the eyes are trying to align for binocular vision.

Exophoria typically manifests when binocular vision is disrupted, with the eyes attempting to fixate on an object but one eye (right eye) deviating outwards. The report of seeing the red image to the left reinforces this diagnosis since the shift occurs when the right eye strays outward during the test.

In summary, the observation that the red image is perceived to the left