Certified Ophthalmic Medical Technologist (COMT) Practice Exam

The response of a patient to a stimulus projected into a previously located blind spot is properly categorized as fixation loss. In visual field testing, a blind spot is an area of the visual field where the patient has no vision due to the absence of photoreceptors in that part of the retina, typically around the optic nerve head. If a patient registers seeing a light stimulus in this blind spot area, it indicates that they have lost the proper fixation during the test procedure. This response demonstrates that the patient might be unintentionally shifting their gaze or failing to maintain accurate and consistent fixation, which can affect the validity of the test results. Hence, fixation loss captures this phenomenon best in the context of visual field assessment. Other options represent different concepts within visual field testing, where false negative responses suggest that a patient does not respond to a stimulus when it is known they should see it, false positive responses indicate a perception of a stimulus where none exists, and visual field artifacts refer to distortions or inaccuracies in the visual field measurements often due to extraneous factors. However, none of these terms accurately describe the specific situation of a response in the blind spot as fixation loss does.