Certified Ophthalmic Medical Technologist (COMT) Practice Exam 2025 – Comprehensive All-in-One Guide to Success

A patient response to a non-projected stimulus is known as a false positive response. In the context of visual field testing, a false positive occurs when a patient indicates seeing a stimulus that was not actually presented. This can happen if the patient is overly attentive or guesses in the absence of a true stimulus, leading to an incorrect affirmation of perception. This concept is essential in understanding the reliability of visual field tests, as accumulating false positives may distort the perception of a patient's visual capabilities, suggesting an apparent field loss where none exists.

In contrast, fixation loss pertains to instances where a stimulus is actually presented, but the patient fails to respond appropriately during the test, breaking the fixation point. A false negative response refers to a situation where a stimulus is presented but the patient does not see it when they should have, indicating potential issues with detection or understanding of the testing process. A visual field defect is a broader term indicating actual loss of vision in certain areas of the visual field, which may be identified through clinical examination or visual field mapping, rather than being a response to a non-existent stimulus.