Certified Ophthalmic Medical Technologist (COMT) Practice Exam

The test that assesses central visual distortion and loss with horizontal and vertical lines is known as what?

1. Amsler grid

2. Snellen chart

3. Berkeley rudimentary grid

4. Visual field map

The correct answer is: Amsler grid

The Amsler grid is specifically designed to detect issues related to central vision, particularly problems such as distortion and loss of straight lines. This grid consists of a series of horizontal and vertical lines, creating a checkerboard pattern, which helps in evaluating the macula's functionality. When individuals look at the center of the grid, they are asked to report any alterations they notice with the lines—such as bending, blurring, or missing lines. Such distortions can be indicative of various macular conditions, including age-related macular degeneration or other retinal disorders, making the Amsler grid a valuable tool in clinical settings for early detection of vision problems. In contrast, the Snellen chart is primarily designed for measuring visual acuity rather than assessing distortion or loss in visual fields. The Berkeley rudimentary grid is less commonly referenced in clinical practice and may serve different purposes. The visual field map assesses peripheral vision, not central distortions specifically. Thus, the Amsler grid is the most appropriate and effective tool for assessing central visual distortion and loss in this context.