Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What type of test is utilized to assess the reliability of the rods in patients with night vision difficulties?

1. Contrast sensitivity test

2. Dark adaptometry

3. Color vision test

4. Standard visual acuity test

The correct answer is: Dark adaptometry

The use of dark adaptometry is specifically designed for evaluating the functionality of the rods in the retina, which are crucial for vision in low-light conditions. This test measures how well a person's eyes can adjust from a well-lit environment to a dark one, thereby assessing the speed and efficiency of dark adaptation. This adaptation process largely involves the rods, which respond to dim light and generally become more sensitive as the eyes transition to darkness. In contrast sensitivity tests focus on the ability to distinguish between shades of gray under varying light conditions but do not specifically target rod functionality. Color vision tests assess the ability to perceive different wavelengths of light, primarily evaluating cone function, and standard visual acuity tests measure clarity of vision but are not indicative of night vision capabilities. Therefore, dark adaptometry is the most appropriate choice for assessing night vision difficulties related to rod reliability.