Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What does a blue color in the GDx instrument image indicate?

1. Normal nerve fiber layer thickness

2. Thinning of the nerve fiber layer

3. Corneal irregularities

4. Increased fluid retention

The correct answer is: Thinning of the nerve fiber layer

In the context of GDx imaging, a blue color in the instrument image is indicative of thinning of the nerve fiber layer. The GDx (Glaucoma Detection) instrument evaluates the thickness of the retinal nerve fiber layer, which is crucial for assessing the health of the optic nerve and for detecting glaucomatous damage. When the nerve fiber layer is thinner than normal, it is represented by a blue color on the GDx image, signaling potential issues in the optic nerve that could lead to vision loss if not monitored or treated. The presence of a blue hue serves as a warning sign that the nerve fibers are not as robust as they should be, possibly due to diseases such as glaucoma. Interpreting GDx images correctly is essential for early detection and management of optic nerve diseases, thus making awareness of color coding and what it signifies a key component in clinical practice. Other options do not correctly relate to the color blue in the GDx imaging system.