Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What does the Orbscan instrument measure?

1. The curvature of the sclera

2. Corneal thickness based on curvature measurements

3. Overall eye pressure

4. Corneal transparency

The correct answer is: Corneal thickness based on curvature measurements

The Orbscan instrument is primarily designed for comprehensive corneal assessment, which includes measuring corneal thickness as well as the curvature of the cornea. It utilizes a combination of Placido disk topography and slit-scanning technology to provide detailed maps of the corneal surface. By obtaining curvature measurements, the Orbscan can accurately assess corneal thickness, which is crucial for various clinical applications such as evaluating candidates for refractive surgery, understanding keratoconus progression, and planning for corneal transplants. This focus on the relationship between curvature and thickness is what makes the second choice the correct answer in this context. While the remaining options address various aspects of eye measurements, they do not accurately capture the primary function of the Orbscan. The instrument does not specifically measure scleral curvature, overall eye pressure, or corneal transparency, which are handled by other diagnostic tools or methods in the field of ophthalmology.