Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What type of astigmatism is indicated by spectacle powers of +2.00 +2.00 x 180?

1. Simple myopic astigmatism

2. Compound hyperopic astigmatism

3. Irregular astigmatism

4. Mixed astigmatism

The correct answer is: Compound hyperopic astigmatism

The spectacle powers presented, +2.00 +2.00 x 180, indicate that the individual has a compound hyperopic astigmatism. This specific type of astigmatism occurs when a person has two positive refractive powers, meaning both principal meridians are hyperopic. In this case, there are two spherical powers of +2.00, which leads to hyperopia in both the vertical and horizontal meridians. The orientation of the astigmatism, denoted by the 'x 180', indicates that the second principal meridian is at 180 degrees. Since the powers are equal and positive, this reinforces that the astigmatism is compound and hyperopic, rather than simple, irregular, or mixed. Understanding the terms used is crucial: "simple" would imply that one meridian is emmetropic (normal vision) while the other is not, which is not the case here; "irregular" refers to non-standard corneal shapes affecting vision more variably; and "mixed" would involve one meridian being myopic (nearsighted) and the other hyperopic, which does not apply in this situation. Thus, compound hyperopic astigmatism accurately describes