A patient's refraction is +2.00 DS / -3.00 DC × 180°. This is classified as:

• A Mixed astigmatism ✓
• B Compound hypermetropic astigmatism
• C Simple myopic astigmatism
• D Simple hypermetropic astigmatism

Explanation

The two principal meridians are: at 180° = +2.00 D (hyperopic) and at 90° = +2.00 + (-3.00) = -1.00 D (myopic). Since one meridian is hyperopic and the other is myopic, with focal lines on opposite sides of the retina, this is mixed astigmatism. Simple myopic astigmatism has one emmetropic and one myopic meridian. Compound types have both meridians on the same side of the retina.

Reference: Clinical Optics

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.