Refractive Errors of Vision

Check eye power (in diopters) and visual acuity by Snellen chart.

Clinical Features

Frontal headache (particularly with hypermetropia and astigmatism) discomfort and blurring of vision after near work, burning and dryness of eyes and defective vision.

Likely cause and Management

• Use pinhole test, if it is positive, it can be corrected by lenses (wearing spectacles) otherwise not.
• Myopia is corrected by concave lenses (-ive sign).
• Hypermetropia is corrected by convex lenses (-ive sign).
• Presbyopia is corrected by concave + convex lenses.