Automatic refraction and the private ophthalmologist: Dioptron II compared with subjective examination

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• Automated refractors are increasingly used in clinical practice.
• Evaluating the accuracy of automated refraction compared to traditional methods is crucial for patient care.

Purpose of the Study:

• To compare the accuracy of the Dioptron II refractor with manifest and cycloplegic retinoscopy and subjective refraction.
• To assess the Dioptron II's performance across different refractive components (sphere, cylinder, axis) and patient demographics.

Main Methods:

• 84 office patients underwent manifest and cycloplegic retinoscopy and subjective refraction.
• An ophthalmic assistant used the Dioptron II refractor for examination.
• Results from the Dioptron II were statistically compared to manual refraction outcomes.

Main Results:

• Agreement with manual refraction was 46% for spheres, 51% for cylinders, and 44% for spherical equivalents without cycloplegia.
• Agreement slightly increased after cycloplegia for spheres (47%), cylinders (51%), and spherical equivalents (51%).
• Axis agreement was 46% without and 29% with cycloplegia; accuracy was highest for spheres, lowest for cylinder power.

Conclusions:

• The Dioptron II refractor provides a useful starting point for refraction, with better accuracy without cycloplegia for most patients.
• Its accuracy is limited for specific patient groups, including young children, the elderly, psychiatric patients, and non-English speakers.
• The device demonstrates variable accuracy across refractive components, being most reliable for sphere power.