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Updated: Aug 4, 2026

Using an Automated Hirschberg Test App to Evaluate Ocular Alignment
Published on: March 24, 2020
Phakometric measurement of ocular surface radius of curvature and alignment: evaluation of method with physical model
J C Barry1, M Dunne, T Kirschkamp
1University Eye Clinic Department II, Medical Faculty, Eberhard-Karls-Universität Tübingen, Germany.
Abstract:
Ophthalmophakometric measurements of ocular surface radius of curvature and alignment were evaluated on physical model eyes encompassing a wide range of human ocular dimensions. The results indicated that defocus errors arising from imperfections in the ophthalmophakometer camera telecentricity and light source collimation were smaller than experimental errors. Reasonable estimates emerged for anterior lens surface radius of curvature (accuracy: 0.02-0.10 mm; precision 0.05-0.09 mm), posterior lens surface radius of curvature (accuracy: 0.10-0.55 mm; precision 0.06-0.20 mm), eye rotation (accuracy: 0.00-0.32 degrees; precision 0.06-0.25 degrees), lens tilt (accuracy: 0.00-0.33 degrees; precision 0.05-0.98 degrees) and lens decentration (accuracy: 0.00-0.07 mm; precision 0.00-0.07 mm).

