Abstract
To determine whether patient-customized paraxial eye models that do not rely on exact ray-tracing and do not consider aberrations can accurately predict pseudophakic refraction.
Bascom Palmer Eye Institute, Miami, FL, USA.
Prospective study.
Cataract surgery patients with and without a history of refractive surgery were included. Manifest refraction, corneal biometry, and extended-depth OCT imaging were performed at least one month after surgery. Corneal and OCT biometry were used to create paraxial eye models. The pseudophakic refraction simulated using the eye model was compared to measured refraction to calculate prediction error.
In total, 49 eyes of 33 subjects were analyzed, of which 12 eyes from 9 patients had prior refractive surgery. In eyes without a history of refractive surgery, the average prediction error was 0.08 ± 0.33 D ranging from -0.56 to 0.79 D with a mean absolute error of 0.27 ± 0.21 D. 31 eyes were within ± 0.5 D, and 36 eyes were within ± 0.75D. In eyes with prior refractive surgery, the average prediction error was -0.44 ± 0.58 D ranging from -1.42 to 0.32 D, and the mean absolute error was 0.56 ± 0.46 D. 7 out of 12 eyes were within ±0.5 D, 8 within ±0.75 D, and 10 within ± 1 D. All eyes were within ± 1.5 D.
Accurate calculation of refraction in post-cataract surgery patients can be performed using paraxial optics. Measurement uncertainties in ocular biometry are a primary source of residual prediction error.
