Abstract
Purpose: :
To determine the reproducibility of measurements of point spread function with an OQAS (Optical Quality Analysis System, Visiometrics S.L, Spain) instrument.
Methods: :
One hundred eyes of 100 patients were included in this prospective study. Fifty eyes of 50 patients scheduled for cataract surgery and fifty eyes of 50 consecutive patients, listed for Nd:YAG laser capsulotomy due to posterior capsule opacification (PCO) were measured with OQAS three times after pupil dilation. Patients were asked to lean back after each measurement. Main outcome was the intra-observer reproducibility using the optical scatter index (OSI). Additional outcome was the number of patients that was not measured successfully.
Results: :
There was high intra-examiner reproducibility for OSI values in patients with cataracts and in patients, scheduled for Nd:YAG capsulotomy. Less than ten percent of patients could not be measured in each group. In all cases this was due to dense opacities (cataract, or PCO).
Conclusions: :
The OQAS showed good intra-observer reproducibility. Measurements were easy to perform in all patients with mild to moderate cataract and PCO.
Keywords: optical properties • aberrations