To evaluate the reproducibility and repeatibility of biometry in cataractous eyes, pseudophakic eyes and eyes having undergone refractive surgery. The OcuScan®RxP, LENSTAR® and IOL Master® instruments were compared, as were. The accuracies of the refractive results after cataract surgery.

The biometries of 45 cataractous eyes, 31 pseudophakic eyes, and 32 eyes having undergone refractive surgery were measured by two practitioners using OcuScan®RxP, LENSTAR® and IOL Master® instruments. The paired t -test was used to compare the reproducibilities in the three groups.

There were no differences in axial length among the groups when using any of the instruments. There was no significant difference in the repeatibility regardless of the instrument used, although. In the cataractous eyes, pseudophakic eyes and eyes with refractive surgery, OcuScan®RxP showed the highest repeatability. However, we knew that all three instruments were excellent in the repeatability because the difference was less than 1.5%. The Prediction error of the instruments with regard to refractive results could not be determined after cataract surgery. In some patients with severe cataract, measurement was impossible for both the LENSTAR® and IOL Master® instruments.

In all groups, OcuScan®RxP, LENSTAR® and IOL Master® showed no significant differences with regard to reproducibility or prediction of refractive power after surgery. Among three groups, the repeatability was rather high in the existing ultrasound method than in the partial coherence interferometers. In some patients with severe cataract, measurement was impossible for both the LENSTAR® and IOL Master® instruments.