Clinical comparison of the SITE IRAS hand-held interferometer and Haag-Streit Lotmar visometer

The preoperative testing of retinal acuity was evaluated using two instruments in each of 35 eyes having extracapsular cataract extraction. Retinal acuity was measured using the SITE IRAS hand-held interferometer and the Haag-Streit Lotmar visometer. The postoperative findings are given for comparisons of final acuity, prediction, and instrument evaluation. The results showed predicted acuity to be within two lines of the final acuity in 57.1% of eyes with the Haag-Streit unit and in 42.8% of eyes with the SITE instrument. The instrument differences were more in procedure than in results.