Prediction of visual outcome after retinal detachment surgery using the Lotmar visometer

Abstract

Aim: To evaluate whether an achromatic interferometer, the Lotmar visometer, is useful in predicting postoperative visual outcome in patients with primary rhegmatogenous retinal detachment (RD) involving the macula.

Methods: This prospective study included 40 eyes of 40 non-consecutive patients with macula-off RD. The eyes were phakic or pseudophakic, had a clear optical media, and had a measurable potential vision on preoperative visometric examination. Preoperative variables included Snellen visual acuity, duration of macular detachment, extent of RD, and visometric potential acuity. Reattachment surgery consisted of radial scleral buckling in 33 patients, circumferential scleral buckling and encircling in seven patients, and subretinal fluid drainage in 10 patients. Retinal breaks were treated with cryotherapy or laser photocoagulation. Patients were followed up for at least 6 months after uncomplicated surgery. Best corrected visual acuity measured at any time during follow up was correlated with the preoperative variables.

Results: Preoperative visual acuity was less than 20/200 in 37 (93%) of 40 patients. Potential visual acuity of 20/200 or better was measured using the Lotmar visometer in 37 patients (93%). Postoperative visual acuity was correlated significantly with duration of macular detachment (r=0.55; p<0.001), and extent of RD approached statistical significance (r=0.31; p=0.05). There was a higher correlation between postoperative visual acuity and the visometric measurements (r=0.61; p<0.001).

Conclusions: The Lotmar visometer may be a valuable method to estimate visual outcome after uncomplicated scleral buckling surgery in patients with RD involving the macula.