Real time fixation point monitoring system for photocoagulation of juxtafoveal neovascularisation.

Abstract

A new real time monitoring system has been developed to locate the fixation point during juxtafoveal laser photocoagulation. The red diode laser beam is combined coaxially with the illumination beam to image a cross in the focal plane of the slit lamp, which allows projection of a red cross onto the patient's fundus. 27 patients with juxtafoveal choroidal neovascularisation were treated by photocoagulation using this system. 13 (48%) patients whose visual acuity ranged from 20/200 to 20/40 answered that it was easier to keep the focus on the cross target image than on the aiming beam. The patient maintained stable fixation throughout the treatment. The laser treatment was completed without foveal damage near the fixation point in all patients. The real time fixation monitoring system should allow surgeons to treat juxtafoveal lesions with laser photocoagulation more safely and accurately.