Abstract
Purpose:
All current laser therapies are still in great need of an accurate treatment protocol. New strategies have been developed for laser treatments that minimize the chorioretinal damage , but very little attention is been given to the real fixation point at the time of the photocoagulation. The purpose of this investigation is to suggest an optimized delivery technique where in addition to the central fovea an additional area of 500 microns from the center of the new fixation point is preserved from treatment as well or treated only with micropulse laser.
Methods:
Twenty eyes of 16 patients with DME were treated using a yellow micropulse laser (577 nm) and sparing the 500 micron from the center of the fovea and the 500 microns from the center of the new fixation point as defined by fundus microperimetry. The mean retinal sensitivity within the central 10 degrees and the fixation point were measured with a fundus-related microperimeter, MP1, ETDRS-best corrected visual acuity (BCVA), optical coherence tomography-determined central macular thickness (CMT), and fluorescein angiography (FA) were performed before, 1, 3 and 6 months after a single treatment.
Results:
Central macular thickness decreased by an average of 199 μm. At 6 months main change in visual acuity was 4 letters better. Mean macular sensitivity improved (P<0.005) at 3 and 6 months. Laser lesions were not clinically observed by any means.
Conclusions:
Among the usual variables that determine the success of any laser therapy approach, the sparing of the fixation point when localized outside of the anatomical fovea has emerged as a new, important variable to consider in preventing a possible negative therapeutic effect.
Keywords: 688 retina •
578 laser •
499 diabetic retinopathy