Abstract
Abstract: :
Purpose: To evaluate the effectiveness of a novel selective retinal pigment epithelium (RPE) Nd: YLF (Yttrium Lithium Flouride) laser for the treatment in diabetic maculopathy. Improvement or stabilization of visual acuity and reduction of retinal exudation on fluorescein angiography was assessed. Method: A non–comparative, clinical prospective pilot study. 20 eyes with focal or patchy diffuse oedema secondary to diabetic maculopathy. Patients with previous ocular treatment were excluded from the study. The novel Nd: YLF laser used for this study works with a wavelength of 527 nanometers and pulse duration of 2 microseconds. All patients had visual acuity (log mar) assessment, fundus photography, fluorescein angiograpy, and OCT at the pre–treatment, 3 month, and 6 month visits. Exposition of laser spots with different pulse energy (starting at 100uJ) was applied outside the macula area. Any visible laser test spots were recorded. To determine the pulse energy required for treatment, a fluorescein angiogram was performed 1 to 2 hours following the laser test spots. Selective RPE treatment was then carried out using the appropriate energy. Adverse events were recorded. Results: 11 eyes have had their 3 month visit at present. Fluorescein angiographic evidence of leakage revealed an improvement or no change in all 11 cases. Visual acuity improved by 4 letters or more in 6 eyes (55%). Vision worsened by at least 4 letters in 1 patient. At 3 months, 4 eyes had stable visual acuity (change of 3 letters or less on log mar chart) compared with pre–treatment. None of the patients reported any adverse effects from the laser treatment. Conclusion: The beneficial effect of laser treatment in diabetic macular oedema is thought to be associated with the restoration of the RPE. Based on this concept, selective RPE photocoagulation techniques have been developed to spare the photoreceptors and therefore reduce unnecessary side effects. This pilot study shows promising results with the novel Nd: YLF laser. Flourescein angiogram showed a reduction of leakage in all patients followed up at 3 months. 91% of patients, examined so far, had an improvement or stabilization in visual acuity at 3 month follow up.
Keywords: diabetic retinopathy • retinal pigment epithelium • laser