Prediction of visual acuity loss and indications for laser treatment in patients with diabetic macular edema using the Heidelberg Retina Tomograph.

摘要

Aims. To correlate loss of vision due to macular edema with the Heidelberg Retina Tomograph (HRT) and to quantify volumetric measurements with regards to the need for laser treatment.;Methods. A retrospective study was conducted on 168 eyes, 115 eyes from 80 diabetics and 53 eyes from 45 non-diabetic patients were used that underwent HRT macular assessment. Patients with diabetic retinopathy who were found to have macular edema, underwent volumetric measurements by the HRT Macular Edema Module (MEM), and referred to a retina specialist for consultation for possible treatment options. Comparison of volumetric measurements to visual acuity and the need for treatment, as well as type of treatment (focal laser, grid laser, or no treatment except observation) was assessed for correlation. Comparison of diabetic MEM to the normal (non-diabetic) was also assessed.;Results. Bivariate analysis of LogMAR visual acuity and mean edema index as measured by the HRT macular edema module demonstrated a linear fit between the two parameters. The mean edema index of diabetics that did not require laser treatment was 1.19 edema index units, while the treatment group had a mean index of 1.92 index units. Type of treatment (none, focal, or modified grid laser) was statistically significant. A mean index of 1.18 or less required no treatment; a mean index of 1.82 required focal laser, while a mean macular index of 2.13 required a modified grid laser treatment.;Conclusions. Mean macular edema index may be used to: (a) estimate loss of visual acuity; (b) categorize amount of macular edema; and (c) estimate what type of treatment (none, focal- and grid-laser) that might be needed. The HRT MEM is a useful adjunctive tool in the detection and treatment of diabetic macular edema. Large, multi-site prospective studies are needed to fully assess the clinical usefulness of the HRT MEM.