Abstract
Purpose: :
to evaluate foveal sensitivity in diabetic patients with moderate visual loss in comparison to healthy controls with micro perimeter 1 (MP1) in order to assess localized sensitivity deficits in the central visual field.
Methods: :
Twenty–three patients, 46 eyes (mean age: 58 +/– 14) with diabetic maculopathy and twenty five controls, 50 eyes (mean age: 50 +/– 19) were included in the study. Light sensitivity was quantified by presenting stimuli with different light intensity with simultaneous real–time monitoring of the retina (intensity: 0–27.9 dB; size: Goldmann III, wavelength: 633 nm). Eye movements were controlled by semiautomatic retinal tracking.
Results: :
There was a significant difference (p<0.0001) in macular light sensitivity in diabetic patients compared to controls (19.6 +/– 0.5 dB), both in mean difference (14.1 +/– 2.7 dB. Considering retinal main alterations retinal sensitivity was if affected with microaneurisms (14.5+/–1.7), hard exudates (15.6 +/– 2.7 dB), macular edema and hard exudates in the same eye (11 +/– 3.3 dB). Temporal parts of the macula were more affected than other parts. We had further valued manually the sensitivity of isolated region with retinal changes such as atrophy area, hard exudates and laser burns.
Conclusions: :
We found in our patients an important reduction of retinal sensitivity respect to the control group. Macular light sensitivity is particularly reduced in patients with hard exudates and macular edema. In our experience microperimetry was very useful in order to record and quantify retinal sensitivity in patients with diabetic maculopathy in which visual acuity is still normal or slightly reduced. Furthermore it is important to evaluate retinal sensibility according to retinal abnormal areas and following them up. The assessment of macular light sensitivity with automatic threshold microperimetry may help to identify patients with diabetic maculopathy and could improve the management of diabetic maculopathy.
Keywords: diabetes • retina • diabetic retinopathy