Scanning laser ophthalmoscope fundus perimetry before and after laser photocoagulation for clinically significant diabetic macular edema

PURPOSE: To prospectively evaluate functional and funduscopic changes after laser treatment in patients with diabetic retinopathy and clinically significant macular edema by scanning laser ophthalmoscope fundus perimetry. METHODS: Thirty eyes of 30 patients with clinically significant macular edema as a result of diabetic retinopathy were prospectively examined before and at least 3 months after focal laser treatment with automatic fundus threshold perimetry using the scanning laser ophthalmoscope. Thresholds of light sensitivity were compared with age-corrected normal values and correlated with corrected visual acuity and subjective appraisal of visual function. RESULTS: In 30 eyes, fundus perimetry lasted for 10.5 ± 2.7 (mean ± SD) minutes with 322 ± 67 stimulus presentations for each eye. Whereas eight eyes remained stable (< ±1 dB change), 15 improved concerning mean deviation (MD) (3.1 ± 1.7 dB) after focal laser treatment. Stability of fixation remained the same after focal laser treatment (0.75 ± 0.57 degree). Laser scars showed marked loss of function (MD > 13 dB). CONCLUSIONS: Although light sensitivity was reduced in areas of macular edema, there was no correlation between the amount of edema and visual function. Fundus perimetry allows the creation of exact maps of retinal dysfunction before and after laser treatment. It may help in making management decisions in diabetic and nondiabetic patients by offering a sensitive parameter in addition to visual acuity.