Retinal circulation times in patients with diabetes mellitus before and after lasercoagulation

Patients and methods By means of videofluoresceinangiography arm-retina-time (ART) and retinal arteriovenous passage time (AVP) were measured in order to determine the effect of panretinal lasercoagulation on retinal circulation in patients with diabetic retinopathy. 55 patients with either pre-proliferative (n = 29) or proliferative (n = 26) retinopathy were examined before, 3-9 weeks after panretinal lasercoagulation (mean: 848 burns, 0.5 mm diameter), and 0.5-3 years later. Results The ART of the diabetic patients was in the normal range and showed no differences among the three measuring times. The retinal AVP was significantly prolonged in the three measuring times (nasal and temporal) when compared to normals. Lasercoagulation showed no significant effect on AVP in the temporal branches, whereas in the nasal branches AVP decreased from 2.38 +/- 0,69 s (before lasercoagulation) to 2.11 +/- 0.68 s (3-9 weeks after treatment) and 2.06 +/- 0.67 s (0.5-3 years after treatment) (p < 0.01). In branches with neovascularisation (n = 24) a pronounced decrease of AVP from 2.60 +/- 0.70 s to 1.96 +/- 0.61 s and 2.09 +/- 0.64 s (p < 0.01) was detected. Conclusions Thus? lasercoagulation leads to a faster circulation in areas with laser burns within 3-9 weeks post-treatment.