Abstract
Purpose: :
To evaluate visual acuity (VA) and central macular thickness changes in a series of patients with diabetic retinopathy treated with short-duration photocoagulation (SDPC) versus those treated with normal-duration photocoagulation (NDPC).
Methods: :
Prospectively, 20 eyes of 10 patients with pre-proliferative or proliferative diabetic retinopathy who had not been previously treated were treated with pan-retinal photocoagulation (PC). This study was approved by the Institutional Review Board (IRB), and previous written informed consent was obtained from all subjects. Multi-color PC was used for the pan-retinal PC, and the common PC setting (yellow color, 450-µm diameter, 300 shots per day, every 2 weeks, 4 times) was used for both groups. The right eye of each patient was treated with SDPC (0.05 seconds, 350 mW) and the left eye was treated with NDPC (0.2 seconds, 200 mW). Macular thickness obtained by optical coherence tomography (OCT) and VA were measured at the time of each procedure and at each subsequent follow-up.
Results: :
Mean patients age was 63 (range 51-78). Disease etiology was pre-proliferative diabetic retinopathy in 14 cases (70%) and proliferative diabetic retinopathy in 6 cases (30%). Mean follow up periods was 23 weeks (range 10-40). Pre and post macular thickness for the SDPC group were 216 ± 28.5 µm and 239 ± 155 µm (p = 0.63), respectively. Pre and post macular thickness for the NDPC group were 211 ± 27.3 µm and 285 ± 127 µm (p = 0.12), respectively. Comparison of the SDPC mean macular thickness change vs NDPC was statistically significant (p ≤ 0.05). Pre and post logMAR VA for the SDPC group were 0.13 ± 0.26 and 0.16 ± 0.23 (p = 0.41), respectively. Pre and post logMAR VA for the NDPC group were 0.04 ± 0.15 and 0.15 ± 0.13 (p ≤ 0.05), respectively. All patients experienced less pain with SDPC than with NDPC.
Conclusions: :
The use of SDPC results in a significantly lower incidence of macular edema and VA decrease than traditional PC. Pan-retinal PC using SDPC has few side-effects, such as macular edema, visual dysfunction, and pain.
Keywords: laser • edema • diabetic retinopathy