Abstract
Abstract: :
Purpose: To evaluate the change in pulsatile ocular blood flow (POBF) following laser therapy for proliferative diabetic retinopathy and clinically significant macular edema (CSME). The relationship of ocular blood flow and diabetic retinopathy has been studied in the past. Geyer and colleagues suggested that the POBF is initially decreased with the onset of diabetes when there is no diabetic retinopathy. Subsequently, the POBF increases with the severity of retinopathy. Recently, Krepler and colleagues found a reduction in ocular blood flow following vitrectomy for diabetic complications. It was not certain whether laser therapy had any influence on POBF. We have previously shown significant reduction of POBF at 3 months follow up after laser for proliferative diabetic retinopathy but no significant reduction after treatment for CSME. This shows results of the study at 9 month follow up. Methods: 26 eyes with proliferative diabetic retinopathy and 28 eyes with CSME receiving pan–retinal photocoagulation (PRP) and macular laser therapy respectively were included in the study. POBF was measured using Blood Flow Analyser (Dicon Diagnostics; Paradigm, USA) at baseline, one month, three months and nine months following the respective laser treatment. Statistical analysis was carried out by paired student T–test. Results: The POBF was significantly reduced at one month (p= 0.0003), three months (p=0.000006) and nine months (p=0.0001) after laser for proliferative diabetic retinopathy but there no significant change after macular laser. Conclusions: The treatment benefit of PRP in patients with proliferative diabetic retinopathy may be related to the reduction in pulsatile ocular blood flow.
Keywords: diabetic retinopathy • laser • blood supply