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Effect of pan-retinal laser photocoagulation on plasma VEGF, endothelin-1 and nitric oxide in PDR
Tarek Ahmed Mohamed1, Sahar El-Deek Mohamed
1Department of Ophthalmology, Assiut University Hospitals, Assiut University, Assiut, Egypt.
Aim:
To study plasma levels of vascular endothelial growth factor (VEGF), endothelin-1(ET-1) and nitric oxide (NO) in patients with proliferative diabetic retinopathy (PDR) before and after pan-retinal photocoagulation (PRP).
Methods:
Forty patients (23 females and 17 males, mean age 48.5±12.2 years) with PDR without previous PRP therapy were studied. Blood samples were obtained before and 3 months after the last PRP session. Baseline (prelaser) plasma levels of VEGF, ET-1 and NO were compared with their levels in 30 healthy age- and sex- matched controls and also with plasma levels 3 months post-PRP.
Results:
Patients with PDR had significantly raised plasma VEGF (375±89ng/L), ET-1(20±5ng/L) and NO (135±53µmol/L) when compared with healthy control group (P<0.01). After PRP, there was a significant reduction in plasma VEGF (179±66ng/L), ET-1 (11±5ng/L) and NO (91±49µmol/L) levels at 3 months' follow-up but still significantly higher than healthy controls.
Conclusion:
Patients with PDR demonstrate elevated VEGF, ET-1 and NO, which decrease after successful laser treatment.
