Pattern scan laser versus single spot laser in panretinal photocoagulation treatment for proliferative diabetic retinopathy

AIM: To investigate the efficacy of 577-nm pattern scan laser in panretinal photocoagulation(PRP)treatment in newly diagnosed proliferative diabetic retinopathy(PDR).<p>METHODS:Prospective and comparative observation was performed in totally 32 patients with high-risk PDR. They were randomly divided into group 1(using pattern scan laser, PSL)and 2(using single spot laser, SSL), each containing 16 subjects to which totally 20 eyes received PRP. Non-perfusion region was identified with fundus fluorescein angiography(FFA)before and 3mo after final PRP. The advantage of PSL was verified in terms of the number and the duration of PRP sessions needed for satisfactory outcomes, and the pain score.<p>RESULTS: Three PRP sessions were needed for each eye to complete the treatment using PSL, while 4 sessions were needed using SSL. The duration of each session with PSL in group 1 was 7.3±2.3min, which was significantly shorter than that with SSL in group 2(13.2±4.1, <i>t₃₈</i>=5.596, <i>P</i><0.001). Treatment-related pain score was also significantly lower in group 1 than in group 2(<i>P</i><0.01). Three months after the final PRP, the number of eyes with retinal non-perfusion regions that required additional treatment was 5(25%)in group 1 and 8(40%)in group 2.<p>CONCLUSION: PSL showed clear advantages over SSL in the PRP treatment of PDR, not only in the improved efficacy, but also in the reduction of pain and the improvement of effectiveness