AIM: To study the influence of intravitreal injection of bevacizumab combined with photon dynamic treatment(PDT)in the treatment of central serous choroiretinopathy(CSC).

METHODS:We selected 82 CSC patients treated in the hospital between February 2012 and April 2015, who were diagnosed by optical coherence tomography(OCT)and fundus fluorescein angiography(FFA)and all got the disease monocularly, and divided them into two groups called control group(n=35)and research group(n=47)by different methods, the patients of control group were treated by PDT method, while the patients of research group were treated by vitreous bevacizumab injection combined with PDT. Then compare the number of treatment times, the rate of flat pigment epithelial detachment(PED), macular subretinal fluid absorption, OCT indexes such as volume of the macular central hub, average thickness of central macular with diameter of 6mm and thickness of central macular region below 1mm range, the difference of corrected vision and clinical efficacy of two groups before and after the treatment.

RESULTS: There were 32 eyes which were treated once, and 3 eyes which were treated twice in the control group, the average treatment times was 1.25±0.20; however, there were 9 eyes which were treated three times, 10 eyes twice, 28 eyes once, the average treatment number was 1.48±0.22, the treatment times of two groups had no statistical difference(t=1.209, P>0.05). On the other hand, 13 eyes' PED(37%)was flat in the control group, 22 eyes(63%)which macular retinal subepithelial serous absorption; 30 eyes' PED(64%)was flat in the research group, 17 eyes(36%)which macular retinal subepithelial serous absorption. The rate of flat PED and macular retinal subepithelial serous absorption of two groups had obvious statistical difference(P<0.05). The OCT indexes such as volume of the macular central hub, average thickness of central macular with diameter of 6mm and thickness of central macular region bellow 1mm of two groups had no statistical difference before the treatment(P>0.05), in contrast these OCT indexes were all much lower than control group after the treatment, and the results had obvious statistical difference(P<0.05). Besides, these OCT indexes after treatment were all much lower than that of two groups before treatment respectively, and it also had obvious statistical difference(P<0.05). After 1-month's treatment, the LogMAR corrected vision of two groups had no statistical difference(P>0.05). While the LogMAR corrected vision of research groups had statistical difference with control group after 3mo and 6mo(P<0.05). There were 6 invalid cases, 15 improvement cases, 8 excellence cases and 6 healing cases in the control group; the total effective rate of control group was 83%. While there were 3 invalid cases, 8 improvement cases, 20 excellence cases, 16 healing cases in the research group, the total effective rate of research group was 94%. The effective rate of two groups had obvious statistical difference(P<0.05).

CONCLUSION: In the treatment of chronic CSC with PED patients, the method of vitreous bevacizumab injection combined with low dose PDT has better effect on PED flat, promoting macular subretinal serous absorption, reducing macular thickness and improving visual acuity.