ICGA Combined With OCT To Evaluate The Changes Of Choroidal Thickness And Fluorescence In Lesions Before And After Laser And Photodynamic Therapy For CSC

Objective: ICGA combined with OCT to evaluate the changes of choroidal thickness and fluorescence in lesions before and after laser photocoagulation and half-dose photodynamic therapy for central serous choroidal retinopathy.Methods: The research included 60 patients(60eyes)diagnosed as central serous chorioretinopathy by optical coherence tomography(OCT),fundus fluorescein angiography(FFA),and indocyanine green angiography(ICGA).According to the course of the disease and the positional relationship between the leakage point on the FFA and the center of the macula,it was divided into two groups,Half-dose photodynamic therapy(PDT)treatment group,Leakage points within 500 um of the macula fovea or patients with a chronic course.Laser treatment(LP)group,the leakage point is 500 um away from the macula fovea,and the disease duration was less than 6 months.30 patients(30 eyes)in each group.The PDT group was treated with 1/2 dose of verteporfin,and the LP group was treated with ordinary yellow laser.The best-corrected visual acuity(BCVA)and frequency-domain OCT was reviewed at1 month after treatment,and the BCVA examination used international standard vision chart and converted to log MAR vision record.The best-corrected visual acuity(BCVA),frequency-domain OCT,FFA,and ICGA were reviewed at 3 months after treatment.The mean choroidal thickness of the lesion area was measured by EDI-OCT combined with ICGA measurements.The choroidal thickness of the lesion center and the center of the lesion to five points at the midpoint of the upper,lower,nasal,and temporal edges of the lesion were measured.Finally,the average was calculated.The change in the gray fluorescence ratio in ICGA was recorded by the fluorescence gray ratio results of the area processed by PDT and unprocessed.BCVA and subretinal fluid(SRF)were secondary observation indicators.Results:(1)Comparison of logMAR BCVA before and after treatment between the two groups.The BCVA(log MAR)in the LP group was 0.31±0.26,0.06±0.07,0.04±0.09 at baseline,1 month after treatment,and 3 months after treatment,respectively.The difference was statistically significant(F=36.267,P < 0.001,and F=25.26,P < 0.001),there was no significant difference between 3 months after treatment and 1 month after treatment(F=0.906,P=0.345).The BCVA(log MAR)in the PDT group was 0.31±0.21,0.11±0.15,0.05±0.15 at baseline,1 month,and3 months after treatment,respectively.The difference was statistically significant(F=37.084,P<0.001,and F=19.08,P<0.001).There was no significant difference between 3 months after treatment and 1 month after treatment(F=2.953,P=0.091).(2)Absorption of subretinal fluid in two groups.1 month after treatment,The subretinal fluid of 28 eyes(93.3%)in the PDT group were utterly absorbed.22 eyes(73.3%)in the LP group were wholly absorbed,The difference was statistically significant(χ2=4.32,P=0.038).3 eyes recurred(90%)at 3 months after treatment in LP group,otherwise,all eyes were cured in PDT group,The difference was not statistically significant(χ2=1.404,P=0.236).(3)The changes of mean choroidal thickness before treatment and 3 months after treatment in each group and 3 months after treatment in both groups: Mean choroidal thickness in the PDT group was 420.47±25.47,337.33±21.67 at baseline,3months after treatment,respectively.The difference was statistically significant(F=786.823,P < 0.001).Mean choroidal thickness in the LP group was 416.90±29.31,399.67±28.89 at baseline,3months after treatment,respectively.Their difference was statistically significant(F=112.288,P<0.001).The difference between the PDT group and the LP group was statistically significant at 3months after treatment(t=9.454,P<0.001).(4)The changes in the ratio of fluorescence in Indocyanine Green Angiography before treatment and 3 months after treatment in each group and 3 months after treatment in both groups: The mean gray value ratio of fluorescence in the PDT group was 1.29±0.09,1.05±0.2 at baseline,3months after treatment,respectively,the difference was statistically significant(t=7.189,P<0.001).The mean gray value ratio of fluorescence in the LP group was 1.33±0.09,1.18±0.13 at baseline,3months after treatment,respectively.Their difference was statistically significant(t=7.536,P<0.001).The difference between the PDT group and the LP group was statistically significant at 3 months after treatment(t=2.761,P<0.001).(5)There was a significant positive correlation between the mean thickness of choroid and the mean gray ratio in the LP group(r=0.383,P=0.037)。Conclusion:(1)Both PDT and LP treatments can help improve the vision of CSC patients,PDT can promote the absorption of subretinal fluid more rapidly than LP.(2)PDT and LP decrease the mean choroidal thickness in the high perfusion area,and PDT is more evident than LP.(3)The decrease in the mean fluorescence ratio of choroidal lesions in the PDT group is more significant than that in the LP group;in other words,PDT improves the degree of choroidal hyperperfusion better.