To investigate therapeutic effect of ranibizumab on the change of sub-foveal choroidal thickness (SFCT) in eyes with macular edema secondary to central retinal vein occlusion (CRVO).

From November 2019 to October 2021, 54 patients (54 eyes) with macular edema secondary to CRVO received intravitreal injection of ranibizumab in the Eye Center of Beijing Tongren Hospital affiliated to Capital Medical University. Among them, there were 30 males (30 eyes) and 24 females (24 eyes) with the average age of (55.27±12.03) years-old (ranged from 25 to 71 years-old). All eyes were treated with intravitreal injection of ranibizumab. The treatment scheme was once a month for the first 3 months, and then injected as needed according to the patient′s condition after 3 months. All patients were followed up for 6 months. The foveal retinal thickness (CFT) and the macular foveal choroidal thickness (SFCT) of patients were recorded and measured before and after treatment. The data of CFT and SFCT conform to the normal distribution after inspection, and were expressed by ±s. The comparison of CFT, SFCT before and after treatment, SFCT between the affected eye and the contralateral eye before treatment, and SFCT between the affected eye and the contralateral eye after treatment were all performed by paired sample t test.

Before treatment, the CFT of the affected eye was (653.37±235.46)μm. After treatment for 1 month, 2 months, 3 months, 4 months, 5 months and 6 months, the CFT of the affected eyes were (342.36±136.54)μm, (265.31±94.87)μm, (253.01±181.26)μm, (313.54±102.43)μm, (251.12±98.34)μm and (226.13±70.18)μm, respectively. The CFT of the affected eyes was thinner than that before treatment, and the difference was statistically significant (t=(8.397), 11.233, 9.901, 9.725, 11.584, 12.778; P<0.05). Before treatment, the SFCT of the affected eye and the contralateral eye were (323.27±52.24)μm and (253.26±70.13)μm. The SFCT of the affected eyes after treatment for 1 month, 2 months, 3 months, 4 months, 5 months and 6 months were (261.32±80.17)μm, (243.16±65.23)μm, (249.26±59.32)μm、(251.21±72.28)μm, (263.52±63.74)μm and (256.53±72.19)μm, respectively. The SFCT of contralateral eyes were (251.34±43.26)μm, (254.27±44.16)μm, (252.64±48.27)μ m, (251.67±32.89)μm, (252.45±52.36)μm and (253.79±42.57)μm, respectively. SFCT of the affected eye after treatment for 1 month, 2 months, 3 months, 4 months, 5 months and 6 months was thinner than that before treatment, and the difference was statistically significant (t=4.758, 7.044, 6.881, 5.938, 5.328, 5.504; P<0.05). Before treatment, SFCT of the affected eye was thicker than that of the contralateral eye, and the difference was statistically significant (t=5.883, P<0.05). After treatment, there was no significant difference in SFCT between the affected eye and the contralateral eye (t=0.805, -1.036, -0.325, -0.043, 1.134, 0.240; P>0.05), which indicating that before treatment, the choroidal edema of the affected eye thickened, and after treatment, the choroidal edema of the affected eye subsided and recovered to the thickness of the contralateral eye.

There also occurred choroidal edema in patients with macular edema secondary to CRVO, and intravitreal injection of ranibizumab could reduce macular retinal edema and choroidal edema at the same time.