Correlation between disorganization of retinal inner layers and visual prognosis after vitrectomy in proliferative diabetic retinopathy patients / 中华眼底病杂志

ABSTRACT

Objective:To analyze the correlation between disorganization of retinal inner layers (DRIL) and visual prognosis after pars plana vitrectomy (PPV) in patients with proliferative diabetic retinopathy (PDR).Methods:A retrospective observational systematic cases study. From January 2019 to January 2020, 52 patients (58 eyes) with PDR who were treated with PPV in the department of ophthalmology of The First Affiliated Hospital of Anhui University of Science & Technology were included in the study. There were 24 males (29 eyes) and 28 females (29 eyes), aged from 45 to 80 years old, with the mean age of 62.95 ±9.38 years. All patients were examined BCVA by using international standard visual acuity chart, and the results were converted into logMAR visual acuity in stastistics. The mean preoperative logMAR BCVA was 2.51±0.69. All patients underwent 23G standard PPV by the same physician. Spectral domain-OCT (SD-OCT) was performed to measure DRIL length within 1 mm of macular area diameter, ellipsoid zone (EZ) fracture length and foveal retinal thickness (CMT) one month after operation. According to the length of DRIL, the patients were divided into three groups non-DRIL group, DRIL≤500 μm group and DRIL> 500 μm group. The differences of BCVA and the SD-OCT parameters were compared among the three groups after PPV. The postoperative BCVA of the three groups were compared by Kruskal-Wallis H test, and the pairwise comparison between the three groups were performed by Bonferroni correction method. Wilcoxon rank sum test was used to compare BCVA in each group at 1 and 6 months after operation. Spearman rank correlation analysis was used to analyze the correlation between BCVA and measurement parameters of SD-OCT at 1, 3 and 6 months after operation. Multivariate stepwise regression analysis was used to analyze the related factors of visual prognosis after operation. Results:At 1 month after operation, the differences in DRIL length ( χ2=52.194, P=0.000) and EZ fracture length ( F=9.558, P=0.000) among the three groups were statistically significant, but there was no significant difference in CMT ( F=0.817, P =0.447). At 1 and 3 months after operation, there were no significant differences in BCVA between the non-DRIL group and the DRIL≤500 μm group ( Z=-1.846, -2.224; P=0.195, 0.078), however, the BCVA of patients in non-DRIL group was better than that of patients in DRIL≤500μm group at 6 months after operation, and the difference was statistically significant ( Z=-2.508, P=0.036). The BCVA of patients in non-DRIL group at 1, 3 and 6 months after operation was better than that of patients in DRIL> 500 μm group, and there were significant differences ( Z=-5.992, -6.275, -6.497; P<0.01). The BCVA of the DRIL≤500 μm group was better than the DRIL> 500 μm group, and the differences were statistically significant ( Z=-4.260, -4.161, -4.099; P<0.01). The comparison of intra-group among the three groups showed that the BCVA of the non-DRIL group and the DRIL ≤ 500 μm group at 6 months after operation were higher than that at 1 month after operation, and the differences were statistically significant ( Z=-3.525, -3.420; P<0.01). There was no significant difference in BCVA between 6 months after operation and 1 month after operation in DRIL> 500 μm group ( Z=-0.422, P=0.673). The results of Spearman rank correlation analysis showed that a strong correlation was between the length of DRIL and logMAR BCVA at 1, 3 and 6 months after operation ( r s=0.896, 0.918, 0.940; P<0.01). The rupture length of EZ was moderately correlated with logMAR BCVA at 1, 3 and 6 months after operation ( r s=0.488, 0.502, 0.521; P<0.05). There was no significant correlation between CMT and logMAR BCVA at 1, 3 and 6 months after operation ( r s=0.243, 0.220, 0.193; P>0.05). Multivariate stepwise regression analysis showed that DRIL length was the main predictor of postoperative visual acuity recovery ( R2=0.703, P=0.000). Conclusion:The length of DRIL and the rupture length of EZ are correlated with the visual prognosis of patients with PDR after PPV, and there is a strong correlation between DRIL and postoperative visual acuity.