Objective To observe the changes in the biomechanical properties of the cornea of diabetic retinopathy (DR), and analyze its relationship with the degree of DR. Methods A retrospective study. From September 2020 to February 2021, 83 patients with type 2 diabetes (T2DM) combined with DR treated in the Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, 83 eyes (DR group), 30 patients with T2DM without DR recruited from the outpatient clinic 30 eyes (NDR group) and 30 eyes of non-diabetes patients (NDM group) were included in the study. All left eyes were chose as the study eye. Among the 83 eyes in the DR group, 39 eyes were non-proliferative DR (NPDR) and 44 eyes were proliferative DR (PDR). Based on this, they were divided into NPDR group and PDR group. There was no statistically significant difference in age (t=1.10) and sex ratio (χ²=0.46) among patients in the DR group, NDR group, and NDM group (P>0.05); body mass index (t=3.74), glycosylated hemoglobin (t=35.02) and the length of the eye axis (t=5.51), the difference was statistically significant (P<0.05). The eye response analyzer (ORA) was used to measure the corneal hysteresis (CH), corneal resistance factor (CRF), Goldman related intraocular pressure (IOPg), and corneal compensatory intraocular pressure (IOPcc). The corneal topography was used to measure the central corneal thickness (CCT) of the examined eye. The differences of CCT, IOPcc, IOPg, CH, CRF among multiple groups were compared by one-way analysis of variance. Multiple linear regression was used to analyze the relationship between CH, CRF and related influencing factors in DR patients. Results There were statistically significant differences in CCT, IOPcc, IOPg, CH, and CRF among the eyes of the DR group, NDR group, and NDM group (F=3.71, 5.60, 9.72, 9.02, 21.97; P<0.05). Pairwise comparisons were between groups, CH, CRF: the difference between the DR group and the NDM group and the NDR group was statistically significant (P<0.05); CCT: the difference between the DR group and the NDM group was statistically significant (P<0.05), and The difference in the NDR group was not statistically significant (P>0.05). CCT, CH, CRF: the difference between the NDR group and the NDM group was not statistically significant (P>0.05). The results of multiple linear regression analysis showed that CCT and IOPcc in DR patients were independent influencing factors of CH [CCT: β=0.01, 95% confidence interval (CI) 0.01-0.03, P=0.013; IOPcc: β=－0.15, 95%CI －0.25-－0.05, P=0.005]; Age, CCT, IOPcc were independent influencing factors of CRF [Age: β=－0.06, 95%CI －0.09-－0.03, P＜0.001; CCT: β=0.01, 95%CI 0.00-0.02, P=0.049; IOPcc: β=0.16, 95%CI 0.07-0.25, P=0.001]. The comparison of CCT, CH, CRF, adjusted CH, and adjusted CRF of the eyes in the NDR group, NPDR group, and PDR group were statistically significant (F=3.76, 5.36, 12.61, 6.59, 10.41; P<0.05). Pairwise comparison between groups, CH, CRF, adjusted CH, adjusted CRF: the difference between the NPDR group, the PDR group and the NDR group was statistically significant (P<0.05), and the difference between the PDR group and the NPDR group was not statistically significant (P>0.05); CCT: The difference between NPDR group and NDR group, PDR group and NPDR group was not statistically significant (P>0.05), and the difference between PDR group and NDR group was statistically significant (P<0.05). Conclusion The CH and CRF of eyes with T2DM and DR are elevated; CCT and IOPcc are independent influencing factors of CH, and age, CCT and IOPcc are independent influencing factors of CRF.

Citation： Du Zhiqiang, Sun Jingru, Dong Yichen, Wan Guangming. Study on corneal biomechanical properties in eyes with diabetic retinopathy. Chinese Journal of Ocular Fundus Diseases, 2022, 38(1): 14-19. doi: 10.3760/cma.j.cn511434-20210929-00558 Copy