High myopia macular hole (MH) is a serious complication of high myopia. The main treatment method is surgery. Because of axial growth, posterior scleral staphyloma, choroidal atrophy and other factors, the operation is difficult, the anatomic reduction rate is low, and the visual prognosis is poor. How to improve the reduction rate of surgical dissection and the recovery of visual function is a hot topic. At present, the most popular surgeries include parsplanavitrectomy (PPV) and posterior scleral reinforcement (PSR). However, there are many controversies regarding the treatment of internal limiting membrane in PPV, the selection of vitreous gapfiller, the choice of reinforcement materials and reinforcement methods of PSR, and whether it is necessary to combine PPV and PSR, etc. In recent years, many new surgical methods or techniques have emerged, which significantly increase the success rate of MH.
Objective To observe the corneal nerve fibres damage in different stage of diabetic retinopathy (DR) with type 2 diabetes. Methods A cross-sectional study. One hundred and twenty eyes of 120 patients with type 2 diabetes served as diabetes group. According to International Clinical Diabetic Retinopathy Disease Severity Scales (2002), diabetes patients were classified into 4 subgroups: patients without diabetic retinopathy (NDR), patients with mild or moderate non-proliferative diabetic retinopathy (mNPDR), patients with severe non-proliferative diabetic retinopathy (sNPDR) and patients with proliferative diabetic retinopathy (PDR), each subgroup has 30 eyes of 30 patients. Another 30 eyes of 30 healthy participants served as control group. All eyes were scanned with HRT3 in vivo corneal confocal microscopy. Images of sub-basal nerve plexus were quantified including nerve fiber length (NFL), nerve fiber density (NFD), nerve fiber branch density (NFB), and nerve tortuosity (NT). The correlations of corneal nerve fiber with age, duration of diabetes and glycated hemoglobin (HbA1c) were analyzed using Spearman correlation analysis. Results NFL, NFD and NFB were found to be significantly lower in diabetic patients (F=147.315, 142.586, 65.898;P=0.000, 0.000, 0.000), NT was significantly greater in diabetic patients (F=39.431,P=0.000), when compared to control group. In diabetic patients, NFL, NFD and NFB were gradually reduced with DR severity, NT was gradually increased with DR severity. While the difference of NFL, NFD, NFB, NT was not statistically significant between sNPDR and PDR subgroups (P＞0.05), but was statistically significant between other subgroups (P＜0.05). Spearman correlation analysis results showed that age (r=－0.071, －0.080, 0.001, 0.100;P=0.391, 0.328, 0.991, 0.224) and HbA1c (r=－0.109, －0.115, －0.126, 0.025;P=0.238, 0.211, 0.169, 0.781) had no correlation with NFL, NFD, NFB, NT. Duration of diabetes was negatively correlated with the NFL, NFD (r=－0.212, －0.264;P= 0.020, 0.004), positive correlated with NT (r=0.261,P=0.004), and had no correlation with NFB (r=－0.119,P=0.194). Conclusions Corneal nerve fiber loss and nerve tortuosity increased were found in patients with type 2 diabetes, and even without diabetic retinopathy. The progress of corneal neuropathy was correlated with the severity of DR, but it was not change significantly between sNPDR and PDR.