目的:分析降糖治疗对糖尿病患者眼屈光度的影响。方法:新诊断的糖尿病患者20例,检测治疗前血糖、糖化血红蛋白(HbA1c)、空腹及餐后2h C肽。测定双眼屈光度、角膜曲率、前房深度及晶状体厚度,并在降糖治疗1,2,3,4wk分别复测以上眼部指标。分析屈光度改变与各生化指标的相关性及降糖治疗前后各眼部指标的变化。结果:降糖治疗后所有患者均出现远视性屈光改变,改变幅度与HbA1c和治疗1wk的降糖速度呈正相关,与治疗前血糖、空腹及餐后2h C肽无相关性,持续约2 ~4wk逐渐恢复至治疗前屈光水平。治疗前后,角膜曲率、前房深度和晶状体厚度等未见显著性变化。结论:降糖治疗导致糖尿病患者出现暂时性远视改变,改变幅度主要取决于治疗前HbA1c水平及前7d的降糖速度。其发生机制可能与晶状体水合化导致的屈光力降低有关,而非晶状体形态的改变。

AIM: To evaluate the effects of glycemic control on refraction in diabetic patients. METHODS: Twenty newly diagnosed diabetic patients were included in this study. The random blood glucose, HbA1c levels, fasting C-peptide and postprandial 2h C-peptide were measured before treatment. The patients with random blood glucose higher than 12.0mmol/L and HbA1c level higher than 10.0% were selected. Refraction, intraocular pressure, radius of the anterior corneal curvature, depth of the anterior chamber, lens thickness, vitreous length, and axial length were measured on admission and at the end of week 1, 2, 3 and 4 during glycemic control. RESULTS: A transient hyperopic change occurred in all the patients receiving glycemic control. The maximum hyperopic change was 1.60D (range 0.50±3.20D). Recovery of the previous refraction occurred between two and four weeks after insulin treatment. There was a positive correlation between the maximum hyperopic changes and the HbA1c levels on admission (r=0.84, P<0.05). There was a positive correlation between the maximum hyperopic changes and the daily rate of blood glucose reduction over the first 7 days of the treatment (r=0.53, P<0.05). During transient hyperopia, no significant changes were observed in the intraocular pressure, radius of the anterior corneal curvature, depth of the anterior chamber, lens thickness, vitreous length and axial length. CONCLUSION: Transient hyperopic changes occur after glycemic control in diabetic patients with severe hyperglycemia. The degrees of transient hyperopia are highly dependent on HbA1c levels before treatment and the rate of reduction of the blood glucose level.