方法：对52例HbA1c>7%的2型糖尿病患者行单中心、前瞻性临床试验。结果显示，平均随访6mo后，血糖浓度控制效果不佳。记录性别、病程，采用超声波测厚仪测量中央角膜厚度，取三次测量的平均值。患者在内分泌科门诊进行治疗。当HbA1c≤7%时，再次记录中央角膜厚度，并比较治疗前后的HbA1c水平和中央角膜厚度。

结果：治疗前后平均中央角膜厚度分别为552.30±29.26μm和542.36±27.20μm，平均HbA1c水平分别为(9.36±1.79)%和(6.45±0.70)%，差异显著(P=0.0001，配对t检验)。

结论：中央角膜厚度随HbA1c水平的降低(血糖控制良好)而显著下降，但高血糖和正常血糖患者中央角膜厚度平均值均在正常范围内。因此，在对糖尿病患者进行眼部检查时应注意HbA1c。

METHODS: Single-centre, prospective, clinical trial with a mean of 6-month follow-up examination. We included 52 patients with type 2 diabetes mellitus(DM)whose HbA1c levels were above 7%, indicating poor glycemic control. Sex of patients, and duration of DM were recorded. CCT was determined with ultrasound pachymeter. Each CCT measurement was the mean of 3 pachymeter readings. Then the patients were treated by the endocrinology clinic. When glycemic control was achieved(HbA1c≤7%), CCT measurements were recorded again. HbA1c and CCT before and after treatment were compared.

RESULTS: Mean CCT before treatment was 552.30±29.26μm, and mean HbA1c was(9.36±1.79)%. Mean CCT after treatment was 542.36±27.20μm, and mean HbA1c was(6.45±0.70)%. The difference between these two values was statistically significant(P=0.0001, paired t test).

CONCLUSION: Even though mean hyperglycemic and euglycemic CCT measurements were in normal range, CCT decreases significantly by lowering HbA1c level(good glycemic control). Therefore, glycemic status(HbA1c)should be considered when examining the eye of diabetic patients.