角膜激光共焦显微镜对糖尿病周围神经病变的早期诊断

Early diagnosis of diabetic peripheral neuropathy by corneal confocal microscopy

目的通过角膜激光共焦显微镜研究角膜神经的改变与糖尿病周围神经病变(DPN)的相关性。方法入选45例2型糖尿病(T2DM)患者,其中合并DPN组25例,不伴DPN组20例,另选年龄相匹配的正常对照(NC)组10名,采用角膜激光共焦显微镜观察并记录受检者角膜上皮下神经的形态结构情况。结果 NC组的角膜上皮下神经较直,分支较少。糖尿病不伴DPN组角膜上皮下神经纤维长度与NC组相比无明显差异,但神经曲折度显著增加(P<0.05),神经分支密度亦明显增加(P<0.05)。而糖尿病合并DPN组的神经纤维长度相比于NC组、糖尿病不伴DPN组均显著减少,同时神经曲折度进一步增加,神经分支密度显著降低。结论糖尿病患者在周围神经病变的不同时期均有角膜上皮下神经的变化,提示使用角膜激光共焦显微镜进行角膜上皮下神经的形态结构观察对DPN的早期诊断有一定的价值。

Objective To define the relationship between alterations in the early corneal innervation using laser confocal microscopy and diabetic peripheral neuropathy severity. Methods Forty-five type 2 diabetic patients stratified into diabetic peripheral neuropathy （DPN）, non- diabetic peripheral neuropathy （NDPN） and 10 age-matched healthy subjects were studied. Subbasal nerves were investigated by laser confocal microscopy. Results Corneal nerve fiber length （NFL） was significantly decreased in DPN group when compared with control group and NDPN group （P〈0.05）. Nerve branch density （NBD） was increased in NDPN group, but greatly decreased in DPN group when compared with control group （P〈 0.05）. Tortuosity coefficient （TC） was significantly increased in in NDPN group, and further increased in DPN group （P〈0.05）. Conclusions Patients with diabetes show alterations in corneal innervations in different peripheral neuropathic stages. Corneal confocal microscopy can be used for early diagnosis of diabetic peripheral neuropathy.