[In vivo confocal microscopy observation and evaluation of sensation in diabetic corneas].
OBJECTIVE
To test the changes of corneal sensation in diabetic patients and to observe the diabetic corneas using confocal microscopy.


METHODS
One hundred and thirty-two diabetic patients were enrolled in this study. The diabetic history and medication were recorded. The FBG and HbA(1c) were checked for every patient. The patient's eye was systemically checked, including the IOP, visual acuity, cornea sensation, lenses, and the fundus. Two hundred patients of other diseases were enrolled as controls. The cornea of 85 patients and 56 controls were checked by the confocal microscopy. The right eyes of both patients and controls were used for analysis.


RESULTS
The cornea sensation of diabetic patients was significantly depressed as compared to that of the controls (P < 0.01). The depression of cornea sensation was related to the course of the disease, the presence of diabetic retinopathy and the degree of the diabetic retinopathy (P < 0.05). The confocal microscopy revealed that there was a higher corneal epithelium edema rate (11.76%) in diabetic patients than that of the controls (1.79%) (P < 0.05). The nerve fiber density of the diabetic patients was decreased and there were some morphological changes in the nerve fiber of diabetic patients, such as sparse, slim, less branches, less long fibers, edema and zigzag of the fibers.


CONCLUSIONS
The depression of the corneal sensation in diabetic patients is probably caused by the reduction and the degeneration of the corneal nerve fibers.
Liu
Xiao-wei
XW
Department of Ophthalmology, Peking Union Medical College Hospital, Eye Research Center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China. paddyliuxw@hotmail.com
Pang
Guo-xiang
GX
Wang
Zheng
Z
D000293:Adolescent; D000328:Adult; D000368:Aged; D003315:Cornea / Q000294:innervation* / Q000503:physiopathology; D003316:Corneal Diseases / Q000473:pathology* / Q000503:physiopathology; D003922:Diabetes Mellitus, Type 1 / Q000473:pathology* / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D012677:Sensation; D055815:Young Adult