The Evaluation of Corneal Innervation Using Corneal Confocal Microscopy

Czech version

Authors: I. Kovalová ^1,2; M. Horáková ^1,2; E. Vlčková ^1,2; M. Michalec ³; J. Raputová ^1,2; J. Bednařík ^1,2
Authors‘ workplace: Neurologická klinika LF MU a FN Brno ¹; CEITEC – Středoevropský technologický institut, MU, Brno ²; Oční klinika LF MU a FN Brno ³
Published in: Cesk Slov Neurol N 2017; 80/113(1): 49-57
Category: Original Paper
doi: https://doi.org/10.14735/amcsnn201749

Overview

Corneal confocal microscopy (CCM) is a novel noninvasive method enabling morphological evaluation of corneal structures including nerve fibers. These fibers are almost exclusively of A-delta and C type, i.e. small unmyelinated and poorly myelinated. CCM is thus used as a diagnostic tool for peripheral neuropathies and in particular small fiber neuropathy. The aim of this study was to introduce this method into clinical practice in the Czech Republic, to set-up appropriate normative data and to verify reproducibility of the method.

Material and methods:
A group of 71 healthy controls was examined using the CCM. The data were used to set normal values in three distinct age-related groups and compare these with CCM findings in a group of 54 patients with diabetic polyneuropathy (DPN). Fully-automated as well as expert manual analysis (by two evaluators) were used for quantification of nerve fiber densities, length and branches to verify reliability of the results.

Results:
CCM evaluation was easy, well-tolerated and time-efficient in the majority of patients/controls. Age-related normal values showed very good applicability in evaluated groups of healthy individuals and DPN patients. Compared to healthy controls, DPN patients showed highly significant changes of all the evaluated CCM parameters. Results by the two evaluators of the expert manual analysis showed very good reliability, while results from the automated analysis showed significantly lower values on the majority of the CCM parameters.

Conclusion:
The present study proved on a rather large cohort of healthy controls and a smaller sample of DPN patients that CCM is a easy to use, safe and reliable approach to evaluating corneal innervation. The data also highlighted the differences between automated analysis expert manual CCM analysis.

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers.

Key words:
confocal microscopy – cornea – small fiber neuropathy – diabetic neuropathies – reliability of results

Chinese summary - 摘要

激光共聚焦角膜神经支配的评价

显微镜

作者:

摘要

角膜的共焦显微镜（角膜的共焦显微镜; CCM）可以实现角膜IU的无创形态学可视化检查。因为角膜神经纤维是薄或小的髓鞘或没有髓鞘，所以CCM是一种SFN诊断方法，用于一般周围神经病变的检测。这样做的目的是为了引入临床检查的CCM神经系统的做法，在捷克共和国，设置适当的标准数据确定重复性测试。

患者和方法：

71名健康志愿者和54例糖尿病神经病患者（糖尿病神经病; DPN）进行了CCM检测。使用数据是

一套标准的三个不同年龄组。研究结果进行了自动评估和手动分析（由两个评价者独立地），以确定测试的可靠性。

结果：

CCM测试节省时间，运行稳定，并且绝大多数病人耐受性良好。年龄分层的标准数据显示

具有非常不错的人口实用性研究。与健康的CCM相比，DPN患者均已经表现出监测参数的显著变化。两名评估人员进行的手动分析也显示CCM具有很好的一致性，但监测参数的CCM值均显著下降。

结论：

本研究简单，安全和良好的证明通过角膜共焦显微镜测试角膜神经支配的可靠性，

一个包含健康对照和患者的DPN组的大样本研究表明，自动和手动评价的一致性。

关键词：

共聚焦显微镜 - 角膜 - 糖尿病神经病 - 结果的可靠性

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