Application of corneal confocal microscopy in patients with Parkinson disease and varying degrees of autonomic dysfunction
Objective To investigate the characteristics of corneal nerve fibers in patients with Parkinson disease(PD)and varying degrees of autonomic dysfunction by using corneal confocal microscopy(CCM).Methods A total of 70 patients with PD and 31 healthy controls were recruited.CCM was performed for all the patients enrolled,and accord-ing to the score of the Scale for Outcomes in Parkinson Disease for Autonomic Symptoms,the patients with PD were di-vided into mild autonomic dysfunction group and moderate to severe autonomic dysfunction group.CCM parameters and clinical data were compared between the two groups and the healthy control group.The receiver operating characteristic(ROC)curve analysis was used to quantify the efficacy of CCM parameters in the diagnosis of PD with varying degrees of autonomic dysfunction.Results The PD patients with mild autonomic dysfunction and those with moderate to severe auto-nomic dysfunction had significantly lower CNFD and CNFL than the healthy control group(P<0.05).In addition,the ROC curve analysis showed that CNFD among CCM parameters had a higher diagnostic value in distinguishing PD patients with moderate to severe autonomic nervous dysfunction from the healthy population,with an area under the ROC curve of 0.8224.Conclusion CCM can be used as an effective and objective detection method to investigate the characteristics of corneal nerve fibers in PD with varying degrees of autonomic dysfunction,which supplements the current research on the application of CCM technique in PD with small fiber neuropathy.