Spectral domain OCT can differentiate the retinal morphological changes of patients with Parkinson’s disease in clinical middle stages

The retinal morphological change has been detected in Parkinson’s disease. However, the previous studies had a controversial conclusion. The aim of this study was to observe the changes of retinal morphology in patients with Parkinson’s disease with different clinical stages based on Hoehn-Yahr stage by spectral domain optical coherence tomography (SD-OCT). Fifty-three PD patients and forty-one healthy controls (HC) were enrolled. Subjects were assessed for the retinal structure using SD-OCT and general ophthalmic examinations. The PD group was divided into three subgroups by the Hoehn and Yahr scale: H-Y I stage group, H-Y II stage group, and H-Y III stage group. The mean deviation of visual field had a significant difference among the four groups. The macular retinal thickness (MRT) and macular volume (MV) were obviously decreased in PD patients. And the further statistical analysis showed that the difference appeared between the H-Y III stage group and HC group. The other subgroups had no differences compared with the HC group. SD-OCT examination can detect the changes in retinal morphology in PD patients, and it may not be found the difference until the patients are in the H-Y III stage (the middle stage of PD).