AUTHOR=Xu Bei , Wang Xin , Guo Jifeng , Xu Huizhuo , Tang Beisha , Jiao Bin , Shen Lu 

TITLE=Retinal Microvascular Density Was Associated With the Clinical Progression of Parkinson’s Disease

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=Volume 14 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2022.818597

DOI=10.3389/fnagi.2022.818597

ISSN=1663-4365

ABSTRACT=Background: Retinal microvascular density has been studied in neurodegenerative diseases, whereas patients with Parkinson’s disease (PD) at different clinical stages have been rarely investigated. The present study aimed to evaluate the microvascular variations in superficial retinal capillary plexus (SCP) in patients with PD on different Hoehn-Yahr (H-Y) stage by optical coherence tomography angiography (OCTA), as well as determine their relationships with clinical parameters. 
Methods:115 PD patients and 67 healthy controls (HC) were recruited. The PD group was divided into three groups based on H-Y stage. The OCTA examination was performed in all participants, and the macular vessel density (m-VD), peripapillary vessel density (p-VD) and foveal avascular zone (FAZ) area was measured. 
Results: The m-VD in all regions, p-VD in center [6.10 (4.80, 6.95) mm-1 in healthy eyes vs 5.10 (3.70, 6.40) mm-1 in patients], nasal inner (NI) [18.50 (17.80, 19.30) mm-1 in healthy eyes vs 17.90 (17.10, 18.70) mm-1 in patients], temporal outer (TO) [19.60 (18.90, 20.20) mm-1 in healthy eyes vs 19.30 (18.50, 19.70) mm-1 in patients] regions and FAZ area [0.36 (0.32, 0.39) mm2 in healthy eyes vs 0.29 (0.26, 0.33) mm2 in patients] noticeably decreased in PD groups compared with HC (p＜0.05). Moreover, FAZ area was suggested to decline significantly in PD patients with H-Y I stage (p＜0.05), while which was more serious in H-Y III stage in patients. Furthermore, we found that m-VD exhibited a significant negative correlation with age, disease duration, UPDRS scores, NMSS scores and H-Y stage. 
Conclusion: OCTA has the potential to non-invasively detect the microvascular changes in PD patients with different clinical stages in vivo, and it may be a valuable tool to monitor the PD progression.