Dorsal hyperintensity and iron deposition patterns in the substantia nigra of Parkinson’s disease, idiopathic REM sleep behavior disorder, and Parkinson-plus syndromes at 7T MRI: a prospective diagnostic study by Dongning Su & Zhijin Zhang & Zhe Zhang & Rui Yan & Wanlin Zhu & Ning Wei & Yue Suo & Xinyao Liu & Ying Jiang & Lingyan Ma & Huiqing Zhao & Zhan Wang & Xuemei Wang & Huizi Ma & Xin Liu & Chaodong Wang & Zhirong Wan & Fangfei Li & Yuan Li & Joyce S. T.... instant download

Dorsal hyperintensity and iron deposition patterns in the substantia nigra of Parkinson’s disease, idiopathic REM sleep behavior disorder, and Parkinson-plus syndromes at 7T MRI: a prospective diagnostic study by Dongning Su & Zhijin Zhang & Zhe Zhang & Rui Yan & Wanlin Zhu & Ning Wei & Yue Suo & Xinyao Liu & Ying Jiang & Lingyan Ma & Huiqing Zhao & Zhan Wang & Xuemei Wang & Huizi Ma & Xin Liu & Chaodong Wang & Zhirong Wan & Fangfei Li & Yuan Li & Joyce S. T.... instant download

Translational Neurodegeneration,AbstractBackground Dorsal nigral hyperintensity (DNH) abnormality associated with excessive iron deposition in the substantia nigra, is recognized as an imaging characteristic of Parkinson’s disease (PD) and can be efectively visualized using 7T MRI. This study was aimed to develop and validate the optimal DNH assessment method as a biomarker for PD, idiopathic rapid eye movement sleep behavior disorder (iRBD), and Parkinson-plus syndromes, and to explore the nigral iron deposition patterns in these diseases.Methods Three-dimensional gradient-echo T2*-weighted images were acquired by 7T MRI from a total of 402 patients and 100 healthy controls (HCs) in two independent cohorts (development and validation cohorts). Seven methods, including four dichotomous methods and three DNH rating scales, were used to assess DNH and evaluate their diagnostic performance. R2* mapping and principal component analysis were performed to assess nigral iron deposition patterns.Results Bilateral DNH detection rates in the development cohort were 22.6% for early-stage PD, 3.7% for advanced PD, 93.5% for iRBD, 5.7% for MSA-parkinsonian type, 78.8% for MSA-cerebellar type, 11.8% for progressive supranuclear palsy (PSP), and 100% for HC, with similar rates in the validation cohort. A cut-of of 6 on the 6-point visibility scale demonstrated a 100% accuracy for diagnosing early-stage PD in both the development and the validation cohorts. This scale exhibited moderate diferential diagnostic performance between early-stage PD and iRBD (area under the curve [AUC]=0.940) or MSA-C (AUC=0.892). Iron deposition was predominantly in the dorsal and posterior