Department of Neuroradiology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan.
Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan.
Neuroradiology. 2020 Nov;62(11):1433-1439. doi: 10.1007/s00234-020-02479-9. Epub 2020 Jun 18.
Machado-Joseph disease (MJD/SCA3) is the most frequent spinocerebellar ataxia worldwide. Pathological studies revealed less melanin-containing dopaminergic neurons in the substantia nigra (SN) pars compacta in MJD/SCA3 patients. The purpose of this study was to quantify the damage in the SN reported for MJD/SCA3 patients in vivo using neuromelanin MR imaging.
We retrospectively reviewed the clinical information and MR imaging in sixteen MJD/SCA3 patients and fourteen healthy controls. High-resolution T1-WI of the SN were acquired using a 3-T MR system. The neuromelanin-related contrast (NRC), which was defined as the number of pixels of high-signal-intensity areas on T1-WI in the SN, was calculated semi-automatically. The NRC values were compared between MJD/SCA3 patients and normal controls.
The NRC values were significantly lower in MJD/SCA3 patients than in healthy controls. In MJD/SCA3 patients, a significant negative correlation existed between disease durations and NRC values. No significant difference in the NRC values was revealed between the MJD/SCA3 patients with and without parkinsonism.
Neuromelanin in the SN may decrease at the early stage of the disease and continue to decrease over time with the disease duration in MJD/SCA3 patients. The NRC may be a useful biological index for monitoring MJD/SCA3.
马查多-约瑟夫病（MJD/SCA3）是全球最常见的脊髓小脑共济失调。病理学研究表明，MJD/SCA3 患者的黑质致密部（SN）中含黑色素的多巴胺能神经元较少。本研究旨在使用神经黑色素 MRI 对 MJD/SCA3 患者体内报道的 SN 损伤进行定量。
我们回顾性分析了 16 例 MJD/SCA3 患者和 14 名健康对照者的临床资料和 MRI 检查结果。使用 3T MR 系统采集 SN 的高分辨率 T1-WI。通过半自动化方法计算 SN 中 T1-WI 上高信号区域的像素数，即神经黑色素相关对比（NRC）。比较 MJD/SCA3 患者与正常对照组的 NRC 值。
MJD/SCA3 患者的 NRC 值明显低于健康对照组。在 MJD/SCA3 患者中，疾病持续时间与 NRC 值之间存在显著的负相关。MJD/SCA3 患者中有无帕金森病与 NRC 值之间无显著差异。
SN 中的神经黑色素可能在疾病早期就会减少，并随着疾病持续时间的延长而持续减少。NRC 可能是监测 MJD/SCA3 的有用生物学指标。
