Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Er Road, Shanghai 200025, China.
Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Er Road, Shanghai 200025, China.
Neuroimage. 2024 May 1;291:120588. doi: 10.1016/j.neuroimage.2024.120588. Epub 2024 Mar 26.
Parkinson's disease (PD) is associated with the loss of neuromelanin (NM) and increased iron in the substantia nigra (SN). Magnetization transfer contrast (MTC) is widely used for NM visualization but has limitations in brain coverage and scan time. This study aimed to develop a new approach called Proton-density Enhanced Neuromelanin Contrast in Low flip angle gradient echo (PENCIL) imaging to visualize NM in the SN.
This study included 30 PD subjects and 50 healthy controls (HCs) scanned at 3T. PENCIL and MTC images were acquired. NM volume in the SN pars compacta (SNpc), normalized image contrast (Cnorm), and contrast-to-noise ratio (CNR) were calculated. The change of NM volume in the SNpc with age was analyzed using the HC data. A group analysis compared differences between PD subjects and HCs. Receiver operating characteristic (ROC) analysis and area under the curve (AUC) calculations were used to evaluate the diagnostic performance of NM volume and CNR in the SNpc.
PENCIL provided similar visualization and structural information of NM compared to MTC. In HCs, PENCIL showed higher NM volume in the SNpc than MTC, but this difference was not observed in PD subjects. PENCIL had higher CNR, while MTC had higher Cnorm. Both methods revealed a similar pattern of NM volume in SNpc changes with age. There were no significant differences in AUCs between NM volume in SNpc measured by PENCIL and MTC. Both methods exhibited comparable diagnostic performance in this regard.
PENCIL imaging provided improved CNR compared to MTC and showed similar diagnostic performance for differentiating PD subjects from HCs. The major advantage is PENCIL has rapid whole-brain coverage and, when using STAGE imaging, offers a one-stop quantitative assessment of tissue properties.
帕金森病（PD）与黑质（SN）中神经黑色素（NM）的丧失和铁含量增加有关。磁化传递对比（MTC）广泛用于 NM 的可视化，但在脑覆盖范围和扫描时间方面存在局限性。本研究旨在开发一种新方法，称为低翻转角梯度回波中的质子密度增强神经黑色素对比（PENCIL）成像，以可视化 SN 中的 NM。
本研究纳入了 30 名 PD 患者和 50 名健康对照者（HCs），在 3T 上进行扫描。采集了 PENCIL 和 MTC 图像。计算了 SN 致密部（SNpc）中 NM 体积、归一化图像对比（Cnorm）和对比噪声比（CNR）。使用 HCs 的数据分析了 SNpc 中 NM 体积随年龄的变化。组分析比较了 PD 患者与 HCs 之间的差异。使用接收者操作特征（ROC）分析和曲线下面积（AUC）计算评估了 SNpc 中 NM 体积和 CNR 的诊断性能。
与 MTC 相比，PENCIL 提供了相似的 NM 可视化和结构信息。在 HCs 中，PENCIL 显示 SNpc 中的 NM 体积高于 MTC，但在 PD 患者中未观察到这种差异。PENCIL 具有更高的 CNR，而 MTC 具有更高的 Cnorm。两种方法都显示了 SNpc 中 NM 体积随年龄变化的相似模式。PENCIL 测量的 SNpc 中 NM 体积与 MTC 的 AUC 之间没有显著差异。这两种方法在这方面的诊断性能相当。
与 MTC 相比，PENCIL 成像提供了更高的 CNR，并且在区分 PD 患者和 HCs 方面具有相似的诊断性能。主要优势是 PENCIL 具有快速的全脑覆盖范围，并且当使用 STAGE 成像时，它提供了对组织特性的一站式定量评估。
