Crockett Rachel A, Wilkins Kevin B, Zeineh Michael M, McNab Jennifer A, Henderson Jaimie M, Buch Vivek P, Brontë-Stewart Helen M
Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, United States.
Department of Radiology, Stanford University School of Medicine, Stanford, CA, United States.
Imaging Neurosci (Camb). 2024;2. doi: 10.1162/imag_a_00067. Epub 2024 Jan 11.
At the center of the cortical cholinergic network, the nucleus basalis of Meynert (NBM) is crucial for the cognitive domains most vulnerable in Parkinson's disease (PD). Preclinical evidence has demonstrated the positive impact of NBM deep brain stimulation (DBS) on cognition but early human trials have had mixed results. It is possible that DBS of the lateral NBM efferent white matter fiber bundle may be more effective at improving cognitive-motor function. However, precise tractography modelling is required to identify the optimal target for neurosurgical planning. Individualized tractography approaches have been shown to be highly effective for accurately identifying DBS targets but have yet to be developed for the NBM.
Using structural and diffusion-weighted imaging, we developed a tractography pipeline using manually segmented regions of interest for precise individualized identification of the lateral NBM target tract. Using dice similarity coefficients, the reliability of the tractography outputs was assessed across three cohorts to investigate: 1) whether this manual segmentation pipeline is more reliable than an existing automatic segmentation pipeline currently used in the literature; 2) the inter- and intra-rater reliability of our pipeline in research scans of patients with PD; and 3) the reliability and practicality of this pipeline in clinical scans of DBS patients.
The individualized manual pipeline was found to be significantly more reliable than the existing automated pipeline for both the segmentation of the NBM region itself (p < 0.001) and the reconstruction of the target lateral tract (p = 0.002). There was also no significant difference between the reliability of two different raters in the PD cohort (p = 0.25), which showed high inter- (mean Dice coefficient >0.6) and intra-rater (mean Dice coefficient >0.7) reliability across runs. Finally, the pipeline was shown to be highly reliable within the clinical scans (mean Dice coefficient = 0.77). However, accurate reconstruction was only evident in 7/10 tracts.
We have developed a reliable tractography pipeline for the identification and analysis of the NBM lateral tract in research and clinical-grade imaging of healthy young adult and PD patient scans.
在皮质胆碱能网络的中心，梅纳特基底核（NBM）对于帕金森病（PD）中最易受损的认知领域至关重要。临床前证据已证明NBM深部脑刺激（DBS）对认知有积极影响，但早期人体试验结果不一。外侧NBM传出白质纤维束的DBS在改善认知运动功能方面可能更有效。然而，需要精确的纤维束成像建模来确定神经外科手术规划的最佳靶点。个体化纤维束成像方法已被证明能非常有效地准确识别DBS靶点，但尚未针对NBM开发。
利用结构和扩散加权成像，我们开发了一种纤维束成像流程，使用手动分割的感兴趣区域来精确个体化识别外侧NBM目标纤维束。使用骰子相似系数，在三个队列中评估纤维束成像输出的可靠性，以研究：1）这种手动分割流程是否比文献中目前使用的现有自动分割流程更可靠；2）我们的流程在PD患者研究扫描中的评分者间和评分者内可靠性；3）该流程在DBS患者临床扫描中的可靠性和实用性。
发现个体化手动流程在NBM区域本身的分割（p < 0.001）和目标外侧纤维束的重建（p = 0.002）方面均比现有的自动流程显著更可靠。在PD队列中，两名不同评分者的可靠性之间也没有显著差异（p = 0.25），在各次运行中显示出高评分者间（平均骰子系数>0.6）和评分者内（平均骰子系数>0.7）可靠性。最后，该流程在临床扫描中显示出高度可靠性（平均骰子系数 = 0.77）。然而，准确重建仅在10条纤维束中的7条中明显。
我们已经开发了一种可靠的纤维束成像流程，用于在健康年轻成年人和PD患者扫描的研究及临床级成像中识别和分析NBM外侧纤维束。
