目的:肿瘤功能平衡是神经肿瘤学的主要目标。导航经颅磁刺激(nTMS)的使用越来越多,可以对皮质功能解剖结构进行非侵入性表征,之前已经验证了其用于电机和语言映射的可靠性。到目前为止,尚未使用nTMS研究计算和算术处理。在这项研究中,作者提供了有关nTMS计算的初步数据。
方法:作者设计了一项单中心前瞻性研究,采用内部协议使用nTMS进行术前计划,包括算术处理。当清醒手术成为可能时,根据病人的情况,nTMS点用于指导直接皮层刺激(DCS),即,皮质绘图的黄金标准.基于导航TMS的纤维束造影用于手术计划。对nTMS和DCS点进行统计分析。
结果:从2021年2月到2023年10月,进行了61个用于nTMS计算映射的程序。临床评估,包括术前和术后评估(术后3个月),表现出良好的临床结局,保留了算术功能和恢复(92.8%的患者)。在清醒和睡眠手术组之间,术后临床结果在3个月随访时具有可比性,>90%的患者实现了改进的计算功能。所采用的手术策略旨在减少睡眠过程中的nTMS阳性点,而在清醒程序中,nTMS和DCS阳性点并未消除。总的来说,62%的计算功能阳性点通过开颅手术暴露,85%的人在手术过程中幸免。没有患者发生nTMS相关的癫痫发作。使用基于nTMS正点的扩散张量成像光纤跟踪进行计算。计算函数中涉及的白质纤维束是弓形束(56%)和额倾斜束(22%)。当在清醒手术中比较nTMS和DCS点时(n=10例患者),灵敏度为31.71%,特异性为85.76%,阳性预测值为22.41%,阴性预测值为90.64%,精度达到约69%。
结论:根据作者的初步数据,nTMS可以是研究认知功能的有利工具,旨在尽量减少神经损伤。接受nTMS手术的患者的术后临床效果非常好。考虑到这些结果,nTMS已被证明是绘制认知区域(包括计算功能)的可行方法。需要进一步的分析来验证这些数据。最后,其他认知功能(例如,视觉空间)可以用nTMS进行探索。
OBJECTIVE: The onco-functional balance represents the primary goal in neuro-oncology. The increasing use of navigated transcranial magnetic stimulation (nTMS) allows the noninvasive characterization of cortical functional anatomy, and its reliability for motor and language mapping has previously been validated. Calculation and arithmetic processing has not been studied with nTMS so far. In this study, the authors present their preliminary data concerning nTMS calculation.
METHODS: The authors designed a monocentric prospective study, adopting an internal protocol to use nTMS for preoperative planning, including arithmetic processing. When awake surgery was possible, according to the patients\' conditions, nTMS points were used to guide direct cortical stimulation (DCS), i.e., the gold standard for cortical mapping. Navigated TMS-based tractography was used for surgical planning. Statistical analyses on the nTMS and DCS points were performed.
RESULTS: From February 2021 to October 2023, 61 procedures for nTMS calculation mapping were performed. The clinical evaluation, including pre- and postoperative evaluations (3 months after surgery), demonstrated a good clinical outcome with preservation of arithmetic function and recovery (92.8% of patients). Between the awake and asleep surgery groups, the postoperative clinical results were comparable at the 3-month follow-up, with > 90% of the patients achieving improved calculation function. The surgical strategy adopted was aimed at sparing nTMS positive points in asleep procedures, whereas nTMS and DCS positive points were not removed in awake procedures. Overall, 62% of the positive points for calculation functions were exposed by craniotomy and 85% were spared during surgery. None of the patients developed nTMS-related seizures. Diffusion tensor imaging fiber tracking based on nTMS positive points for calculation was used. The white matter fiber tracts involved in calculation functions were the arcuate fasciculus (56%) and frontal aslant tract (22%). When nTMS and DCS points were compared in awake surgery (n = 10 patients), a sensitivity of 31.71%, specificity of 85.76%, positive predictive value of 22.41%, negative predictive value of 90.64%, and accuracy of approximately 69% were achieved.
CONCLUSIONS: Based on the authors\' preliminary data, nTMS can be an advantageous tool to study cognitive functions, aimed at minimizing neurological impairment. The postoperative clinical outcome for patients who underwent operation with nTMS was very good. Considering these results, nTMS has proved to be a feasible method to map cognitive areas including those for calculation functions. Further analyses are needed to validate these data. Finally, other cognitive functions (e.g., visuospatial) may be explored with nTMS.