Axelson Hans W, Latini Francesco, Jemstedt Malin, Ryttlefors Mats, Zetterling Maria
Department of Medical Sciences, Section of Clinical Neurophysiology, Uppsala University, Uppsala, Sweden.
Department of Medical Sciences, Section of Neurosurgery, Uppsala University, Uppsala, Sweden.
Front Oncol. 2022 Aug 12;12:947119. doi: 10.3389/fonc.2022.947119. eCollection 2022.
Repetitive monopolar short-train stimulation (STS) delivered from a suction probe enables continuous mapping and distance assessment of corticospinal tracts during asleep glioma resection. In this study, we explored this stimulation technique in awake glioma surgery. Fourteen patients with glioma involving language-related tracts were prospectively included. Continuous (3-Hz) cathodal monopolar STS (five pulses, 250 Hz) was delivered the tip of a suction probe throughout tumor resection while testing language performance. At 70 subcortical locations, surgery was paused to deliver STS in a steady suction probe position. Monopolar STS influence on language performance at different subcortical locations was separated into three groups. Group 1 represented locations where STS did not produce language disturbance. Groups 2 and 3 represented subcortical locations where STS produced language interference at different threshold intensities (≥7.5 and ≤5 mA, respectively). For validation, bipolar Penfield stimulation (PS; 60 Hz for 3 s) was used as a "gold standard" comparison method to detect close proximity to language-related tracts and classified as positive or negative regarding language interference. There was no language interference from STS in 28 locations (Group 1), and PS was negative for all sites. In Group 2 (STS threshold ≥ 7.5 mA; median, 10 mA), there was language interference at 18 locations, and PS (median, 4 mA) was positive in only one location. In Group 3 (STS threshold ≤ 5 mA; median, 5 mA), there was language interference at 24 locations, and positive PS (median 4 mA) was significantly (p < 0.01) more common (15 out of 24 locations) compared with Groups 1 and 2. Despite the continuous stimulation throughout tumor resection, there were no seizures in any of the patients. In five patients, temporary current spread to the facial nerve was observed. We conclude that continuous subcortical STS is feasibly also in awake glioma surgery and that no language interference from STS or interference at ≥7.5 mA seems to indicate safe distance to language tracts as judged by PS comparisons. STS language interference at STS ≤ 5 mA was not consistently confirmed by PS, which needs to be addressed.
通过吸引探针进行重复单极短串刺激（STS）能够在胶质瘤切除术中持续绘制皮质脊髓束并评估其距离。在本研究中，我们在清醒状态下的胶质瘤手术中探索了这种刺激技术。前瞻性纳入了14例累及语言相关脑区的胶质瘤患者。在整个肿瘤切除过程中，通过吸引探针尖端施加连续（3赫兹）阴极单极STS（五个脉冲，250赫兹），同时测试语言功能。在70个皮质下位置，手术暂停，在吸引探针稳定位置施加STS。单极STS对不同皮质下位置语言功能的影响分为三组。第1组代表STS未产生语言干扰的位置。第2组和第3组代表皮质下位置，在这些位置STS在不同阈值强度下产生语言干扰（分别为≥7.5毫安和≤5毫安）。为了进行验证，双极彭菲尔德刺激（PS；60赫兹，持续3秒）被用作“金标准”比较方法，以检测与语言相关脑区的接近程度，并根据语言干扰分为阳性或阴性。28个位置的STS未产生语言干扰（第1组），所有这些位置的PS均为阴性。在第2组（STS阈值≥7.5毫安；中位数为10毫安）中，18个位置出现语言干扰，而PS（中位数为4毫安）仅在一个位置为阳性。在第3组（STS阈值≤5毫安；中位数为5毫安）中，24个位置出现语言干扰，与第1组和第2组相比，阳性PS（中位数4毫安）显著更常见（24个位置中的15个）（p<0.01）。尽管在整个肿瘤切除过程中持续进行刺激，但所有患者均未发生癫痫发作。在5例患者中，观察到电流暂时扩散至面神经。我们得出结论，在清醒状态下的胶质瘤手术中，连续皮质下STS也是可行的，并且根据PS比较判断，STS无语言干扰或≥7.5毫安时无干扰似乎表明与语言脑区有安全距离。STS≤5毫安时的语言干扰未被PS一致证实，这一问题需要解决。
