Abstract：
OBJECTIVE: Language dominance in the developing brain can vary widely across anatomical and pathological conditions as well as age groups. Repetitive navigated transcranial magnetic stimulation (rnTMS) has been applied to calculate the hemispheric dominance ratio (HDR) in adults. In this study, the authors aimed to assess the feasibility of using rnTMS to identify language lateralization in a pediatric neurosurgical cohort and to correlate the preoperative rnTMS findings with the postoperative language outcome.
METHODS: A consecutive prospectively collected cohort of 19 children with language-associated lesions underwent bihemispheric rnTMS mapping prior to surgery (100 stimulation sites on each hemisphere). In addition to feasibility and adverse effects, the HDR (ratio of the left hemisphere to right hemisphere error rate) was calculated. The anatomical surgical site and postoperative language outcome at 3 months after surgery were assessed according to clinical documentation.
RESULTS: Repetitive nTMS mapping was feasible in all 19 children (mean age 12.5 years, range 4-17 years; 16 left-sided lesions) without any relevant adverse events. Thirteen children (68%) showed left hemispheric dominance (HDR > 1.1), and 2 children (11%) showed right hemispheric dominance (HDR < 0.9). In 4 children (21%), the bihemispheric error rates were nearly the same (HDR ≥ 0.9 and ≤ 1.1). Sixteen children underwent surgery (14 tumor/lesion resections and 2 hemispherotomies) and 3 patients continued conservative therapy. After surgery, 4 patients (25%) showed an improvement in language function, 10 (63%) presented with stable language function, and 2 (12.5%) experienced deterioration in language function. Of the 6 patients with right hemispheric language involvement, 4 (80%) had glial tumors, 1 (20%) had focal cortical dysplasia, and 1 (20%) experienced hypoxic brain injury. Children with right hemispheric language involvement (HDR ≤ 1.1) did not show any language deterioration postoperatively.
CONCLUSIONS: Bihemispheric rnTMS language mapping as a noninvasive mapping technique to assess lateralization of language function in the pediatric neurosurgical population is safe and feasible. Why relevant right hemispheric language function (HDR ≤ 1.1) was associated with postoperative unaltered language function needs to be validated in future studies. Bihemispheric rnTMS language mapping strengthens risk-benefit considerations prior to pediatric tumor/epilepsy surgery in language-associated areas.
METHODS: A consecutive prospectively collected cohort of 19 children with language-associated lesions underwent bihemispheric rnTMS mapping prior to surgery (100 stimulation sites on each hemisphere). In addition to feasibility and adverse effects, the HDR (ratio of the left hemisphere to right hemisphere error rate) was calculated. The anatomical surgical site and postoperative language outcome at 3 months after surgery were assessed according to clinical documentation.
RESULTS: Repetitive nTMS mapping was feasible in all 19 children (mean age 12.5 years, range 4-17 years; 16 left-sided lesions) without any relevant adverse events. Thirteen children (68%) showed left hemispheric dominance (HDR > 1.1), and 2 children (11%) showed right hemispheric dominance (HDR < 0.9). In 4 children (21%), the bihemispheric error rates were nearly the same (HDR ≥ 0.9 and ≤ 1.1). Sixteen children underwent surgery (14 tumor/lesion resections and 2 hemispherotomies) and 3 patients continued conservative therapy. After surgery, 4 patients (25%) showed an improvement in language function, 10 (63%) presented with stable language function, and 2 (12.5%) experienced deterioration in language function. Of the 6 patients with right hemispheric language involvement, 4 (80%) had glial tumors, 1 (20%) had focal cortical dysplasia, and 1 (20%) experienced hypoxic brain injury. Children with right hemispheric language involvement (HDR ≤ 1.1) did not show any language deterioration postoperatively.
CONCLUSIONS: Bihemispheric rnTMS language mapping as a noninvasive mapping technique to assess lateralization of language function in the pediatric neurosurgical population is safe and feasible. Why relevant right hemispheric language function (HDR ≤ 1.1) was associated with postoperative unaltered language function needs to be validated in future studies. Bihemispheric rnTMS language mapping strengthens risk-benefit considerations prior to pediatric tumor/epilepsy surgery in language-associated areas.
摘要：
目的：发育中的大脑中的语言优势在解剖和病理条件以及年龄组之间差异很大。重复导航经颅磁刺激（rnTMS）已用于计算成年人的半球优势比（HDR）。在这项研究中,作者旨在评估在儿童神经外科队列中使用rnTMS识别语言偏侧化的可行性,并将术前rnTMS结果与术后语言结局相关联.
方法：连续前瞻性收集的19例语言相关病变患儿在手术前进行了双半球rnTMS定位（每个半球100个刺激部位）。除了可行性和不利影响，计算HDR(左半球与右半球的错误率之比)。根据临床文献评估手术后3个月的解剖手术部位和术后语言结果。
结果：在所有19名儿童（平均年龄12.5岁，范围4-17年；16个左侧病变）无任何相关不良事件。13名儿童（68％）表现出左半球优势（HDR>1.1），和2名儿童（11％）显示右半球优势（HDR<0.9）。4名儿童（21%）双半球错误率几乎相同(HDR≥0.9和≤1.1).16名儿童接受了手术（14例肿瘤/病变切除和2例半球切开术），3例患者继续保守治疗。手术后,4名患者（25％）表现出语言功能改善，10（63%）具有稳定的语言功能，2例（12.5％）语言功能恶化。在6例右半球语言受累的患者中，4（80％）有胶质肿瘤，1（20%）有局灶性皮质发育不良，1例(20%)发生缺氧性脑损伤。右半球语言受累（HDR≤1.1）的儿童术后未出现任何语言恶化。
结论：双半球rnTMS语言作图作为一种非侵入性作图技术来评估儿童神经外科人群语言功能的侧化是安全可行的。为什么相关的右半球语言功能（HDR≤1.1）与术后未改变的语言功能相关，需要在未来的研究中进行验证。双半球rnTMS语言映射在语言相关区域的小儿肿瘤/癫痫手术之前加强了风险收益考虑。
方法：连续前瞻性收集的19例语言相关病变患儿在手术前进行了双半球rnTMS定位（每个半球100个刺激部位）。除了可行性和不利影响，计算HDR(左半球与右半球的错误率之比)。根据临床文献评估手术后3个月的解剖手术部位和术后语言结果。
结果：在所有19名儿童（平均年龄12.5岁，范围4-17年；16个左侧病变）无任何相关不良事件。13名儿童（68％）表现出左半球优势（HDR>1.1），和2名儿童（11％）显示右半球优势（HDR<0.9）。4名儿童（21%）双半球错误率几乎相同(HDR≥0.9和≤1.1).16名儿童接受了手术（14例肿瘤/病变切除和2例半球切开术），3例患者继续保守治疗。手术后,4名患者（25％）表现出语言功能改善，10（63%）具有稳定的语言功能，2例（12.5％）语言功能恶化。在6例右半球语言受累的患者中，4（80％）有胶质肿瘤，1（20%）有局灶性皮质发育不良，1例(20%)发生缺氧性脑损伤。右半球语言受累（HDR≤1.1）的儿童术后未出现任何语言恶化。
结论：双半球rnTMS语言作图作为一种非侵入性作图技术来评估儿童神经外科人群语言功能的侧化是安全可行的。为什么相关的右半球语言功能（HDR≤1.1）与术后未改变的语言功能相关，需要在未来的研究中进行验证。双半球rnTMS语言映射在语言相关区域的小儿肿瘤/癫痫手术之前加强了风险收益考虑。
