Department of Radiosurgery and Stereotactic Radiotherapy, MediClin Robert Janker Clinic and MediClin MVZ Bonn, Villenstraße 8, 53129, Bonn, Germany.
Department of Neurosurgery, Division of Functional Neurosurgery, Stereotaxy and Neuromodulation, University Hospital of Bonn, Sigmund-Freud-Straße 25, 53105, Bonn, Germany.
Strahlenther Onkol. 2018 Dec;194(12):1103-1113. doi: 10.1007/s00066-018-1317-z. Epub 2018 May 23.
Data concerning the clinical usefulness of steady-state sequences (SSS) for vestibular schwannomas (VS) after linear accelerator (LINAC) stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) are scarce. The aim of the study was to investigate whether SSS provide an additional useful follow-up (FU) tool to the established thin-layered T1 sequences with contrast enhancement.
Pre- and post-treatment SSS were identified in 45 consecutive VS patients (2012-2016) with a standardized FU protocol including SSS at 2-3 months and 6 months/yearly in our prospective database and were retrospectively re-evaluated. The SSS were used throughout for the segmentation of the cochlea and partly of the trigeminal nerve in the treatment planning. Data analysis included signal conversion in SSS and possible correlation with neuro-otological outcome and volumetric assessment after a certain time interval.
The series included 42 SRS and 3 SRT patients (31 female/14 male; mean age 59.3 years, range: 25-81 years). An SSS signal conversion was observed in 20 tumors (44.4%) within a mean time of 11 months (range: 7-15 months). Mean FU time was 26 months (median of 4 FU visits) and demonstrated tumor volume shrinkage in 29 cases (64.4%) correlating with FU time (p = 0.07). The incidence rate of combined shrinkage and signal conversion (48.3%) compared to those without signal conversion (51.7%) did not differ significantly (p = 0.49). In case of an early signal conversion at the first FU, a weak statistical significance (p = 0.05) for a higher shrinkage rate of VS with signal conversion was found. Side effects in cases with signal conversion (9/20, 45%) were more frequently than without signal conversion (6/25, 24%) without reaching statistical significance (p = 0.13).
Our data confirmed the usefulness of SSS for anatomical segmentation of VS in LINAC-SRS/SRT treatment planning and add data supporting their potential as an adjunctive FU option in VS patients.
关于直线加速器（LINAC）立体定向放射外科（SRS）或立体定向放疗（SRT）后，稳态序列（SSS）对前庭神经鞘瘤（VS）的临床应用价值的数据较为匮乏。本研究旨在探讨 SSS 是否为一种比增强薄层 T1 序列更有价值的随访（FU）工具。
在我们的前瞻性数据库中，通过标准化 FU 方案（包括 SSS 在 2-3 个月和 6 个月/年）识别了 45 例连续 VS 患者（2012-2016 年）的治疗前后 SSS，并进行了回顾性重新评估。SSS 用于整个耳蜗和部分三叉神经的分割，用于治疗计划。数据分析包括 SSS 中的信号转换，并与神经耳科学结果和一定时间间隔后的体积评估相关联。
该系列包括 42 例 SRS 和 3 例 SRT 患者（31 名女性/14 名男性；平均年龄 59.3 岁，范围：25-81 岁）。在平均 11 个月（范围：7-15 个月）内，观察到 20 个肿瘤（44.4%）的 SSS 信号转换。平均 FU 时间为 26 个月（中位数 4 次 FU 就诊），在 29 例（64.4%）中显示肿瘤体积缩小，与 FU 时间相关（p=0.07）。与没有信号转换的肿瘤相比，发生信号转换（48.3%）和肿瘤体积缩小（51.7%）的发生率没有显著差异（p=0.49）。在第一次 FU 出现早期信号转换的情况下，发现有信号转换的 VS 肿瘤体积缩小率更高，具有统计学意义（p=0.05）。有信号转换的病例（9/20，45%）的副作用比没有信号转换的病例（6/25，24%）更常见，但没有达到统计学意义（p=0.13）。
我们的数据证实了 SSS 在 LINAC-SRS/SRT 治疗计划中对 VS 解剖学分割的有用性，并提供了支持其作为 VS 患者附加 FU 选择的潜在价值的数据。
