Department of Neurosurgery, University of Heidelberg, Heidelberg, Germany.
German Cancer Research Center, Division of Medical Image Computing, Heidelberg, Germany.
World Neurosurg. 2022 Feb;158:e429-e440. doi: 10.1016/j.wneu.2021.11.006. Epub 2021 Nov 9.
Fiber tractography (FT) has become an important noninvasive tool to ensure maximal safe tumor resection in eloquent glioma surgery. Intraoperatively applied FT is still predominantly based on diffusion tensor imaging (DTI). However, reconstruction schemes of high angular resolution diffusion imaging data for high-resolution FT (HRFT) are gaining increasing attention. The aim of this prospective study was to compare the accuracy of sophisticated HRFT models compared with DTI-FT.
Ten patients with eloquent gliomas underwent surgery under awake craniotomy conditions. The localization of acquisition points, representing deteriorations during intraoperative electrostimulation (IOM) and neuropsychological mapping, were documented. The offsets of acquisition points to the respective fiber bundle were calculated. Probabilistic Q-ball imaging (QBI) and constrained spherical deconvolution (CSD)-FT were compared with DTI-FT for the major language-associated fiber bundles (superior longitudinal fasciculus [SLF] II-IV, inferior fronto-occipital fasciculus, and inferior longitudinal fasciculus/medial longitudinal fasciculus).
Among 186 offset values, 46% were located closer than 10 mm to the estimated fiber bundle (CSD, 36%; DTI, 40% and QBI, 60%). Moreover, only 10 offsets were further away than 30 mm (5%). Lowest mean minimum offsets (SLF, 7.7 ± 7.9 mm; inferior fronto-occipital fasciculus, 12.7 ± 8.3 mm; inferior longitudinal fasciculus/medial longitudinal fasciculus, 17.7 ± 6.7 mm) were found for QBI, indicating a significant advantage compared with CSD or DTI (P < 0.001), respectively. No significant differences were found between CSD-FT and DTI-FT offsets (P = 0.105), albeit for the compound SLF exclusively (P < 0.001).
Comparing HRFT techniques QBI and CSD with DTI, QBI delivered significantly better results with lowest offsets and good correlation to IOM results. Besides, QBI-FT was feasible for neurosurgical preoperative and intraoperative applications. Our findings suggest that a combined approach of QBI-FT and IOM under awake craniotomy is considerable for best preservation of neurological function in the presented setting. Overall, the implementation of selected HRFT models into neuronavigation systems seems to be a promising tool in glioma surgery.
纤维束追踪（FT）已成为确保在语言相关胶质瘤手术中进行最大安全肿瘤切除的重要无创工具。术中应用的 FT 仍然主要基于弥散张量成像（DTI）。然而，用于高分辨率 FT（HRFT）的高角分辨率扩散成像数据的重建方案越来越受到关注。本前瞻性研究的目的是比较复杂 HRFT 模型与 DTI-FT 的准确性。
10 例语言相关胶质瘤患者在清醒开颅手术条件下接受手术。记录术中电刺激（IOM）和神经心理学映射过程中出现恶化时采集点的定位。计算采集点与各自纤维束的偏移量。比较概率球内成像（QBI）和约束球内解卷积（CSD）-FT 与 DTI-FT 在主要语言相关纤维束（上纵束[SLF] II-IV、下额枕束和下纵束/内侧纵束）中的应用。
在 186 个偏移值中，46%的偏移值距离估计纤维束的距离小于 10mm（CSD 为 36%；DTI 为 40%，QBI 为 60%）。此外，只有 10 个偏移值大于 30mm（5%）。QBI 的最小平均最小偏移值最低（SLF，7.7±7.9mm；下额枕束，12.7±8.3mm；下纵束/内侧纵束，17.7±6.7mm），与 CSD 或 DTI 相比具有显著优势（P<0.001）。CSD-FT 和 DTI-FT 偏移值之间无显著差异（P=0.105），尽管在复合 SLF 中存在显著差异（P<0.001）。
将 HRFT 技术 QBI 和 CSD 与 DTI 进行比较，QBI 提供了更好的结果，其偏移值最低，与 IOM 结果相关性良好。此外，QBI-FT 可用于神经外科术前和术中应用。我们的研究结果表明，在清醒开颅术中联合使用 QBI 和 IOM 可以更好地保护神经功能。总的来说，将选定的 HRFT 模型纳入神经导航系统似乎是胶质瘤手术中一种很有前途的工具。
