Neurosciences Institute, Seattle Children's Hospital, United States; Center for Integrated Brain Research Seattle Children's, United States.
Radiology, Seattle Children's Hospital, United States.
Epilepsy Behav. 2022 Jan;126:108461. doi: 10.1016/j.yebeh.2021.108461. Epub 2021 Dec 9.
Clinically employable functional MRI (fMRI) memory paradigms are not yet established for pediatric patient epilepsy surgery workups. Seeking to establish such a paradigm, we evaluated the effectiveness of memory fMRI tasks we developed by quantifying individual activation in a clinical pediatric setting, analyzing patterns of activation relative to the side of temporal lobe (TL) pathology, and comparing fMRI and Wada test results.
We retrospectively identified 72 patients aged 6.7-20.9 years with pathology (seizure focus and/or tumor) limited to the TL who had attempted memory and language fMRI tasks over a 9-year period as part of presurgical workups. Memory fMRI tasks required visualization of autobiographical memories in a block design alternating with covert counting. Language fMRI protocols involved verb and sentence generation. Scans were both qualitatively interpreted and quantitatively assessed for blood oxygenation level dependent (BOLD) signal change using region of interest (ROI) masks. We calculated the percentage of successfully scanned individual cases, compared 2 memory task activation masks in cases with left versus right TL pathology, and compared fMRI with Wada tests when available. Patients who had viable fMRI and Wada tests had generally concordant results.
Of the 72 cases, 60 (83%), aged 7.6-20.9 years, successfully performed the memory fMRI tasks and 12 (17%) failed. Eleven of 12 unsuccessful scans were due to motion and/or inability to perform the tasks, and the success of a twelfth was indeterminate due to orthodontic metal artifact. Seven of the successful 60 cases had distorted anatomy that precluded employing predetermined masks for quantitative analysis. Successful fMRI memory studies showed bilateral mesial temporal activation and quantitatively demonstrated: (1) left activation (L-ACT) less than right activation (R-ACT) in cases with left temporal lobe (L-TL) pathology, (2) nonsignificant R-ACT less than L-ACT in cases with right temporal lobe (R-TL) pathology, and (3) lower L-ACT plus R-ACT activation for cases with L-TL versus R-TL pathology. Patients who had viable fMRI and Wada tests had generally concordant results.
This study demonstrates evidence of an fMRI memory task paradigm that elicits reliable activation at the individual level and can generally be accomplished in clinically involved pediatric patients. This autobiographical memory paradigm showed activation in mesial TL structures, and cases with left compared to right TL pathology showed differences in activation consistent with extant literature in TL epilepsy. Further studies will be required to assess outcome prediction.
目前还没有为儿科癫痫手术患者建立临床可用的功能磁共振成像（fMRI）记忆范式。为了建立这样的范式，我们通过量化临床儿科环境下的个体激活来评估我们开发的记忆 fMRI 任务的有效性，分析相对于颞叶（TL）病变侧的激活模式，并比较 fMRI 和 Wada 测试结果。
我们回顾性地确定了 72 名年龄在 6.7-20.9 岁之间的患者，这些患者的病理学（癫痫发作焦点和/或肿瘤）仅限于 TL，他们在 9 年内尝试了记忆和语言 fMRI 任务，作为术前评估的一部分。记忆 fMRI 任务要求在块设计中可视化自传体记忆，与隐蔽计数交替进行。语言 fMRI 方案涉及动词和句子生成。使用感兴趣区域（ROI）掩模对扫描进行定性解释和定量评估血氧水平依赖（BOLD）信号变化。我们计算了成功扫描的个体病例百分比，比较了左 TL 病变与右 TL 病变病例中的 2 个记忆任务激活掩模，并在有条件时比较了 fMRI 和 Wada 测试结果。具有可行 fMRI 和 Wada 测试的患者通常具有一致的结果。
在 72 例病例中，有 60 例（83%）年龄在 7.6-20.9 岁的患者成功完成了记忆 fMRI 任务，12 例（17%）患者失败。12 例不成功扫描中的 11 例是由于运动和/或无法完成任务，第十二例的成功是不确定的，因为存在正畸金属伪影。在成功的 60 例病例中，有 7 例病例的解剖结构扭曲，无法对定量分析使用预定的掩模。成功的 fMRI 记忆研究显示双侧内侧颞叶激活，并定量证明：（1）左颞叶（L-TL）病变病例的左激活（L-ACT）小于右激活（R-ACT），（2）右颞叶（R-TL）病变病例的右激活（R-ACT）无显著差异小于左激活（L-ACT），（3）L-TL 与 R-TL 病变病例的 L-ACT 和 R-ACT 激活较低。具有可行 fMRI 和 Wada 测试的患者通常具有一致的结果。
这项研究证明了一种 fMRI 记忆任务范式的证据，该范式可以在个体水平上产生可靠的激活，并且通常可以在临床相关的儿科患者中完成。这种自传体记忆范式显示在内侧 TL 结构中激活，并且与左侧相比，左侧 TL 病变病例的右侧 TL 病变病例显示与 TL 癫痫症相关的文献中一致的激活差异。需要进一步的研究来评估预后预测。
