PDF(Pubmed)
Abstract：
OBJECTIVE: Individuals with drug-resistant epilepsy may benefit from epilepsy surgery. In nonlesional cases, where no epileptogenic lesion can be detected on structural magnetic resonance imaging, multimodal neuroimaging studies are required. Breath-hold-triggered BOLD fMRI (bh-fMRI) was developed to measure cerebrovascular reactivity in stroke or angiopathy and highlights regional network dysfunction by visualizing focal impaired flow increase after vasodilatory stimulus. This regional dysfunction may correlate with the epileptogenic zone. In this prospective single-center single-blind pilot study, we aimed to establish the feasibility and safety of bh-fMRI in individuals with drug-resistant non-lesional focal epilepsy undergoing presurgical evaluation.
METHODS: In this prospective study, 10 consecutive individuals undergoing presurgical evaluation for drug-resistant focal epilepsy were recruited after case review at a multidisciplinary patient management conference. Electroclinical findings and results of other neuroimaging were used to establish the epileptogenic zone hypothesis. To calculate significant differences in cerebrovascular reactivity in comparison to the normal population, bh-fMRIs of 16 healthy volunteers were analyzed. The relative flow change of each volume of interest (VOI) of the atlas was then calculated compared to the flow change of the whole brain resulting in an atlas of normal cerebral reactivity. Consequently, the mean flow change of every VOI of each patient was tested against the healthy volunteers group. Areas with significant impairment of cerebrovascular reactivity had decreased flow change and were compared to the epileptogenic zone localization hypothesis in a single-blind design.
RESULTS: Acquisition of bh-fMRI was feasible in 9/10 cases, with one patient excluded due to noncompliance with breathing maneuvers. No adverse events were observed, and breath-hold for intermittent hypercapnia was well tolerated. On blinded review, we observed full or partial concordance of the local network dysfunction seen on bh-fMRI with the electroclinical hypothesis in 6/9 cases, including cases with extratemporal lobe epilepsy and those with nonlocalizing 18F-fluorodeoxyglucose positron emission tomography (FDG-PET).
CONCLUSIONS: This represents the first report of bh-fMRI in individuals with epilepsy undergoing presurgical evaluation. We found bh-fMRI to be feasible and safe, with a promising agreement to electroclinical findings. Thus, bh-fMRI may represent a potential modality in the presurgical evaluation of epilepsy. Further studies are needed to establish clinical utility.
METHODS: In this prospective study, 10 consecutive individuals undergoing presurgical evaluation for drug-resistant focal epilepsy were recruited after case review at a multidisciplinary patient management conference. Electroclinical findings and results of other neuroimaging were used to establish the epileptogenic zone hypothesis. To calculate significant differences in cerebrovascular reactivity in comparison to the normal population, bh-fMRIs of 16 healthy volunteers were analyzed. The relative flow change of each volume of interest (VOI) of the atlas was then calculated compared to the flow change of the whole brain resulting in an atlas of normal cerebral reactivity. Consequently, the mean flow change of every VOI of each patient was tested against the healthy volunteers group. Areas with significant impairment of cerebrovascular reactivity had decreased flow change and were compared to the epileptogenic zone localization hypothesis in a single-blind design.
RESULTS: Acquisition of bh-fMRI was feasible in 9/10 cases, with one patient excluded due to noncompliance with breathing maneuvers. No adverse events were observed, and breath-hold for intermittent hypercapnia was well tolerated. On blinded review, we observed full or partial concordance of the local network dysfunction seen on bh-fMRI with the electroclinical hypothesis in 6/9 cases, including cases with extratemporal lobe epilepsy and those with nonlocalizing 18F-fluorodeoxyglucose positron emission tomography (FDG-PET).
CONCLUSIONS: This represents the first report of bh-fMRI in individuals with epilepsy undergoing presurgical evaluation. We found bh-fMRI to be feasible and safe, with a promising agreement to electroclinical findings. Thus, bh-fMRI may represent a potential modality in the presurgical evaluation of epilepsy. Further studies are needed to establish clinical utility.
摘要：
目的：耐药癫痫患者可从癫痫手术中获益。在非病变病例中，在结构磁共振成像中无法检测到癫痫灶，需要进行多模态神经影像学研究。开发了屏气触发的BOLDfMRI（bh-fMRI）来测量中风或血管病变中的脑血管反应性，并通过可视化血管扩张刺激后的局灶性血流增加来突出区域网络功能障碍。这种区域性功能障碍可能与癫痫发生区有关。在这项前瞻性单中心单盲试点研究中，我们的目的是在接受术前评估的耐药非病灶局灶性癫痫患者中建立bh-fMRI的可行性和安全性.
方法：在这项前瞻性研究中，在多学科患者管理会议上进行病例审查后，招募了10名接受耐药性局灶性癫痫术前评估的连续个体。使用电临床发现和其他神经影像学的结果来建立癫痫发生区假设。为了计算与正常人群相比脑血管反应性的显着差异，对16名健康志愿者的bh-fMRI进行分析。然后与整个大脑的流量变化相比，计算图谱的每个感兴趣体积（VOI）的相对流量变化，从而产生正常大脑反应性的图谱。因此,针对健康志愿者组测试了每位患者每次VOI的平均流量变化。脑血管反应性显着受损的区域的血流变化减少，并在单盲设计中与癫痫区定位假说进行了比较。
结果：在9/10例中，获得bh-fMRI是可行的，一名患者因不遵守呼吸操作而被排除。没有观察到不良事件，间歇性高碳酸血症的屏气耐受性良好。在盲目性审查中，我们在6/9例中观察到在bh-fMRI上看到的局部网络功能障碍与电临床假设完全或部分一致，包括颞叶外叶癫痫和非定位18F-氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）的病例。
结论：这是bh-fMRI在接受术前评估的癫痫患者中的首次报告。我们发现bh-fMRI是可行和安全的,与电临床研究结果达成了有希望的协议。因此，bh-fMRI可能是癫痫术前评估的一种潜在方式。需要进一步的研究来建立临床效用。
方法：在这项前瞻性研究中，在多学科患者管理会议上进行病例审查后，招募了10名接受耐药性局灶性癫痫术前评估的连续个体。使用电临床发现和其他神经影像学的结果来建立癫痫发生区假设。为了计算与正常人群相比脑血管反应性的显着差异，对16名健康志愿者的bh-fMRI进行分析。然后与整个大脑的流量变化相比，计算图谱的每个感兴趣体积（VOI）的相对流量变化，从而产生正常大脑反应性的图谱。因此,针对健康志愿者组测试了每位患者每次VOI的平均流量变化。脑血管反应性显着受损的区域的血流变化减少，并在单盲设计中与癫痫区定位假说进行了比较。
结果：在9/10例中，获得bh-fMRI是可行的，一名患者因不遵守呼吸操作而被排除。没有观察到不良事件，间歇性高碳酸血症的屏气耐受性良好。在盲目性审查中，我们在6/9例中观察到在bh-fMRI上看到的局部网络功能障碍与电临床假设完全或部分一致，包括颞叶外叶癫痫和非定位18F-氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）的病例。
结论：这是bh-fMRI在接受术前评估的癫痫患者中的首次报告。我们发现bh-fMRI是可行和安全的,与电临床研究结果达成了有希望的协议。因此，bh-fMRI可能是癫痫术前评估的一种潜在方式。需要进一步的研究来建立临床效用。
