Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, California, USA.
Department of Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland.
Epilepsia. 2021 Apr;62(4):947-959. doi: 10.1111/epi.16841. Epub 2021 Feb 26.
Intracranial electroencephalography (ICEEG) recordings are performed for seizure localization in medically refractory epilepsy. Signal quantifications such as frequency power can be projected as heatmaps on personalized three-dimensional (3D) reconstructed cortical surfaces to distill these complex recordings into intuitive cinematic visualizations. However, simultaneously reconciling deep recording locations and reliably tracking evolving ictal patterns remain significant challenges.
We fused oblique magnetic resonance imaging (MRI) slices along depth probe trajectories with cortical surface reconstructions and projected dynamic heatmaps using a simple mathematical metric of epileptiform activity (line-length). This omni-planar and surface casting of epileptiform activity approach (OPSCEA) thus illustrated seizure onset and spread among both deep and superficial locations simultaneously with minimal need for signal processing supervision. We utilized the approach on 41 patients at our center implanted with grid, strip, and/or depth electrodes for localizing medically refractory seizures. Peri-ictal data were converted into OPSCEA videos with multiple 3D brain views illustrating all electrode locations. Five people of varying expertise in epilepsy (medical student through epilepsy attending level) attempted to localize the seizure-onset zones.
We retrospectively compared this approach with the original ICEEG study reports for validation. Accuracy ranged from 73.2% to 97.6% for complete or overlapping onset lobe(s), respectively, and ~56.1% to 95.1% for the specific focus (or foci). Higher answer certainty for a given case predicted better accuracy, and scorers had similar accuracy across different training levels.
In an era of increasing stereo-EEG use, cinematic visualizations fusing omni-planar and surface functional projections appear to provide a useful adjunct for interpreting complex intracranial recordings and subsequent surgery planning.
颅内脑电图 (ICEEG) 记录用于定位药物难治性癫痫的发作部位。可以将信号量化（如频率功率）投影为个性化三维 (3D) 重建皮质表面的热图，从而将这些复杂的记录简化为直观的电影可视化效果。然而，同时协调深部记录位置和可靠地跟踪不断发展的发作模式仍然是重大挑战。
我们沿着深度探测轨迹融合斜磁共振成像 (MRI) 切片与皮质表面重建，并使用癫痫活动的简单数学度量（线长）投影动态热图。这种全方位和表面投射的癫痫活动方法 (OPSCEA) 因此同时展示了深部和浅部位置的发作起始和传播，而对信号处理监督的需求最小。我们在我们中心的 41 名接受网格、条带和/或深部电极植入以定位药物难治性癫痫发作的患者中使用了该方法。将发作期数据转换为 OPSCEA 视频，其中包含多个 3D 脑视图，显示所有电极位置。五名具有不同癫痫专业知识（从医学生到癫痫主治医生）的人员试图定位发作起始区。
我们回顾性地将该方法与原始 ICEEG 研究报告进行了比较以进行验证。对于完整或重叠的起始叶，准确性范围分别为 73.2%至 97.6%，对于特定焦点（或焦点），准确性范围为 56.1%至 95.1%。对于给定病例的更高答案确定性预测了更好的准确性，评分者在不同的培训水平下具有相似的准确性。
在立体脑电图使用日益增加的时代，融合全方位和表面功能投影的电影可视化似乎为解释复杂的颅内记录和随后的手术计划提供了有用的辅助手段。
