Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
Neuromodulation Division, Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California.
Epilepsia. 2019 Aug;60(8):1721-1732. doi: 10.1111/epi.16284. Epub 2019 Jul 12.
To identify whether abnormal electroencephalography (EEG) connectivity is present before the onset of epileptic spasms (ES) in infants with tuberous sclerosis complex (TSC).
Scalp EEG recordings were collected prospectively in infants diagnosed with TSC in the first year of life. This study compared the earliest recorded EEG from infants prior to ES onset (n = 16) and from infants who did not develop ES (n = 28). Five minutes of stage II or quiet sleep was clipped and filtered into canonical EEG frequency bands. Mutual information values between each pair of EEG channels were compared directly and used as a weighted graph to calculate graph measures of global efficiency, characteristic path length, average clustering coefficient, and modularity.
At the group level, infants who later developed ES had increased EEG connectivity in sleep. They had higher mutual information values between most EEG channels in all frequency bands adjusted for age. Infants who later developed ES had higher global efficiency and average clustering coefficients, shorter characteristic path lengths, and lower modularity across most frequency bands adjusted for age. This suggests that infants who went on to develop ES had increased local and long-range EEG connectivity with less segregation of graph regions into distinct modules.
This study suggests that increased neural connectivity precedes clinical ES onset in a cohort of infants with TSC. Overconnectivity may reflect progressive pathologic network synchronization culminating in generalized ES. Further research is needed before scalp EEG connectivity measures can be used as a potential biomarker of ES risk and treatment response in pre-symptomatic infants with TSC.
确定在结节性硬化症（TSC）婴儿出现癫痫性痉挛（ES）之前，是否存在异常脑电图（EEG）连接。
在婴儿生命的第一年对诊断为 TSC 的婴儿进行前瞻性头皮 EEG 记录。本研究比较了 ES 发作前（n=16）和未发生 ES 的婴儿（n=28）最早记录的 EEG。截取并过滤 5 分钟的 II 期或安静睡眠，进入典型的 EEG 频带。直接比较每个 EEG 通道对之间的互信息值，并将其用作加权图，以计算全局效率、特征路径长度、平均聚类系数和模块度等图度量。
在组水平上，后来发生 ES 的婴儿在睡眠中有更高的 EEG 连接性。他们在所有调整年龄后的频带中，大多数 EEG 通道的互信息值更高。后来发生 ES 的婴儿具有更高的全局效率和平均聚类系数、更短的特征路径长度和更低的调整年龄后的大多数频带模块度。这表明，后来发生 ES 的婴儿具有增加的局部和远程 EEG 连接性，图区域的分区程度降低。
这项研究表明，在一组 TSC 婴儿中，增加的神经连接性先于临床 ES 发作。过度连接可能反映了渐进的病理网络同步，最终导致全身性 ES。在使用头皮 EEG 连接性测量作为 TSC 无症状婴儿 ES 风险和治疗反应的潜在生物标志物之前，还需要进一步的研究。
