Department of Neurology, Division of Epilepsy, University of California, San Francisco, San Francisco, CA, USA.
Division of Pediatric Neurology, Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
Clin Neurophysiol. 2020 Jul;131(7):1433-1443. doi: 10.1016/j.clinph.2020.03.025. Epub 2020 Apr 10.
Intracranial high frequency oscillation (HFO) occurrence rate (OR) and slow wave activity (SWA) coupling are potential markers of epileptogenicity in epileptic spasms (ES). Scalp ripple (R) detection and SWA coupling have been described in ES; however, the feasibility of scalp fast ripple (FR) detection and measurement of scalp FR coupling to SWA is not known. We evaluated interictal scalp R and FR OR and SWA coupling in pre-treatment EEG in children with short-term treatment-refractory ES compared to short-term treatment non-refractory ES.
We retrospectively identified children with ES and identified HFOs using a semi-automated HFO detector on pre-treatment scalp EEG during sleep. We evaluated HFO OR and event-triggered modulation index (MI) to quantify R (100-250 Hz) and FR (250-600 Hz) coupling strength with different SWA passbands (0.5-1, 1-2, 2-3, 3-4, and 4-8 Hz). We used HFO phasor transform and circular statistics to evaluate phase coupling angle distributions.
We identified 15 children with ES with pre-treatment EEG recorded at 2000 Hz. Thirteen out of 15 patients had HFOs and were included for analysis. There were six treatment responders and seven nonresponders three months after treatment initiation. Responders and nonresponders were similar in age (6.1 vs 7.2 mo), ES diagnosis duration (0.7 vs 2.6 mo), and HFO OR (R: 1.07 vs 2.30/min, FR: 0.43 vs 1.96/min). No differences between responders and nonresponders were seen in HFO MI at different SWA. Coupling of R and FR to 2-3 Hz SWA demonstrated increased incidence rate ratio in nonresponders relative to responders at distinct phase coupling angle distributions.
This study demonstrates the feasibility of interictal scalp R and FR detection and quantification of scalp R and FR coupling to SWA in ES.
HFO phase coupling with SWA may be useful as a marker of potential treatment refractoriness in patients with ES.
颅内高频振荡（HFO）发生率（OR）和慢波活动（SWA）耦合是癫痫性痉挛（ES）致痫性的潜在标志物。头皮棘波（R）检测和 SWA 耦合已在 ES 中描述；然而，头皮快棘波（FR）检测的可行性和 SWA 到 FR 的耦合测量尚不清楚。我们评估了短期治疗耐药性 ES 与短期治疗非耐药性 ES 患儿治疗前脑电图的发作间期头皮 R 和 FR OR 以及 SWA 耦合。
我们回顾性地确定了 ES 患儿，并使用睡眠期间头皮脑电图的半自动化 HFO 探测器检测 HFO。我们评估了 HFO OR 和事件触发调制指数（MI），以量化不同 SWA 带通（0.5-1、1-2、2-3、3-4 和 4-8 Hz）的 R（100-250 Hz）和 FR（250-600 Hz）耦合强度。我们使用 HFO 位相变换和圆形统计来评估位相耦合角分布。
我们在 2000 Hz 下记录了 15 名 ES 患儿的治疗前脑电图，并识别出 13 名患儿有 HFO 并进行了分析。治疗开始后 3 个月，有 6 名患儿为治疗反应者，7 名患儿为无反应者。反应者和无反应者在年龄（6.1 个月与 7.2 个月）、ES 诊断持续时间（0.7 个月与 2.6 个月）和 HFO OR（R：1.07 次/分钟与 2.30 次/分钟，FR：0.43 次/分钟与 1.96 次/分钟）方面无差异。在不同的 SWA 下，反应者和无反应者的 HFO MI 之间没有差异。R 和 FR 与 2-3 Hz SWA 的耦合在不同的位相耦合角分布中显示，无反应者的发生率比反应者高。
本研究表明，在 ES 中，发作间期头皮 R 和 FR 的检测和定量以及头皮 R 和 FR 与 SWA 的耦合是可行的。
HFO 与 SWA 的位相耦合可能是 ES 患者潜在治疗耐药性的有用标志物。
