Reduction of EEG Myogenic Artifact with Botulinum Toxin during Video‐EEG Monitoring

Abstract

Summary:Purpose: To determine whether EEG myogenic artifact during video-EEG monitoring (VEM) is reduced with targeted scalp botulinum toxin (BTX-A) injections.Methods: Twelve consecutive patients scheduled for presurgical VEM were treated 2-3 weeks before admission with subcutaneous BTX-A injections at specific EEG electrode locations. On the basis of clinical data available before VEM, four subjects were treated unilaterally (group 1) and eight bilaterally (group 2). BTX-A efficacy was assessed quantitatively in group 1 subjects by comparing high-frequency (20-100 Hz) power at homologous "treated" and "untreated" electrodes during voluntary forceful jaw closure. The clinical impact of BTX-A treatment was assessed by determining whether ≥5 of the first 10 s of each ictal recording was obscured by muscle artifact, and whether residual myogenic artifact on BTX-A-"treated" electrodes rendered these ictal EEG segments impossible to interpret.Results: BTX-A treatment reduced high-frequency power by a mean of 53% at electrodes T3/T4 and 52% at electrodes F7/F8. None of 49 ictal EEGs had ≥5 of the first 10 s obscured by myogenic artifact, and all of these ictal epochs were interpretable. Adverse events were limited to two subjects who complained of transient difficulty chewing tough foods.Conclusions: Scalp-muscle BTX-A treatment before VEM significantly reduces myogenic artifact in subsequent EEG recordings, including ictal EEG. The clinical utility of this technique for improved or more-rapid seizure localization will be determined only by large, blinded, prospective trials.

Neurologic uses of botulinum neurotoxin type A

“…BoNT-A for perioperative pain (Davies et al 2003), treatment for amputation stump-related and phantom-limb pain (Kern et al 2003), plantar fasciitis (Babcock et al 2005), carpal tunnel related-pain (Tsai et al 2006), and even refractory restless-legs syndrome (Rotenburg et al 2006) have been reported. Botulinum toxins may have a role in electrodiagnosis, using BoNT-A pretreatment to reduce electromyographic frontotemporal artifact in electroencephalographic localization of aberrant cerebral discharges (Grant and Hermanowicz 2007). Lastly, direct infusion of botulinum toxin A has been shown in vivo to inhibit enzymes responsible for hippocampal cell death following induced seizures in rats (Manno et al 2007).…”

Justinus Kerners therapeutische Visionen “reloaded”

“…Auch auf der Intensivstation lässt sich massives Beißen auf den Tubus oder auf eingeführte Endoskope durch eine Masseterinjektion beheben. Eine ungewöhnliche Vermeidung von EEG-Muskelartefakten ist durch eine botulinumtoxininduzierte Lähmung der verursachenden Muskulatur möglich (7,14).…”

Botulinum toxin assessment, intervention and aftercare for paediatric and adult niche indications including pain: international consensus statement

“…Similarly, BoNT-A has been used prior to selective peripheral neurotomy in children with spasticity [39]. In adults with epilepsy whose scalp EEG localization of seizures is limited by EMG artefact from contraction of cranial muscles, BoNT-A has been used to diminish artefact and allow seizure localization, a requirement for considering further epilepsy surgery [40,41]. Only in the study by Grant et al [41] was a minor adverse event noted (two patients reported transient difficulty chewing) ( Table 3).…”

“…Only in the study by Grant et al. [41] was a minor adverse event noted (two patients reported transient difficulty chewing) (Table 3).…”