Korean J Neurotrauma.  2013 Oct;9(2):96-100. 10.13004/kjnt.2013.9.2.96.

Clinical Efficacy of Acute Monitoring Cortical Activity Using Subdural Strip Electrode after Decompressive Craniectomy

• Lee JH
• Hur JS
• Kim BJ
• Moon HJ
• Kim JH
• Kim JH
• Kwon TH
• Park YK
• Chung HS

• KMID: 2156108
• DOI: http://doi.org/10.13004/kjnt.2013.9.2.96

Abstract

OBJECTIVE
Decompressive craniectomy is widely used in cases of uncontrolled intracranial hypertension, including traumatic brain injury or acute stroke. Physiological monitorings, such as intracranial pressure or electroenecephalography (EEG) are critical for patients in the acute phase. We retrospectively reviewed our experience of continuous electrocorticography (ECoG) monitoring by subdural strip electrode in patients who performed decompressive craniectomy and assessed its clinical efficacy.
METHODS
Patients who underwent decompressive craniectomy because of severe intracranial hypertension were included. 4 Channel strip electrodes were inserted on the frontal cortex before closure. 24-hour continuous monitoring of ECoG was done to identify abnormal electrical activity. The level of consciousness was assessed according to Glasgow Coma Scale (GCS). In patients with malignant intracranial hypertension, barbiturate coma therapy was considered.
RESULTS
Fifteen patients (9 men and 6 women) were included and the mean age was 55.7 years (from 17 to 80). The initial mean GCS score was 7.9 (from 3 to 14). In six out of fifteen patients, abnormal spike activities were identified, and one of these six patients was diagnosed as nonconvulsive status epilepticus (NCSE). Cortical spreading depression (CSD) was suspected in five. Three patients underwent barbiturate coma therapy and ECoG monitoring of these patients showed typical burst suppression pattern, which was used for indicator of therapeutic level. The mean duration of strip electrode and ECoG monitoring was 3.5 days, and there was no complication.
CONCLUSION
Continuous ECoG monitoring using subdural strip electrode was useful to detect abnormal brain activity in the acute period after decompressive craniectomy.

Keyword

Subdural electrode; Electrocorticography; Traumatic brain injury; Status epilepticus; Cortical spreading depression; Burst suppression

MeSH Terms

Barbiturates
Brain
Brain Injuries
Coma
Consciousness
Cortical Spreading Depression
Decompressive Craniectomy*
Electrodes*
Glasgow Coma Scale
Humans
Intracranial Hypertension
Intracranial Pressure
Male
Retrospective Studies
Status Epilepticus
Stroke
Barbiturates

Figure

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  FIGURE 1. A: 4-channel strip electrode. The width of electrode is 5 mm and the gap between electrodes is 10 mm. B: Skull X-ray (lateral view) after decompressive craniectomy. Subdural strip electrode (arrow) was inserted.

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  FIGURE 2. A: Nonconvulsive status epilepticus in patient with acute subdural hematoma (Patient No.10). Abnormal fast spiking activities are shown in all channels when patient showed ictal nystagmus and decrease of consciousness. B: Cortical spreading depression in patient with subarachnoid hemorrhage (Patient No.2). Time-compressed tracing shows depressed ECoG activity (arrowhead), about 60% reduction of amplitude, evolved over 30 seconds and lasted for about 5 minutes in upper row. This is followed by a similar change in lower row about 4 minutes later. The distance of each contact of strip electrode is 10 mm, so the propagation rate is about 2 mm/min. C: Burst-suppression pattern of ECoG activity in patient with barbiturate coma therapy (Patient No. 1). Bursting activities (arrows) are shown in all channels after several seconds period of suppressed ECoG. ECoG: electrocorticogram.

Reference

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