Artikel
Spreading depolarizations in perilesional cortex of human ischemic stroke
'Spreading depolarizations' im periläsionalen Cortex von Patienten nach zerebrovaskulärem Insult
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Veröffentlicht: | 11. April 2007 |
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Objective: Cortical spreading depression (CSD) and peri-infarct depolarisation (PID) are examples of spreading depolarisations (SD) in experimental models of stroke. SD are thought to cause infarct expansion and secondary neuronal damage. In human victims of stroke SD have never been shown, while in patients with subarachnoid hemorrhage and traumatic brain injury SD have been reported recently. In this study we investigated the occurrence of SD in perilesional cortex of patients following surgical decompression for malignant middle cerebral artery (MCA) infarction.
Methods: Twelve patients were recruited by centers of the Co-operative Study on Brain Injury Depolarisations (COSBID) after approval by the local ethics committees. Following decompressive hemicraniectomy for malignant MCA infarction, subdural electrode strips with 6 linear contacts (Wyler, 5/10 mm; Ad-Tech Medical Instrument Corp., Racine, WI) were placed adjacent to infarcted cortex in a centrifugal orientation. Postoperatively, perilesional localization of electrode strips was confirmed by computer tomography. Monitoring of the electrocorticogram (EcoG) was performed for up to 120 h following infarction.
Results: In all patients with perilesional location of EcoG recordings (n=9) spontaneously occurring SD were observed. In total, 147 episodes were recorded. Of these, 98 episodes were classified as CSD, characterized by slow potential changes spreading between channels with a gradually developing depression of ECoG activity and subsequent recovery. Forty-nine episodes were defined as PID with stereotyped spreading slow potential changes on channels with locally depressed spontaneous ECoG activity. In patients with recordings overlying infarcted tissue (n=3) no SD were observed.
Conclusions: In perilesional cortex of patients with malignant MCA infarction the incidence of SD was surprisingly high. Their absence in recordings of infarcted tissue suggests that SD are associated with the ongoing pathophysiology of human stroke. Future studies will have to show the potential value of SD for diagnostics and targeted therapy of stroke progression.