Long-term outcome of extratemporal resection in posttraumatic epilepsy

ArticleinNeurosurgical FOCUS 32(3):E10 · March 2012with15 Reads
DOI: 10.3171/2012.1.FOCUS11329 · Source: PubMed
Abstract
Posttraumatic epilepsy (PTE) is a common cause of medically intractable epilepsy. While much of PTE is extratemporal, little is known about factors associated with good outcomes in extratemporal resections in medically intractable PTE. The authors investigated and characterized the long-term outcome and patient factors associated with outcome in this population. A single-institution retrospective query of all epilepsy surgeries at Regional Epilepsy Center at the University of Washington was performed for a 17-year time span with search terms indicative of trauma or brain injury. The query was limited to adult patients who underwent an extratemporal resection (with or without temporal lobectomy), in whom no other cause of epilepsy could be identified, and for whom minimum 1-year follow-up data were available. Surgical outcomes (in terms of seizure reduction) and clinical data were analyzed and compared. Twenty-one patients met inclusion and exclusion criteria. In long-term follow-up 6 patients (28%) were seizure-free and an additional 6 (28%) had a good outcome of 2 or fewer seizures per year. Another 5 patients (24%) experienced a reduction in seizures, while only 4 (19%) did not attain significant benefit. The presence of focal encephalomalacia on imaging was associated with good or excellent outcomes in 83%. In 8 patients with the combination of encephalomalacia and invasive intracranial EEG, 5 (62.5%) were found to be seizure free. Normal MRI examinations preoperatively were associated with worse outcomes, particularly when combined with multifocal or poorly localized EEG findings. Two patients suffered complications but none were life threatening or disabling. Many patients with extratemporal PTE can achieve good to excellent seizure control with epilepsy surgery. The risks of complications are acceptably low. Patients with focal encephalomalacia on MRI generally do well. Excellent outcomes can be achieved when extratemporal resection is guided by intracranial EEG electrodes defining the extent of resection.
    • Posttraumatic epilepsy can be notoriously difficult to treat compared to other types of epilepsy with focal onset, for example, poststroke epilepsy (Hakimian et al., 2012). However, epilepsy after TBI may be preventable because posttraumatic seizures may follow the injury only after a number of years (Annegers et al., 1998; Christensen et al., 2009; Ferguson et al., 2010).
    [Show abstract] [Hide abstract] ABSTRACT: Traumatic brain injury (TBI) is a potentially preventable cause of epilepsy. Increasing incidence among army personnel and the high incidence among children and young people raise concern. This article presents a review of selected studies dealing with the risks of TBI and the risk of posttraumatic epilepsy in humans. The incidence of persons admitted to hospital with TBI has decreased in developed countries in recent years. However, there is little change in TBI-associated deaths, and the decrease in hospitalization may merely reflect that more people with head injury are cared for on an outpatient basis. It is clear that epilepsy is a frequent consequence of brain injury, even many years after the injury. However, several well-controlled studies have been unable to identify therapies that prevent the development of epilepsy after TBI. Posttraumatic epilepsy has significant implications for the affected individuals, family, and society. Despite several interventions used to prevent posttraumatic epilepsy, the only proven "intervention" to date is to prevent TBI from occurring.
    Full-text · Article · Sep 2012
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    Article · Oct 2014
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    Article · Feb 2015
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