Long-Term Seizure Outcome in Patients Undergoing Resection of Lesions Detected by Magnetic Resonance Imaging

Abstract

The long-term efficacy of resective surgery was investigated in patients with lesions detected by magnetic resonance (MR) imaging. Thirty of 47 patients who had undergone lesionectomy between 1987-2001 were followed up by questionnaire. Patients with extratemporal resections outnumbered those with temporal lobe resections. The mean follow-up period was 12.4 ± 3.7 years. Outcomes were graded according to Engel's criteria, and an arbitrary seizure outcome score was given for quantitative assessment. The mean seizure outcome scores were significantly lower in the early childhood (less than 3 years) onset group than in the late childhood (3 to 15 years) onset group, and significantly lower in the extratemporal resection of the cortical dysplasia group than in the temporal resection and the extratemporal resection of non-cortical dysplasia groups. This study indicated that lesionectomy based on MR imaging findings in patients with intractable epilepsy achieved effective long-term seizure control, and the outcome was related mainly to the pathology of the epileptogenic lesions and the temporal or extratemporal location.

Clinical, functional, and neurophysiologic assessment of dysplastic cortical networks: Implications for cortical functioning and surgical management

“…Apart from this subgroup, the success rate for remaining patients, as evidenced by complete abolition of seizures, was considerably diminished. These low rates of seizure‐freedom stood in stark contrast to surgical outcome for seizures caused by other pathologic substrates including hippocampal sclerosis, porencephaly, vascular malformations, and tumors (Zentner et al., 1997; Jeong et al., 1999; Moritake et al., 2008).…”

Postoperative Quality of Life Outcome and Employment in Patients Undergoing Resection of Epileptogenic Lesions Detected by Magnetic Resonance Imaging

“…13) Patients free of seizures and those with at least 90% reduction in seizure frequency reported significant improvements in HRQOL at 24 months. 15) Our previous study 17) on the long-term seizure outcome in the same subjects indicated that lesionectomy based on MR imaging in patients of intractable epilepsy was effective for long-term seizure control and the postoperative seizure outcome was related mainly to the pathology of the epileptogenic lesions, with excellent seizure outcome in patients in the Non-CD exT group and poor in those in the CD exT group. The present study of long-term QOL outcome showed compatible findings.…”

“…The histological diagnoses of the epileptogenic lesions were shown previously. 17) The most prominent findings were neuronal loss and gliosis, which was associated with cerebral scarring or porencephaly after head injury, infection, or vascular malformation, or was of unknown origin. Mesial temporal sclerosis was found in 6 patients, and cortical dysplasia and cryptic angioma in 3 patients each.…”

“…To assess the surgical results quantitatively with regard to postoperative reduction in seizure frequency, a score for Engel's grades was assigned as follows: Class I, 5 points; Class II, 3 points; Class III, 1 point; and Class IV, 0 points. 17) Postoperative QOL in terms of disability in daily living at the longest follow up was divided into four grades as follows: normal range (work or study possible), slightly disturbed (independent daily living possible), moderately disturbed (partial care required in daily living), and severely disturbed (care required for all activities of daily living). An arbitrary point system was assigned as follows: normal range, 5 points; slightly disturbed, 4 points; moderately disturbed, 3 points; and severely disturbed, 1 point.…”

“…16) Our previous study of postoperative long-term seizure outcome, 5 years or more after epilepsy surgery, in patients undergoing lesionectomy under this protocol found that the outcome was related mainly to the pathology of epileptogenic lesions and whether the lesion site was temporal or extratemporal. 17) The present study evaluated the long-term efficacy of lesionectomy on improvement of quality of life (QOL) in the same series, which includes more extratemporal than temporal lobe resections, and also investigated the preoperative factors associated with long-term QOL improvement.…”