Acta Neurol Scand 1999: 99: 8-15 Printed in UK zyxwvutsrqponm - all rights reserved Copyright zyxw I Munksgaard 1999 ACTA zyxw NEUROLOGICA SCANDINAVICA ISSN zyxw 0001-6314 Surgical treatment of epilepsy - clinical, radiological and histopathological findings in 139 children and adults Eriksson S, Malmgren K, Rydenhag B, Jonsson L, Uvebrant P, Nordborg C. Surgical treatment of epilepsy - clinical, radiological and histopathological findings in 139 children and adults. Acta Neurol Scand 1999: 99: 8-15. C Munksgaard 1999. The present study relates clinical and radiological data to histopathological diagnoses in the first 139 patients (children and adults) in the Goteborg Epilepsy Surgery series. Temporal lobe resections were most common (54.0%) followed by frontal lobe (18.0%) and multilobar resections (11.5y0). All histopathological specimens were re-evaluated in connection with this study. Parenchymal malformations and atrophic-gliotic lesions were the most common histopathological findings. Microdysgenesis was more common than major malformations (24.5% versus 11.5%). When the MRI scans were blindly re-evaluated the MRI findings correlated with histopathological diagnosis in all of the vascular malformations, in 77.8% of the tumours, in 76.5% of the cases with hippocampal sclerosis but only in 28.6% of the major cortical development malformations. Hemispherectomies carried the best seizure outcome prognosis followed by temporal lobe resections (75.0% versus 57.3% seizure free 2 years after surgery). Vascular malformations carried the best, and microdysgenesis the 1 worst prognosis (76.9% versus 39.4% seizure free). Epilepsy surgery has undergone a rapid develop- ment in the last decades with a world-wide increase in the number of operating centres (1). This is true also for Sweden where around 80 children and adults are operated on yearly in a population of 8.8 million (2). The same period has also seen a tremendous development in neuroimaging tech- niques (3-6), which has led to an increased interest in the relation between structural lesions and the development of epilepsy (7-11). However, there is still a large proportion of patients in whom no structural correlates can be found despite high quality MRI (12, 13), and in these cases further histopathological analyses using modern tech- niques are of special importance to increase our knowledge of the etiology of surgically treated epilepsy. The most common histopathological findings in specimens from patients operated on because of intractable epilepsy are tumours, hippocampal sclerosis, vascular and parenchymal malformations (11, 14-19). Recently, improvement of neuroima- zyxwv S. Eriksson', K. Malmgren', B. Rydenhag', 1. Jonsson3, P. Uvebrant4, C. Nordborg5 Institute of Clinical Neuroscience, Depts of 'Neurology and 'Neurosurgery, Institute of Selected Clinical Sciences. Depts of 3Radiology and 4Pediatrics Institute of Laboratory Medicine. Dept of 'Pathology, Sahlgrenska University Hospital. Goteborg, Sweden Key words: epilepsy surgery; magnetic resonance imaging. histopathology. microdysgenesis; outcome Sofia Eriksson. Institute of Clinical Neuroscience. Dept of Neurology, Sahlgrenska University Hospital. S-413. 45 Goteborg. Sweden 1 Accepted for publication September 9, 1998 ging techniques has led to an increased detection of parenchymal malformations preoperatively (10,13, 20). The major parenchymal malformations are usually classified according to distinct macroscopi- cal patterns (21,22) while minor malformations are classified according to specific microscopical fea- tures (23-27). The epilepsy surgery programme in Goteborg started in 1987. Sahlgrenska University Hospital is a tertiary referral centre for the region of western Sweden comprising 1.8 million inhabitants. Patients with medically refractory epilepsy are referred to the regional epilepsy centre for consideration and epilepsy surgery is performed not only when it can be hoped to be curative, but also in many cases as a palliative procedure. In the present study the first 139 consecutive patients operated on from 1987 to 1995 have been analysed with respect to clinical features, neuroradiological and histopathological findings as well as outcome. The series comprises children and adults (ranging in age from 0.9 to 62 years at the time of operation) subjected to a wide 8