%0 Journal Article %A C D Binnie %A R D Elwes %A C E Polkey %A A Volans %T Utility of stereoelectroencephalography in preoperative assessment of temporal lobe epilepsy. %D 1994 %R 10.1136/jnnp.57.1.58 %J Journal of Neurology, Neurosurgery & Psychiatry %P 58-65 %V 57 %N 1 %X Of 269 consecutive patients entered into a preoperative assessment programme for possible surgical treatment of epilepsy, 33 had intracranial recording (SEEG) with combined subdural and depth electrodes for the purpose of localising a suspected temporal site of seizure onset. The findings in these patients are analysed with particular reference to: 1) the criteria of selection for SEEG and their validity; 2) information on SEEG compared with that obtained by less invasive means, including foramen ovale telemetry; 3) information on the use of intracerebral electrodes compared with subdural placements; 4) possible predictors of failure of localisation by SEEG and of surgical outcome. It was concluded that SEEG had usefully contributed to the management of 69% of the patients in whom it was used, establishing a previously unidentified site of seizure onset in 33%, correcting an erroneous localisation in 15%, and establishing inoperability in 21% of patients. No predictors of failure of SEEG or of surgery emerged; thus there was no evidence of unnecessary use of this procedure. Five patients were found with incorrect lateralisation of seizure onset on foramen ovale recording (of a total of 192 foramen ovale telemetries). Localisation of the ictal onset zone either by the distribution of inter-ictal discharges or by the initial ictal changes at subdural electrodes was unreliable, confirming the need for ictal, depth recordings. %U https://jnnp.bmj.com/content/jnnp/57/1/58.full.pdf