Two broad principles should be followed when assessing patients for epilepsy surgery. Firstly, the evaluation requires a multidisciplinary team and secondly, patients should be offered surgery whenever possible on the basis of congruence of non-invasive tests. One of the difficulties that arises, however, is that patients with a definite history of intractable focal epilepsy may have either non-localising or non-congruent investigations. If this occurs then such discrepancies should be resolved by intracranial EEG.

Scott et al (this volume, pp 69-71) report their experience with an important group in which high resolution MRI was normal. This occurred in 20% of their patients but may be much more common in non-surgical series. Out of their 36 patients evaluated with scalp telemetry, 13 had a non-localising electroclinical syndrome. In such cases there would be widespread agreement in all epilepsy surgery programmes that further presurgical evaluation should be abandoned. Their arguments that intracranial EEG should not . . . [Full text of this article]