Normal magnetic resonance imaging and epilepsy surgery

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 …