Abstracts

RATIONALE: With the advent of new MRI techniques such as PW - (perfusion-weighted) and DW (diffusion-weighted)- sequences it is now possible to detect early regional tissue changes due to local energy failure This has been extensively demonstrated in acute ischemia. It was challenging to look for these findings in patients with acute onset of complex-partial seizures (CPS) both ictally and postictally. METHODS: We investigated 6 adult patients out of our comprehensive epilepsy program intra-or postictally within < 12 hours after CPS had occurred by means of MRI and MR-angiography (MRA). MRI was performed on a 1.5 Tesla scanner (Vision. Siemens) using standardized T-1, T2-, Proton density- plus echoplanar DW EP- and PW EP-sequences with sequential application of 3 separate sensitising gradients in orthogonal directions. RESULTS: We observed the following findings: 1) Reversible ADC reduction associated with regional hyperperfusion immediate after CPS or intraictally, 2) Reversible postictal vasodilatation on MRA, 3) Reversible regional T2-signal hyperintensity due to postictal edema lasting for up to 1 week, 4) Normal findings after short lasting seizure events. CONCLUSIONS: Our results strongly emphasize the value of new MRI-techniques for detecting reversible tissue changes immediately after or within local seizure activity demonstrating a wide range of features. These findings contribute to a further understanding of the pathophysiological processes in epilepsy and might imply the perspective of an additional non-invasive tool for localizing the epileptogenic zone in CPS patients.