Article

Diffusion-weighted magnetic resonance imaging in patients with partial status epilepticus

Department of Neurological Sciences, University of Rome La Sapienza, Rome, Italy.
Epilepsia (Impact Factor: 4.58). 02/2009; 50 Suppl 1(s1):45-52. DOI: 10.1111/j.1528-1167.2008.01970.x
Source: PubMed

ABSTRACT Diffusion-weighted magnetic resonance imaging (DWI) is used to detect changes in the distribution of water molecules in regions affected by various pathologies. Like other conditions, ictal epileptic activity, such as status epilepticus (SE), can cause regional vasogenic/cytotoxic edema that reflects hemodynamic and metabolic changes. This study describes the electroclinical and neuroimaging findings in 10 patients with partial SE whose DWI evaluation disclosed periictal changes related to sustained epileptic activity.
In this retrospective study we selected 10 patients with partial SE of different etiologies (six acute symptomatic SE; four with previous epilepsy and concomitant precipitating factors) who underwent video-EEG (electroencephalography) monitoring and a DWI study during the periictal phase. We analyzed ictal electroclinical features and DWI changes in the acute phase and during the follow-up period.
DWI images revealed significant signal alterations in different brain regions depending on the location of ictal activity. DWI changes were highly concordant with the electroclinical findings in all 10 patients. As the SE resolved and the clinical conditions improved, DWI follow-up showed that the signal alterations gradually disappeared, thereby documenting their close relationship with ictal activity.
This study confirms the usefulness of DWI imaging in clinical practice for a more accurate definition of the hemodynamic/metabolic changes occurring during sustained epileptic activity.

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