Kortikale Dysplasie als epileptogener Fokus: Verminderte Bindung von I-Iomazenil bei unauffälliger ^99mTc-HMPAO SPECT

Zusammenfassung

In kortikalen Arealen, die einem epileptischen Fokus assoziiert sind, korreliert meist eine verminderte Benzodiazepin-Rezeptorbindung, darstellbar mit ¹²³I- Iomazeml, mit einer Minderung des regionalen zerebralen Blutflusses. Anhand eines Fallbeispiels mit ausgeprägter Minderung der ¹²³l-lomazenilbindung im epileptischen Fokus bei ungestörtem regionalen zerebralen Blutfluß wird illustriert und diskutiert, daß bei einer Minderanreicherung von ¹²³I-Iomazenil im epileptischen Fokus eine Alteration des GABAergen Systems anzunehmen ist.

Summary

In cortical areas associated with an epileptic focus, there is, in the majority of cases, a correlation between decreased benzodiazepine (Bz) receptor binding, detectable with ¹²³I-Iomazeml, and decreased blood flow. A patient with focal epilepsy due to a localized abnormality in cortical differentiation is presented who showed a marked focal decrease in Bz receptor binding and a normal ^99mTc-HMPAO SPECT. Based on this case the relation between blood flow and Bz receptor binding in epileptic foci is discussed.

Schlüsselwörter

Kortikale Dysplasie - Epilepsie - SPECT - Benzodiazepinrezeptoren

Key words

Cortical dysplasia - epilepsy - SPECT - benzodiazepine receptors

• Literatur

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