¹²³J-Iomazenil- und ^99mTc-HMPAO in der Diagnostik fokaler Epilepsien: Vergleich von unbehandelten und behandelten Patienten

Zusammenfassung

Die Daten von insgesamt 20 Patienten mit fokalen Epilepsien (beh.: 7; unbeh.: 13) wurden mit dem Ziel ausgewertet, Unterschiede in der Bindung der Radiotracer HMPAO und IM घ zwischen behandelten und unbehandelten Patienten herauszufinden. CT und MIRT zeigten keine pathologischen Befunde. Bei allen Patienten wurden mittels SPECT die Gesamthirnaktivität und durch Anwendung der ROI-Technik regionale Impulsdichten (Rl) bestimmt und der spezifische und unspezifische Anteil der Rl des BZ-Antagonisten für jede Region berechnet. In der Gruppe der beh. Patienten konnte eine signifikant höhere normalisierte Gesamtbindung von IMZ gefunden werden (p <0,001). Die spezifische Bindung von IMZ und die Gesamtbindung von HMPAO zeigten keine Unterschiede zwischen beiden Gruppen. Die IMZ-SPECT hatte in unserem Kollektiv gegenüber der HMPAO-SPECT in bezug auf das EEG eine höhere Sensitivität bei geringerer Spezifität im Nachweis einer Minderanreicherung des Tracers in Arealen mit fokaler hypersynchroner Erregungssteigerung.

Summary

The purpose of this study was to compare HMPAO- and IMZ-SPECT findings in treated and untreated patients with focal epilepsies. We examined 20 patients (untreated 13; treated 7). All patients had a normal CT and/or MRI scan. In all patients both whole-brain activity and regional count density (red) were evaluated by SPECT. Furthermore, the specific and non-specific binding of IMZ were calculated for each ROI and the results of both, treated and untreated patients were compared. Our data indicate that the normalized cerebral total binding of IMZ was significantly increased in all regions in the group of treated patients (p <0.001). In contrast, no difference in the tracer binding was found with HMPAO-SPECT We conclude that the difference in the IMZ-binding might be due either to exogenous or endogenous factors. In our study IMZ-SPECT had a higher sensitivity and a lower specificity in the detection of decreased red in areas with EEG findings that indicate an epileptogenic focus compared with HMPAO-SPECT.

Schlüsselwörter:

Fokale Epilepsie - SPECT - [^99mTc]-HMPAO - [¹²³J]-lomazenil - spezifische und unspezifische Bindung

Key words

Focal epilepsy - SPECT - [Tc-99m]-HMPAO - [1-123]-lomazenil - specific and nonspecific binding

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