Abstract

BACKGROUND AND PURPOSE: Interictal FDG-PET scans are a routine diagnostic technique for the identification of epileptogenic foci in the presurgical work-up of medically refractory pediatric epilepsy. With the advent of PET/MR imaging, it has become possible to simultaneously acquire FDG-PET and arterial spin-labeling perfusion data. The objective of this study was to evaluate whether the incorporation of arterial spin-labeling data with interictal FDG-PET could improve the diagnostic performance metrics of FDG-PET for identification of epileptogenic foci.MATERIALS AND METHODS: Forty-five pediatric patients with a mean age of 10.8years were retrospectively included in this study. These patients all underwent PET/MR imaging to diagnose suspected focal epilepsy.RESULTS: When compared to interpretations of interictal FDG findings alone, FDG combined with arterial spin-labeling findings resulted in significantly decreased sensitivity (0.64 versus 0.52, P=.02), significantly increased specificity (0.50 versus 0.75, P=.04), and an increased positive predictive value (0.59 versus 0.75). The decreased sensitivity was found to be primarily driven by patients with extratemporal lobe epilepsy, as a subgroup analysis showed decreased sensitivity for patients with extratemporal epilepsy (0.52 versus 0.38, P=.04), but not for temporal epilepsy (0.83 versus 0.75, P=.16). Additionally, substantial agreement between focal FDG hypometabolism and arterial spin-labeling hypoperfusion was demonstrated with the Cohen kappa (0.70, P<.01).CONCLUSIONS: These findings suggest that simultaneously acquired interictal FDG-PET and arterial spin-labeling data can improve the diagnosis of epileptogenic foci, especially in the setting of temporal lobe epilepsy where they improve specificity and positive predictive value, with preservation of sensitivity.

View details for DOI 10.3174/ajnr.A7421

View details for PubMedID 35210273