Abstract Objective This study was undertaken to test whether arterial spin labeling (ASL) performs comparably to 2‐ 18 Ffluoro‐2‐deoxy‐D‐glucose positron emission tomography (FDG‐PET), the mainstay functional imaging technique, in pediatric lesional epilepsy, while avoiding radiotracer exposure and additional sedation. Methods We retrospectively included children with epilepsy due to focal cortical dysplasia, low‐grade epilepsy‐associated tumors, or hippocampal sclerosis who underwent standardized magnetic resonance imaging (MRI; including single‐delay ASL) and FDG‐PET during presurgical evaluation. Lesions, perilesional perfusion, and metabolic abnormalities were segmented and coregistered. Spatial overlap was quantified using DICE scores to compare functional modalities with each other (perfusion‐to‐metabolism: DICE P‐to‐M ), with the lesion (metabolism‐to‐lesion: DICE M‐to‐L ; perfusion‐to‐lesion: DICE P‐to‐L ), and, in seizure‐free children, with the resection cavity (lesion‐, metabolism‐, perfusion‐to‐resection cavity: DICE L‐/M‐/P‐to‐Post ). We also assessed the temporal stability of perilesional ASL abnormalities and the presence of remote ipsilateral/contralateral abnormalities. Equivalence testing used the Wilcoxon signed‐rank equivalence test with FDG‐PET as reference; Cohen κ quantified agreement for remote abnormalities. Results Fifteen children were included; median ages at FDG‐PET and ASL were 7.7 and 7.5 years; 53% required sedation. Median perilesional volumes were 11 339 mm 3 (FDG‐PET) and 10 791 mm 3 (ASL); both were larger under sedation ( p < .001). Perilesional volumes were equivalent ( p = .037). Median DICE M‐to‐L and DICE P‐to‐L were .3 and .4; equivalence was confirmed ( p < .001). Median DICE P‐to‐M was .7, indicating strong ASL–FDG‐PET concordance. In seizure‐free children following surgery, DICE M‐to‐Post and DICE P‐to‐Post were both .6 and equivalent ( p = .01). ASL findings were stable over time (DICE = .27–.75; n = 4 with repeat ASL). Remote ipsilateral abnormalities were common (ASL 73%, FDG‐PET 67%; κ = .53), with poor contralateral agreement ( κ = .12). Significance ASL yielded perilesional findings equivalent to FDG‐PET and showed comparable overlap with the resection cavity in seizure‐free children. As a radiation‐free technique embedded into routine MRI, ASL reduces logistics and avoids an additional sedation session. These findings support ASL as a practical alternative to FDG‐PET for presurgical workup, especially when FDG‐PET access is limited.
Gennari et al. (Sat,) studied this question.