Evaluation the activity of alveolar echinococcosis: A comparison between 18F-FDG PET and spectral CT

Abstract

PurposeTo assess the iodine concentration of hepatic alveolar echinococcosis (HAE) using spectral computed tomography (CT) with comparison of [18F] fluorodeoxyglucose positron-emission tomography (18F-FDG PET), and to estimate the value of spectral CT for evaluation of HAE activity. Materials and methods18 patients with histologically confirmed or clinically proved HAE underwent spectral CT and 18F-FDG PET examinations. After three-phase scanning, the quantitative iodine-based material decomposition images and optimal monochromatic image of spectral CT were reconstructed and iodine concentration (IC) was measured in different organizational structures. Results18F-FDG PET identified increased metabolic activity in the corresponding lesions in 13 patients (13/18, 72.2%). The iodine concentration in marginal zone of lesion were significantly higher than in solid component of lesion and normal liver parenchyma during PVP and VP. The iodine value of edge tissue of the lesion and normal liver and iodine value of normal liver tissues showed statistically significant difference (P < 0.001). There was correlation between IC and SUVmax in marginal zone of HAE lesion, it was highest during PVP (r = 0.873, p < 0.001). There was low correlation between CT values and SUVmax. ConclusionThere was good correlation between spectral CT and 18F-FDG PET. Spectral CT could be recommended as a more practical tool in the clinical routine.