Efficacy of 18F-FDG PET/CT guided botulinum toxin therapy in idiopathic cervical dystonia

256 Objectives Preliminary study suggested that 18F-FDG PET/CT might be useful to find hypermetabolic dystonic muscles in patients with idiopathic cervical dystonia (ICD) (Sung DH, et al. J Nucl Med. 2007). We investigated the therapeutic efficacy of 18F-FDG PET/CT guided botulinum toxin (BT) treatment in ICD compared with that of conventional BT therapy on literature. Methods Subjects were 57 patients (M:F = 29:28 ; mean age, 46 ± 12 y, range 19-69 y) with ICD, who underwent clinical assessment, needle electromyography (EMG) and 18F-FDG PET/CT to localize dystonic muscles. Based on the results of those studies, BT was injected into target cervical muscles. To evaluate the therapeutic efficacy, Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) were measured in each patient before and 4 weeks after the treatment. This efficacy was compared with the result of conventional BT therapy on literature where PET/CT was not included as a part of localization work-up. Results The TWSTRS was improved in 52 of 57 patients (91.2%) with ICD after PET/CT guided BT therapy. Hypermetabolic cervical muscles on PET/CT were identified in 53 of 57 patients (92.9%), Especially, in 22 of 57 patients (38.6%), PET found abnormal hypermetabolic deep cervical muscles, where EMG couldn’t access. When at least 30% decrease in TWSTRS total score was considered significant improvement, the therapeutic efficacy of PET/CT guided BT therapy was 70.2% (40/57), which was significantly higher than 49.1% (27/55) of conventional BT therapy (Truong D, et al. Parkinsonism Relat Disord. 2010, p Conclusions 18F-FDG PET/CT guided BT therapy may be more effective than conventional BT therapy for treating patients with ICD.