Abstract:

Background and purpose: ¹⁸F-FDG has been considered to be of limited value for the detection of bladder lesions because of interference by the ¹⁸F-FDG excreted in urine. Delayed pelvic images with “diluted and filled bladder” use a method of ¹⁸F-FDG PET/CT with delayed images after oral hydration so as to increase the detection rate of 18F-fluorodeoxyglucose(FDG) PET/CT imaging for the lesions of bladder. Methods: 48 patients with bladder lesions(35 patients with bladder primary tumor and 13 patients with metastatic tumor) underwent ¹⁸F-FDG PET/CT detection and were required oral hydration of 1200-1800 mL water, urination frequently, holding urine when the more scan began. Lesions confirmed by histopathology, MRI, CT or clinical follow-up at least 1 year. Results: 89%(43/48) of patients were obtained good clearance and the urine SUV_max declined from 33.14(9-66.80)to 3.23(1.35-5.65) significantly and the statistical difference was significant (t=8.703, P<0.01). The interval time between two scan was 2 h approximately. At the same time, the SUV_max of bladder lesion was 2.8-25.0. Detection sensitivity, specificity and accuracy were 90.47%(19/21), 81.48%(22/27)and 85.41%(41/48), respectively. Conclusion: ¹⁸F-FDG activity in the bladder significantly decreased in most patients with “diluted and filled bladder”. The PET/CT scan can highly detect lesions of bladder tissues. Our method with high accuracy and better endurance could be applied to detect the lesions in bladder.

Key words: Urogenital neoplasms, Positron emission tomography, Computed X-ray tomography, ¹⁸F-fluorodeoxyglucose