Preliminary study of diffusion-weighted MRI in the preoperative diagnosis of cystitis glandularis

Aim: To assess the efficacy of diffusion-weighted (DWI) magnetic resonance imaging (MRI) in distinguishing cystitis glandularis (CG) from bladder urothelial carcinoma. Materials and methods: Ultrasound, computed tomography (CT), conventional MRI, and DWI of 30 patients with histopathologically confirmed CG were analysed retrospectively and the imaging findings were correlated to the findings at histology. Results: Ultrasound was non diagnostic in 11/18 and misdiagnosed malignancy in 7/18; CT was non diagnostic in 6/10 and misdiagnosed malignancy in 4/10; MRI was non diagnostic in 0 and misdiagnosed malignancy in 4/5 respectively. One patient with diffuse bladder wall thickening was correctly diagnosed as CG at MRI. All six patients who underwent additional DWI were accurately diagnosed as having CG with no or minimal reduction of diffusion. Conclusions: Diffusion is not reduced or shows minimal reduction in CG. DWI may aid the differential diagnosis of CG. - Highlights: • The use of diffusion weighted imaging (DWI) is proposed to distinguish cystitis glandularis from carcinoma. • DWI is non-invasive, easy to perform, time saving and requires no contrast agents. • No other imaging protocol has shown better discrimination than DWI in this context.