Clinical experience of MRI in two dogs with muscle-invasive transitional cell carcinoma of the urinary bladder.

This study described high-field magnetic resonance imaging (MRI) and computed tomography (CT) characteristics of muscle-invasive bladder transitional cell carcinoma (TCC) in two dogs. Ultrasonography revealed a urinary bladder mass with ambiguous result about invasion to the muscular layer. Contrast-enhanced CT showed that the bladder wall in which the mass was attached was more intensely enhanced than the normal bladder walls, supporting invasion to the muscular layer. The mass revealed an intermediate signal intensity with interruption of the hypointense muscular layer on T2-weighted MRI and showed greater enhancement compared with the normal bladder wall on postcontrast T1-weighted images. T2-weighted MRI, postcontrast T1-weighted MRI and contrast-enhanced dual-phasic CT were useful for evaluating muscle-invasive bladder TCC in dogs.