Comparison of magnetic resonance imaging with computed tomography and intravesical ultrasound in staging bladder cancer.

Magnetic resonance imaging (MRI), computed tomography (CT), and intravesical ultrasound (US) scanning were performed on 11 patients in whom infiltrative bladder cancer was suspected at cystoscopy. Equipment with magnetic field 0.02 T was used for the MRI. Tumors larger than 2 cm could be identified in all cases by MRI. In 3 of 4 cases in which the tumor was smaller than 2 cm, it could not be properly visualized and the degree of infiltration could not be assessed. When the tumor was visualized on MRI, tumor staging by MRI was correct in 7 of 8 cases (88%). Infiltration of the deep muscle layer of the bladder wall could be detected by MRI but not by CT. Intravesical US staging was correct in 7 of 9 cases (78%). As a noninvasive method, MRI is promising for the preoperative evaluation of bladder cancer and offers the advantage of imaging the bladder in different planes.