Dynamic magnetic-resonance cystography in diagnosis of perivesical fat invasion in bladder cancer

Abstract

Objective: to evaluate the diagnostic capabilities of the dynamic magnetic-resonance cystography technique in detecting invasion of perivesical fat in case of bladder cancer.Materials and methods. The study included 125 patients (105 male and 20 females, mean 62.6 Ѓ} 11.0 years) with transitional cell carcinoma of the bladder. To assess the accuracy of the dynamic cystography method, cases with a tumor size of more than 20 mm, affecting the wall outside the bladder triangle, were selected with suspicion of perivesical fat invasion on magnetic-resonance scans. A furacilin solution was fractional injected into the catheterized bladder to obtain repeated series of T2‑haste-FS images until the bladder was completely expanded.Results. In postprocessing, the selection of areas of interest (ROI) was performed along the contour of the affected wall in the cross section through the center of the tumor. Comparison of the displacement of the affected and intact walls by a diagram of the values of the intensity of the magnetic-resonance signal in the dynamics of bladder dilatation was evaluated. The verification method was the morphological study of the surgical material after the operative treatment. The limit of values with a more likely lesion of perivesical fat was found, which is less than 11 % of the intensity change of the magnetic-resonance signal in selected ROIs during bladder wall expansion.Conclusion. The effectiveness of dynamic magnetic-resonance cystography in the differential diagnosis of perivesical fat infiltration in bladder cancer is characterized by a sensitivity of 90.0 %, a specificity of 93.3 %, and an accuracy of 92.0 %. The proposed technique improves the accuracy of the magnetic resonance imaging method with suspected infiltration of perivesical fat and is well tolerated by patients.