Application of Magnetic Resonance Imaging Report Combined With VI-RADS Bi-Parametric and Multi-Parametric Scoring Systems in Bladder Cancer Diagnosis

Objective To verify by retrospective analysis the performance of applying dual-parametric (T2 weighted image T2WI and diffusion weighted image DWI) and multi-parametric (T2WI, DWI, and dynamic contrast enhance DCE) evaluation systems of Vesical Imaging-Reporting and Data System (VI-RADS) in the magnetic resonance imaging (MRI) diagnosis of bladder cancer.

Methods The imaging and clinical data of bladder cancer patients who underwent bladder MRI examination in the Department of Urology of our hospital between January 2020 and December 2021 were collected. A total of 215 bladder cancer patients, among whom there were 183 males and 32 females with an average age of (67.60±11.42) years, were included. The bladder cancer diagnosis of all the cases was verified by pathology analysis of tissue samples. Two radiologists, who were double-blinded, scored multiple sequences separately. Then, a comparative analysis was made on the diagnostic performance of dual-parametric and multi-parametric VI-RADS diagnostic scores. The diagnostic test with receiver operator characteristic (ROC) curves and Cohen's Kappa were used to evaluate the diagnostic efficacy and consistency.

Results The area under the curve (AUC) and 95% confidence interval (CI) of the multi-parametric VI-RADS evaluation system by the two radiologists in the overall population were 0.878 (0.830-0.925) and 0.856 (0.805-0.907), while those for the bi-parametric VI-RADS evaluation system were 0.889 (0.844-0.934) and 0.856 (0.805-0.907), showing no statistically significant difference. No significant difference was observed in the subgroup analysis of patients who underwent transurethral resection of bladder tumor (TURBT). Furthermore, the Kappa values for inter-rater agreement between of the two radiologists were 0.694 and 0.546 (with the VI-RADS score≥3 defined as being positive) and 0.693 and 0.712 (with the VI-RADS score≥4 defined as being positive) in multi-parametric and bi-parametric evaluation, respectively (all P<0.001).

Conclusion The bi-parametric VI-RADS scoring system can achieve a diagnostic efficacy comparable to that of the multi-parametric scoring system, offering an alternative to patients who are unable to undergo contrast-enhanced MRI due to allergic reaction to contrasts.