Contrast‐enhanced Ultrasound Combined With Elastography for the Evaluation of Muscle‐invasive Bladder Cancer in Rats

Objectives By comparing with the control group, we evaluated the usefulness of contrast‐enhanced ultrasound (CEUS) combined with elastography for the assessment of muscle invasion by bladder cancer (MIBC) in a Sprague–Dawley (SD) rat model. Methods In the experimental group, 40 SD rats developed in situ bladder cancer (BLCA) in response to N‐methyl‐N‐nitrosourea treatment, whereas 40 SD rats were included in the control group for comparison. We compared PI, Emean, microvessel density (MVD), and collagen fiber content (CFC) between the two groups. In the experimental group, Bland–Altman test was used to assess the relationships between various parameters. The largest Youden value was used as the cut‐off point, and binomial logistic regression analysis was performed to analyze the PI and Emean. Receiver operating characteristic (ROC) curve analysis was performed to determine the diagnostic power of parameters, individually and in combination. Results The PI, Emean, MVD, and CFC were significantly lower in the control group than in the experimental group (P