Clinical application of two-dimensional transvaginal ultrasound combined with contrast-enhanced ultrasound for the diagnosis and preoperative evaluation of cesarean scar pregnancy.

AIM: To determine if contrast-enhanced ultrasound (CEUS) improves the diagnostic performance of conventional two-dimensional transvaginal ultrasound (2DTVUS) in cesarean scar pregnancy (CSP). MATERIAL AND METHODS: This retrospective cohort study included patients with suspected CSP who were evaluated between January 2021 and June 2025. All the patients underwent both 2DTVUS and CEUS. 2DTVUS was used to assess myometrial thickness at the scar, gestational sac protrusion, and vascularity. CEUS was used to evaluate the enhancement pattern, time-to-peak, and peak intensity relative to the adjacent myometrium. RESULTS: Histopathology confirmed 63 cases of CSP and 43 cases of non-CSP among the 106 patients who subsequently underwent pregnancy termination. 2DTVUS identified 95 cases as CSPs and 11 as non-CSPs, whereas CEUS identified 66 cases as CSPs and 40 as non-CSPs. Compared with 2DTVUS, CEUS showed higher specificity (97.6% vs. 63.4%, p<0.001), sensitivity (96.9% vs. 92.3%), accuracy (97.2% vs. 81.1%, p<0.001), positive predictive value (98.4% vs. 80.0%, p=0.0018), and negative predictive value (95.2% vs. 83.9%). ROC analysis demonstrated that CEUS had a higher AUC than 2DTVUS (0.972 vs. 0.779, p<0.001). CONCLUSION: CEUS complements 2DTVUS by sensitively depicting microvascular perfusion and quantifying the relationship between the gestational sac and the cesarean scar, thereby improving diagnostic accuracy and facilitating preoperative planning in patients with suspected CSP.