2D and 3D ultrasound assessment of cesarean section scars and its correlation to intraoperative findings

Objective: to investigate the accuracy of 2D and 3D ultrasound in measurement of Cesarean section (CS) scar thickness. Study design: A prospective observational study conducted on 75 pregnant women with previous 1 or 2 CS candidates for elective CS. Evaluation of LUS using 2D and 3D transabdominal and transvaginal ultrasound is then correlated to scar integrity assessed intraoperatively. Results: Five cases had scar dehiscence with incidence of 6.67%. Dehiscence showed a statistically significant difference between women with previous 2 CS and those with previous 1 CS (4 vs. 1 respectively). The best cut-off value for 2D and 3D transabdominal ultrasound was 3.8 and 5.0 mm, with AUC of 0.737and 0.824, yielding a sensitivity of 60% and 100%, specificity of 91.4% and 62.86% respectively .The best cut-off value for 2D and 3D transvaginal ultrasound was 2.0 and 1.9 mm with AUC of 0.931 and 0.974 with sensitivity of 100% and 100%, specificity of 65.71% and 87.14% respectively. Conclusion: ultrasound is a reliable method for measuring the LUS thickness and scar integrity in patients with previous CS. The use of transvaginal 3D ultrasound in measuring the muscular layer thickness of LUS is the most reliable route with high sensitivity and specificity.