Comparison of scar thickness measurements using trans-vaginal sonography and MRI in cases of pregnancy with previous caesarean section. Do they correlate with actual scar thickness?

The aim of this study was to evaluate scar thickness in cases of pregnancy with previous caesarean section, by trans-vaginal sonography (TVS) and magnetic resonance imaging (MRI), and to correlate precision of radiologically-measured scar thickness with actual measurement of scar thickness. A total of 35 pregnant patients with previous caesarean section planned for elective caesarean section, were evaluated prospectively. Their scar thickness was measured by TVS and MRI on the day of elective repeat caesarean section. These measurements were correlated with each other and with scar thickness measured during elective repeat caesarean section by using a caliper. The correlation coefficients between scar thickness measured by TVS and MRI with peroperative evaluation with a caliper, were +0.72 and +0.59, respectively. The study concluded that as MRI is a costlier modality and TVS has better correlation coefficient with actual scar thickness, TVS can be considered to be the better modality for antenatal scar thickness measurement.