COMPARING ULTRASOUND AND MRI OF SCARRED MYOMETRIUM

To determine whether ultrasound (US) or magnetic resonance imaging (MRI) gave more accurate and objective information about the thickness and continuity of scarred isthmical myometrium following previous Caesarean section (CS), US and MRI assessments of the scarred myometrium in 10 pregnant women (37-41 weeks gestation) after 1-8 CS were compared with each other and with findings at subsequent elective CS. Vaginal ultrasound gave more accurate information about the condition of the scarred isthmical myometrium than MRI, since US always allowed precise differentiation of isthmical myometrium from the urinary bladder wall and thus measurements of the scar thickness; there was a good correlation to intraoperative observations. MRI achieved better contrast resolution with T2- than T1-weighted and proton density-weighted spin-echo sequences. However, differentiation of the various tissues was either impossible (T1- and protondensity-weighted sequences) or less informative than with US. Image quality of body and posterior wall of the uterus was better with MRI (T2-weighted sequence) than with US.