Vergleichende Untersuchung am unteren Uterinsegment nach Sectio caesarea mittels Ultraschall und Magnetresonanztomographie

Abstract

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.

Comparison of the lower uterine segment in pregnant women with and without previous cesarean section in 3 T MRI

“…With fast T2-weighted sequences, relevant uterine structures and particularly the very thin LUS can be reliably visualized, independent of ultrasound limitations. Due to the higher field strength of 3 T, spatial resolution and tissue contrasts were better in our study than those in previous studies using 1.5 T [11, 12]. Consistent with previous studies, our data indicate that urinary bladder filling level does not influence LUS thickness, and thus, a partial filling level might be preferred for better patient comfort [8].…”

“…As a complementary and safe noninvasive imaging modality during pregnancy, MRI is a highly interesting approach but not yet sufficiently investigated [11–14]. With our recent scientific results we demonstrated MRI to be an adequate additional noninvasive image modality for prenatal LUS diagnostics in patients with previous CS.…”

Sonographic assessment of lower uterine segment thickness preoperative vs. intraoperative assessment in women with previous cesarean

“…The main limitation of frequent using of TVS it's that it may cause discomfort and difficulty in at term women. 19 The study by Cheung et al suggests that US surveillance for a defective LUS could be possible, but the population of his study was small, and the observers were not blinded. These preclude accurate estimates and limit the ability to establish clinically useful relationships.…”