The effectiveness of shear wave elastosonography for cesarean scar in myometrium of pregnancy with A cesarean BİRTH history and its contribution to delivery planning

Objective: The aim of this study is to examine the changes made by cesarean scar in myometrial elasticity of pregnant women by using B-mode ultrasound (US) and shear wave elastography (SWE) imaging methods and to contribute to the determination of the delivery method in pregnant women with cesarean section history. Materials and Methods: 120 pregnant women between 28-32 weeks of gestation were included in the prospective study. 60 of these pregnant women had cesarean section history and rest 60 of them had normal delivery history. Thirty of the pregnant women who had a cesarean delivery had one previous cesarean section and the other 30 had two previous cesarean sections. Thirty of the pregnant women who had a normal delivery had a history of one, and the other 30 had a history of two previous normal deliveries. Myometrium SWE and thickness measurement were performed from the point where the cesarean scar was visualised. In patients with non visualisable cesarean scar with US or had normal delivery, measurements were made approximately 2 cm above the upper border of the bladder, which is the cesarean section incision line. Results: Mean myometrial stiffness were 9.6 ± 3.22 kPa in pregnant women who had a normal delivery, and 21.33 ± 9.18 kPa in pregnant women who had a cesarean delivery. There was a statistically significant difference between the two groups (p<0.001). In terms of subgroups; myometrial stiffness was 10.07 ± 3.24 kPa in the ND1 group, 9.14 ± 3.19 kPa in the ND2 group, 21.86 ± 10.54 kPa in the SZ1 group and 20.80 ± 7.74 kPa in the SZ2 group. The difference between SZ1 and ND1 subgroups and between SZ2 and ND2 subgroups was statistically significant (p<0.001, p<0.001, respectively). Considering the time elapsed after cesarean section, the elasticity value of cases less than two years of interdelivery period was 32.78 ± 12.14 kPa for the SZ1 group, 23.48 ± 3.84 kPa for the SZ2 group and 28.9 ± 10.42 kPa for all cesarean section patients.. The elasticity value was found to be 24.72 ± 6.23 kPa for the SZ1 group, 23.61 ± 7.54 kPa for the SZ2 group and 24.01 ± 6.98 kPa for all cesarean section patients in cases two to five years of interdelivery period. In cases with more than five years of interdelivey period, the elasticity value was measured as 14.55 ± 5.35 kPa for the SZ1 group, 14.3 ± 5.96 kPa for the SZ2 group, and 14.45 ± 5.46 kPa for all cesarean section patients. The difference between all groups was statistically significant (p<0.001). There was no statistically significant difference between the groups in terms of median and mean myometrium thicknesses. Conclusion: The myometrial stiffness of the pregnant women who had cesarean delivery was significantly higher than the women who had normal delivery. In this study, myometrial stiffness value was found to be significantly higher in cases whose measurements were performed less than 2 years after the previous cesarean section. It was observed that the elasticity value of pregnant women who have passed 5 years or more after cesarean section approaches to the stiffness of pregnant women who had a normal delivery. We assume that ultrasound elastography can be used as an important parameter to guide pregnant women who have had cesarean section to normal delivery. These data need to be supported by studies with larger numbers of pregnant women and more categorized interdelivery times. Keywords: Cesarean scar, Elastography, Ultrasonography.