<b>Assessment of changes in the cesarean scar and uterus between one and two years after previous cesarean section using 3D T2w SPACE MRI</b>

To evaluate changes in morphology of the cesarean scar and uterus between one and two years after a previous cesarean section (p-CS) using high-resolution, three dimensional T2-weighted sampling perfection with application optimized contrast using different flip angle evolutions Magnetic Resonance Imaging (3D T2w SPACE MRI).This prospective study was performed to investigate morphological changes in the cesarean scars and uterus from one to two years after p-CS using high-resolution, 3D T2w SPACE MRI. The healthy volunteers with no childbearing history were recruited as controls. All data were measured by two experienced radiologists. All data with a normal distribution between the one-year and two-year groups were compared using a paired-sample t test or independent t test.Finally, 46 women took a pelvic MR examination one year after p-CS, and a subset of 15 completed the same examination again after two years of p-CS. Both the length of uterine and thickness of the myometrium after two years of cesarean section (5.75 ± 0.46 vs. 1.45 ± 0.35 cm) were significantly greater than those measured at one year (5.33 ± 0.59 vs. 1.25 ± 0.27 cm) (t = -2.363, -2.175, P= 0.048, 0.033). No significant difference was shown in myometrial thickness two years after p-CS (1.45 ± 0.35 cm) with respect to the control group (1.58 ± 0.21 cm) (P=0.170). Nine women were considered to have scar diverticula one year after p-CS, and still had diverticula two years after p-CS. The thickness, height, and width of the uterine scar showed no significant change from one to two years (P > 0.05).3D T2w SPACE MRI provides overall morphologic details and shows dynamic changes in the scar and the uterus between one and two years after p-CS. Scar morphology after p-CS reached relatively stable one year after p-CS, and uterine morphology was closer to normal two years after p-CS.