Semiquantitative dynamic contrast-enhanced MRI for accurate classification of complex adnexal masses.

PURPOSE: To identify the best dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) descriptive parameters in predicting malignancy of complex ovarian masses, and develop an optimal decision tree for accurate classification of benign and malignant complex ovarian masses. MATERIALS AND METHODS: Preoperative DCE-MR images of 55 sonographically indeterminate ovarian masses (27 benign and 28 malignant) were analyzed prospectively. Four descriptive parameters of the dynamic curve, namely, time-to-peak (TTP), wash-in-rate (WIR), relative signal intensity (SIrel ), and the initial area under the curve (IAUC60 ) were calculated on the normalized curves of specified regions-of-interest (ROIs). A two-tailed Student's t-test and two automated classifiers, linear discriminant analysis (LDA) and support vector machines (SVMs), were used to compare the performance of the mentioned parameters individually and in combination with each other. RESULTS: TTP (P = 6.15E-8) and WIR (P = 5.65E-5) parameters induced the highest sensitivity (89% for LDA, and 97% for SVM) and specificity (93% for LDA, and 100% for SVM), respectively. Regarding the high sensitivity of TTP and high specificity of WIR and through their combination, an accurate and simple decision-tree classifier was designed using the line equation obtained by LDA classification model. The proposed classifier achieved an accuracy of 89% and area under the ROC curve of 93%. CONCLUSION: In this study an accurate decision-tree classifier based on a combination of TTP and WIR parameters was proposed, which provides a clinically flexible framework to aid radiologists/clinicians to reach a conclusive preoperative diagnosis and patient-specific therapy plan for distinguishing malignant from benign complex ovarian masses. LEVEL OF EVIDENCE: 2 J. Magn. Reson. Imaging 2017;45:418-427.

Appearance of uterine scar due to previous cesarean section on hysterosalpingography: various shapes, locations and sizes.

Hysterosalpingography (HSG) is the radiographic evaluation of the uterus and fallopian tubes that is used predominantly in the assessment of infertility and evaluation of abnormalities of the uterus and fallopian tubes. Some of the abnormalities that can be detected by HSG include congenital anomalies, polyps, leiomyomas, synechiae and adenomyosis. HSG is also used to evaluate any scarring on the uterus and fallopian tubes. Cesarean section is the most commonly performed surgical procedure involving the uterus in fertile women. Cesarean section involves an incision made in the lower uterine segment or isthmus. Various changes in the site of the cesarean incision may be seen due to wall weakness and fibrosis. The scar may have various shapes; unilateral or bilateral, single or multiple, wedge-shaped or linear. Awareness of the appearance and locations of uterine defects due to previous cesarean section is necessary in order to differentiate them from normal variations and other pathologies mimicking it. In this study, we demonstrate the appearance of anatomic defects of the uterine cavity on HSG after cesarian section. We define different shapes such as thin linear defect, focal saccular outpouching, unilateral or bilateral diverticula (dog-ear like) and fistula and different locations such as the uterine body, lower uterine segment, uterine isthmus and the upper endocervical canal.