Three-Dimensional Measurement of the Uterus on Magnetic Resonance Images: Development and Performance Analysis of an Automated Deep-Learning Tool.

Uterus measurements are useful for assessing both the treatment and follow-ups of gynaecological patients. The aim of our study was to develop a deep learning (DL) tool for fully automated measurement of the three-dimensional size of the uterus on magnetic resonance imaging (MRI). In this single-centre retrospective study, 900 cases were included to train, validate, and test a VGG-16/VGG-11 convolutional neural network (CNN). The ground truth was manual measurement. The performance of the model was evaluated using the objective key point similarity (OKS), the mean difference in millimetres, and coefficient of determination R2. The OKS of our model was 0.92 (validation) and 0.96 (test). The average deviation and R2 coefficient between the AI measurements and the manual ones were, respectively, 3.9 mm and 0.93 for two-point length, 3.7 mm and 0.94 for three-point length, 2.6 mm and 0.93 for width, 4.2 mm and 0.75 for thickness. The inter-radiologist variability was 1.4 mm. A three-dimensional automated measurement was obtained in 1.6 s. In conclusion, our model was able to locate the uterus on MRIs and place measurement points on it to obtain its three-dimensional measurement with a very good correlation compared to manual measurements.

Pregnancy in a rudimentary horn: multicenter's MRI features of a rare condition.

PURPOSE: To describe the MRI features of rudimentary horn pregnancy (RHP) with surgical correlations. METHODS: Nine women with a RHP underwent preoperative pelvic MRI. MRI protocol included T2- (n = 9), T1- (n = 7), and fat-suppressed contrast-enhanced T1-weighted sequences (n = 4). Two pelvic radiologists retrospectively analyzed MR images to assess the following MRI features: presence of a myometrium around the gestational sac (GS) and characteristics of its wall, GS surrounded by myometrium in contact with the round ligament, communication of the GS with the endometrial cavity of the main horn, continuity of the GS with the cervix, fibrous or muscular GS attachment to the main horn, lateral deviation, and endometrial thickness of the main horn. Ovaries and tubes were also assessed. MRI features were correlated with surgical findings. RESULTS: Seven of the nine women [29 ± 6 SD years (range 16-37 years)] underwent surgical management. The first US diagnosed RHP in only 1/9 patients. All pregnancies were diagnosed using MRI. RHP was all located in the rudimentary horn of a unicornuate uterus. All the GS was surrounded by myometrium in contact with the round ligament. None of the RHP displayed communication with the endometrial cavity of the main horn nor with the cervix. An attachment between the RHP and the main horn was seen in 3/9 patients. All the main horns were lateralized and empty. CONCLUSION: MRI diagnosed RHP in all patients by identifying the GS surrounded by myometrium in contact with the round ligament and the absence of continuity between the GS and the cervix. LEVEL OF EVIDENCE: IV-retrospective study.

Involvement of small bowel in systemic disease: CT and MR imaging finding.

Computerized tomography (CT) and magnetic resonance imaging (MRI), particularly MR Enterography, are the standard cross-sectional imaging modalities used to study small bowel involvement in a context of multiorgan disease. Clinical symptoms are generally nonspecific in such cases. Moreover, imaging findings of the different conditions often overlap. However, analysis of the location, distribution of the lesions on the small bowel wall, as well as of the rest of the bowel and of distant organs, may help narrow the spectrum of diagnoses of multiorgan conditions involving both the small bowel and other organs. The purpose of this presentation is to review and illustrate the CT and MRI features of small bowel involvement in systemic disease. Based on the underlying mechanism, we will categorize them as follows: congenital/hereditary, immunologic, infiltrative, vascular, infectious and miscellaneous.