Uterine contrast-enhanced ultrasound (CEUS): new insights into adenomyosis using an innovative technique

Objectives: Heavy menstrual bleeding, dysmenorrhea and subfertility are associated with adenomyosis, a benign uterine condition characterised by ectopic endometrium within the myometrium. Currently, diagnosing adenomyosis is challenging. Imaging the uterine microcirculation using contrast-enhanced ultrasound (CEUS) may improve diagnostics. We aimed to 1) determine the feasibility of transvaginal two-dimensional (2D) uterine CEUS, 2) compare features of adenomyosis on 2D CEUS with conventional ultrasound and Magnetic Resonance Imaging (MRI), and 3) qualitatively and quantitatively analyse 2D CEUS scans of patients with adenomyosis. Methods: We included ten pre-menopausal adult patients with prominent direct Morphological Uterus Sonographic Assessment (MUSA) features of adenomyosis on B-mode. MRI scans were collected when clinically available. Conventional ultrasound and a 3-min transvaginal 2D CEUS scan were performed and analysed. Uterine wash-in and wash-out of the contrast agent were analysed qualitatively, and quantitatively using time-intensity curve parameters. Results: Performing transvaginal CEUS scans was feasible, providing good visualisation of uterine macro- and microcirculation. CEUS visualised smaller and deeper-lying blood vessels than Doppler ultrasound. In the myometrium, non-to hypo-enhanced areas interspersed with hyper-enhanced regions, and vessels with enlarged lumen were observed. Hyper-echoic islands on B-mode showed either hypo- or hyper-enhancement on CEUS. Qualitative analysis and time-intensity maps showed clear heterogeneous myometrial perfusion in all patients with adenomyosis. Conclusions: Transvaginal CEUS is a feasible technique for qualitative and quantitative analysis of the uterine macro- and microcirculation. It holds promise as a diagnostic imaging modality for adenomyosis.