Feasibility study of the application of magnetic resonance elastography to diagnose uterine adenomyosis

Objective

Magnetic resonance elastography (MRE), a novel imaging technique that allows in vivo measurement of tissue mechanical properties, was used to test the prediction that the stiffness of the uterus may be increased due to fibrotic changes in patients with adenomyosis.

Design

A feasibility study in which a 3-dimensional (3D) MRE imaging protocol was developed to measure the stiffness of the tissues of the uterus.

Subjects

Four patients with suspected adenomyosis and heavy menstrual bleeding diagnosed via transvaginal ultrasound and clinical history and 1 healthy control were recruited. Two patients underwent hysterectomy, and histologic analysis of the tissue samples was performed.

Main Outcome Measures

The stiffness of the whole uterus was obtained by region of interest analysis of the 3D MRE images for the 4 patients and 1 healthy control. In addition, for the 2 patients who underwent hysterectomy, the uterine tissue samples were assessed to determine histologic presence of adenomyosis via hematoxylin and eosin staining, cellular/molecular measures of tissue stiffness (collagen [picrosirius red], α-smooth muscle actin, and e-cadherin), and whether a relationship existed between in vivo assessment of the uterus via 3D MRE and in vitro uterine tissue histology.

Results

3D MRE was successfully used to acquire elastograms for 4 patients with adenomyosis (diffuse, n = 3; focal, n = 1) and 1 healthy control. Calculated global uterine stiffness was higher in women with adenomyosis (2.93 kPa; range, 2.34–3.39 kPa) than in the healthy control (2.04 kPa). Regions of high stiffness on the 3D elastograms reflected adenomyotic changes visualized via conventional magnetic resonance imaging and were correlated with histologic and immunohistochemical markers of tissue stiffness.

Conclusion

3D MRE has the potential to provide non-invasive characterization of changes in the mechanical properties of uterine tissue that is not possible using conventional magnetic resonance imaging or transvaginal ultrasound. Further studies are needed to confirm the efficacy of the 3D MRE protocol for diagnosing adenomyosis.