Uterine adenomyosis with extensive glandular proliferation: Case series of a rare imaging variant

Abstract

PURPOSE We aimed to investigate the clinical and magnetic resonance imaging (MRI) characteristics of uterine adenomyosis, which presents as an extensive area of high signal intensity in the myome-trium on T2-weighted MRI. METHODS This retrospective radiographic study reviewed a case series of six patients (mean age, 36 years) with adenomyosis. These patients were selected because, unlike classical adenomyosis, T2-weighted images showed a larger area of high signal intensity than that of low signal intensity in the myometrium. The morphology of the myometrial lesions, patterns of contrast enhancement (n=4), intramyometrial hemorrhaging, diffusion restriction (n=5), endometrial lesions, and imaging findings after treatment (n=3) were evaluated on MRI. RESULTS The patients’ clinical symptoms included vaginal bleeding and severe anemia. Four were admin-istered hormonal therapy, one underwent hysterectomy, and one underwent enucleation. On T2-weighted images, all showed endometrial thickening and a high signal intensity area in the myometrium that was divided up by a mesh of low signal intensity bands, with an appearance reminiscent of a fish caught in a net. Other findings included gradual centripetal enhancement with contrast defects in multicystic areas (4/4), an intramyometrial hemorrhage (1/6), and in-creased diffusion (5/5). Following hormonal therapy, the uteruses decreased in size and were similar to those of classical adenomyosis on MRI (3/3). The lesions were diagnosed as adenomy-osis with a proliferation of adenomyotic glandular tissue and a proliferative endometrial polyp. CONCLUSION This case series suggests that there is a subgroup of uterine adenomyosis that shows a characteristic “fish-in-a-net” appearance on T2-weighted images.