Adenomyosis is a medical condition characterized by the presence of ectopic endometrial tissue (the inner lining of the uterus) within the myometrium (the thick, muscular layer of the uterus).
The condition is typically found in women in the ages between 35 and 50. Patients with adenomyosis can have painful and/or profuse menses (dysmenorrhea & hypermenorrhea, respectively).
Adenomyosis may involve the uterus focally (creating an adenomyoma) or diffusely. With diffuse involvement, the uterus becomes bulky and heavier.
Diagnosis
The uterus may be imaged using ultrasound (US) or magnetic resonance imaging (MR). Transvaginal ultrasound is the most cost effective and most available. Either modality will show an enlarged uterus. On ultrasound, the uterus will have a heterogeneous texture, without the focal well-defined masses that characterize uterine fibroids.
MR provides better diagnostic capability due to the increased spatial and contrast resolution, and to not being limited by the presence of bowel gas or calcified uterine fibroids (as is ultrasound). In particular, MR is better able to differentiate adenomyosis from multiple small uterine fibroids the uterus will have a thickened junctional zone with diminished signal on both T1 and T2 weighted sequences due to succeptibility effects of iron deposition due to chronic microhemorrhage. A thickness of the junctional zone greater than 10 or 12 mm (depending on who you read) is diagnostic of adenomyosis (<8 mm is normal). Interspersed within the thickened, hypointense signal of the junctional zone, one will often see foci of hyperintensity (brightness) on the T2 weighted scans representing small cystically dilatated glands or more acute sites of microhemorrhage.
MR can be used to classify adenomyosis based on the depth of penetration of the ectopic endometrium into the myometrium.
Treatment
Treatment options range from use of NSAIDS & hormonal suppression for symptomatic relief, to endometrial ablation or hysterectomy for a more or less permanent cure.
Other considerations
The differential of abnormal uterine bleeding includes
- endometrial polyps
- submucosal fibroids
- endometrial hyperplasia
- endometrial carcinoma
- post-menopausal atrophy
In a younger woman, considerations should be broadened to include
- spontaneous abortion
- ectopic pregnancy
Prognosis
There is no increased risk for cancer development. As the condition is estrogen-dependent, menopause presents a natural cure. Patients with adenomyosis often also have leiomyomata and/or endometriosis.