Adenomyosis is thought to be a disorder of the junctional zone (JZ), the interface between the endometrium and myometrium. Although not cancer, it can cause severe symptoms that negatively impact quality of life.
According to a 2016 review published in the Journal of Minimally Invasive Gynecology, adenomyosis is a fairly common condition with a prevalence that varies widely, from 5 percent to 70 percent. In the past, the pathologist evaluating a hysterectomy specimen made this diagnosis. Today, an alert clinician using adenomyosis ultrasound can sync the diagnosis in the office long before a surgical procedure.
To better understand this disorder, let's take a look at the five W's — and one H — of adenomyosis.
What Causes Adenomyosis?
Injury, infection and even pregnancy have been blamed as potential stimuli that cause the endometrium to grow into the myometrium, where it forms islands of cycling glandular tissue. An irregular or interrupted JZ on ultrasound should raise concern. The myometrial invasion of the endometrium is commonly asymmetric, resulting in an irregularly enlarged, soft and tender uterus.
Who Develops This Condition?
Adenomyosis appears to be more common in women with a history of early menarche, shorter cycles, endometriosis, or uterine surgery, such as cesarean section, dilation and curettage, or myomectomy. Multiparous women are more likely to be diagnosed, as well.
When Does It Occur?
In the past, the condition was most commonly diagnosed in women in their 40s and 50s, but this may reflect the age at which women have a hysterectomy, rather than the age at which the condition is most prevalent.
Where Does It Occur?
Adenomyosis can occur anywhere in the uterus but seems to have a predilection for the posterior wall, according to a study published in the Journal of Nuclear Medicine titled "MRI and CT of the Female Pelvis." It can be generalized or focal, masquerading as a myoma. Doppler can help distinguish one from the other since the vessels run translesionally, rather than in a circular pattern as with myomas. This is an important distinction because adenomyosis lacks a pseudo capsule, making surgical excision incomplete and difficult in most cases.
Why Do We Care About This Diagnosis?
This diagnosis is important because it enables us to counsel and treat our patients successfully. The hallmark symptoms of adenomyosis are dysmenorrhea, menorrhagia and chronic pelvic pain, and it often coexists with endometriosis and uterine fibroids. In vitro fertilization (IVF) literature has also linked the condition to decreased fertility.
The International Federation of Gynecology and Obstetrics PALM-COEIN classification of abnormal uterine bleeding ranks adenomyosis as one of the leading structural causes of bleeding that has a significant impact on women's lives. Symptomatic treatment includes anti-inflammatory medications and hormonal manipulation, such as a levonorgestrel intrauterine device, to stop menses and, on occasion, surgical treatment. Hysterectomy and other procedures, such as excision, ablation, uterine artery embolization (UAE) and destruction with magnetic-guided ultrasound, have also been explored.
How to Spot Symptoms With Adenomyosis Ultrasound
A consensus statement from the Morphological Uterus Sonographic Assessment group asserted that the presence of two of the following ultrasound criteria indicates a diagnosis of adenomyosis:
- Asymmetrical thickening greater than 1.5 cm
- Heterogenous myometrium
- Myometrial cysts
- Hyperechoic islands
- Fan-shaped shadowing
- Echogenic subendometrial lines
Diffuse AM on adenomyosis ultrasound
This benign but potentially debilitating gynecologic disorder deserves more study, earlier diagnosis and better tools for management. An astute clinician will make the adenomyosis diagnosis via ultrasound in the office, and scientific studies will determine appropriate therapeutic intervention.
