You are in: eMedicine Specialties > Radiology > OBSTETRICS/GYNECOLOGY Uterus, AdenomyosisArticle Last Updated: Jul 2, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 8
  Author: Karen L Reuter, MD, FACR, Professor, Department of Radiology, Lahey Clinic Medical Center Karen L Reuter is a member of the following medical societies: American Association for Women Radiologists, American College of Radiology, American Institute of Ultrasound in Medicine, American Roentgen Ray Society, and Radiological Society of North America Editors: Harris L Cohen, MD, FACR, Vice Chairman/Associate Chairman (Research Activities), Director, Division of Body Imaging, Professor of Radiology, Stony Brook School of Medicine; Visiting Professor of Radiology, Johns Hopkins School of Medicine; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Spencer B Gay, MD, Professor of Radiology, Director of Body Computed Tomography, Department of Radiology, University of Virginia Health Sciences Center; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Consulting Staff, Department of Radiology, Virginia Mason Medical Center Author and Editor Disclosure Synonyms and related keywords: endometriosis, chronic bleeding, ectopic endometrium, heterotopic endometrial tissue, dysmenorrhea, menorrhagia, pelvic pain, infertility, intramyometrial cystic adenomyosis, adenomyoma, endometrial carcinoma INTRODUCTIONSection 2 of 8
  BackgroundAdenomyosis, although considered a variant of endometriosis, is different because of its behavior. Adenomyosis was first described by Rokitansky in 1860 and then clearly defined by Von Recklinghausen in 1896. It causes chronic bleeding unresponsive to hormonal therapy or uterine evacuation. In 1991, Sathyanarayana divided adenomyosis into 3 categories, depending on the location of the lesion. The classifications were as follows:
Iribarne and colleagues have suggested a new category: intramyometrial cystic adenomyosis.1 PathophysiologyPathologically, uterine adenomyosis is a condition in which the stroma and/or heterotopic endometrial glands are located more than 1 high-power field deeper than the endometrial-myometrial junction. The stratum basale of the endometrium gives rise to the heterotopic endometrial tissue. At histopathologic analysis, an adenomyoma is a described as a circumscribed, nodular aggregate of smooth muscle and endometrial glands, with compensatory hypertrophy of the myometrium surrounding the ectopic endometrium. FrequencyUnited StatesThe reported prevalence of adenomyosis in random hysterectomy specimens is 8.8-31% or 5-70%. Iatrogenic adenomyosis has occurred after laparoscopic myomectomy when the myometrium was not sutured in layers. AgeAdenomyosis affects premenopausal and perimenopausal women, usually those who are multiparous and older than 30 years. Clinical DetailsClinical signs and symptoms of adenomyosis include dysmenorrhea, menorrhagia, and pelvic pain. Other findings include chronic vaginal bleeding and unresponsiveness to hormonal therapy or uterine evacuation. Adenomyosis can cause infertility. Preferred ExaminationThe imaging diagnosis of adenomyosis is usually made by means of transvaginal ultrasonography (TVUS) or magnetic resonance imaging (MRI). Limitations of TechniquesThe imaging diagnosis of adenomyosis is usually made by using TVUS or MRI. Hysterosalpingography (HSG) and transabdominal ultrasonography (TAUS) often lack specificity for this diagnosis. The inability to resolve subtle differences in soft-tissue attenuation limits the usefulness of computed tomography (CT) scanning in diagnosing adenomyosis. DIFFERENTIALSSection 3 of 8
Endometrium, Carcinoma Other Problems to Be ConsideredAdenomatoid tumor MRISection 4 of 8
FindingsThe second modality commonly used for diagnosing adenomyosis, MRI, although more expensive than ultrasonography, can be employed in cases with indeterminate sonographic results or in patients who are undergoing uterine-sparing surgery for leiomyomas. Thin-section, high-resolution MRI scans obtained with a pelvic multicoil array are optimal for diagnosing adenomyosis. The uterine zonal anatomy is best seen on T2-weighted images. Variations in the normal thickness of the inner myometrium, or junctional zone, have been reported, with a mean thickness of 2-8 mm. Widening of this junctional zone has been associated with adenomyosis (see Image 3). Furthermore, the thickness of a normal junctional zone changes with the menstrual cycle, while the thickness of diffuse adenomyosis does not. However the MRI appearance of adenomyosis can change in response to hormonal stimulation and treatment. Findings from an MRI study of 20 healthy volunteers suggested that the upper limits of a normal junctional zone should be at least 7-8 mm to avoid a high false-positive rate in the diagnosis of adenomyosis. These authors noted that myometrial contractions can appear as adenomyosis. Haimovici and Tempany reported that a junctional zone of 12 mm or less is normal.2 They used findings of focal hyperintensity on T2-weighted images (see Image 3) to confirm the diagnosis of adenomyosis. These authors did not recommend the use of gadolinium enhancement to diagnose adenomyomas in their review article. In their review of the endovaginal ultrasonographic and MRI features of adenomyosis, Reinhold and colleagues concluded that adenomyosis could be diagnosed with a high degree of accuracy when the junctional zone thickness was 12 mm or greater.3, 4 A maximum thickness of 8 mm or less usually excluded the disease. When the maximum junctional zone diameter was 8-12 mm, secondary findings, such as high–signal-intensity foci on T1- or T2-weighted images, were necessary to make the diagnosis. The bright foci seen in the myometrium on T2-weighted images in 50% of patients (see Image 3) are islands of heterotopic endometrial tissue, cystic dilation of heterotopic glands, or hemorrhage. Whether the hemorrhage is from hormonal changes or from spontaneous causes is not known. Sometimes, linear striations of decreased signal intensity can be seen radiating out from the endometrium into the myometrium on T2-weighted images. These striations are the direct invasion of the basal endometrium into the myometrium. When the striations blend or become indistinct, pseudo-widening of the endometrium is seen. Focal adenomyosis, as opposed to diffuse adenomyosis, is seen as a localized, low–signal-intensity mass within the myometrium on both T2-weighted and contrast-enhanced T1-weighted MRIs. In one series of T1-weighted images, most of these masses were isointense relative to the surrounding myometrium. These focal adenomyomas were 2-7 cm in diameter, round or oval, and located in the posterior wall. They also had a poorly defined margin. In addition to depicting adenomyosis, MRI can be used to distinguish a focal adenomyoma from a leiomyoma. Adenomyomas lack distinct borders and any mass effect on both T2-weighted and contrast-enhanced T1-weighted MRI scans. Furthermore, most focal adenomyomas are in the posterior myometrium. Leiomyomas do not have this predilection. Both adenomyomas and leiomyomas have low signal intensity, although some leiomyomas with hemorrhage have high signal intensity. The most common lesion of adenomyosis seen on magnetic resonance images is a low–signal-intensity area on T2-weighted images that often gives the appearance of diffuse or focal widening of the junctional zone (see Image 3). This hypointense area is smooth-muscle hyperplasia accompanying the heterotopic endometrial glands. Gadolinium-based contrast agents (gadopentetate dimeglumine [Magnevist], gadobenate dimeglumine [MultiHance], gadodiamide [Omniscan], gadoversetamide [OptiMARK], gadoteridol [ProHance]) have recently been linked to the development of nephrogenic systemic fibrosis (NSF) or nephrogenic fibrosing dermopathy (NFD). For more information, see the eMedicine topic Nephrogenic Fibrosing Dermopathy. The disease has occurred in patients with moderate to end-stage renal disease after being given a gadolinium-based contrast agent to enhance MRI or magnetic resonance angiography (MRA) scans. As of late December 2006, the Food and Drug Administration (FDA) had received reports of 90 such cases. Worldwide, over 200 cases have been reported, according to the FDA. NSF/NFD is a debilitating and sometimes fatal disease. Characteristics include red or dark patches on the skin; burning, itching, swelling, hardening, and tightening of the skin; yellow spots on the whites of the eyes; joint stiffness with trouble moving or straightening the arms, hands, legs, or feet; pain deep in the hip bones or ribs; and muscle weakness. For more information, see the FDA Public Health Advisory or Medscape. Degree of ConfidenceThe reported accuracy of MRI for diagnosing adenomyosis is high. Its sensitivity and specificity are 80-100%, with an overall accuracy of 85-90.5%. ULTRASOUNDSection 5 of 8
FindingsThe gross ultrasonographic description of adenomyosis includes irregular, myometrial, cystic spaces predominantly involving the posterior uterine wall, an enlarged uterus with a widened posterior wall (see Image 1), an eccentric endometrial cavity, and decreased uterine echogenicity without lobulations, contour abnormality, or mass effects (which is more commonly seen with leiomyomas). Sonograms may also show an ill-defined margin between the normal myometrium and the abnormal myometrium, as well as an elliptically shaped myometrial abnormality. However, the occurrence of adenomyosis cannot be consistently differentiated from the presence of leiomyomas by using TAUS. Furthermore, heterotopic endometrium extending into the inner myometrium can appear as echogenic linear striations. When these lines are small or indistinct, pseudo-widening of the endometrium or poor delineation of the endomyometrial junctional zone is seen. Reinhold and colleagues reported from the literature that TAUS has a sensitivity of 80-86%, a specificity of 50-96%, and an overall accuracy of 68-86% in diagnosing adenomyosis.3, 4 From a series of 29 women with evidence of adenomyosis at hysterectomy, the morphologic criterion for adenomyosis at endovaginal ultrasonography was the presence of myometrial heterogeneous and hypoechoic areas with or without cysts. The sensitivity in that series was 86%, the specificity was 86%, and the positive and negative predictive values were 71% and 94%, respectively. Endovaginal ultrasonography, especially with a Doppler technique, can be used as the initial imaging modality to determine the presence of adenomyosis. It must be performed meticulously and with real-time imaging. Chiang and colleagues used color Doppler ultrasonography with the morphologic criteria to improve the diagnostic accuracy of ultrasonography in differentiating adenomyosis from leiomyomas.5 They found that 87% of the cases of adenomyosis had randomly scattered vessels or intratumoral signals. In 88% of leiomyoma cases, they observed peripheral scattered vessels or outer feeding vessels. In addition, in 82% of the adenomyomas, arteries within or around the uterine tumors had a pulsatility index (PI) greater than 1.17, and 84% of leiomyomas had a PI of 1.17 or less. On sonograms, the most common appearance of adenomyosis is areas of decreased echogenicity or heterogeneity in the myometrium. Specific details of this observation have been analyzed. The areas of decreased echogenicity are those where smooth-muscle hyperplasia has occurred. The areas of heterogeneity are small, echogenic islands of heterotopic endometrial tissues surrounded by hypoechoic smooth muscle. Dilated cystic glands or hemorrhagic foci within the heterotopic endometrial tissue cause the appearance of small myometrial cysts that are smaller than 5 mm in diameter. These are seen in about 50% of patients. INTERVENTIONSection 6 of 8
The treatment for symptomatic adenomyosis has been hysterectomy. The reported mortality and morbidity rates for this procedure are 1-2 deaths per 1000 cases and 25-50%, respectively. More conservative treatments are increasingly being used to treat adenomyosis. Gonadotropin-releasing hormone (GnRH) agonists have been used to treat the infertility that can result from adenomyosis. Adenomyosis has also responded to estrogen. Embolization with polyvinyl particles through the uterine arteries may decrease the size of leiomyomas, which are seen as vascular masses, and it may also relieve the signs or symptoms of adenomyosis. For example, uterine-artery embolization may relieve the heavy vaginal bleeding that patients with adenomyosis often experience. Kim and colleagues were able to relieve the symptoms in 3 patients with MRI and/or ultrasonographic findings of adenomyosis. Long-term follow-up analysis of these patients, including their fertility subsequent to the procedure, is being conducted. MULTIMEDIASection 7 of 8
REFERENCESSection 8 of 8
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