MRI for adenomyosis: a pictorial review
Received: 31 May 2017 /Revised: 26 August 2017 /Accepted: 5 September 2017 / Published online: 4 October 2017
The Author(s) 2017. This article is an open access publication
Adenomyosis is defined as the presence of ectopic endome-
trial glands and stroma within the myometrium. It is a disease
of the inner myometrium and results from infiltration of the
basal endometrium into the underlying myometrium.
Transvaginal ultrasonography (TVUS) and magnetic reso-
nance imaging (MRI) are the main radiologic tools for this
condition. A thickness of the junctional zone of at least
12 mm is the most frequent MRI criterion in establishing the
presence of adenomyosis. Adenomyosis can appear as a dif-
fuse or focal form. Adenomyosis is often associated with
hormone-dependent lesions such as leiomyoma, deep pelvic
endometriosis and endometrial hyperplasia/polyps. Herein,
we illustrate the MRI findings of adenomyosis and associated
conditions, focusing on their imaging pitfalls.
• Adenomyosis is defined as the presence of ectopic endome-
trium within the myometrium.
• MRI is an accurate tool for the diagnosis of adenomyosis
and associated conditions.
• Adenomyosis can be diffuse or focal.
• The most established MRI finding is thickening of junctional
zone exceeding 12 mm.
• High-signal intensity myometrial foci on T2- or T1-weighted
images are also characteristic.
Keywords Adenomyosis ·Uterus ·Female urogenital diseases
· Magnetic resonance imaging · Diagnostic imaging
Adenomyosis is a common benign gynaecological disorder
defined as the presence of ectopic endometrial glands and
stroma within the myometrium . It is a disease of the
archimetra or inner myometrium and results from infiltration
of the basal endometrium into the underlying myometrium,
with subsequent hypertrophy and hyperplasia of smooth mus-
It is difficult to accurately determinate the incidence of
adenomyosis since the diagnosis can only be made with cer-
tainty by microscopic examination of the uterus. Although
generally estimated to affect 20% of women, the incidence
was approximately 65% in one study in which meticulous
histopathological analysis of multiple myometrial sections
was performed .
The mean frequency of adenomyosis at hysterectomy is
between 20% and 30% .
The aetiology of adenomyosis is still not fully understood
and various theories have been proposed. Exposure to
oestrogen , parity , and prior uterine surgery are
known risk factors. The most consensual theories propose that
adenomyosis results from invagination of the endometrial
basalis layer into the myometrium orfromembryological-
ly misplaced pluripotent Müllerian remnants .
Histopathological examination allows direct visualisation
of endometrial tissue inside the myometrium. Criteria for the
histologic diagnosis of adenomyosis include the presence of
penetrating glands at least: one low-power field from the
endo-myometrial junction, 2.5 mm below the basal layer of
endometrium or deeper than 25% of overall myometrial
* Lisa Agostinho
Department of Radiology, Hospital Beatriz Angelo, Loures, Portugal
Department of Gyneacology, Hospital da Luz, Lisbon, Portugal
Department of Radiology, Hospital da Luz, Lisbon, Portugal
Insights Imaging (2017) 8:549–556