Diagnostic Ultrasound - Abdomen and Pelvis

Uterine Anomalies
Diagnoses: Female Pelvis
TERMINOLOGY
• Müllerian duct anomalies (MDA)
○ Series of uterine malformations resulting from abnormal
development, fusion, or resorption of müllerian ducts
• MDA types
○ Müllerian agenesis or hypoplasia
○ Unicornuate uterus
○ Uterus didelphys
○ Bicornuate uterus
○ Septate uterus
○ Arcuate uterus
IMAGING
• Best diagnostic clue: Abnormal configuration of
endometrial cavity ± abnormal external contour of uterus
• 3D ultrasound is vital for correct diagnosis
• MR to clarify anatomy, relationship of pelvic organs
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Imperforate hymen
• Cervical stenosis
• Pyometra
PATHOLOGY
• MDAs occur during 1 of 3 phases of development
○ Organogenesis phase: Uterine agenesis, hypoplasia,
unicornuate
○ Fusion phase: Didelphys, bicornuate
○ Septal resorption phase: Septate, arcuate
• Renal anomalies in ~ 30%
DIAGNOSTIC CHECKLIST
• Determining outer uterine contour is essential to
distinguish septate vs. bicornuate uterus
• Image renal fossae to assess for unilateral agenesis
(Left) Graphic of a septate
uterus shows minimal
indentation on the uterine
fundus . There is
myometrium in the superior
aspect of the septum,
although normal zonal
anatomy is not present in this
portion ſt. (Right) Transverse
ultrasound shows 2
endometrial cavities ſt
separated by myometrial
tissue . An early gestational
sac is present on the left
side. Evaluation of the
external uterine contour was
necessary to confirm this as a
septate uterus.
(Left) 3D ultrasound with
coronal MIP rendering shows a
muscular septum indenting
the fundal endometrium. The
coronal reconstruction readily
depicts the normal convex
outer uterine contour ſt of
this septate uterus. (Right) 3D
ultrasound with cut-surface
volume rendering shows a
deep muscular septum
extending into the fundal
endometrium, with a normal
convex outer uterine contour
ſt, consistent with septate
uterus.
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