Diagnostic Ultrasound - Abdomen and Pelvis

Hematometrocolpos
TERMINOLOGY
Abbreviations
• Hematometra (HM)
• Hematocolpos (HC)
• Müllerian duct anomaly (MDA)
• Cloacal malformation (CM)
Definitions
• HM: Distension of uterine cavity by blood products
• HC: Distension of vagina by blood products
• Hematometrocolpos: Distension of uterus and vagina by
accumulated blood
IMAGING
General Features
• Best diagnostic clue
○ Echogenic fluid within distended uterus ± vagina
Ultrasonographic Findings
• Grayscale ultrasound
○ Distended uterine &/or vaginal cavities
– HM appears thick-walled due to surrounding
myometrium
– HC is lower in pelvis and appears thin-walled
compared to HM
○ Mixed echogenicity material within uterine &/or vaginal
cavities
– Blood products of varying age
○ Fetal diagnosis reported
– Thin bulging membrane separating labia
– Distended vagina
– May be associated with ascites attributed to uterine
reflux via fallopian tubes versus associated distal
urinary obstruction
• Color Doppler
○ No flow: Presence of flow should raise concern for mass
• 3D allows better sonographic evaluation of uterine fundal
contour
○ Vital for diagnosis of MDA
MR Findings
• Distended uterus &/or vaginal cavities
○ T1WI: Isointense to hyperintense material
○ T2WI: Hyperintense, but less than simple fluid
• T1 C+: No enhancement of endometrial/vaginal contents
CT Findings
• Nonspecific: Requires further work-up with US or MR
• Enlarged distended uterus
○ May mimic a fluid collection, distended rectum, or mass
Imaging Recommendations
• Best imaging tool
○ US for initial evaluation or to confirm CT findings
○ MR best to confirm blood products, absence of solid
mass
○ MR best to clarify anatomy, relationship of pelvic organs
• Protocol advice
○ Ultrasound
– Consider use of translabial scans
– Some reports of transrectal sonography
○ MR
– Include renal images on coronal scout views
– True coronal images of uterus to evaluate fundal
contour for MDA
– Distend vagina with Surgilube if possible, helpful to
inject even if tiny perineal orifice
– Contrast necessary if there is concern for an
underlying mass
DIFFERENTIAL DIAGNOSIS
Pyometra
• Associated with fever, elevated white cell count
• Clinical diagnosis, imaging cannot distinguish pus vs. blood
• Does not involve vagina
Endometritis
• Seen after childbirth, uterine instrumentation
• Look for gas bubbles within endometrial cavity
• Not associated with amenorrhea
• Does not involve vagina
Muco/Hydrometrocolpos
• Uterus/vagina distended with mucous secretions, not blood
• Most commonly associated with imperforate hymen
• Hymenal membrane appears white
○ HC/HM hymenal membrane appears bluish due to
accumulated blood products
Gestational Trophoblastic Disease
• Uterus distended by complete mole, has typical snowstorm
appearance, not echogenic fluid
• Invasive mole typically hypervascular mass invading
myometrium
○ Myometrium may be thinned in HM but is intact
• Does not involve vagina
Retained Products of Conception
• History of recent delivery
• Solid perfused tissue
• Retained clot is hypoechoic, nonvascular, smaller in volume
than that seen with HM
• Does not involve vagina
Complex Adnexal Mass
• Always identify organ of origin of adnexal mass
○ Most are ovarian: Normal uterus can be identified
separately
○ Pedunculated fibroids with cystic degeneration can be
confusing
– Not associated with amenorrhea
– Look for vessels from myometrium to mass
– Often other fibroids in uterine corpus in addition to
pedunculated
○ If normal uterus is not identified could "mass" be
abnormal uterus?
• May require MR to visualize normal ovaries
○ If large complex pelvic mass
○ If vaginal sonography not possible
Diagnoses: Female Pelvis
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