Diagnostic Ultrasound - Abdomen and Pelvis

Extraovarian Adnexal Mass
Helpful Clues for Less Common Diagnoses
• Bowel Loop
○ Gut signature and peristalsis
• Appendicitis
○ Clinical features of infection, local pain, peritonism
○ Noncompressible blind ending tubular structure > 7 mm
diameter
○ Appendicolith may be visible
• Appendicular Mucocele
○ Pear-shaped or tubular mass arising from cecum
○ Wall calcification common
• Gastrointestinal Stromal Tumor (GIST)
○ Feeding vessels from mesentery or attached to bowel
• Lymphocele
○ History of nodal dissection
○ Extraperitoneal cysts flattened against pelvic sidewall
○ Surgical clips may be visible as echogenic foci
• Lymph Nodes
○ Malignant nodes can be anechoic and mistaken for cysts
○ Necrotic nodes can appear cystic (squamous cell
carcinoma or tuberculosis)
• Hematoma
○ Poorly defined hypoechoic mass with internal echoes
and complex septations
○ Consider in presence of corpus luteal cyst or ectopic
• Aneurysm
○ Tubular extraperitoneal structure in continuity with
vessels
○ May have crescentic echogenic mural thrombus
○ Doppler assessment confirms arterial flow
• Pelvic Varices
○ Multiple dilated veins in adnexa
○ Reversal of flow and increased caliber on Valsalva
○ May coexist with vulval or thigh varices
• Bladder Diverticulum
○ Demonstrable connection with bladder lumen
○ May be thick walled and contain debris
• Pelvic Kidney
○ Reniform morphology
○ Absent ipsilateral kidney elsewhere
• Perineural/Arachnoid Cyst
○ Simple cystic lesions related to sacral nerve roots
○ Communication with sacral foramina may be visible
Helpful Clues for Rare Diagnoses
• Isolated Tubal Torsion
○ Acute pain with previous tubal ligation, PID, hydrosalpinx
○ Dilated thick walled tubular mass medial to normal ovary
○ Sonographic whirlpool sign
• Müllerian Duct Anomaly
○ Accumulated blood products in non-communicating
rudimentary horn simulates adnexal mass
○ Stratified appearance of myometrium/endometrium
• Malignant Transformation of Endometrioma
○ As for endometrioma but with solid nodular components
• Tubal Carcinoma
○ Solid mass between uterus and ovary
○ Latzko triad of intermittent colicky pain and palpable
mass relieved by profuse vaginal discharge
• Tail Gut Cyst
○ Thin walled uni- or multilocular para-/retro-rectal cyst
○ Mucoid fluid with internal echoes
○ May be adherent to sacrum
• Endosalpingiosis
○ Multiple small cysts in relation to peritoneal surfaces of
pelvic viscera
• Actinomycosis
○ Prolonged placement of intrauterine device
○ Fibrotic thickening of pelvic peritoneum forms
hypoechoic mass-like lesions
○ May be associated with tubo-ovarian abscesses
SELECTED REFERENCES
1. Laing FC et al: US of the ovary and adnexa: to worry or not to worry?
Radiographics. 32(6):1621-39; discussion 1640-2, 2012
2. Moyle PL et al: Nonovarian cystic lesions of the pelvis. Radiographics.
30(4):921-38, 2010
3. Saksouk FA et al: Recognition of the ovaries and ovarian origin of pelvic
masses with CT. Radiographics. 24 Suppl 1:S133-46, 2004
Differential Diagnoses: Female Pelvis
Subserosal Leiomyoma/Broad Ligament
Fibroid
Subserosal Leiomyoma/Broad Ligament
Fibroid
(Left) Transvaginal ultrasound
demonstrates an ovoid mass
with a narrow base of
contact with the posterior
aspect of the retroverted
uterus ſt. The mass
representing an exophytic
fibroid has a heterogenous
texture. Other fibroids st are
seen with refractory shadows.
(Right) Transvaginal color
Doppler US demonstrates
multiple serpiginous feeding
vessels ſt coursing between
the mass (fibroid) and the
uterus st, confirming the
uterine origin of the mass.
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