Diagnostic Ultrasound - Abdomen and Pelvis

Polycystic Ovarian Syndrome
Diagnoses: Female Pelvis
TERMINOLOGY
• Complex heterogenous syndrome of ovulatory
dysfunction, menstrual irregularity, and androgen excess
• Rotterdam criteria for polycystic ovarian syndrome (PCOS)
developed in 2003: 2 of 3 criteria must be present
○ Oligo- or anovulation
○ Hyperandrogenism (clinical or biochemical)
○ Polycystic ovaries (by ultrasound)
IMAGING
• Enlarged ovaries with volume > 10 mL or ≥ 12 follicles per
ovary measuring 2-9 mm in diameter
• Calculate volume using formula for prolate ellipsoid
(longitudinal x transverse x AP diameter x 0.5233)
• Ovarian stromal ↑ echogenicity
• If dominant follicle (> 10 mm diameter) or corpus luteum
seen, repeat scan during next cycle to avoid false elevation
of volume
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Normal
○ Ovarian morphology alone is insufficient for diagnosis of
PCOS
○ PCOM seen in ~ 22% of women, PCOS prevalence is only
5-10%
• Suppressed ovary
• Other causes of hyperandrogenism
CLINICAL ISSUES
• Anovulation → oligo/amenorrhea
• Hyperandrogenism → hirsutism
• Obesity with associated hyperinsulinemia/insulin resistance
DIAGNOSTIC CHECKLIST
• Features seen in 1 ovary are sufficient to diagnose PCOS
(Left) Transvaginal US
demonstrates an enlarged
right ovary with a volume of
19 mL and multiple follicles
ſt between 2-9 mm in size in
a patient with polycystic
ovarian syndrome (PCOS).
Note the echogenic central
stroma st. (Right)
Transvaginal US demonstrates
a normal size ovary with a
volume < 10 mL. However,
Rotterdam criteria are met
because there are ≥ 12
follicles measuring between 2-
9 mL.
(Left) Transvaginal US
demonstrates the typical
appearance of polycystic
ovarian morphology with an
enlarged ovary containing
multiple small follicles st.
(Right) Color Doppler
longitudinal transvaginal US
shows the central stroma of
the ovary is well vascularized
, which is not a diagnostic
criterion but has been noted in
polycystic ovarian
morphology.
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