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GYN ultrasound

17 studies9 challenges

Describe the uterus, the endometrium and each adnexa before naming anything. Every image opens with how to read it; switch to Practice when you are ready to be tested.

Transvaginal ultrasound of an enlarged ovary containing many small peripheral follicles around a dense centreTransvaginal

GYN ultrasound · Ovaries

Oligomenorrhoea and hirsutism, ovarian scan

Diagnosis

Polycystic ovarian morphology

Normal against abnormal

The plane, and which way is up

Transvaginal in two planes, the ovary measured in three dimensions for its volume, the follicles counted around its periphery.

Look for, in order

  1. Volume (length by width by height by 0.523).
  2. Follicle number: count the antral follicles of 2 to 9 mm.
  3. The stroma: is it increased and bright, with the follicles pushed to the edge?
  4. A dominant follicle or a corpus luteum, which tells you the cycle phase.

What normal looks like

Polycystic morphology is 20 or more follicles per ovary or a volume of 10 mL or more on a modern probe; it is one Rotterdam criterion, not a diagnosis, and is common in normal adolescents.

Trap. Ultrasound is not used to diagnose PCOS within 8 years of menarche, because a multifollicular ovary is normal then.

Describe it in this order

  1. The plane and the approach
  2. Uterus: size, position, outline, myometrium
  3. Endometrium: thickness, echogenicity, outline, cavity contents
  4. Cervix
  5. Right adnexa, then left: ovary seen, any mass described not named
  6. Pouch of Douglas: free fluid
  7. Then, and only then, the impression

Findings

  • An enlarged ovary
  • Many small follicles of similar size arranged around the periphery
  • Increased central stroma

What it means for the patient

Polycystic ovarian morphology is one of three criteria (with oligo-anovulation and hyperandrogenism); two of three make the diagnosis of PCOS once other causes are excluded. Morphology alone is not PCOS: it is found in many women with normal cycles, and it is not used as a criterion in adolescents, in whom multi-follicular ovaries are normal.

Framework: International PCOS Network, International evidence-based guideline for the assessment and management of polycystic ovary syndrome (2023).

OBGynSpace Tutor

It coaches the description; it does not read the image for you and will not name the diagnosis before you commit.