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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 ovarian cyst with a fine lace-like internal pattern, measured by calipersTransvaginal

GYN ultrasound · Adnexa

Sudden unilateral pelvic pain mid-cycle

Diagnosis

Haemorrhagic ovarian cyst

Normal against abnormal

The plane, and which way is up

Transvaginal, each adnexa found by following the tube laterally from the cornu or by the ovary's relation to the iliac vessels; the ovary is identified by its follicles.

Look for, in order

  1. Is the mass ovarian (the ovary cannot be seen separately) or extra-ovarian (the ovary is seen beside it)?
  2. Describe it, do not name it: unilocular or multilocular, cystic or solid or mixed, the wall, the septa, any papillary projections, the echogenicity of the fluid (clear, ground-glass, fat with hair), acoustic shadowing, and flow on Doppler.
  3. Size in three planes; free fluid; the other side.
  4. Then apply a rule (the IOTA simple rules or O-RADS) to sort benign from suspicious.

What normal looks like

A simple cyst under 5 cm in a premenopausal woman is a functional cyst and needs no follow-up. Ground-glass fluid means an endometrioma; fat, hair and a bright plug mean a dermoid; a tubular structure with incomplete septa is a hydrosalpinx.

Trap. A haemorrhagic corpus luteum can look solid and worrying for a few weeks; the clot has no flow and the mass shrinks on the repeat scan.

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

  • A unilocular ovarian cyst with a fine reticular (lace-like) internal pattern of fibrin strands
  • No internal flow on Doppler (not shown)

What it means for the patient

A haemorrhagic corpus luteum is a common cause of acute pelvic pain. The lace-like fibrin pattern, or a retracting clot with a concave edge, is characteristic. Management is analgesia and a repeat scan in 6 to 12 weeks: it resolves. The important differentials are torsion (a painful, enlarged, oedematous ovary) and ectopic pregnancy (a pregnancy test on every patient with pelvic pain).

Framework: SOGC, Guideline: endometriosis diagnosis and management (2024).

OBGynSpace Tutor

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