GYN ultrasound

The plane, and which way is up

Transvaginal, sagittal: the probe is in the vagina, so the top of the screen is nearest the probe (the cervix and lower uterus), the fundus is deeper on the screen, and the bladder is at the upper left. Transabdominal sagittal is the reverse: the bladder is at the top of the screen and the uterus lies behind it. Then transverse. Describe the uterus by size, position (anteverted or retroverted), outline, myometrial texture, and the endometrium in its own words.

Look for, in order

1. The endometrium: thickness measured across both layers in the sagittal plane at its thickest, its echogenicity for the cycle phase, its outline, and any fluid or focal thickening in the cavity.
2. The myometrium: homogeneous, or with discrete masses (fibroids: well-defined, whorled, with shadowing) or diffuse change (adenomyosis: asymmetric thickening, cysts, striations, an ill-defined junctional zone).
3. For each fibroid: number, size, and position (submucosal, intramural, subserosal, pedunculated; FIGO type) because position decides symptoms and surgery.
4. The cervix and the pouch of Douglas.

What normal looks like

A uterus about 7 to 8 cm long in the reproductive years, smaller after the menopause; endometrium thin and linear after a period, thick and bright before it, and under 4 to 5 mm after the menopause.

Trap. A postmenopausal endometrium over 4 mm with bleeding needs tissue; without bleeding the threshold is different and the finding is more often benign.

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