Trans abdominal ultrasound
Use the full urinary bladder as an acoustic window to angle across to the ovary.
Axial trans-abdominal ultrasound image with the ovary lateral to the uterus.
Trans vaginal ultrasound
Axial trans-vaginal ultrasound image.
Axial trans-vaginal scan plane.
Reposition the probe into the fornix to angle towards the adnexum.
Ultrasound of Normal transvaginal ovary demonstration normal peripheral follicles.
Ultrasound of The uterus may be oblique and squash the ovary giving it a flattened ovoid shape.
The postmenopausal ovary can be difficult to identify because of the absence of follicles and the reduced size.
The paediatric ovary will have multiple small follicles.
Role of Ultrasound
- To examine the uterus, ovaries cervix vagina and adnexae.
- Classification of a mass identified on other modalities eg solid, cystic, mixed.
- Post surgical complications eg abscess, oedema.
- Guidance of injections, aspiration or biopsy.
- Assistance with IVF.
- To identify the relationship of normal anatomy and pathology to each other.
- P/V bleeding/discharge
- Irregular periods
- Pelvic pain
- F/H uterine or ovarian Cancer
- Palpable lump
- Infertility- primary or secondary
- Transvaginal scanning is contra-indicated if the patient is not yet sexually active,or cannot provide informed consent.
- Large patient habitus will reduce detail, particularly via the transabdominal approach.
- Excessive bowel gas can obscure the ovaries.
- If possible, scan the patient in the first 10 days of the cycle. Preferably Day 5-10 for improved diagnostic accuracy in the assessment of the endometrium and ovaries.
- A full bladder is required . Instruct the patient to drink 1 Litre of water to be finished 1 hour prior to their appointment. They cannot empty their bladder until after the scan.
- Use the highest frequency probe possible which gives adequate depth. Commonly a curvilinear 3-6Mhz probe and a 6-10Mhz endovaginal probe. Low dynamic range.
- A linear 5-12MHz probe for Paediatric patients or an ovary lying superficially.
- Gartners duct or Bartholin cyst
- Vaginal carcinoma
- Hydro/haematocolpos (secndary to imperforate hymen or vaginal stenosis)
- Foreign body
- Nabothian (retention) cysts
- Cervical fibroids
- Cervical carcinoma
- Cervical stenosis
- Fibroids (leiomyoma)
- Endometrial Polyps
- Endometrial Carcinoma
- Endomtrial hyperplasia
- Cystic hyperplasia 2ndary to Tamoxifen
- Adhesions- Ashermans Syndrome
- Submucosal fibroids
- Arterio-venous malformation (AVM)
- blood/fluid/infection or retained produts of conception (RPOC)
- Ovarian cysts
- simple Vs complex (haemorrhagic, corpus luteal, ruptured, septated).
- any mural nodules
- Ovarian tumours:
- Cystadenoma (serous/mucinous)-Benign
- Cystadenocarcinoma (serous/mucinous)-Malignant
- Polycystic Ovarian Disease
- Hyperstimulation syndrome
- Ectopic pregnancy
POUCH OF DOUGLAS (POD) & ADNEXAE
- Pelvic inflammatory disease-PID (may be indicated by above conditions)
- Cysts (Mesenteric)
- Ectopic pregnancy
- Pelvic venous congestion
- Ecopic pregnancy
- Ectopic pregnancy
Bladder and Bowel should also be examined.
This is a generalised overview to identify the cervix, uterus and ovaries.
- Check for the orientation the uterus (anteverted V’s retroverted)
- Assess the myometrium
- Assess the endometrial status and measure the thickness: <10mm pre menopausal; <4mm post menopause or ,<6mm if post menopausal on HRT
- Look for free fluid in the pouch of douglas
- Check the ovaries and adnexae
- Assess bladder
Scan sagittally in the midline immediately above the pubis. In this plane you should be able to assess the uterus, vagina and cervix. Zoom the image to assess and measure the endometrial thickness. Rotate into transverse and angle slightly cranially to be perpendicular to the uterus. Whilst in transverse and slightly right of midline, angle left laterally to identify the left ovary using the full bladder as an acoustic window. Examine this ovary in two planes. Now repeat this for the right ovary.
TRANS-VAGINAL (TV) APPROACH
INSERTING THE TV PROBE
- Before letting the patient empty their bladder, show them the TV probe and explain the procedure. Indicate the length that is inserted which is approximately the length of a standard tampon. Explain there is no speculum used. Explain the importance of a TV scan because it is the gold standard in gynaecological ultrasound because of its superior accuracy and improved diagnostic resolution.
- Cover the probe with a latex free Transvaginal sheath and lubricate with sterile gel on the outside.
- Elevate the patients bottom on a thick sponge/pillow to assist the scan. A gynaecological ultrasound couch which drops down is ideal so that a better angulation is achieved for an anteverted uterus.
- Ensure the patient is ready and get permission before inserting the probe.
- If there is some resistance as the probe is being inserted, offer for the patient to help guide the probe in far enough to see the end of the fundus.
- Keep asking the patient if they are okay.
- When manouvering the probe to visualise the adnexae, withdraw slightly then angle the probe towards the fornix. This avoids unnecessary patient discomfort against the cervix.
Basic Hardcopy Imaging
An pelvic series should include the following minimum images;
- Uterus – longitudinal, transverse (with measurements)
- Endometrial thickness measured in the longitudinal plane
- Both ovaries- longitudinal, transverse (Volume)
- Colour flow/Doppler particularly in the case of torsion
- If assessing for infertility the number of follicles should be counted and any follicles which average >9mm with 2 measurements should be documented .
- Both adnexae
- Document the normal anatomy. Any pathology found in 2 planes, including measurements and any vascularity.