Ultrasound
Ultrasound (US, also called “sonography”) is an imaging technique where very high frequency sound is used to build up an image of soft tissues beneath the probe. The principle is very similar to that of sonar or depth sounders used by boats.
The Radiologist will apply some jelly to the part being scanned which allows the ultrasound beam to penetrate through the skin and create the image. Ultrasound is a “real time” imaging modality, where movement is seen in real time on the screen.
- Abdominal ultrasound imaging:
- Ultrasound is used as a first line imaging modality for a large number of abdominal conditions. Typically it is used at the start of the diagnostic pathway for abdominal pain and is very good at looking at the liver, gallbladder (for gallstones) as well as the kidneys and often the pancreas. It is very good at identifying abnormal fluid collections (e.g., abscesses) and is useful for looking at blood vessels.
- Pelvic ultrasound imaging
- Pelvic ultrasound is the imaging method of choice for looking at gynaecological problems. The patient will usually be scanned with a full bladder, the bladder is used as a window to see through to the pelvis, and then if appropriate the Radiologist will scan the patient with an empty bladder using a special transvaginal probe. This allows a very detailed picture to be built up of the uterus (e.g., looking for fibroids and also looking at the detail of the lining of the uterus, the endometrium) as well as looking at the ovaries in detail.
- In men, ultrasound is very useful at looking at the prostate and the bladder.
- Vascular ultrasound
- Ultrasound can be used to look at blood vessels. Using a technique called Doppler, blood flow can be analysed. This is particularly useful for looking at abnormal dilatation of some vessels (e.g., the aortic aneurysms in the abdomen) but also for looking at narrowing (stenosis) of blood vessels in the neck (the carotid arteries). It is very important to identify carotid artery stenosis in selected patients as they are at high risk of strokes.
- Superficial and Small Parts Ultrasound
- Extra-high frequency ultrasound scanning produces exquisitely detailed images of lymph nodes, the thyroid gland, the salivary glands and, in men, the testicles. This is the optimal way of detecting abnormalities in these organs, particularly small tumours that cannot be felt. Patients are often referred either if a small lump is felt, or as a screening tool. Ultrasound is also useful for guiding biopsy of small lumps in a minimally invasive way.
General ultrasound is performed by all Radiologists in the Group. Four Radiologists also perform transvaginal scanning (Dr Wetton, Dr Ignotus, Dr Kirwan and Dr Tallett). Doppler ultrasound scanning of the carotid arteries is also performed by Dr Ignotus, Dr Wetton and Dr Tallett. Dr.Garrett specialises in Musculoskeletal Ultrasound and Dr Conry performs ultrasound guided biopsy of the Head and Neck region.
Preparation
Ultrasound scanning of the small parts requires no preparation. Ultrasound scanning of the abdomen will normally require the patient to be fasted. Ultrasound scanning of the pelvis requires a full bladder and patients will be instructed to drink a moderate volume of water so that they have a relatively full bladder.
Risks
At the power levels used for diagnostic ultrasound, no identifiable risks are present.
