Ultrasound machines were once the size of washing machines and used solely by radiologists and sonographers working in radiology departments. But in the past 10 years they have become cheaper, smaller, and more portable—the latest models are even pocket sized.

As a result ultrasound machines are increasingly used by non-radiologists as part of the clinical examination or to assist in practical procedures such as insertion of a central line. The number of general practitioners buying their own ultrasound machines has also gradually increased. So is this good or bad news for patients?

Gill Markham, vice president of the Royal College of Radiologists, says: “The price of an ultrasound machine has come down enormously to £5000-£10 000 [€6000-€12 000; $10 000-$20 000] and as a result they are used much more widely. Ultrasound has a reputation as a simple, easy test. It is easy to do but interpreting the results is not so easy and there are things that could be missed.”

Paul Allan, clinical director of radiology for Edinburgh, agrees: “There are people with very little training using ultrasound badly.” He says he is aware of surgeons doing ultrasound investigations for acute abdominal pain and mistaking invasive cancers for ruptured spleen.

The key issue is adequate training. As Dr Allan says, “I have no problem with who does ultrasound investigations, but they must be trained. Ultrasound does require experience and expertise. There is no physical risk to the patient but there is a risk of false negatives or false positives.”