Finding cancer at an early stage

29.02.2008

New ultrasound technology will make it possible for doctors to discover cancer tumors far earlier than before.

A method that transmits new and more advanced ultrasound signals is being tested in Trondheim. The chances of discovering and diagnosing tumors in the prostate and breast will improve significantly.

- The first clinical testing has been done, and the results so far are promising, says Rune Hansen. He is a researcher at Norwegian University of Science and Technology (NTNU) and at SINTEF Health Research.

A veil of noise

The ultrasound images that are processed using current methods are often strongly hampered by a kind of noise that originates from sound signals that move back and forth between reflectors that are dissimilar in strength. This is called ‘multiple echo’ or ‘reverberations’ in technical terms. This is particularly a problem when the signal is being sent through the ‘body wall’ in order to image internal organs in the body.

The sound signals will ricochet back and forth between layers of fat, muscles and connective tissue in the body wall, and this results in misty ultrasound images.

The new method that is being processed is far more detailed, and it will be possible to separate details in parts of the body such as the liver, prostate and breast. This makes it easier to discover changes in body tissue, and he chance of discovering cancer tumors at an early stage will increase significantly.

Detailed images

In addition to giving a more detailed images of body tissue, the new ultrasound method is also much better at discovering and reading contrast agents. Such liquid is given intravenously and this makes perfusion imaging possible in organs that are suspected being cancerous.

- Tumors generate their own veins in order to obtain sufficient oxygen and nutrients so they are able to grow. This method has the potential to discover these changes in micro circulation much earlier than at present, says RuneHansen.

Three forms of cancer where the new method will make it possible to discover cancers at an earlier stage are prostate, breast and thyroid gland cancers. Another area of application is diagnoses of cardiovascular diseases like heart diseases and plaque/stenoses/anurism in large arteries.

Transmission in two signals

The newly developed method has been given the name ‘SURF imaging’ – Second order UltRasound Field imaging.

When one applyes the traditional method, an imaging pulse is inserted, and the subsequent ‘echo’ that is heard is the basis of the ultrasound image. The important new factor is that the imaging pulse is accompanied by another signal.

Rune Hansen is a part of a team under Professor Bjørn Angelsen, who is one of the pioneers in ultrasound research in Trondheim. Professor Angelsen assumes that the method will be ready for normal use on the first patients in about a year’s time.

By Tore Oksholen/Gemini