As a result, doctors will be better able to see the development of tumours and thus commence treatment earlier. In analogy to high-definition TV (HDTV), the new technology is known as High-Definition PET (HD•PET), and will be launched on the market early next year.
PET examinations are primarily used to detect and monitor cancerous growths and metastases. To conduct these examinations, the patient is injected with a very small dose of weakly radioactive liquid, which preferentially accumulates in cells with an elevated metabolic rate, from where it releases positrons. The patient is surrounded by a ring of detectors that record the radiation emitted by the positrons, enabling the system to display tumour cells on the basis of their metabolism.
During the examination, the detectors record all of the positrons in the scan area. This has the drawback that the farther an object is from the scanner's central axis, the fuzzier the image becomes. As a result, small metastases in particular are very hard or impossible to recognise if they are far from the central axis and the tumour's stage of development therefore becomes difficult to ascertain.
HD•PET uses sophisticated algorithms to correct fuzzy areas and show images on monitors at a steady level of resolution. The increased resolution also improves the visual contrast provided by the PET system, so that the signal-to-noise ratio is doubled and images become sharper. With the new system, oncologists can recognise not only tiny metastases throughout the image, but also better distinguish difficult to define lesions within the lymph nodes, as well as in the stomach, head, neck and brain.
As a result, doctors will be able to determine earlier and more precisely how patients should be treated, whether they should be operated on or undergo radiation or chemotherapy. After treatment, the system's improved resolution will make it possible to determine early on if there is a recurrence of small tumours in the head or neck.
Further information can be found under: http://www.siemens.com/medical
Enquiries: Jose Machado
Siemens Southern Africa
Debra de Wet
Tel: (011) 676-2000
