Detailed echoes from inside the body

Medical diagnostic techniques using ultrasound are still progressing at an astonishing rate. A new high-resolution, all-digital system offers exceptionally versatile control of the shape of the scanner beam. It will be presented for the first time at the MEDTEC trade show (Stuttgart, March 18-20).

In the early days of medical ultrasound, physicians only saw shadowy outlines of the structures inside the body. Todays techniques are not only capable of providing still and moving images of very high resolution. They can be used to measure the rate of blood flow or even discern signs of hardening of the arteries: Where the walls of the blood vessels have lost their elasticity, the pulsating pressure of the blood only expands them to a minimal extent. The ability to detect changes in length of less than one millimeter in real time calls for extreme precision on the part of the ultrasound scanning head and electronics that process the echoed signals. In modern devices, the sound waves are not emitted in a simple conical beam - like a loudspeaker - but are focused and variably directed by the scanning head. The beam is reflected when it encounters tissue such as the wall of an artery, and the signals are echoed back to receiving sensors in the scanning head. Signal delay, intensity and direction are analyzed by the hard- and software, building finally up an image pixel by pixel and line by line, like a television picture.
How the ultrasound beam is shaped explains Peter Weber of the Fraunhofer Institute for Biomedical Engineering IBMT: The head contains an array of up to 256 piezoelectric elements which can be addressed individually and which oscillate in time with an applied AC voltage. If the frequencies and amplitudes are controlled dynamically and matched correctly, the individual sound waves are superimposed to form a directable beam less than one millimeter across. Weber and the members of his Ultrasound Systems Development research group have been working on a system that allows this beam to be shaped and directed with exceptional flexibility, producing images of unprecedented high resolution. The particularity of this Digital Phased Array System, or DiPhAS, lies in its hardware and software, which process all signals end to end in digital form, making them very precise and reproducible. The system is capable of recording up to 25 separate images per second. Stored data, such as those of a beating heart, can be retrieved at any time for later evaluation.
Engineer Weber and his team have already applied to have the system approved for use in medical diagnostics. DiPhAS will be making its public debut at the MEDTEC trade show in Stuttgart, from March 18 to 20. Visitors to Stand 617 in Hall 4 will be able to study the system more closely and gain a first-hand impression of its capabilities.,Contacts:,Dipl.-Ing. Peter Weber,Telefon: +49/ 68 94 / 9 80-2 27,Fax: +49/ 68 94 / 9 80-4 00,E-mail: [e-mail]
Fraunhofer-Institut fur Biomedizinische Technik IBMT,Ensheimer Stra?e 48,D-66386 St. Ingbert
Further information:,http://www.ibmt.fraunhofer.de/ibmt3ussystem_index.html (IBMT-Arbeitsgruppe Ultraschall- Systementwicklung)
Messe MEDTECH,

Pays

Germany