Multiwave Ultrasound Elastography Improves Breast Lesion Detection

A New MultiWave ultrasound technology has unique architecture that provides images in ultrasound-wave imaging or B-mode, as well as a new type of wave imaging, for precise, quantifiable, and reproducible real-time results.

SuperSonic Imagine (Aix-en-Provence, France) presented its ultrasound MultiWave technology at the European Congress of Radiology (ECR), held in March 2009 in Vienna, Austria. Aixplorer was designed for breast imaging professionals to improve their lesion diagnosis, and is the next generation of ultrasound machines. This technology is made possible through a close collaboration with the Laboratoire Ondes et Acoustiques of the ESPCI/CNRS (Ecole Supérieure de Physique et de Chimie Industrielles/Centre National de la Recherche Scientifique; Paris, France), Artann Labs (acoustic radiation; West Trenton, NJ, USA), and other patents and submissions directly registered by SuperSonic Imagine.

Since April 2008, clinical trials have been testing this technology with prototypes situated in 18 sites around the world; seven in the United States and 11 in Europe: UK, France, Italy, and Germany.

Aixplorer uses technology called SonicTouch to create low-frequency shear waves in the body through several focalized beams of acoustic energy. This acoustic energy is safe and can be highly localized allowing it to be projected to a specific area of the body.

Using the unique architecture of SonicSoftware, the Aixplorer can produce shear waves in the tissue and simultaneously image and quantify the motion of these waves, producing real-time results.

UltrafastImaging is a groundbreaking technology that captures shear wave propagation movement in tissue that was undetectable up until now. To capture a shear wave, acquisition rates must be at least 5,000 Hz. Aixplorer functions at speeds of up to 20,000 Hz while standard acquisition speeds of conventional ultrasound are approximately 100 Hz. By measuring the speed of the propagation of the shear waves, Aixplorer produces a quantifiable measurement of tissue elasticity (given in kilopascals), which can aid in the diagnostic process, as tissue elasticity can be related to pathology. Aixplorer produces an image called an elastography map, which shows the elasticity or stiffness in tissue by color. In general, the stiffer a tissue is the more likely it is to be linked to the development of fibrous tissue around the focal point of cancer.

Shear waves (also known as S-waves or secondary waves) are sound waves whose particles move at right angles to the direction of the wave. Shear waves are completely harmless and occur naturally in the body; a beating heart produces shear waves, for example. These waves can only travel through solid tissue. As shear waves travel through the body they are altered by changes in tissue stiffness. If a shear wave passes through stiffer tissue, the propagation speed increases. The speed of the propagation of a shear wave in tissue is directly related to tissue elasticity (Young's Modulus). The elasticity of tissue can be related to pathology findings of benign or malignant tissue.

Aixplorer is used in the same manner a conventional ultrasound system is used. For breast scanning, the patient will sit or lie down and have a gel applied to the localized area. The gel helps the transducer transfer the ultrasound waves through the body. The technician/sonographer or physician will then run the handheld transducer over the area to be imaged. A black and white image of the tissue will be displayed on the monitor. Using the ShearWave Elastography mode, the operator can have real-time quantitative information in kPa on the tissue elasticity and a visual realization of the tissue elasticity with a color map.

To improve the human/machine interaction, scientists from SuperSonic Imagine have adapted the manageability of video games to medical imaging through a large interactive touch screen. The Aixplorer is a noninvasive multiwave ultrasound system that quantifies true tissue elasticity while providing impeccable images and sophisticated features all packaged in an ergonomic design, to assist in the breast imaging diagnostic process. Aixplorer's ShearWave Elastography gives the physician an added tool to make a better diagnosis. The Aixplorer system is user-skill independent and provides reproducible results, giving healthcare professionals and patients more confidence in diagnosis.

Aixplorer was named after its birthplace, Aix-en-Provence, in France and is patented by SuperSonic Imagine.

Related Links:
SuperSonic Imagine
ESPCI/CNRS