Technology Description:
The design comprises an ultrasound transducer enclosed in a flexible sealed bag containing acoustic coupling fluid for endoscopic ultrasound (EUS). The sealed bag contains a constant volume of coupling fluid that improves acoustical contact resulting in superior imaging.
Within the bag, the probe achieves good acoustical coupling on irregular surfaces and stays flush with surfaces, even if the transducer is not parallel to the surface. The design permits the operator to change the shape of the bag at will from a long, slender bag for passing through the biopsy channel to a short, fat bag for imaging. Expanding the bag to a larger diameter provides the needed acoustic stand-off for imaging the mucosa layer.
Background:
To obtain good ultrasound imaging, there must be good acoustical coupling - no air gaps - between the transducer and the tissue. Good coupling can be difficult to achieve when the surfaces of interest are curved or irregular.
For external imaging, the operator applies acoustical gels and maneuvers the transducer manually. In EUS, good coupling is more difficult to achieve because the operator cannot apply acoustical gels internally and can only manipulate the probe indirectly.
Whereas some EUS techniques rely on using inflatable balloons or applying water to the imaging surface, such methods are susceptible to interfering air bubbles and require additional channels in the insertion tube. In addition, contact by water immersion cannot be used in gastrointestinal applications and does not work when the water disperses.

Advantages of the flexible sealed bag design:
Technology Offer:
The Washington Research Foundation is seeking commercial partners to develop the technology. License or option arrangements are
negotiable. US rights to the technology are available.
Patents/Publications:
U.S. Patent No. 5,178,150 claims a miniature ultrasound imaging probe that incorporates a transducer enclosed within a flexible sealed bag. Washington Research Foundation is managing the rights under this patent.
For additional information, please contact:
Beth G. Etscheid, Ph.D.
Director of Licensing
Washington Research Foundation
2815 Eastlake Avenue E, Suite 300
Seattle, WA 98102
Tel: 206.336.5600
Fax: 206.336.5615
betschei@wrfseattle.org