Title :
Field conjugate acoustic lenses for ultrasound hyperthermia
Author :
Lalonde, Ronald J. ; Worthington, Arthur ; Hunt, John W.
Author_Institution :
Dept. of Med. Biophys., Toronto Univ., Ont., Canada
Abstract :
Multipoint foci have been synthesized by applying the pseudoinverse field conjugation method to a single ultrasonic transducer coupled to a polystyrene lens. The lens design is based on phased array calculations are then fabricated on a computer-controlled milling machine. The measured beam patterns from the lenses agree closely with the beam patterns predicted by theory for the equivalent phased arrays. Temperature distributions from thermal modeling and those measured in tissue equivalent phantoms show that the lens system is capable of generating strongly localized, controlled temperature fields for hyperthermia.<>
Keywords :
acoustic imaging; biomedical ultrasonics; biothermics; radiation therapy; temperature distribution; thermal analysis; ultrasonic devices; US device; acoustic lenses; beam patterns; computer-controlled milling machine; controlled temperature fields; localized fields; phased array calculations; polystyrene lens; pseudoinverse field conjugation method; thermal modeling; tissue equivalent phantoms; ultrasonic transducer; ultrasound hyperthermia; Acoustic beams; Acoustic measurements; Hyperthermia; Lenses; Metalworking machines; Optical design; Phased arrays; Temperature distribution; Ultrasonic imaging; Ultrasonic transducers;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on