MODEL-SCANNER VALIDATION FOR INVERSE SCATTER IMAGING

TECHNISCAN, INC. PROPOSES TO TEST THE EFFECTIVENESS OF A NEWULTRASOUND IMAGING METHOD FOR THE DETECTION AND SCREENING OFBREAST CANCER WITH REAL DATA OBTAINED FROM A SCALED-DOWN, WORKING, SCANNER MODEL FEATURING AN ELECTRONICALLY SCANNED TRANSDUCER ARRAY. THE COMPLETE TRANSDUCER ARRAY WILL BE A REGULAR POLYGON CONSTRUCTED FROM FOUR OR SIX TRANSDUCER ARRAYS, EACH WITH 128 ELEMENTS. MULTIPLE TRANSMITTING AND RECEIVING MULTIPLEXER BANKS WILL ALLOW STRONG INCIDENT FIELDS TO BE PRODUCED AND PERMIT RAPID DATA ACQUISITION. THIS DESIGN ALSO PROVIDES HIGH STABILITY AND FREEDOM FROM VIBRATION FOR THE JITTER- AND DRIFTFREE DATA REQUIRED FOR USE IN VERY ACCURATE INVERSE-SCATTERING IMAGING ALGORITHMS. THESE ALGORITHMS ARE BASED UPON COMPUTING THE INVERSE-SCATTERING SOLUTION TO THE EXACT (NOT LINEARIZED) INHOMOGENEOUS HELMHOLTZ WAVE EQUATION. THIS SOLUTION PROVIDES SEPARATE AND INDEPENDENT IMAGES OF DENSITY (RHO), COMPRESSIBILITY (KAPPA), AND ABSORPTION (ALPHA). THE SPATIAL RESOLUTION OF EACH OF THESE THREE IMAGES IS EXTREMELY HIGH, NEAR 250 MICRONS OR 1/2 WAVELENGTH AT 3 MHZ.SAMPLES OF BREAST CANCER TISSUE, BENIGN TUMORS, AND OTHER TISSUES WILL BE SCANNED. THIS PROOF OF CONCEPT WILL LEAD TOCONSTRUCTION OF A FULL-SCALE SCANNER FOR PHASE II CLINICAL TRIALS.