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Clinical Study Overview. Summary of Avera Clinical Status. Installed prototype systems at three leading U.S. clinical sites University of Washington Medical Center (installed 1999) Virginia Mason Medical Center (installed 2000) Johns Hopkins Medical Center (installed 2001)
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Summary of Avera Clinical Status • Installed prototype systems at three leading U.S. clinical sites • University of Washington Medical Center (installed 1999) • Virginia Mason Medical Center (installed 2000) • Johns Hopkins Medical Center (installed 2001) • Clinical studies focused on locating and characterizing lesions in patients screened with both mammography and ultrasound • Develop a lexicon of terminology compatible to BIRADs • Understanding basic sensitivity and specificity characteristics • Performed over 250 imaging procedures to date • Patient with BIRAD finding 0, 4,5, or other clinical symptom • Additional 7-10 units to be installed in 2003 • Includes UCLA Medical Center (Dr. Kalikali), Denver Imaging Associates (Dr. Stavros), Massachusetts General, MD Anderson • Several expanded trials planned
Clinical Trial Summary • University of Washington (1999-2001) • Dr. Connie Lehman • Early prototype • Funded by BCRP grant • Focused on image interpretation and imaging chain improvements • Resulted in publication (Academic Radiology ’00) • Status: Study completed
Clinical Trial Summary • Virginia Mason Medical Center (2001-present) • Dr. Beverly Hashimoto • Second generation prototype (OS-2000) • Two major upgrades implemented during trial • Focused on lesion detection and characterization • 169 patients imaged to date • Resulted in several abstracts and presentations (AIUM, RSNA, etc.) • Peer reviewed publication in progress • Status: Pilot study completed. Avera system installed and ready to begin patient imaging pending resolution of new contract requirements by VMMC. • Future work: Contrast IRB approved and ready to begin. Biopsy IRB pending.
Submitted for consideration to the American Institute of Ultrasound in Medicine (AIUM), 2003
Clinical Trial Summary • Johns Hopkins University (2001-2002) • Dr. Laurie Fajardo • Second generation prototype (OS-2000) • Same protocol as VMMC • 50 patients imaged • Results of study included in clinical data reports • Dr. Fajardo hired as department chair at University of Iowa • Status: Clinical trial halted at Hopkins due to loss of principal investigator. Dr. Fajardo has expressed interest in continuing trials at Iowa.
Ultrasound Contrast and DUS Attenuation Imaging Click for movie No image processing Frame subtraction Fluoroscopy-like imaging without the radiation Fundamental frequency (attenuation) imaging of DefinityTM injected into chicken breast
Ultrasound Contrast and DUS Harmonic Imaging No image processing Frame subtraction Contrast agent excited at fundamental frequency and imaged at the harmonic. Note that the contrast agent is now enhancing instead of attenuating.
DUS Contrast Summary • Combines structural and functional information • Contrast not destroyed mechanically as with reflective ultrasound but instead tied to physiological half-life • Could greatly increase specificity • Inherent image registration permits real-time processing of pre and post contrast image sets • Dual mode imaging permits both attenuation and harmonic imaging • Minimal operator training required • Large field of view • Clinical trials using DefinityTM ready to begin at VMMC
Computer Aided Diagnosis • Demonstrated benefit in Mammography • Difficult to implement in Ultrasound • small field of view • Speckle • operator dependency • imaging parameters • Ideal for Diffractive Ultrasound • Large field of view • Digital image capture • High spatial resolution and contrast sensitivity • Consistent image acquisition • Development underway with TRW • Promising preliminary results
To be presented as a poster at the Radiological Society of North America (RSNA), 2002
Ongoing Clinical Trials • Expand clinical trials to 7-10 US luminary sites in 2003 • 2003 clinical trial topics to include: • Double blinded multi-operator read of existing clinical data • Combinations of DUS alone, Mammo+DUS, Mammo+RUS • Results compared against truth data • Results published • Breast Ultrasound Contrast • IRB complete. Ready to begin clinical trials at VMMC • Biopsy • IRB in preparation at VMMC. No biopsies done to date as Avera system is required. • Computer Aided Diagnosis • Double blinded multi-operator read of existing clinical data utilizing CAD tools.