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The Imaging Sciences Ultrasound Department Experienced More Than This year’s annual report The Imaging Sciences summarizes progress from Ultrasound Department RCBU laboratories across experienced more than 5% diverse topics in biomedical growth in exam and patient ultrasound imaging and volumes in 2009; performing therapy. The cover and related over 20,000 exams. The stories inside this report unit continued to expand describe advances by RCBU its clinical coverage; adding members on novel applications more sonographer positions to of ultrasound for tissue manage the increased demand. engineering and regenerative In the spring of 2009, medicine. The RCBU continues GE’s newest platform, the Logic to advance the development of E9, was installed; replacing elastography techniques. Included within this report the existing Logic9 units. The new machines provide are highlights of innovations in sonoelastography and enhanced image quality and improved workflow; new techniques based on acoustic radiation force. This allowing sonographers to merge real-time ultrasound with year also marked the naming of the UR Hajim School of previously acquired CT, MR, or ultrasound images. Engineering and Applied Sciences. The University of Rochester Medical Center was The RCBU continues to play a prominent role represented by sonographers and physicians in education in clinical and technological advances in the use of nationally and internationally. As faculty for Armed ultrasound for diagnostic imaging and therapy. Nonlinear Forces Institute of Pathology, Washington DC, Dr. imaging techniques, sonoelastography, and ultrasound Rubens continued to teach courses on spleen, testis, contrast agents all have foundations from innovations scrotum, portal Doppler, and testicular Doppler. Drs. within RCBU laboratories. Highlights of the Eighth Bhatt, Dogra, Rubens, Strang, and Voci also participated International Conference on Ultrasonic Measurement as faculty at the Radiological Society of North America and Imaging of Tissue Elasticity are reviewed in this (RSNA), the American Institute of Ultrasound in Medicine report. Collaborative projects between RCBU clinicians, (AIUM), the Society of Gastrointestinal Radiologists engineers, and scientists continue to advance novel (SGR), and the Society of Uroradiology (SUR) Annual diagnostic and therapeutic applications of ultrasound. Meetings. This annual report details research from RCBU Dr. Rubens continued her research with the BME members on many topics in biomedical ultrasound, Department in collaboration with General Electric and including sonoelastography, acoustic radiation force Rensselaer Polytechnical Institute on the NIH funded imaging, ultrasound for tissue engineering, intravascular grant, 3DProstate Cancer Imaging Based on “Crawling ultrasound, ultrasound therapies, acoustic cavitation, and Wave” Excitation, to create and assess a novel 3D bioeffects. The RCBU also provides a rich environment imaging scanner applied to prostate cancer. The for education and training in biomedical ultrasound. This Ultrasound Division is also co-investigator with Duke annual report highlights educational advances, as well University, in assessing DVT in oncology patients. Dr. as special awards and achievements by RCBU members Charles Francis, URMC faculty and Dr. Gary Lyman, and students. We welcome your comments on any of the Duke University, are Principal Investigators on the study. enclosed reports. 4 RCBU FUNDING NEWS Marvin Doyley was Maria Helguera, Diane Dalecki, and Denise Hocking awarded an NIH grant received NIH funding for collaborative investigations titled “IVUS Detection focused on developing novel ultrasound tissue of Rupture Prone characterization and imaging techniques for Plaques.” The project is engineered tissues. This work is part of a larger devoted to developing project funded by the NIH to develop ultrasound- ultrasonic methods to based technologies for the field of tissue engineering. assess the functional Through this new collaborative project, Dr. Helguera and structural properties will spend part of the academic year and summer as a of life-threatening Visiting Scientist in Dr. Dalecki’s laboratory. (See atherosclerotic plaques related story on page 20). and the arterial wall (see Above: Marvin Doyley, PhD related story on page 16). Dr. Doyley also received funding from the HSCCI/ Below: Denise DCFAR for the project “Elastographic Imaging of HIV Hocking, PhD Associated Brain Injury.” Robert Waag was awarded a grant from the NIH for the project titled “Ultrasound Imaging of Breast by use of a Hemispheric Array and Inverse Scattering.” The objective of the project is to form high-resolution Above: Maria Above: Diane speckle-free quantitative ultrasound images Helguera, PhD Dalecki, PhD throughout the volume of the breast in vivo by using a hemispheric transducer array for measurements and inverse scattering for image reconstruction. Amy Lerner, Ben Castañeda, and Scott Seidman Maria Helguera is a co-Principal Investigator on a new received funding from the National Collegiate project supported by the NIH titled “NTHI Immunity Inventors and Innovators Alliance for their project in Young Children.” This project focuses on using titled “UR-PUCP: Collaborations for Healthcare in ultrasound in the detection and characterization of Developing Countries." This funding has established a biofilms (see story on page 21). new joint program between the University of Rochester and Pontificia Universidad Catolica del Peru Sheryl Gracewski received funding for summer that provides opportunities for students to work on research students through the UR Xerox Summer biomedical engineering projects dedicated to Research Program, and through an REU on her NSF enhancing health care in developing countries. (See grant titled “Dynamic Response of Constrained related story on page 21.) Bubbles to Acoustic Excitation.” Carlos Sevilla, a graduate student in the Department Ben Castañeda received support from the Lindbergh of Biomedical Engineering, was awarded a prestigious Foundation for his project “Developing Computerized NIH Ruth L. Kirschstein National Research Service Screening for Early Detection of Tuberculosis in Award Individual Pre-doctoral Fellowship. This three- Peru.” He also received funding for the project “Area year award will provide funding for his thesis research Measurement of Cutaneous Leishmaniasis Wounds,” project titled, “Promoting Chronic Wound Healing from the Dirección Académica de Investigación of the with Ultrasound and Fibronectin.” His thesis research Pontificia Universidad Catolica del Peru. is co-advised by Drs. Denise Hocking and Diane Dalecki. Denise Hocking and Diane Dalecki received funding Maria Helguera received funding from NYSTAR-CEIS from the NIH to support the summer research projects Carestream Health, Inc. for a project titled and career development of undergraduate and high “Development of a Novel 3-D Optical Molecular school students. Research areas for student projects Imaging System Prototype.” Dr. Helguera also focus on effects of ultrasound on cells and protein received funding for a project titled “Registration and conformation, and novel applications of acoustic Normalization of Images” from the Museum of Fine radiation force. Arts, Boston. 7 2009 RESEARCH Research laboratories of RCBU members are advancing the use of ultrasound for diagnosis and treatment. The pages that follow highlight research accomplishments in 2009. Publications and presentations of this year can be found on pages 28–29. Minimization of bias due to high amplitude jitter magnitude. If echoes are fully normalized before reflections in displacement estimation using displacement estimation, the blur is minimized, but partial echo normalization SNR is augmented, resulting in a large increase in the jitter magnitude. Instead, normalization of the echo Manoj Menon, MS and Stephen McAleavey, PhD is weighted, such that larger values of an echo are Pathological conditions and their treatments often reduced more than smaller values. Using this partial result in a change in the mechanical properties of normalization technique, high-amplitude reflections tissue. More recently, investigators have used are locally normalized without critically affecting the elastographic techniques for applications such as the quality of the rest of the signal. It was found that by imaging of blood vessels. When there is significant applying this algorithm, the ability to resolve bright acoustic impedance mismatch between objects of boundaries in displacement images significantly interest, strong reflections can occur at the interface. improved for ultrasonic frequencies greater than Windowed 1D cross-correlations based techniques are 4 MHz, and correlation window lengths greater than commonly employed for displacement estimation. 0.6 mm, with only slight increases in jitter. The displacement estimate within a correlation window is assumed to be approximately the average of the displacements within that window. This In vivo prostate cancer detection using assumption holds true when the speckle is sonoelastography: Preliminary results homogeneous. When there is a local high-amplitude Benjamin Castañeda, PhD, Karin Westesson, signal, it tends to dominate the displacement Liwei An, MS, Shuang Wu, MS, Kenneth Hoyt, estimate, causing a bias towards the displacement that PhD, Jorge Yao, Laurie Baxter, John Strang, MD, corresponds spatially to the high amplitude region of Deborah Rubens, MD, Kevin Parker, PhD the echo. This bias results in a blurring of the displacement image in the vicinity
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