title: A sensitive ultrasonic imaging method for targeted contrast microbubble detection.
abstract: We have recently developed a targeted imaging technique for selective and sensitive ultrasound molecular imaging by taking advantage of wideband transient high frequency acoustic emission from ultrasound contrast agents. The imaging modality makes use of a novel multi-frequency co-linear array (two outer 1.4 MHz and one center 5.3 MHz arrays) transducer integrated with the Siemens AntaresSystem. The imaging sequence includes a B-mode imaging pulse sequence in which a short pulse is transmitted with the outer low frequency arrays and received with the inner high frequency array (TLRH: transmit at low frequency and receive at high frequency), followed by a long radiation force pulse to induce immediate bubble adhesion using the center array, and a second B-mode imaging pulse sequence. The RF data obtained from the second B-mode pulse sequence are averaged and then subtracted from the first B-mode sequence. The imaging technique was tested in a targeted imaging phantom, where lipid-shelled biotin microbubbles flow within an avidin coated-cellulose. Results showed that tissue signals were suppressed up to 33 dB and a targeted bubble contrast-to-free bubble signal ratio of up to 23 dB was obtained from the composite sequence imaging.
authors.affiliation: Department of Biomedical Engineering, University of California at Davis, CA 95616, USA. hr.zheng@siat.ac.cn
authors.forename: Hairong
authors.initials: H
authors.lastname: Zheng
authors.forename: Dustin E
authors.initials: DE
authors.lastname: Kruse
authors.forename: Douglas N
authors.initials: DN
authors.lastname: Stephens
authors.forename: Katherine W
authors.initials: KW
authors.lastname: Ferrara
authors.forename: Patrick
authors.initials: P
authors.lastname: Sutcliffe
authors.forename: Edward
authors.initials: E
authors.lastname: Gardner
mesh_terms: D000465:Algorithms; D003287:Contrast Media / Q000032:analysis* / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D045423:Microbubbles; D015336:Molecular Probe Techniques; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*
chemical_list: D003287:Contrast Media