title: Intravascular photoacoustic imaging at 35 and 80 MHz.
abstract: The catheter-based intravascular photoacoustic (IVPA) imaging for diagnosing atherosclerosis, which can provide optical absorption contrast of the arterial wall besides acoustic scattering contrast from the conventional intravascular ultrasound (IVUS) imaging, has been intensively researched recently. The resolution of IVPA is determined by the frequency bandwidth of an ultrasonic transducer. Higher resolution can be achieved by increasing the transducer's working frequency and bandwidth. We introduce IVPA imaging at 35 and 80 MHz by using newly designed integrated IVUS/IVPA probes. This is the first time IVPA has been achieved as high as 80 MHz. Six-micrometer tungsten wires were imaged to evaluate the probes' spatial resolutions and beam patterns. Healthy rabbit aorta was imaged in vitro. Imaging results show that IVPA has superior contrast over IVUS in identifying the arterial wall, and IVPA at 80 MHz demonstrates extraordinary resolution (35 μm) compared to 35 MHz.
authors.affiliation: NIH Ultrasonic Transducer Resource Center, Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.forename: Qifa
authors.initials: Q
authors.lastname: Zhou
authors.forename: K Kirk
authors.initials: KK
authors.lastname: Shung
authors.forename: Zhongping
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000818:Animals; D001011:Aorta / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D003952:Diagnostic Imaging / Q000295:instrumentation* / Q000379:methods*; D057510:Endovascular Procedures / Q000295:instrumentation* / Q000379:methods*; D019047:Phantoms, Imaging; D061088:Photoacoustic Techniques / Q000295:instrumentation* / Q000379:methods*; D011817:Rabbits; D014414:Tungsten / Q000737:chemistry; D018084:Ultrasonography, Interventional / Q000295:instrumentation / Q000379:methods
chemical_list: D014414:Tungsten