title: Fast optical-resolution photoacoustic microscopy using a 2-axis water-proofing MEMS scanner.
abstract: Optical-resolution photoacoustic microscopy (OR-PAM) is a novel label-free microscopic imaging tool to provide in vivo optical absorbing contrasts. Specially, it is crucial to equip a real-time imaging capability without sacrificing high signal-to-noise ratios (SNRs) for identifying and tracking specific diseases in OR-PAM. Herein we demonstrate a 2-axis water-proofing MEMS scanner made of flexible PDMS. This flexible scanner results in a wide scanning range (9 × 4 mm(2) in a transverse plane) and a fast imaging speed (5 B-scan images per second). Further, the MEMS scanner is fabricated in a compact footprint with a size of 15 × 15 × 15 mm(3). More importantly, the scanning ability in water makes the MEMS scanner possible to confocally and simultaneously reflect both ultrasound and laser, and consequently we can maintain high SNRs. The lateral and axial resolutions of the OR-PAM system are 3.6 and 27.7 μm, respectively. We have successfully monitored the flow of carbon particles in vitro with a volumetric display frame rate of 0.14 Hz. Finally, we have successfully obtained in vivo PA images of microvasculatures in a mouse ear. It is expected that our compact and fast OR-PAM system can be significantly useful in both preclinical and clinical applications.
authors.affiliation: Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea.
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea.
authors.forename: Changho
authors.initials: C
authors.lastname: Lee
authors.affiliation: School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea.
authors.forename: Kyungjin
authors.initials: K
authors.lastname: Park
authors.affiliation: 1] Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea [2] School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea.
authors.forename: Geunbae
authors.initials: G
authors.lastname: Lim
authors.affiliation: 1] Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea [2] Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea [3] School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Republic of Korea.
authors.forename: Chulhong
authors.initials: C
authors.lastname: Kim
mesh_terms: D000818:Animals; D002196:Capillaries / Q000502:physiology; D004423:Ear / Q000098:blood supply; D051379:Mice; D008833:Microcirculation / Q000502:physiology*; D008853:Microscopy / Q000295:instrumentation* / Q000379:methods*; D061088:Photoacoustic Techniques / Q000295:instrumentation* / Q000379:methods*