title: Real-Time Observation of Thrombus Growth Process in an Impeller of a Hydrodynamically Levitated Centrifugal Blood Pump by Near-Infrared Hyperspectral Imaging.
abstract: Understanding the thrombus formation in cardiovascular devices such as rotary blood pumps is the most important issue in developing more hemocompatible devices. The objective of this study was to develop a hyperspectral imaging (HSI) method to visualize the thrombus growth process within a rotary blood pump and investigate the optical properties of the thrombus. An in vitro thrombogenic test was conducted using fresh porcine blood and a specially designed hydrodynamically levitated centrifugal blood pump with a transparent bottom. The pump rotating at 3000 rpm circulated the blood at 1.0 L/min. The bottom surface of the pump was illuminated with white light pulsed at the same frequency as the pump rotation, and the backward-scattered light was imaged using the HSI system. Using stroboscopic HSI and an image construction algorithm, dynamic spectral imaging at wavelengths ranging from 608 to 752 nm within the rotating pump was achieved. After completing the experiment, we collected the red thrombus formed in the pump impeller and quantified the thrombus hemoglobin concentration (Hbthrombus ). The spectrum changed around the center of the impeller, and the area of change expanded toward the impeller flow path. The shape corresponded approximately to the shape of the thrombus. The spectrum change indicated that the light scattering derived from red blood cells decreased. The Hbthrombus was 4.7 ± 1.3 g/dL versus a total hemoglobin of 13 ± 0.87 g/dL. The study revealed that Hbthrombus was reduced by the surrounding blood flow.
authors.affiliation: Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Sakota
authors.affiliation: Graduate School of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Murashige
authors.affiliation: Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Kosaka
authors.affiliation: Department of Cardiovascular Surgery, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan.
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nishida
authors.affiliation: Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Maruyama
mesh_terms: D000465:Algorithms; D000818:Animals; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006439:Hemodynamics; D057446:Hydrodynamics; D007091:Image Processing, Computer-Assisted; D011474:Prosthesis Design; D019265:Spectroscopy, Near-Infrared; D049489:Stroboscopy; D013552:Swine; D013927:Thrombosis / Q000097:blood / Q000209:etiology*; D013997:Time Factors
keywords: Hemocompatibility; Hyperspectral imaging; Near-infrared light; Rotary blood pump; Thrombus