title: Quantified coronary frequency domain optical coherence tomography signal analysis for the evaluation of erythrocyte-rich thrombus: ex-vivo validation study.
abstract: Previous study has demonstrated that erythrocyte-rich thrombi contain more inflammatory cells and reflect high thrombus burden, leading to impaired myocardial reperfusion in myocardial infarction. The aim of this study is to investigate the utility of quantified frequency domain optical coherence tomography (FD-OCT) signal analysis in evaluating the erythrocyte-rich thrombus with ex-vivo materials. We evaluated 54 specimens of coronary artery thrombus obtained by thrombectomy catheter from 8 patients who underwent primary percutaneous coronary intervention. The thrombi were immersed in saline immediately after thrombectomy and FD-OCT image acquisition was performed ex-vivo. Quantitative analysis for all contiguous frames was performed by the dedicated automated software (OCT system software, Light Lab Inc.). For the maximum thrombus area, mean signal intensity (MSI) and normalized standard deviation of signal (NSD) was evaluated. All thrombi were stained using double staining of phosphotungstic acid-hematoxylin and eosin to enable automatic extraction of erythrocyte from fibrin. Computer-assisted analysis was performed using dedicated image processing software (WinROOF, Mitani Corp., Tokyo, Japan) for color identification of the erythrocyte area. Erythrocyte-rich thrombus, defined as % erythrocyte [(erythrocyte area/total thrombus area) × 100] ≥ 10%, showed significantly lower MSI [4.39 ± 0.24 vs. 4.74 ± 0.35, p = 0.002] than that of <10%. The cut-off point for prediction of erythrocyte-rich thrombus was defined as MSI ≤ 4.56, sensitivity: 87.5%, specificity: 82.9%, area under the curve: 0.836, respectively). The present ex-vivo study suggested the utility of quantified FD-OCT signal analysis on the detection of erythrocyte-rich thrombus.
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1 Kaga Itabashi-ku, Tokyo, 173-8605, Japan. yswan500814@gmail.com.
authors.forename: Yoshitaka
authors.identifier: http://orcid.org/0000-0002-8879-4831
authors.initials: Y
authors.lastname: Shiratori
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1 Kaga Itabashi-ku, Tokyo, 173-8605, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Suzuki
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Fukusato
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, 2-11-1 Kaga Itabashi-ku, Tokyo, 173-8605, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kozuma
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D001706:Biopsy; D003324:Coronary Artery Disease / Q000097:blood / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D003328:Coronary Thrombosis / Q000097:blood / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D004912:Erythrocytes / Q000473:pathology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012984:Software; D017131:Thrombectomy; D041623:Tomography, Optical Coherence
keywords: Myocardial infarction; Optical coherence tomography; Pathology; Thrombus