University of Oulu

Paakkari, P., Inkinen, S.I., Honkanen, M.K.M. et al. Quantitative dual contrast photon-counting computed tomography for assessment of articular cartilage health. Sci Rep 11, 5556 (2021).

Quantitative dual contrast photon-counting computed tomography for assessment of articular cartilage health

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Author: Paakkari, Petri1,2; Inkinen, Satu I.3; Honkanen, Miitu K. M.1,4;
Organizations: 1Department of Applied Physics, University of Eastern Finland, 70210, Kuopio, Finland
2Center of Oncology, Kuopio University Hospital, Kuopio, Finland
3Research Unit of Medical Imaging, Physics and Technology, University of Oulu, Oulu, Finland
4Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
5A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
6Medical Research Center, University of Oulu, Oulu, Finland
7Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
8Departments of Biomedical Engineering, Chemistry and Medicine, Boston University, Boston, USA
9School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
10Medical Imaging and Radiation Therapy, Kymenlaakso Central Hospital, Kymenlaakso Social and Health Services, Kotka, Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 2 MB)
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Language: English
Published: Springer Nature, 2021
Publish Date: 2021-05-19


Photon-counting detector computed tomography (PCD-CT) is a modern spectral imaging technique utilizing photon-counting detectors (PCDs). PCDs detect individual photons and classify them into fixed energy bins, thus enabling energy selective imaging, contrary to energy integrating detectors that detects and sums the total energy from all photons during acquisition. The structure and composition of the articular cartilage cannot be detected with native CT imaging but can be assessed using contrast-enhancement. Spectral imaging allows simultaneous decomposition of multiple contrast agents, which can be used to target and highlight discrete cartilage properties. Here we report, for the first time, the use of PCD-CT to quantify a cationic iodinated CA4+ (targeting proteoglycans) and a non-ionic gadolinium-based gadoteridol (reflecting water content) contrast agents inside human osteochondral tissue (n = 53). We performed PCD-CT scanning at diffusion equilibrium and compared the results against reference data of biomechanical and optical density measurements, and Mankin scoring. PCD-CT enables simultaneous quantification of the two contrast agent concentrations inside cartilage and the results correlate with the structural and functional reference parameters. With improved soft tissue contrast and assessment of proteoglycan and water contents, PCD-CT with the dual contrast agent method is of potential use for the detection and monitoring of osteoarthritis.

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Series: Scientific reports
ISSN: 2045-2322
ISSN-E: 2045-2322
ISSN-L: 2045-2322
Volume: 11
Issue: 1
Article number: 5556
DOI: 10.1038/s41598-021-84800-x
Type of Publication: A1 Journal article – refereed
Field of Science: 217 Medical engineering
Funding: This work was supported by Academy of Finland (project number 316899, 316258), Kuopio University Hospital (VTR grant numbers 5041769, 5041778, and 5654199), Business Finland (project number 1392/31/2016), The Finnish Foundation for Technology Promotion (project numbers 6227 and 8193), Päivikki and Sakari Sohlberg Foundation, Instrumentarium Science Foundation, the Vilho, Yrjö and Kalle Väisälä Foundation of the Finnish Academy of Science and Letters, MIRACLE project (grant agreement 780598), and Europe Union’s Horizon 2020 research and innovation program (H2020-ICT-2017-1).
EU Grant Number: (780598) MIRACLE - Mid-infrared arthroscopy innovative imaging system for real-time clinical in depth examination and diagnosis of degenerative joint diseases
Academy of Finland Grant Number: 316899
Detailed Information: 316899 (Academy of Finland Funding decision)
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