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Tuppurainen J, Paakkari P, Jäntti J, Nissinen MT, Fugazzola MC, van Weeren R, Ylisiurua S, Nieminen MT, Kröger H, Snyder BD, Joenathan A, Grinstaff MW, Matikka H, Korhonen RK, Mäkelä JTA. Revealing Detailed Cartilage Function Through Nanoparticle Diffusion Imaging: A Computed Tomography & Finite Element Study. Ann Biomed Eng 2024; 52:2584-2595. [PMID: 39012563 PMCID: PMC11329549 DOI: 10.1007/s10439-024-03552-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 05/23/2024] [Indexed: 07/17/2024]
Abstract
The ability of articular cartilage to withstand significant mechanical stresses during activities, such as walking or running, relies on its distinctive structure. Integrating detailed tissue properties into subject-specific biomechanical models is challenging due to the complexity of analyzing these characteristics. This limitation compromises the accuracy of models in replicating cartilage function and impacts predictive capabilities. To address this, methods revealing cartilage function at the constituent-specific level are essential. In this study, we demonstrated that computational modeling derived individual constituent-specific biomechanical properties could be predicted by a novel nanoparticle contrast-enhanced computer tomography (CECT) method. We imaged articular cartilage samples collected from the equine stifle joint (n = 60) using contrast-enhanced micro-computed tomography (µCECT) to determine contrast agents' intake within the samples, and compared those to cartilage functional properties, derived from a fibril-reinforced poroelastic finite element model. Two distinct imaging techniques were investigated: conventional energy-integrating µCECT employing a cationic tantalum oxide nanoparticle (Ta2O5-cNP) contrast agent and novel photon-counting µCECT utilizing a dual-contrast agent, comprising Ta2O5-cNP and neutral iodixanol. The results demonstrate the capacity to evaluate fibrillar and non-fibrillar functionality of cartilage, along with permeability-affected fluid flow in cartilage. This finding indicates the feasibility of incorporating these specific functional properties into biomechanical computational models, holding potential for personalized approaches to cartilage diagnostics and treatment.
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Affiliation(s)
- Juuso Tuppurainen
- Department of Technical Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland.
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland.
| | - Petri Paakkari
- Department of Technical Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Jiri Jäntti
- Department of Technical Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Mikko T Nissinen
- Department of Technical Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
| | - Maria C Fugazzola
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - René van Weeren
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Sampo Ylisiurua
- Research Unit of Health Sciences and Technology, University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
| | - Miika T Nieminen
- Research Unit of Health Sciences and Technology, University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
| | - Heikki Kröger
- Department of Orthopaedics and Traumatology, Kuopio University Hospital, Kuopio, Finland
- Kuopio Musculoskeletal Research Unit, University of Eastern Finland, Kuopio, Finland
| | - Brian D Snyder
- Department of Orthopedic Surgery, Boston Children's Hospital, Boston, USA
| | - Anisha Joenathan
- Departments of Biomedical Engineering and Chemistry, Boston University, Boston, USA
| | - Mark W Grinstaff
- Departments of Biomedical Engineering and Chemistry, Boston University, Boston, USA
| | - Hanna Matikka
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Rami K Korhonen
- Department of Technical Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
| | - Janne T A Mäkelä
- Department of Technical Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
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2
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B Wrammerfors ET, Törnquist E, Pierantoni M, Sjögren A, Tengattini A, Kaestner A, Zandt RI', Englund M, Isaksson H. Exploratory neutron tomography of articular cartilage. Osteoarthritis Cartilage 2024; 32:702-712. [PMID: 38447631 DOI: 10.1016/j.joca.2024.02.889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 02/28/2024] [Accepted: 02/28/2024] [Indexed: 03/08/2024]
Abstract
OBJECTIVE To investigate the feasibility of using neutron tomography to gain new knowledge of human articular cartilage degeneration in osteoarthritis (OA). Different sample preparation techniques were evaluated to identify maximum intra-tissue contrast. DESIGN Human articular cartilage samples from 14 deceased donors (18-75 years, 9 males, 5 females) and 4 patients undergoing total knee replacement due to known OA (all female, 61-75 years) were prepared using different techniques: control in saline, treated with heavy water saline, fixed and treated in heavy water saline, and fixed and dehydrated with ethanol. Neutron tomographic imaging (isotropic voxel sizes from 7.5 to 13.5 µm) was performed at two large scale facilities. The 3D images were evaluated for gradients in hydrogen attenuation as well as compared to images from absorption X-ray tomography, magnetic resonance imaging, and histology. RESULTS Cartilage was distinguishable from background and other tissues in neutron tomographs. Intra-tissue contrast was highest in heavy water-treated samples, which showed a clear gradient from the cartilage surface to the bone interface. Increased neutron flux or exposure time improved image quality but did not affect the ability to detect gradients. Samples from older donors showed high variation in gradient profile, especially from donors with known OA. CONCLUSIONS Neutron tomography is a viable technique for specialized studies of cartilage, particularly for quantifying properties relating to the hydrogen density of the tissue matrix or water movement in the tissue.
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Affiliation(s)
| | - Elin Törnquist
- Department of Biomedical Engineering, Lund University (LU), Sweden
| | - Maria Pierantoni
- Department of Biomedical Engineering, Lund University (LU), Sweden
| | - Amanda Sjögren
- Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund, LU, Sweden
| | | | - Anders Kaestner
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut (PSI), Switzerland
| | | | - Martin Englund
- Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund, LU, Sweden
| | - Hanna Isaksson
- Department of Biomedical Engineering, Lund University (LU), Sweden
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3
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Orava H, Paakkari P, Jäntti J, Honkanen MKM, Honkanen JTJ, Virén T, Joenathan A, Tanska P, Korhonen RK, Grinstaff MW, Töyräs J, Mäkelä JTA. Triple contrast computed tomography reveals site-specific biomechanical differences in the human knee joint-A proof of concept study. J Orthop Res 2024; 42:415-424. [PMID: 37593815 DOI: 10.1002/jor.25683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/05/2023] [Accepted: 08/14/2023] [Indexed: 08/19/2023]
Abstract
Cartilage and synovial fluid are challenging to observe separately in native computed tomography (CT). We report the use of triple contrast agent (bismuth nanoparticles [BiNPs], CA4+, and gadoteridol) to image and segment cartilage in cadaveric knee joints with a clinical CT scanner. We hypothesize that BiNPs will remain in synovial fluid while the CA4+ and gadoteridol will diffuse into cartilage, allowing (1) segmentation of cartilage, and (2) evaluation of cartilage biomechanical properties based on contrast agent concentrations. To investigate these hypotheses, triple contrast agent was injected into both knee joints of a cadaver (N = 1), imaged with a clinical CT at multiple timepoints during the contrast agent diffusion. Knee joints were extracted, imaged with micro-CT (µCT), and biomechanical properties of the cartilage surface were determined by stress-relaxation mapping. Cartilage was segmented and contrast agent concentrations (CA4+ and gadoteridol) were compared with the biomechanical properties at multiple locations (n = 185). Spearman's correlation between cartilage thickness from clinical CT and reference µCT images verifies successful and reliable segmentation. CA4+ concentration is significantly higher in femoral than in tibial cartilage at 60 min and further timepoints, which corresponds to the higher Young's modulus observed in femoral cartilage. In this pilot study, we show that (1) large BiNPs do not diffuse into cartilage, facilitating straightforward segmentation of human knee joint cartilage in a clinical setting, and (2) CA4+ concentration in cartilage reflects the biomechanical differences between femoral and tibial cartilage. Thus, the triple contrast agent CT shows potential in cartilage morphology and condition estimation in clinical CT.
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Affiliation(s)
- Heta Orava
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Petri Paakkari
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Jiri Jäntti
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Miitu K M Honkanen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | | | - Tuomas Virén
- Center of Oncology, Kuopio University Hospital, Kuopio, Finland
| | - Anisha Joenathan
- Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, Boston, Massachusetts, USA
| | - Petri Tanska
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Rami K Korhonen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Mark W Grinstaff
- Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, Boston, Massachusetts, USA
| | - Juha Töyräs
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Science Service Center, Kuopio University Hospital, Kuopio, Finland
- School of Electrical Engineering and Computer Science, The University of Queensland, Brisbane, Australia
| | - Janne T A Mäkelä
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
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4
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Duvančić T, Škokić S, Erjavec I, Plečko M, Bohaček I, Gajović S, Delimar D. Novel micro-MRI approach for subchondral trabecular bone analysis in patients with hip osteoarthritis is comparable to micro-CT approach. Croat Med J 2022; 63:515-524. [PMID: 36597563 PMCID: PMC9837720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
AIM To test the agreement between a newly developed micro-magnetic resonance imaging (MRI) analysis of the subchondral bone and the micro-computed tomography (CT) approach. METHODS Samples obtained from 10 patients with osteoarthritis undergoing total hip arthroplasty were scanned with a 7.0 T micro-MRI. Proton density-weighted images and proton density-weighted images with fat suppression were obtained. The results were validated with a micro-CT device. Micro-MRI and micro-CT scans of the same sample were aligned, and regions of interest were delineated on equal areas of the sample. Bone volume fraction was calculated by using in-house plugins. The agreement between the methods was tested with Bland-Altman analysis. RESULTS The agreement between the methods was good, with average difference of 2.167%. The differences between the methods were not significant (P=0.272, t test). CONCLUSION The novel micro-MRI approach could be used for subchondral bone analysis. With further optimization for clinical MRI machines, the approach can be also used in the diagnostics of hip osteoarthritis.
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Affiliation(s)
- Tea Duvančić
- University of Zagreb School of Medicine, Zagreb, Croatia
| | - Siniša Škokić
- Laboratory for Regenerative Neuroscience – GlowLab, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Igor Erjavec
- University of Zagreb School of Medicine, Zagreb, Croatia
| | | | - Ivan Bohaček
- Department of Orthopedic Surgery, University of Zagreb School of Medicine, University Hospital Center Zagreb, Zagreb, Croatia
| | - Srećko Gajović
- University of Zagreb School of Medicine, Zagreb, Croatia
| | - Domagoj Delimar
- Department of Orthopedic Surgery, University of Zagreb School of Medicine, University Hospital Center Zagreb, Zagreb, Croatia
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5
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Duvančić T, Škokić S, Erjavec I, Plečko M, Bohaček I, Gajović S, Delimar D. Novel micro-MRI approach for subchondral trabecular bone analysis in patients with hip osteoarthritis is comparable to micro-CT approach. Croat Med J 2022. [PMID: 36597563 PMCID: PMC9837720 DOI: 10.3325/cmj.2022.63.515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
AIM To test the agreement between a newly developed micro-magnetic resonance imaging (MRI) analysis of the subchondral bone and the micro-computed tomography (CT) approach. METHODS Samples obtained from 10 patients with osteoarthritis undergoing total hip arthroplasty were scanned with a 7.0 T micro-MRI. Proton density-weighted images and proton density-weighted images with fat suppression were obtained. The results were validated with a micro-CT device. Micro-MRI and micro-CT scans of the same sample were aligned, and regions of interest were delineated on equal areas of the sample. Bone volume fraction was calculated by using in-house plugins. The agreement between the methods was tested with Bland-Altman analysis. RESULTS The agreement between the methods was good, with average difference of 2.167%. The differences between the methods were not significant (P=0.272, t test). CONCLUSION The novel micro-MRI approach could be used for subchondral bone analysis. With further optimization for clinical MRI machines, the approach can be also used in the diagnostics of hip osteoarthritis.
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Affiliation(s)
- Tea Duvančić
- University of Zagreb School of Medicine, Zagreb, Croatia
| | - Siniša Škokić
- Laboratory for Regenerative Neuroscience – GlowLab, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Igor Erjavec
- University of Zagreb School of Medicine, Zagreb, Croatia
| | | | - Ivan Bohaček
- Department of Orthopedic Surgery, University of Zagreb School of Medicine, University Hospital Center Zagreb, Zagreb, Croatia
| | - Srećko Gajović
- University of Zagreb School of Medicine, Zagreb, Croatia
| | - Domagoj Delimar
- Department of Orthopedic Surgery, University of Zagreb School of Medicine, University Hospital Center Zagreb, Zagreb, Croatia
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6
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A Cationic Contrast Agent in X-ray Imaging of Articular Cartilage: Pre-Clinical Evaluation of Diffusion and Attenuation Properties. Diagnostics (Basel) 2022; 12:diagnostics12092111. [PMID: 36140512 PMCID: PMC9497730 DOI: 10.3390/diagnostics12092111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/24/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
The aim of this study was the preliminary assessment of a new cationic contrast agent, the CA4+, via the analysis of spatial distribution in cartilage of ex vivo bovine samples, at micrometer and millimeter scale. Osteochondral plugs (n = 18) extracted from bovine stifle joints (n = 2) were immersed in CA4+ solution up to 26 h. Planar images were acquired at different time points, using a microCT apparatus. The CA4+ distribution in cartilage and saturation time were evaluated. Tibial plates from bovine stifle joints (n = 3) were imaged with CT, before and after 24 h-CA4+ bath immersion, at different concentrations. Afterward, potential CA4+ washout from cartilage was investigated. From microCT acquisitions, the CA4+ distribution differentiated into three distinct layers inside the cartilage, reflecting the spatial distribution of proteoglycans. After 24 h of diffusion, the iodine concentration reached in cartilage was approximately seven times that of the CA4+ bath. The resulting saturation time was 1.9 ± 0.9 h and 2.6 ± 2.9 h for femoral and tibial samples, respectively. Analysis of clinical CT acquisitions confirmed overall contrast enhancement of cartilage after 24 h immersion, observed for each CA4+ concentration. Distinct contrast enhancement was reached in different cartilage regions, depending on tissue’s local features. Incomplete but remarkable washout of cartilage was observed. CA4+ significantly improved cartilage visualization and its qualitative analysis.
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7
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Hall ME, Wang AS, Gold GE, Levenston ME. Contrast solution properties and scan parameters influence the apparent diffusivity of computed tomography contrast agents in articular cartilage. J R Soc Interface 2022; 19:20220403. [PMID: 35919981 PMCID: PMC9346352 DOI: 10.1098/rsif.2022.0403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/08/2022] [Indexed: 11/12/2022] Open
Abstract
The inability to detect early degenerative changes to the articular cartilage surface that commonly precede bulk osteoarthritic degradation is an obstacle to early disease detection for research or clinical diagnosis. Leveraging a known artefact that blurs tissue boundaries in clinical arthrograms, contrast agent (CA) diffusivity can be derived from computed tomography arthrography (CTa) scans. We combined experimental and computational approaches to study protocol variations that may alter the CTa-derived apparent diffusivity. In experimental studies on bovine cartilage explants, we examined how CA dilution and transport direction (absorption versus desorption) influence the apparent diffusivity of untreated and enzymatically digested cartilage. Using multiphysics simulations, we examined mechanisms underlying experimental observations and the effects of image resolution, scan interval and early scan termination. The apparent diffusivity during absorption decreased with increasing CA concentration by an amount similar to the increase induced by tissue digestion. Models indicated that osmotically-induced fluid efflux strongly contributed to the concentration effect. Simulated changes to spatial resolution, scan spacing and total scan time all influenced the apparent diffusivity, indicating the importance of consistent protocols. With careful control of imaging protocols and interpretations guided by transport models, CTa-derived diffusivity offers promise as a biomarker for early degenerative changes.
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Affiliation(s)
- Mary E. Hall
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
| | - Adam S. Wang
- Department of Radiology, Stanford University, Stanford, CA, USA
- Department of Electrical Engineering, Stanford University, Stanford, CA, USA
| | - Garry E. Gold
- Department of Radiology, Stanford University, Stanford, CA, USA
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Marc E. Levenston
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
- Department of Radiology, Stanford University, Stanford, CA, USA
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8
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Saukko AEA, Nykänen O, Sarin JK, Nissi MJ, Te Moller NCR, Weinans H, Mancini IAD, Visser J, Brommer H, van Weeren PR, Malda J, Grinstaff MW, Töyräs J. Dual-contrast computed tomography enables detection of equine posttraumatic osteoarthritis in vitro. J Orthop Res 2022; 40:703-711. [PMID: 33982283 DOI: 10.1002/jor.25066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 04/26/2021] [Indexed: 02/04/2023]
Abstract
To prevent the progression of posttraumatic osteoarthritis, assessment of cartilage composition is critical for effective treatment planning. Posttraumatic changes include proteoglycan (PG) loss and elevated water content. Quantitative dual-energy computed tomography (QDECT) provides a means to diagnose these changes. Here, we determine the potential of QDECT to evaluate tissue quality surrounding cartilage lesions in an equine model, hypothesizing that QDECT allows detection of posttraumatic degeneration by providing quantitative information on PG and water contents based on the partitions of cationic and nonionic agents in a contrast mixture. Posttraumatic osteoarthritic samples were obtained from a cartilage repair study in which full-thickness chondral defects were created surgically in both stifles of seven Shetland ponies. Control samples were collected from three nonoperated ponies. The experimental (n = 14) and control samples (n = 6) were immersed in the contrast agent mixture and the distributions of the agents were determined at various diffusion time points. As a reference, equilibrium moduli, dynamic moduli, and PG content were measured. Significant differences (p < 0.05) in partitions between the experimental and control samples were demonstrated with cationic contrast agent at 30 min, 60 min, and 20 h, and with non-ionic agent at 60 and 120 min. Significant Spearman's rank correlations were obtained at 20 and 24 h (ρ = 0.482-0.693) between the partition of cationic contrast agent, cartilage biomechanical properties, and PG content. QDECT enables evaluation of posttraumatic changes surrounding a lesion and quantification of PG content, thus advancing the diagnostics of the extent and severity of cartilage injuries.
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Affiliation(s)
- Annina E A Saukko
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Department of Medical Physics, Turku University Hospital, Turku, Finland
| | - Olli Nykänen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Research Unit of Medical Imaging Physics and Technology, University of Oulu, Oulu, Finland
| | - Jaakko K Sarin
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Mikko J Nissi
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Research Unit of Medical Imaging Physics and Technology, University of Oulu, Oulu, Finland
| | - Nikae C R Te Moller
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Harrie Weinans
- Department of Biomechanical Engineering, Delft University of Technology (TU Delft), Delft, The Netherlands.,Department of Orthopedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Irina A D Mancini
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Jetze Visser
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Harold Brommer
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - P Réné van Weeren
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Jos Malda
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Department of Orthopedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Mark W Grinstaff
- Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, Boston, Massachusetts, USA
| | - Juha Töyräs
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland.,School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia.,Science Service Center, Kuopio University Hospital, Kuopio, Finland
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9
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Effarah HH, Reutershan T, Lagzda A, Hwang Y, Hartemann FV, Barty CPJ. Computational method for the optimization of quasimonoenergetic laser Compton x-ray sources for imaging applications. APPLIED OPTICS 2022; 61:C143-C153. [PMID: 35201039 PMCID: PMC10619704 DOI: 10.1364/ao.444307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
The development of compact quasimonoenergetic x-ray radiation sources based on laser Compton scattering (LCS) offers opportunities for novel approaches to medical imaging. However, careful experimental design is required to fully utilize the angle-correlated x-ray spectra produced by LCS sources. Direct simulations of LCS x-ray spectra are computationally expensive and difficult to employ in experimental optimization. In this manuscript, we present a computational method that fully characterizes angle-correlated LCS x-ray spectra at any end point energy within a range defined by three direct simulations. With this approach, subsequent LCS x-ray spectra can be generated with up to 200 times less computational overhead.
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Affiliation(s)
- Haytham H. Effarah
- Department of Physics and Astronomy, University of California – Irvine, Irvine, CA, 92617, USA
- Beckman Laser Institute and Medical Clinic, University of California – Irvine, Irvine, CA 92612, USA
| | - Trevor Reutershan
- Department of Physics and Astronomy, University of California – Irvine, Irvine, CA, 92617, USA
- Beckman Laser Institute and Medical Clinic, University of California – Irvine, Irvine, CA 92612, USA
| | - Agnese Lagzda
- Lumitron Technologies, Inc., 5201 California Ave, Suite 100, Irvine, CA, 92617, USA
| | - Yoonwoo Hwang
- Lumitron Technologies, Inc., 5201 California Ave, Suite 100, Irvine, CA, 92617, USA
| | - Fred V. Hartemann
- Lumitron Technologies, Inc., 5201 California Ave, Suite 100, Irvine, CA, 92617, USA
| | - C. P. J. Barty
- Department of Physics and Astronomy, University of California – Irvine, Irvine, CA, 92617, USA
- Beckman Laser Institute and Medical Clinic, University of California – Irvine, Irvine, CA 92612, USA
- Lumitron Technologies, Inc., 5201 California Ave, Suite 100, Irvine, CA, 92617, USA
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10
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Bhattarai A, Mäkelä JTA, Pouran B, Kröger H, Weinans H, Grinstaff MW, Töyräs J, Turunen MJ. Effects of human articular cartilage constituents on simultaneous diffusion of cationic and nonionic contrast agents. J Orthop Res 2021; 39:771-779. [PMID: 32767676 PMCID: PMC8048551 DOI: 10.1002/jor.24824] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/03/2020] [Accepted: 08/05/2020] [Indexed: 02/04/2023]
Abstract
Contrast-enhanced computed tomography is an emerging diagnostic technique for osteoarthritis. However, the effects of increased water content, as well as decreased collagen and proteoglycan concentrations due to cartilage degeneration, on the diffusion of cationic and nonionic agents, are not fully understood. We hypothesize that for a cationic agent, these variations increase the diffusion rate while decreasing partition, whereas, for a nonionic agent, these changes increase both the rate of diffusion and partition. Thus, we examine the diffusion of cationic and nonionic contrast agents within degraded tissue in time- and depth-dependent manners. Osteochondral plugs (N = 15, d = 8 mm) were extracted from human cadaver knee joints, immersed in a mixture of cationic CA4+ and nonionic gadoteridol contrast agents, and imaged at multiple time-points, using the dual-contrast method. Water content, and collagen and proteoglycan concentrations were determined using lyophilization, infrared spectroscopy, and digital densitometry, respectively. Superficial to mid (0%-60% depth) cartilage CA4+ partitions correlated with water content (R < -0.521, P < .05), whereas in deeper (40%-100%) cartilage, CA4+ correlated only with proteoglycans (R > 0.671, P < .01). Gadoteridol partition correlated inversely with collagen concentration (0%-100%, R < -0.514, P < .05). Cartilage degeneration substantially increased the time for CA4+ compared with healthy tissue (248 ± 171 vs 175 ± 95 minute) to reach the bone-cartilage interface, whereas for gadoteridol the time (111 ± 63 vs 179 ± 163 minute) decreased. The work clarifies the diffusion mechanisms of two different contrast agents and presents depth and time-dependent effects resulting from articular cartilage constituents. The results will inform the development of new contrast agents and optimal timing between agent administration and joint imaging.
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Affiliation(s)
- Abhisek Bhattarai
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- Diagnostic Imaging CenterKuopio University HospitalKuopioFinland
| | | | - Behdad Pouran
- Department of OrthopaedicsUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Heikki Kröger
- Department of Orthopedics, Traumatology and Hand SurgeryKuopio University HospitalKuopioFinland
| | - Harrie Weinans
- Department of OrthopaedicsUniversity Medical Center UtrechtUtrechtThe Netherlands
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime, and Materials EngineeringDelft University of Technology (TU Delft)DelftThe Netherlands
| | - Mark W. Grinstaff
- Departments of Biomedical Engineering, Chemistry, and MedicineBoston UniversityBostonMassachusetts
| | - Juha Töyräs
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- Diagnostic Imaging CenterKuopio University HospitalKuopioFinland
- School of Information Technology and Electrical EngineeringThe University of QueenslandBrisbaneAustralia
| | - Mikael J. Turunen
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- SIB LabsUniversity of Eastern FinlandKuopioFinland
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Quantitative dual contrast photon-counting computed tomography for assessment of articular cartilage health. Sci Rep 2021; 11:5556. [PMID: 33692379 PMCID: PMC7946949 DOI: 10.1038/s41598-021-84800-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 02/09/2021] [Indexed: 01/31/2023] Open
Abstract
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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12
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Berry DB, Englund EK, Chen S, Frank LR, Ward SR. Medical imaging of tissue engineering and regenerative medicine constructs. Biomater Sci 2021; 9:301-314. [PMID: 32776044 PMCID: PMC8262082 DOI: 10.1039/d0bm00705f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advancement of tissue engineering and regenerative medicine (TERM) strategies to replicate tissue structure and function has led to the need for noninvasive assessment of key outcome measures of a construct's state, biocompatibility, and function. Histology based approaches are traditionally used in pre-clinical animal experiments, but are not always feasible or practical if a TERM construct is going to be tested for human use. In order to transition these therapies from benchtop to bedside, rigorously validated imaging techniques must be utilized that are sensitive to key outcome measures that fulfill the FDA standards for TERM construct evaluation. This review discusses key outcome measures for TERM constructs and various clinical- and research-based imaging techniques that can be used to assess them. Potential applications and limitations of these techniques are discussed, as well as resources for the processing, analysis, and interpretation of biomedical images.
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Affiliation(s)
- David B Berry
- Departments of NanoEngineering, University of California, San Diego, USA.
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13
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Bhattarai A, Pouran B, Mäkelä JTA, Shaikh R, Honkanen MKM, Prakash M, Kröger H, Grinstaff MW, Weinans H, Jurvelin JS, Töyräs J. Dual contrast in computed tomography allows earlier characterization of articular cartilage over single contrast. J Orthop Res 2020; 38:2230-2238. [PMID: 32525582 DOI: 10.1002/jor.24774] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 05/14/2020] [Accepted: 05/28/2020] [Indexed: 02/04/2023]
Abstract
Cationic computed tomography contrast agents are more sensitive for detecting cartilage degeneration than anionic or non-ionic agents. However, osteoarthritis-related loss of proteoglycans and increase in water content contrarily affect the diffusion of cationic contrast agents, limiting their sensitivity. The quantitative dual-energy computed tomography technique allows the simultaneous determination of the partitions of iodine-based cationic (CA4+) and gadolinium-based non-ionic (gadoteridol) agents in cartilage at diffusion equilibrium. Normalizing the cationic agent partition at diffusion equilibrium with that of the non-ionic agent improves diagnostic sensitivity. We hypothesize that this sensitivity improvement is also prominent during early diffusion time points and that the technique is applicable during contrast agent diffusion. To investigate the validity of this hypothesis, osteochondral plugs (d = 8 mm, N = 33), extracted from human cadaver (n = 4) knee joints, were immersed in a contrast agent bath (a mixture of CA4+ and gadoteridol) and imaged using the technique at multiple time points until diffusion equilibrium. Biomechanical testing and histological analysis were conducted for reference. Quantitative dual-energy computed tomography technique enabled earlier determination of cartilage proteoglycan content over single contrast. The correlation coefficient between human articular cartilage proteoglycan content and CA4+ partition increased with the contrast agent diffusion time. Gadoteridol normalized CA4+ partition correlated significantly (P < .05) with Mankin score at all time points and with proteoglycan content after 4 hours. The technique is applicable during diffusion, and normalization with gadoteridol partition improves the sensitivity of the CA4+ contrast agent.
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Affiliation(s)
- Abhisek Bhattarai
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Behdad Pouran
- Department of Orthopaedic, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Janne T A Mäkelä
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Rubina Shaikh
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Miitu K M Honkanen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Mithilesh Prakash
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Heikki Kröger
- Department of Orthopedics, Traumatology and Hand Surgery, Kuopio University Hospital, Kuopio, Finland
| | - Mark W Grinstaff
- Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, Boston, Massachusetts
| | - Harrie Weinans
- Department of Orthopaedic, University Medical Center Utrecht, Utrecht, The Netherlands.,Department of Biomechanical Engineering, Faculty of Mechanical, Maritime, and Materials Engineering, Delft University of Technology (TU Delft), Delft, The Netherlands.,Department of Rheumatology, University Medical Center, Utrecht, The Netherlands
| | - Jukka S Jurvelin
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Juha Töyräs
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland.,School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
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14
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Freedman JD, Ellis DJ, Lusic H, Varma GV, Grant AK, Lakin BA, Snyder BD, Grinstaff MW. dGEMRIC and CECT Comparison of Cationic and Anionic Contrast Agents in Cadaveric Human Metacarpal Cartilage. J Orthop Res 2020; 38:719-725. [PMID: 31687789 PMCID: PMC7071952 DOI: 10.1002/jor.24511] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 10/31/2019] [Indexed: 02/04/2023]
Abstract
Magnetic resonance imaging (MRI) and computed tomography (CT) are widely used to image cartilage and their diagnostic capability is enhanced in the presence of contrast agents. The aim of the study is to directly compare the performance between commercial anionic MRI (Gd(DTPA), Gd2-) and CT (Ioxaglate, Iox1-) contrast agents with novel cationic MRI (Gd(DTPA)Lys2 , Gd4+) and CT (CA4+) contrast agents for assessment of cartilage mechanical and biochemical properties using the ex vivo human osteoarthritis metacarpal cartilage model. First, indentation testing was conducted to obtain the compressive modulus of the human fifth metacarpals. The samples were then immersed in the anionic and cationic contrast agents prior to delayed gadolinium-enhanced MRI of cartilage and CT scanning, respectively. The cartilage glycosaminoglycan (GAG) content and distribution were determined using the 1,9-dimethylmethylene blue assay and Safranin-O histology. Cationic agents significantly accumulate in cartilage compared with anionic agents. Significant positive correlations (p < 0.05) exist between imaging results of cationic agents and GAG content (Gd4+: R2 = 0.43; CA4+: R2 = 0.67) and indentation equilibrium modulus (Gd4+: R2 = 0.48; CA4+: R2 = 0.77). Significant negative correlations are observed between anionic MRI relaxation times, but not contrast-enhanced computed tomography attenuation and cartilage GAG content (Gd2-: R2 = 0.56, p < 0.05; Iox1-: R2 = 0.31, p > 0.05) and indentation equilibrium modulus (Gd2-: R2 = 0.38, p < 0.05; Iox1-: R2 = 0.17, p > 0.05). MRI or CT with cationic contrast agents provides greater sensitivity than their anionic analogs at assessing the biochemical and biomechanical properties of ex vivo human metacarpal cartilage. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:719-725, 2020.
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Affiliation(s)
- Jonathan D. Freedman
- Department of Pharmacology, Boston University, Boston, MA
- Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Daniel J. Ellis
- Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Hrvoje Lusic
- Department of Chemistry, Boston University, Boston, MA
| | - Gopal V. Varma
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Aaron K. Grant
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Benjamin A. Lakin
- Department of Biomedical Engineering, Boston University, Boston, MA
- Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Brian D. Snyder
- Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Orthopaedic Surgery, Boston Children’s Hospital, Boston, MA
| | - Mark W. Grinstaff
- Department of Pharmacology, Boston University, Boston, MA
- Department of Chemistry, Boston University, Boston, MA
- Department of Biomedical Engineering, Boston University, Boston, MA
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15
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Honkanen MKM, Saukko AEA, Turunen MJ, Shaikh R, Prakash M, Lovric G, Joukainen A, Kröger H, Grinstaff MW, Töyräs J. Synchrotron MicroCT Reveals the Potential of the Dual Contrast Technique for Quantitative Assessment of Human Articular Cartilage Composition. J Orthop Res 2020; 38:563-573. [PMID: 31535728 PMCID: PMC7065106 DOI: 10.1002/jor.24479] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 09/13/2019] [Indexed: 02/04/2023]
Abstract
Dual contrast micro computed tomography (CT) shows potential for detecting articular cartilage degeneration. However, the performance of conventional CT systems is limited by beam hardening, low image resolution (full-body CT), and long acquisition times (conventional microCT). Therefore, to reveal the full potential of the dual contrast technique for imaging cartilage composition we employ the technique using synchrotron microCT. We hypothesize that the above-mentioned limitations are overcome with synchrotron microCT utilizing monochromatic X-ray beam and fast image acquisition. Human osteochondral samples (n = 41, four cadavers) were immersed in a contrast agent solution containing two agents (cationic CA4+ and non-ionic gadoteridol) and imaged with synchrotron microCT at an early diffusion time point (2 h) and at diffusion equilibrium (72 h) using two monochromatic X-ray energies (32 and 34 keV). The dual contrast technique enabled simultaneous determination of CA4+ (i.e., proteoglycan content) and gadoteridol (i.e., water content) partitions within cartilage. Cartilage proteoglycan content and biomechanical properties correlated significantly (0.327 < r < 0.736, p < 0.05) with CA4+ partition in superficial and middle zones at both diffusion time points. Normalization of the CA4+ partition with gadoteridol partition within the cartilage significantly (p < 0.05) improved the detection sensitivity for human osteoarthritic cartilage proteoglycan content, biomechanical properties, and overall condition (Mankin, Osteoarthritis Research Society International, and International Cartilage Repair Society grading systems). The dual energy technique combined with the dual contrast agent enables assessment of human articular cartilage proteoglycan content and biomechanical properties based on CA4+ partition determined using synchrotron microCT. Additionally, the dual contrast technique is not limited by the beam hardening artifact of conventional CT systems. © 2019 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 38:563-573, 2020.
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Affiliation(s)
- Miitu K. M. Honkanen
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- Diagnostic Imaging CenterKuopio University HospitalKuopioFinland
| | - Annina E. A. Saukko
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- Department of Medical PhysicsTurku University HospitalTurkuFinland
| | - Mikael J. Turunen
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- SIB LabsUniversity of Eastern FinlandKuopioFinland
| | - Rubina Shaikh
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
| | - Mithilesh Prakash
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- Diagnostic Imaging CenterKuopio University HospitalKuopioFinland
- A.I. Virtanen Institute for Molecular SciencesUniversity of Eastern FinlandKuopioFinland
| | - Goran Lovric
- Centre d'lmagerie BioMédicaleÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland
- Swiss Light SourcePaul Scherrer InstituteVilligenSwitzerland
| | - Antti Joukainen
- Department of Orthopedics, Traumatology and Hand SurgeryKuopio University HospitalKuopioFinland
| | - Heikki Kröger
- Department of Orthopedics, Traumatology and Hand SurgeryKuopio University HospitalKuopioFinland
| | - Mark W. Grinstaff
- Departments of Biomedical Engineering, Chemistry, and MedicineBoston UniversityBostonMassachusetts
| | - Juha Töyräs
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
- Diagnostic Imaging CenterKuopio University HospitalKuopioFinland
- School of Information Technology and Electrical EngineeringThe University of QueenslandBrisbaneQueenslandAustralia
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16
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Triple Contrast CT Method Enables Simultaneous Evaluation of Articular Cartilage Composition and Segmentation. Ann Biomed Eng 2019; 48:556-567. [PMID: 31576504 PMCID: PMC6949199 DOI: 10.1007/s10439-019-02362-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 09/11/2019] [Indexed: 12/16/2022]
Abstract
Early degenerative changes of articular cartilage are detected using contrast-enhanced computed tomography (CT) with a cationic contrast agent (CA). However, cationic CA diffusion into degenerated cartilage decreases with proteoglycan depletion and increases with elevated water content, thus hampering tissue evaluation at early diffusion time points. Furthermore, the contrast at synovial fluid-cartilage interface diminishes as a function of diffusion time hindering accurate cartilage segmentation. For the first time, we employ quantitative dual-energy CT (QDECT) imaging utilizing a mixture of three CAs (cationic CA4+ and non-ionic gadoteridol which are sensitive to proteoglycan and water contents, respectively, and bismuth nanoparticles which highlight the cartilage surface) to simultaneously segment the articulating surfaces and determine of the cartilage condition. Intact healthy, proteoglycan-depleted, and mechanically injured bovine cartilage samples (n = 27) were halved and imaged with synchrotron microCT 2-h post immersion in triple CA or in dual CA (CA4+ and gadoteridol). CA4+ and gadoteridol partitions were determined using QDECT, and pairwise evaluation of these partitions was conducted for samples immersed in dual and triple CAs. In conclusion, the triple CA method is sensitive to proteoglycan depletion while maintaining sufficient contrast at the articular surface to enable detection of cartilage lesions caused by mechanical impact.
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