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Park G, Woo S, Kim K, Kim J, Hwang J, Kim SK, Lee H, Lee S, Kwon B, Kim S, Rhee H, Kim W. Noninvasive and Continuous Monitoring of the Core Body Temperature through the Quantitative Measurement of Blood Perfusion Rate. ACS Sens 2023; 8:2975-2985. [PMID: 37432871 DOI: 10.1021/acssensors.3c00273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2023]
Abstract
Core body temperature (CBT) is one of the four vital signs that must be monitored continuously. The continuous recording of CBT is possible through invasive methods by inserting a temperature probe into specific body sites. We report a novel method to monitor CBT through the quantitative measurement of skin blood perfusion rate (ωb,skin). By monitoring the skin temperature, heat flux, and ωb,skin, the arterial blood temperature, equivalent to CBT, can be extracted. ωb,skin is quantitatively evaluated thermally via sinusoidal heating with regulated thermal penetration depth so that the blood perfusion rate is acquired only in the skin. Its quantification is significant because it indicates various physiological events including hyper- or hypothermia, tissue death, and delineation of tumors. A subject showed promising results with steady values of ωb,skin and CBT of 5.2 ± 1.05 × 10-4 s-1 and 36.51 ± 0.23 °C, respectively. For periods where the subject's actual CBT (axillary temperature) did not fall within the estimated range, the average deviation from the actual CBT was only 0.07 °C. This study aims to develop a competent methodology capable of continuously monitoring the CBT and blood perfusion rate at a distant location from the core body region for the diagnosis of a patient's health condition with wearable devices.
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Affiliation(s)
- Gimin Park
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Seungjai Woo
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Kyomin Kim
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Jiyong Kim
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Junphil Hwang
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Sang Kyu Kim
- Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon 16678, Republic of Korea
| | - Hotaik Lee
- Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon 16678, Republic of Korea
| | - Soyoung Lee
- Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon 16678, Republic of Korea
| | - Boksoon Kwon
- Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon 16678, Republic of Korea
| | - Sungho Kim
- Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon 16678, Republic of Korea
| | - Hongsoon Rhee
- Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon 16678, Republic of Korea
| | - Woochul Kim
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
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Bone marrow MR perfusion imaging and potential for tumor evaluation. Skeletal Radiol 2023; 52:477-491. [PMID: 36271181 DOI: 10.1007/s00256-022-04202-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 09/19/2022] [Accepted: 10/04/2022] [Indexed: 02/02/2023]
Abstract
The physiology of bone perfusion is reviewed outlining how it can be measured with dynamic contrast-enhanced MRI as well as intravoxel incoherent imaging. Evaluation of bone perfusion provides a potential means of assessing tumor activity and treatment response beyond that possible with standard MR imaging.
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3
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Prediction Criteria for the Formation of Refracture after Union of a Long Bone Fracture on the Basis of Hemodynamic Changes in the Tissues of the Area of Damage. Bull Exp Biol Med 2022; 174:95-98. [PMID: 36437336 DOI: 10.1007/s10517-022-05655-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Indexed: 11/29/2022]
Abstract
We studied hemodynamic changes in the area of leg bone fracture and determined the prognostic criteria for refracture formation after achieved union. In Wistar rats (n=18), shin bone fracture with external fixation of the fragments was modeled. The union was formed 35 days after osteosynthesis, the device was removed at this term. In 5 cases, a refracture was formed after the termination of fixation. Hemodynamics and local temperature in the tissues in the area of injury were recorded before the start of the experiment and on days 21 and 35 of fixation. In rats with refracture after union, the blood circulation in the area of damage was characterized by a pronounced hypertonicity of the arteries of both large and small diameters, obstruction of venous outflow, and local hyperthermia. This hemodynamics in tissues in the area of damage can serve as an informative criterion for predicting the course of reparative osteogenesis.
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Osteonecrosis of the Femoral Head. J Am Acad Orthop Surg Glob Res Rev 2022; 6:01979360-202205000-00002. [PMID: 35511598 PMCID: PMC9076447 DOI: 10.5435/jaaosglobal-d-21-00176] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 01/23/2022] [Indexed: 11/18/2022]
Abstract
Osteonecrosis of the femoral head is a progressive and debilitating condition with a wide variety of etiologies including trauma, steroid use, and alcohol intake. Diagnosis and staging are based on imaging including MRI at any stage and plain radiography in more advanced lesions. The only definitive treatment is total hip arthroplasty, although numerous treatments including disphosphonates and core decompression are used to delay the progression. Lack of satisfactory conservative measures suggests the need for additional research of osteonecrosis including large patient registries to further understand this condition.
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Schär MO, Ma R, Demange M, Morgan M, Chen T, Ballon DJ, Dyke JP, Deng XH, Rodeo SA. Use of small animal PET-CT imaging for in vivo assessment of tendon-to-bone healing: A pilot study. J Orthop Surg (Hong Kong) 2022; 30:23094990221076654. [PMID: 35245156 DOI: 10.1177/23094990221076654] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The availability of non-invasive means to evaluate and monitor tendon-bone healing processes in-vivo is limited. Micro Positron-Emission-Tomography (µPET) using 18F-Fluoride is a minimally invasive imaging modality, with which osteoblast activity and bone turnover can be assessed. The aim of this study was to investigate the use of serial in-vivo µPET/CT scans to evaluate bone turnover along the graft-tunnel interface in a rat ACL (anterior cruciate ligament) reconstruction model. METHODS Unilateral autograft ACL reconstruction was performed in six rats. µPET/CT-scans using 18F-Fluoride were performed 7, 14, 21, and 28 days postoperatively. Standard uptake values (SUV) were calculated for three tunnel regions (intraarticular aperture (IAA), mid-tunnel, and extraarticular aperture (EAA)) of the proximal tibia. Animals were sacrificed at 28 days and evaluated with µCT and histological analysis. RESULTS SUVs in both bone tunnels showed an increased 18F-Fluoride uptake at 7 days when compared to 14, 21, and 28 days. SUVs showed a gradient on the tibial side, with most bone turnover in the IAA and least in the EAA. At 7, 14, 21, and 28 days, there were significantly higher SUV values in the IAA compared to the EAA (p = .01, < .01, < .01, < .01). SUVs positively correlated with new bone volumetric density obtained with μCT (r = 0.449, p = .013). Volumetric density of newly formed bone detected on μCT correlated with osteoblast numbers observed along the tunnels in histological sections (r = 0.452, p < .016). CONCLUSIONS Serial in-vivo µPET/CT-scanning has the potential to provide insight into bone turnover and therefore osteoblastic activity during the healing process. As a result, it allows us to directly measure the effect of interventional strategies in tendon-bone healing.
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Affiliation(s)
- Michael O Schär
- 573315The Hospital for Special Surgery, New York, NY, USA.,Department of Orthopaedic Surgery and Traumatology, 27252Inselspital, University of Bern, Bern, Switzerland
| | - Richard Ma
- Missouri Orthopaedic Institute, 12271University of Missouri Health Care, Columbia, MO, USA.,Thompson Laboratory for Regenerative Orthopaedics, 12271University of Missouri, Columbia, MO, USA
| | - Marco Demange
- Department of Orthopedic Surgery and Traumatology, 37884University of São Paulo, São Paulo, Brasil
| | - Matthew Morgan
- Veterinary Emergency and Referral Group (VERG), Brooklyn, NY, USA
| | - Tina Chen
- Missouri Orthopaedic Institute, 12271University of Missouri Health Care, Columbia, MO, USA.,Thompson Laboratory for Regenerative Orthopaedics, 12271University of Missouri, Columbia, MO, USA
| | - Douglas J Ballon
- Weill Cornell Medicine, 552254Citigroup Biomedical Imaging Center, New York, NY, USA
| | - Jonathan P Dyke
- Weill Cornell Medicine, 552254Citigroup Biomedical Imaging Center, New York, NY, USA
| | - Xiang-Hua Deng
- 573315The Hospital for Special Surgery, New York, NY, USA
| | - Scott A Rodeo
- 573315The Hospital for Special Surgery, New York, NY, USA
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Salles S, Shepherd J, Vos HJ, Renaud G. Revealing Intraosseous Blood Flow in the Human Tibia With Ultrasound. JBMR Plus 2021; 5:e10543. [PMID: 34761147 PMCID: PMC8567494 DOI: 10.1002/jbm4.10543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 08/23/2021] [Indexed: 11/18/2022] Open
Abstract
Intraosseous blood circulation is thought to have a critical role in bone growth and remodeling, fracture healing, and bone disorders. However, it is rarely considered in clinical practice because of the absence of a suitable noninvasive in vivo measurement technique. In this work, we assessed blood perfusion in tibial cortical bone simultaneously with blood flow in the superficial femoral artery with ultrasound imaging in five healthy volunteers. After suppression of stationary signal with singular‐value‐decomposition, pulsatile blood flow in cortical bone tissue is revealed, following the heart rate measured in the femoral artery. Using a method combining transverse oscillations and phase‐based motion estimation, 2D vector flow was obtained in the cortex of the tibia. After spatial averaging over the cortex, the peak blood velocity along the long axis of the tibia was measured at four times larger than the peak blood velocity across the bone cortex. This suggests that blood flow in central (Haversian) canals is larger than in perforating (Volkmann's) canals, as expected from the intracortical vascular organization in humans. The peak blood velocity indicates a flow from the endosteum to the periosteum and from the heart to the foot for all subjects. Because aging and the development of bone disorders are thought to modify the direction and velocity of intracortical blood flow, their quantification is crucial. This work reports for the first time an in vivo quantification of the direction and velocity of blood flow in human cortical bone. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Sébastien Salles
- Laboratoire d'Imagerie Biomédicale Sorbonne Université, Centre National de la Recherche Scientifique (CNRS) Unités Mixtes de Recherche (UMR) 7371, Institut National de la Santé et de la Recherche Médicale (INSERM) UMR S 1146 Paris France
| | - Jami Shepherd
- Laboratoire d'Imagerie Biomédicale Sorbonne Université, Centre National de la Recherche Scientifique (CNRS) Unités Mixtes de Recherche (UMR) 7371, Institut National de la Santé et de la Recherche Médicale (INSERM) UMR S 1146 Paris France.,Dodd-Walls Centre for Photonic and Quantum Technologies, Department of Physics University of Auckland Auckland New Zealand
| | - Hendrik J Vos
- Department of Cardiology Erasmus MC University Medical Center Rotterdam The Netherlands
| | - Guillaume Renaud
- Laboratoire d'Imagerie Biomédicale Sorbonne Université, Centre National de la Recherche Scientifique (CNRS) Unités Mixtes de Recherche (UMR) 7371, Institut National de la Santé et de la Recherche Médicale (INSERM) UMR S 1146 Paris France.,Department of Imaging Physics Delft University of Technology Delft The Netherlands
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7
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Schulze S, Rothe R, Neuber C, Hauser S, Ullrich M, Pietzsch J, Rammelt S. Men who stare at bone: multimodal monitoring of bone healing. Biol Chem 2021; 402:1397-1413. [PMID: 34313084 DOI: 10.1515/hsz-2021-0170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 07/12/2021] [Indexed: 12/19/2022]
Abstract
Knowledge of the physiological and pathological processes, taking place in bone during fracture healing or defect regeneration, is essential in order to develop strategies to enhance bone healing under normal and critical conditions. Preclinical testing allows a wide range of imaging modalities that may be applied both simultaneously and longitudinally, which will in turn lower the number of animals needed to allow a comprehensive assessment of the healing process. This work provides an up-to-date review on morphological, functional, optical, biochemical, and biophysical imaging techniques including their advantages, disadvantages and potential for combining them in a multimodal and multiscale manner. The focus lies on preclinical testing of biomaterials modified with artificial extracellular matrices in various animal models to enhance bone remodeling and regeneration.
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Affiliation(s)
- Sabine Schulze
- University Center of Orthopaedics, Trauma and Plastic Surgery (OUPC), University Hospital Carl Gustav Carus, D-01307Dresden, Germany.,Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus and Faculty of Medicine, Technische Universität Dresden, D-01307Dresden, Germany
| | - Rebecca Rothe
- Department of Radiopharmaceutical and Chemical Biology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, D-01062Dresden, Germany
| | - Christin Neuber
- Department of Radiopharmaceutical and Chemical Biology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328Dresden, Germany
| | - Sandra Hauser
- Department of Radiopharmaceutical and Chemical Biology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328Dresden, Germany
| | - Martin Ullrich
- Department of Radiopharmaceutical and Chemical Biology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328Dresden, Germany
| | - Jens Pietzsch
- Department of Radiopharmaceutical and Chemical Biology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, D-01062Dresden, Germany
| | - Stefan Rammelt
- University Center of Orthopaedics, Trauma and Plastic Surgery (OUPC), University Hospital Carl Gustav Carus, D-01307Dresden, Germany.,Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus and Faculty of Medicine, Technische Universität Dresden, D-01307Dresden, Germany.,Center for Regenerative Therapies Dresden (CRTD), D-01307Dresden, Germany
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8
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Lu J, Guan H, Wu D, Hu Z, Zhang H, Jiang H, Yu J, Zeng K, Li H, Zhang H, Pan C, Cai D, Yu X. Pseudolaric acid B ameliorates synovial inflammation and vessel formation by stabilizing PPARγ to inhibit NF-κB signalling pathway. J Cell Mol Med 2021; 25:6664-6678. [PMID: 34117708 PMCID: PMC8278075 DOI: 10.1111/jcmm.16670] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/10/2021] [Accepted: 05/08/2021] [Indexed: 12/16/2022] Open
Abstract
Synovial macrophage polarization and inflammation are essential for osteoarthritis (OA) development, yet the molecular mechanisms and regulation responsible for the pathogenesis are still poorly understood. Here, we report that pseudolaric acid B (PAB) attenuated articular cartilage degeneration and synovitis during OA. PAB, a diterpene acid, specifically inhibited NF-κB signalling and reduced the production of pro-inflammatory cytokines, which further decreased M1 polarization and vessel formation. We further provide in vivo and in vitro evidences that PAB suppressed NF-κB signalling by stabilizing PPARγ. Using PPARγ antagonist could abolish anti-inflammatory effect of PAB and rescue the activation of NF-κB signalling during OA. Our findings identify a previously unrecognized role of PAB in the regulation of OA and provide mechanisms by which PAB regulates NF-κB signalling through PPARγ, which further suggest targeting synovial inflammation or inhibiting vessel formation at early stage could be an effective preventive strategy for OA.
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Affiliation(s)
- Jiansen Lu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China.,Department of Orthopedics, Orthopedic Hospital of Guangdong Province, Academy of Orthopedics·Guangdong Province, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.,Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University Guangdong Province, Guangzhou, China
| | - Hong Guan
- Department of Orthopedics, Orthopedic Hospital of Guangdong Province, Academy of Orthopedics·Guangdong Province, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.,The Third School of Clinical Medicine, Southern Medical University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Guangzhou, China.,Department of Joint Surgery, Center for Orthopaedic Surgery, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Dan Wu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Zhiqiang Hu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Hongbo Zhang
- Department of Orthopedics, Orthopedic Hospital of Guangdong Province, Academy of Orthopedics·Guangdong Province, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.,The Third School of Clinical Medicine, Southern Medical University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Guangzhou, China.,Department of Joint Surgery, Center for Orthopaedic Surgery, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Huaji Jiang
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Jingyao Yu
- School of Basic Medical Sciences, Gannan Medical University, Ganzhou, China
| | - Ke Zeng
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Hongyu Li
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Haiyan Zhang
- Department of Orthopedics, Orthopedic Hospital of Guangdong Province, Academy of Orthopedics·Guangdong Province, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.,The Third School of Clinical Medicine, Southern Medical University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Guangzhou, China.,Department of Joint Surgery, Center for Orthopaedic Surgery, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Chenglong Pan
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University Guangdong Province, Guangzhou, China
| | - Daozhang Cai
- Department of Orthopedics, Orthopedic Hospital of Guangdong Province, Academy of Orthopedics·Guangdong Province, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.,The Third School of Clinical Medicine, Southern Medical University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, Guangzhou, China.,Department of Joint Surgery, Center for Orthopaedic Surgery, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Xiao Yu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China.,Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University Guangdong Province, Guangzhou, China.,Guangdong Provincial Key Lab of Single Cell Technology and Application, Southern Medical University, Guangzhou, China
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9
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Muangsiri P, Tanjapatkul R, Sriswadpong P, Jomkoh P, Jirawatnotai S. Indocyanine Green Fluorescence Angiography of the Transverse Cervical Arterial Supply to Clavicle Flaps: An Anatomical Study. Otolaryngol Head Neck Surg 2021; 166:68-73. [PMID: 33784191 DOI: 10.1177/01945998211000432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To describe the anatomy of the transverse cervical artery and to prove its perfusion to the clavicle using indocyanine green fluorescence angiography as an alternative vascularized bone for head and neck reconstruction. STUDY DESIGN Cadaveric dissection. SETTING Anatomy lab. METHODS Twenty-two necks and shoulders from 11 fresh-frozen cadavers were dissected. The transverse cervical artery diameter, length, emerging point, and the length of clavicle segment harvested were described. Photographic and near-infrared video recordings of the bone's medial and longitudinal cut surfaces were taken prior to, during, and after indocyanine green injection. RESULTS The transverse cervical artery originated from the thyrocervical trunk and emerged at the level of the medial one-third of the clavicle in 22 of 22 (100%) specimens. The average length of the pedicle was 3.6 cm (range, 2.2-4.4 cm), and the mean diameter was 2.5 mm (range, 1.8-3.4 mm). The harvested bone had a mean length of 5.1 cm (range, 4.3-5.8 cm). After injecting the indocyanine green, 22 of 22 (100%) specimens showed enhancement in the periosteum, bony cortex, and medulla. CONCLUSION The middle third of the clavicle can be reliably harvested as a vascularized bone with its perfusion solely from the transverse cervical artery pedicle, as shown by the near-infrared fluorescence imaging. The pedicle was sizable and constant in origin.
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Affiliation(s)
- Pichtat Muangsiri
- Department of Plastic and Reconstructive Surgery, Lerdsin Hospital, Bangkok, Thailand
| | - Rungkit Tanjapatkul
- Department of Plastic and Reconstructive Surgery, Lerdsin Hospital, Bangkok, Thailand
| | - Papat Sriswadpong
- Department of Plastic and Reconstructive Surgery, Lerdsin Hospital, Bangkok, Thailand
| | - Pojanan Jomkoh
- Department of Plastic and Reconstructive Surgery, Lerdsin Hospital, Bangkok, Thailand
| | - Supasid Jirawatnotai
- Department of Plastic and Reconstructive Surgery, Lerdsin Hospital, Bangkok, Thailand
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10
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Opportunistic osteoporosis screening in multi-detector CT images using deep convolutional neural networks. Eur Radiol 2020; 31:1831-1842. [PMID: 33001308 DOI: 10.1007/s00330-020-07312-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/29/2020] [Accepted: 09/17/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To explore the application of deep learning in patients with primary osteoporosis, and to develop a fully automatic method based on deep convolutional neural network (DCNN) for vertebral body segmentation and bone mineral density (BMD) calculation in CT images. MATERIALS AND METHODS A total of 1449 patients were used for experiments and analysis in this retrospective study, who underwent spinal or abdominal CT scans for other indications between March 2018 and May 2020. All data was gathered from three different CT vendors. Among them, 586 cases were used for training, and other 863 cases were used for testing. A fully convolutional neural network, called U-Net, was employed for automated vertebral body segmentation. The manually sketched region of vertebral body was used as the ground truth for comparison. A convolutional neural network, called DenseNet-121, was applied for BMD calculation. The values post-processed by quantitative computed tomography (QCT) were identified as the standards for analysis. RESULTS Based on the diversity of CT vendors, all testing cases were split into three testing cohorts: Test set 1 (n = 463), test set 2 (n = 200), and test set 3 (n = 200). Automated segmentation correlated well with manual segmentation regarding four lumbar vertebral bodies (L1-L4): the minimum average dice coefficients for three testing sets were 0.823, 0.786, and 0.782, respectively. For testing sets from different vendors, the average BMDs calculated by automated regression showed high correlation (r > 0.98) and agreement with those derived from QCT. CONCLUSIONS A deep learning-based method could achieve fully automatic identification of osteoporosis, osteopenia, and normal bone mineral density in CT images. KEY POINTS • Deep learning can perform accurate fully automated segmentation of lumbar vertebral body in CT images. • The average BMDs obtained by deep learning highly correlates with ones derived from QCT. • The deep learning-based method could be helpful for clinicians in opportunistic osteoporosis screening in spinal or abdominal CT scans.
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11
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Fathi Kazerooni A, Pozo JM, McCloskey EV, Saligheh Rad H, Frangi AF. Diffusion MRI for Assessment of Bone Quality; A Review of Findings in Healthy Aging and Osteoporosis. J Magn Reson Imaging 2020; 51:975-992. [PMID: 31709670 PMCID: PMC7078977 DOI: 10.1002/jmri.26973] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/25/2019] [Accepted: 09/26/2019] [Indexed: 01/13/2023] Open
Abstract
Diffusion MRI (dMRI) is a growing imaging technique with the potential to provide biomarkers of tissue variation, such as cellular density, tissue anisotropy, and microvascular perfusion. However, the role of dMRI in characterizing different aspects of bone quality, especially in aging and osteoporosis, has not yet been fully established, particularly in clinical applications. The reason lies in the complications accompanied with implementation of dMRI in assessment of human bone structure, in terms of acquisition and quantification. Bone is a composite tissue comprising different elements, each contributing to the overall quality and functional competence of bone. As diffusion is a critical biophysical process in biological tissues, early changes of tissue microstructure and function can affect diffusive properties of the tissue. While there are multiple MRI methods to detect variations of individual properties of bone quality due to aging and osteoporosis, dMRI has potential to serve as a superior method for characterizing different aspects of bone quality within the same framework but with higher sensitivity to early alterations. This is mainly because several properties of the tissue including directionality and anisotropy of trabecular bone and cell density can be collected using only dMRI. In this review article, we first describe components of human bone that can be potentially detected by their diffusivity properties and contribute to variations in bone quality during aging and osteoporosis. Then we discuss considerations and challenges of dMRI in bone imaging, current status, and suggestions for development of dMRI in research studies and clinics to segregate different contributing components of bone quality in an integrated acquisition. Level of Evidence: 5 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:975-992.
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Affiliation(s)
- Anahita Fathi Kazerooni
- Department of Radiology, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Jose M. Pozo
- CISTIB Centre for Computational Imaging & Simulation Technologies in Biomedicine, School of Computing and School of MedicineUniversity of LeedsLeedsUK
| | - Eugene Vincent McCloskey
- Department of Oncology & Metabolism, Mellanby Centre for Bone Research, Centre for Integrated research in Musculoskeletal AgeingUniversity of SheffieldSheffieldUK
| | - Hamidreza Saligheh Rad
- Quantitative MR Imaging and Spectroscopy Group, Research Center for Molecular and Cellular ImagingTehran University of Medical SciencesTehranIran
- Department of Medical Physics and Biomedical EngineeringTehran University of Medical SciencesTehranIran
| | - Alejandro F. Frangi
- CISTIB Centre for Computational Imaging & Simulation Technologies in Biomedicine, School of Computing and School of MedicineUniversity of LeedsLeedsUK
- LICAMM Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
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12
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Abstract
BACKGROUND Extracorporeal shock wave therapy (ESWT) has shown benefits in patients with nonunion or delayed bone healing, pseudarthrosis, and avascular necrosis of bone. Until now, these effects were explained by the release of growth factors, activation of cells, and microfractures occurring after ESWT. Microcirculation is an important factor in bone healing and may be compromised in fractured scaphoids because its blood supply comes from the distal end. Due to this perfusion pattern, the scaphoid bone is prone to nonunion after fracture. The ability of ESWT to enhance microcirculation parameters in soft tissue was of interest to determine if it improves microcirculation in the scaphoid. QUESTIONS/PURPOSES (1) Does capillary blood flow increase after a single session of ESWT in the scaphoid? (2) Do oxygen saturation in the bone and postcapillary venous filling pressure increase after a single session of ESWT in the scaphoid? METHODS ESWT (0.3 mJ/mm, 8Hz, 1000 impulses) was applied to the intact scaphoid of 20 volunteers who were without wrist pain and without any important metabolic disorders. Mean age was 43 ± 14 years, 12 men and eight women (40% of total). Volunteers were recruited from January 2017 to May 2017. No anesthetic was given before application of ESWT. An innovative probe designed for measurements in bone by compressing soft tissue and combining laser-Doppler flowmetry and spectrophotometry was used to noninvasively measure parameters of microcirculation in the scaphoid. Blood flow, oxygenation, and venous filling pressure were assessed before and at 1, 2, 3, 5, 10, 15, 20, 25, and 30 minutes after ESWT application. Room temperature, humidity, ambient light and measuring sequences were kept consistent. A paired t-test was performed to compare experimental data with baseline (p < 0.05 taken as significant). RESULTS At baseline, capillary blood flow of the bone was 108 ± 46 arbitrary units (AUs) (86 to 130). After treatment with ESWT, it was 129 ± 44 AUs (106 to 150; p = 0.011, percentage change of 19 %) at 1 minute, 138 ± 46 AUs (116 to 160; p = 0.002, percentage change of 28%) at 2 minutes, 146 ± 54 AUs (121 to 171; p = 0.002, percentage change of 35%) at 3 minutes and 150 ± 52 AUs (126 to 174; p < 0.001, percentage change of 39%) at 5 minutes. It remained elevated until the end of the measuring period at 30 minutes after treatment at 141 ± 42 AUs (121 to 161; p = 0.002) versus baseline). Oxygen saturation and postcapillary venous filling pressure in bone showed no change, with the numbers available. CONCLUSIONS A single session of ESWT increased capillary blood flow in the scaphoid during measuring time of 30 minutes. Bone oxygenation and postcapillary venous filling pressure, however, did not change. Because increased oxygenation is needed for improved bone healing, it remains unclear if a sole increase in capillary blood flow can have clinical benefits. As the measuring period was limited to only 30 minutes, bone oxygenation and postcapillary filling pressure may subsequently show change only after the measuring-period ended. CLINICAL RELEVANCE Further studies need to evaluate if increased capillary blood flow can be sustained for longer periods and if bone oxygenation and postcapillary venous filling pressure remain unchanged even after prolonged or repetitive ESWT applications. Moreover, clinical studies must validate if increased microcirculation has a positive impact on bone healing and to determine if ESWT can be therapeutically useful on scaphoid fractures and nonunions.
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Hanne NJ, Easter ED, Cole JH. Minimally invasive laser Doppler flowmetry is suitable for serial bone perfusion measurements in mice. Bone Rep 2019; 11:100231. [PMID: 31867412 PMCID: PMC6900537 DOI: 10.1016/j.bonr.2019.100231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/17/2019] [Accepted: 11/18/2019] [Indexed: 01/02/2023] Open
Abstract
In vivo laser Doppler flowmetry (LDF) has previously been used to quantify blood perfusion accurately at a single timepoint in the murine tibial metaphysis. However, this procedure entailed substantial disruption to soft tissues overlying the bone and caused notable localized inflammation for several weeks after the procedure, impeding serial measurements in the same mouse. In this study, we tested a less invasive technique to measure perfusion in the tibia with LDF and determined that it can be used serially in the same mouse without causing signs of inflammation or gait perturbations. Twenty 14-week-old C57Bl/6J mice were evenly divided into groups that either had daily treadmill exercise or remained sedentary. Within these activity groups, mice were evenly subdivided into groups that received LDF measurements either weekly or only once at the study endpoint. Bone perfusion was measured with LDF in the anteromedial region of the right tibial metaphysis. Serum concentrations of interleukin 6, incision site wound area, and interlimb coordination during gait were measured weekly for four weeks. Tibial perfusion did not differ significantly between exercise and sedentary groups within the weekly or endpoint-only LDF groups at any timepoint. Perfusion was significantly increased in the third week in the weekly LDF group relative to measurements in the second and fourth weeks. Ligation of the femoral artery caused consistent, rapid reductions in tibial perfusion, validating that LDF is sensitive to changes in tibial blood supply. Weekly LDF procedures did not adversely affect gait, as interlimb coordination during treadmill locomotion was similar between weekly and endpoint-only LDF groups at every timepoint. Images of the incision site show wound closure within one week, and serum concentrations of interleukin 6 were not significantly different between weekly and endpoint-only groups. Together, these findings demonstrate that our minimally invasive LDF technique is suitable for serial in vivo measurements of intraosseous blood perfusion without inducing localized inflammation or negatively affecting gait patterns in mice.
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Affiliation(s)
- Nicholas J Hanne
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA, and North Carolina State University, Raleigh, NC, USA
| | - Elizabeth D Easter
- Materials Science and Engineering, North Carolina State University, Raleigh, NC, USA
| | - Jacqueline H Cole
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA, and North Carolina State University, Raleigh, NC, USA
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14
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Dyke JP, Garfinkel JH, Volpert L, Sanders A, Newcomer M, Dutruel SP, Sofka CM, Ellis SJ, Demetracopoulos CA. Imaging of Bone Perfusion and Metabolism in Subjects Undergoing Total Ankle Arthroplasty Using 18F-Fluoride Positron Emission Tomography. Foot Ankle Int 2019; 40:1351-1357. [PMID: 31597454 DOI: 10.1177/1071100719882717] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Total ankle arthroplasty (TAA) continues to exhibit a relatively high incidence of complications and need for revision surgery compared to knee and hip arthroplasty. One common mode of failure in TAA is talar component subsidence. This may be caused by disruption in the talar blood supply related to the operative technique. The purpose of this study was to quantify changes in talar bone perfusion and turnover before and after TAA with the INBONE II system using 18F-fluoride positron emission tomography / computed tomography (PET/CT). METHODS Nine subjects (5 M/4 F) aged 68.9 ± 8.2 years were enrolled for 18F-fluoride PET/CT imaging before and 3 months after TAA. Regions of interest (ROI) were placed on the postoperative CT images in the body of the talus beneath the talar component and overlaid on the fused static PET images. Standard uptake values (SUVs) along with dynamic K1 (bone blood flow) and ki (bone metabolism or osteoblastic turnover) were calculated. RESULTS The SUV underneath the talar component compared to that measured at baseline before surgery was 1.93 ± 0.29 preoperatively vs 2.47 ± 0.37 postoperatively (P > .05). K1 was 0.84 ± 0.16 mL/min/mL preoperatively vs 1.51 ± 0.23 mL/min/mL postoperatively (P = .026). ki was constant at 0.09 ± 0.03 mL/min/mL preoperatively vs 0.12 ± 0.03 mL/min/mL postoperatively (P > .05). CONCLUSION Our study was the first to link 18F-fluoride PET/CT with pre-post evaluation of total ankle replacements. The study quantified perfusion within the talus beneath the TAA implant supporting the hypothesis that perfusion of the talus remained intact after surgery. LEVEL OF EVIDENCE Level II, prospective cohort study with development of diagnostic criteria.
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Affiliation(s)
- Jonathan P Dyke
- Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, USA
| | | | - Lauren Volpert
- Foot and Ankle Service, Hospital for Special Surgery, New York, NY, USA
| | - Austin Sanders
- Foot and Ankle Service, Hospital for Special Surgery, New York, NY, USA
| | - Meghan Newcomer
- Foot and Ankle Service, Hospital for Special Surgery, New York, NY, USA
| | | | - Carolyn M Sofka
- Department of Radiology, Hospital for Special Surgery, New York, NY, USA
| | - Scott J Ellis
- Foot and Ankle Service, Hospital for Special Surgery, New York, NY, USA
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15
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Wan L, Wu M, Sheth V, Shao H, Jang H, Bydder G, Du J. Evaluation of cortical bone perfusion using dynamic contrast enhanced ultrashort echo time imaging: a feasibility study. Quant Imaging Med Surg 2019; 9:1383-1393. [PMID: 31559167 DOI: 10.21037/qims.2019.08.05] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) has been used to study perfusion in a wide variety of soft tissues including the bone marrow. Study of perfusion in hard tissues such as cortical bone has been much more limited because of the lack of detectable MR signal from them using conventional pulse sequences. However, two-dimensional (2D) ultrashort echo time (UTE) sequences detect signal from cortical bone and allow fast imaging of this tissue. In addition, adiabatic 2D inversion recovery UTE (IR-UTE) sequences can provide excellent signal suppression of soft tissues, such as muscle and marrow, and allow cortical bone to be seen with high contrast and reduced artefacts. We aimed to assess the feasibility of using 2D UTE and 2D IR-UTE sequences to perform DCE-MRI in the cortical bone of rabbits and human volunteers. Methods Cortical bone perfusion was studied in rabbits (n=12) and human volunteers (n=3) using 2D UTE and 2D IR-UTE sequences on a clinical 3T scanner. Dynamic data with an in-plane resolution of ~0.5×0.5 mm2, single slice thickness of 3 mm for rabbits and 10 mm for human volunteers, and temporal resolution of 23 s for 2D UTE imaging of rabbits, 28 s for 2D UTE imaging of human volunteers, and 60 s for 2D IR-UTE imaging of both the rabbits and human volunteers were acquired before and after the injection of a Gd contrast agent (Gd-BOPTA: Multihance; Bracco Imaging SpA, Milan, Italy). The dose was 0.06 mmol/kg for rabbits and 0.2 mmol/kg for human subjects. Kinetic analyses based on the Brix model, as well as simple calculations of maximum enhancement (ME) and enhancement slope (ES), were performed. Results The 12 rabbits showed a mean Ktrans of 0.36±0.07 min-1, Kep of 8.42±3.17 min-1, ME of 28.30±6.83, ES of 0.35±0.18 for the femur with the 2D UTE sequence, and a mean Ktrans of 0.45±0.10 min-1, Kep of 9.80±0.50 min-1, ME of 48.84±12.12, and ES of 0.69±0.27 for the femur with the 2D IR-UTE sequence. Lower ME and ES values were observed in the tibial midshaft of healthy human volunteers compared to rabbits. Conclusions These results show that 2D UTE and 2D IR-UTE sequences are capable of detecting dynamic contrast enhancement in cortical bone in both rabbits and healthy human volunteers. Clinical studies with these techniques are likely to be feasible.
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Affiliation(s)
- Lidi Wan
- Department of Radiology, University of California, San Diego, CA, USA
| | - Mei Wu
- Department of Radiology, University of California, San Diego, CA, USA
| | - Vipul Sheth
- Department of Radiology, University of California, San Diego, CA, USA
| | - Hongda Shao
- Department of Radiology, University of California, San Diego, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA, USA
| | - Graeme Bydder
- Department of Radiology, University of California, San Diego, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, USA
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Elliott JT, Jiang S, Pogue BW, Gitajn IL. Bone-specific kinetic model to quantify periosteal and endosteal blood flow using indocyanine green in fluorescence guided orthopedic surgery. JOURNAL OF BIOPHOTONICS 2019; 12:e201800427. [PMID: 30963727 PMCID: PMC7331892 DOI: 10.1002/jbio.201800427] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 03/10/2019] [Accepted: 04/04/2019] [Indexed: 05/22/2023]
Abstract
This letter describes a hybrid plug/compartment (HyPC) kinetic model to fit dynamic indocyanine green fluorescence data acquired in a porcine model of long bone traumatic fracture. Parametric images of periosteal blood flow, endosteal blood flow, total bone blood flow and fraction of endosteal-to-periosteal flow were obtained by applying the HyPC model on a pixel-by-pixel basis. Intraoperative discrimination between healthy and damaged bone could facilitate debridement reducing post-operative complications from non-union and infection. The ability to quantify periosteal and endosteal blood flow could inform nail vs. plate-and-screw decisions to avoid further compromising cortical blood supply.
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Affiliation(s)
- Jonathan T. Elliott
- Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH
- Thayer School of Engineering at Dartmouth, Hanover, NH
| | - Shudong Jiang
- Thayer School of Engineering at Dartmouth, Hanover, NH
| | | | - Ida Leah Gitajn
- Department of Orthopaedics and Sports Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH
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17
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Increase of Glucose Uptake in Human Bone Marrow With Increasing Exercise Intensity. Int J Sport Nutr Exerc Metab 2019; 29:254-258. [DOI: 10.1123/ijsnem.2018-0094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Human bone marrow is a metabolically active tissue that responds to acute low-intensity exercise by having increased glucose uptake (GU). Here, the authors studied whether bone marrow GU increases more with increased exercise intensities. Femoral bone marrow GU was measured using positron emission tomography and [18F]-fluorodeoxyglucose in six healthy young men during cycling at intensities of 30% (low), 55% (moderate), and 75% (high) of maximal oxygen consumption on three separate days. Bone marrow GU at low was 17.2 µmol·kg−1·min−1 (range 9.0–25.4) and increased significantly (p = .003) at moderate (31.2 µmol·kg−1·min−1, 22.9–39.4) but was not significant from moderate to high (37.4 µmol·kg−1·min−1, 29.0–45.7, p = .26). Furthermore, the ratio between bone and muscle GU decreased from low to moderate exercise intensity (p < .01) but not (p = .99) from moderate to high exercise intensity. In conclusion, these results show that although the increase is not as large as observed in exercising skeletal muscle, GU in femoral bone marrow increases with increasing exercise intensity at least from low- to moderate-intensity effort, which may be important for bone and whole-body metabolic health.
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18
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Meertens R, Casanova F, Knapp KM, Thorn C, Strain WD. Use of near-infrared systems for investigations of hemodynamics in human in vivo bone tissue: A systematic review. J Orthop Res 2018; 36:2595-2603. [PMID: 29727022 DOI: 10.1002/jor.24035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 04/27/2018] [Indexed: 02/04/2023]
Abstract
A range of technologies using near infrared (NIR) light have shown promise at providing real time measurements of hemodynamic markers in bone tissue in vivo, an exciting prospect given existing difficulties in measuring hemodynamics in bone tissue. This systematic review aimed to evaluate the evidence for this potential use of NIR systems, establishing their potential as a research tool in this field. Major electronic databases including MEDLINE and EMBASE were searched using pre-planned search strategies with broad scope for any in vivo use of NIR technologies in human bone tissue. Following identification of studies by title and abstract screening, full text inclusion was determined by double blind assessment using predefined criteria. Full text studies for inclusion were data extracted using a predesigned proforma and quality assessed. Narrative synthesis was appropriate given the wide heterogeneity of included studies. Eighty-eight full text studies fulfilled the inclusion criteria, 57 addressing laser Doppler flowmetry (56 intra-operatively), 21 near infrared spectroscopy, and 10 photoplethysmography. The heterogeneity of the methodologies included differing hemodynamic markers, measurement protocols, anatomical locations, and research applications, making meaningful direct comparisons impossible. Further, studies were often limited by small sample sizes with potential selection biases, detection biases, and wide variability in results between participants. Despite promising potential in the use of NIR light to interrogate bone circulation, the application of NIR systems in bone requires rigorous assessment of the reproducibility of potential hemodynamic markers and further validation of these markers against alternative physiologically relevant reference standards. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2595-2603, 2018.
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Affiliation(s)
- Robert Meertens
- Medical Imaging, University of Exeter Medical School, South Cloisters, St Luke's Campus, Heavitree Road, Exeter EX2 1LU, United Kingdom
| | - Francesco Casanova
- Diabetes and Vascular Research Centre, University of Exeter Medical School and National Institute of Health Research Exeter Clinical Research Facility, Barrack Rd, Exeter EX2 5DW, United Kingdom
| | - Karen M Knapp
- Medical Imaging, University of Exeter Medical School, South Cloisters, St Luke's Campus, Heavitree Road, Exeter EX2 1LU, United Kingdom
| | - Clare Thorn
- Diabetes and Vascular Research Centre, University of Exeter Medical School and National Institute of Health Research Exeter Clinical Research Facility, Barrack Rd, Exeter EX2 5DW, United Kingdom
| | - William David Strain
- Diabetes and Vascular Research Centre, University of Exeter Medical School and National Institute of Health Research Exeter Clinical Research Facility, Barrack Rd, Exeter EX2 5DW, United Kingdom
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19
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van der Heijden RA, Poot DHJ, Ekinci M, Kotek G, van Veldhoven PLJ, Klein S, Verhaar JAN, Krestin GP, Bierma-Zeinstra SMA, van Middelkoop M, Oei EHG. Blood perfusion of patellar bone measured by dynamic contrast-enhanced MRI in patients with patellofemoral pain: A case-control study. J Magn Reson Imaging 2018; 48:1344-1350. [PMID: 29734499 PMCID: PMC6221059 DOI: 10.1002/jmri.26174] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 04/16/2018] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Altered perfusion might play an important role in the pathophysiology of patellofemoral pain (PFP), a common knee complaint with unclear pathophysiology. PURPOSE To investigate differences in dynamic contrast-enhanced (DCE)-MRI perfusion parameters between patients with PFP and healthy control subjects. POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODEL Thirty-five adult patients with PFP and 44 healthy adult control subjects. FIELD STRENGTH/SEQUENCE 3T DCE-MRI consisting of a sagittal, anterior-posterior, frequency-encoded, fat-suppressed 3D spoiled gradient-echo sequence with intravenous contrast administration. ASSESSMENT Patellar bone volumes of interest (VOIs) were delineated by a blinded observer. Quantitative perfusion parameters (kep and ktrans ) were calculated from motion-compensated DCE-MRI data by fitting Tofts' model. Weighted mean and unweighted median values of kep and ktrans were computed within the patellar bone VOIs. STATISTICAL TESTS Differences in patellar bone perfusion parameters were compared between groups by linear regression analyses, adjusted for confounders. RESULTS Mean differences of weighted mean and unweighted median were 0.0039 (95% confidence interval [CI] -0.0013; 0.0091) and 0.0052 (95% CI -0.0078; 0.018) for ktrans , and 0.046 (95% CI -0.021; 0.11) and 0.069 (95% CI -0.017; 0.15) for kep , respectively. All perfusion parameters were not significantly different between groups (P-values: 0.32; 0.47 for ktrans , and 0.24; 0.15) for kep . However, a significant difference in variance between populations was observed for ktrans (P-value 0.007). DATA CONCLUSION Higher patellar bone perfusion parameters were found in patients with PFP when compared to healthy control subjects, but these differences were not statistically significant. This result, and the observed significant difference in ktrans variance, warrant further research. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1344-1350.
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Affiliation(s)
- Rianne A van der Heijden
- Department of General Practice, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.,Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Dirk H J Poot
- Biomedical Imaging Group Rotterdam, Departments of Medical Informatics & Radiology, Erasmus MC, Rotterdam, The Netherlands.,Quantitative Imaging, Department of Imaging Physics, TU Delft, Delft, The Netherlands
| | - Melek Ekinci
- Department of General Practice, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Gyula Kotek
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | | | - Stefan Klein
- Biomedical Imaging Group Rotterdam, Departments of Medical Informatics & Radiology, Erasmus MC, Rotterdam, The Netherlands
| | - Jan A N Verhaar
- Department of Orthopedics Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Gabriel P Krestin
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Sita M A Bierma-Zeinstra
- Department of General Practice, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.,Department of Orthopedics Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Marienke van Middelkoop
- Department of General Practice, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Edwin H G Oei
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
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20
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Lu J, Zhang H, Cai D, Zeng C, Lai P, Shao Y, Fang H, Li D, Ouyang J, Zhao C, Xie D, Huang B, Yang J, Jiang Y, Bai X. Positive-Feedback Regulation of Subchondral H-Type Vessel Formation by Chondrocyte Promotes Osteoarthritis Development in Mice. J Bone Miner Res 2018; 33:909-920. [PMID: 29329496 DOI: 10.1002/jbmr.3388] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Revised: 01/02/2018] [Accepted: 01/03/2018] [Indexed: 01/01/2023]
Abstract
Vascular-invasion-mediated interactions between activated articular chondrocytes and subchondral bone are essential for osteoarthritis (OA) development. Here, we determined the role of nutrient sensing mechanistic target of rapamycin complex 1 (mTORC1) signaling in the crosstalk across the bone cartilage interface and its regulatory mechanisms. Then mice with chondrocyte-specific mTORC1 activation (Tsc1 CKO and Tsc1 CKOER ) or inhibition (Raptor CKOER ) and their littermate controls were subjected to OA induced by destabilization of the medial meniscus (DMM) or not. DMM or Tsc1 CKO mice were treated with bevacizumab, a vascular endothelial growth factor (VEGF)-A antibody that blocks angiogenesis. Articular cartilage degeneration was evaluated using the Osteoarthritis Research Society International score. Immunostaining and Western blotting were conducted to detect H-type vessels and protein levels in mice. Primary chondrocytes from mutant mice and ADTC5 cells were treated with interleukin-1β to investigate the role of chondrocyte mTORC1 in VEGF-A secretion and in vitro vascular formation. Clearly, H-type vessels were increased in subchondral bone in DMM-induced OA and aged mice. Cartilage mTORC1 activation stimulated VEGF-A production in articular chondrocyte and H-type vessel formation in subchondral bone. Chondrocyte mTORC1 promoted OA partially through formation of VEGF-A-stimulated subchondral H-type vessels. In particular, vascular-derived nutrients activated chondrocyte mTORC1, and stimulated chondrocyte activation and production of VEGF, resulting in further angiogenesis in subchondral bone. Thus a positive-feedback regulation of H-type vessel formation in subchondral bone by articular chondrocyte nutrient-sensing mTORC1 signaling is essential for the pathogenesis and progression of OA. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Jiansen Lu
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University.,State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Haiyan Zhang
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Daozhang Cai
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Chun Zeng
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Pinglin Lai
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Yan Shao
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University.,State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Hang Fang
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Delong Li
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University.,State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Jiayao Ouyang
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University.,State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Chang Zhao
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Denghui Xie
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Bin Huang
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University
| | - Jian Yang
- Department of Biomedical Engineering, Materials Research Institutes, The Huck Institutes of The Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Yu Jiang
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Xiaochun Bai
- Department of Orthopedics, Academy of Orthopedics, Guangdong Province, Orthopedic Hospital of Guangdong Province, The Third Affiliated Hospital of Southern Medical University.,State Key Laboratory of Organ Failure Research, Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
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Abstract
PURPOSE OF REVIEW Solute transport in the lacunar-canalicular system (LCS) plays important roles in osteocyte metabolism and cell-cell signaling. This review will summarize recent studies that establish pericellular matrix (PCM), discovered inside the LCS, as a crucial regulator of solute transport in bone. RECENT FINDINGS Utilizing confocal imaging and mathematical modeling, recent studies successfully quantified molecular diffusion and convection in the LCS as well as the size-dependent sieving effects of the PCM, leading to the quantification of the effective PCM fiber spacing (10 to 17 nm) in murine adult bones. Perlecan/HSPG2, a large linear proteoglycan, was identified to be an essential PCM component. The PCM-filled LCS is bone's chromatographic column, where fluid/solute transport to and from the osteocytes is regulated. The chemical composition, deposition rate, and turnover rate of the osteocyte PCM should be further defined to better understand osteocyte physiology and bone metabolism.
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Affiliation(s)
- Liyun Wang
- Center for Biomechanical Research, Department of Mechanical Engineering, University of Delaware, 130 Academy Street, Newark, DE, 19716, USA.
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22
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Serrat MA, Ion G. Imaging IGF-I uptake in growth plate cartilage using in vivo multiphoton microscopy. J Appl Physiol (1985) 2017; 123:1101-1109. [PMID: 28798204 DOI: 10.1152/japplphysiol.00645.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/07/2017] [Accepted: 08/08/2017] [Indexed: 12/27/2022] Open
Abstract
Bones elongate through endochondral ossification in cartilaginous growth plates located at ends of primary long bones. Linear growth ensues from a cascade of biochemical signals initiated by actions of systemic and local regulators on growth plate chondrocytes. Although cellular processes are well defined, there is a fundamental gap in understanding how growth regulators are physically transported from surrounding blood vessels into and through dense, avascular cartilage matrix. Intravital imaging using in vivo multiphoton microscopy is one promising strategy to overcome this barrier by quantitatively tracking molecular delivery to cartilage from the vasculature in real time. We previously used in vivo multiphoton imaging to show that hindlimb heating increases vascular access of large molecules to growth plates using 10-, 40-, and 70-kDa dextran tracers. To comparatively evaluate transport of similarly sized physiological regulators, we developed and validated methods for measuring uptake of biologically active IGF-I into proximal tibial growth plates of live 5-wk-old mice. We demonstrate that fluorescently labeled IGF-I (8.2 kDa) is readily taken up in the growth plate and localizes to chondrocytes. Bioactivity tests performed on cultured metatarsal bones confirmed that the labeled protein is functional, assessed by phosphorylation of its signaling kinase, Akt. This methodology, which can be broadly applied to many different proteins and tissues, is relevant for understanding factors that affect delivery of biologically relevant molecules to the skeleton in real time. Results may lead to the development of drug-targeting strategies to treat a wide range of bone and cartilage pathologies.NEW & NOTEWORTHY This paper describes and validates a novel method for imaging transport of biologically active, fluorescently labeled IGF-I into skeletal growth plates of live mice using multiphoton microscopy. Cellular patterns of fluorescence in the growth plate were completely distinct from our prior publications using biologically inert probes, demonstrating for the first time in vivo localization of IGF-I in chondrocytes and perichondrium. These results form important groundwork for future studies aimed at targeting therapeutics into growth plates.
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Affiliation(s)
- Maria A Serrat
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Gabriela Ion
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
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Contribution of Circulatory Disturbances in Subchondral Bone to the Pathophysiology of Osteoarthritis. Curr Rheumatol Rep 2017; 19:49. [DOI: 10.1007/s11926-017-0660-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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24
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Poot DHJ, van der Heijden RA, van Middelkoop M, Oei EHG, Klein S. Dynamic contrast-enhanced MRI of the patellar bone: How to quantify perfusion. J Magn Reson Imaging 2017; 47:848-858. [PMID: 28707311 PMCID: PMC5836942 DOI: 10.1002/jmri.25817] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/29/2017] [Indexed: 12/17/2022] Open
Abstract
Purpose To identify the optimal combination of pharmacokinetic model and arterial input function (AIF) for quantitative analysis of blood perfusion in the patellar bone using dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI). Materials and Methods This method design study used a random subset of five control subjects from an Institutional Review Board (IRB)‐approved case–control study into patellofemoral pain, scanned on a 3T MR system with a contrast‐enhanced time‐resolved imaging of contrast kinetics (TRICKS) sequence. We systematically investigated the reproducibility of pharmacokinetic parameters for all combinations of Orton and Parker AIF models with Tofts, Extended Tofts (ETofts), and Brix pharmacokinetic models. Furthermore, we evaluated if the AIF should use literature parameters, be subject‐specific, or group‐specific. Model selection was based on the goodness‐of‐fit and the coefficient of variation of the pharmacokinetic parameters inside the patella. This extends previous studies that were not focused on the patella and did not evaluate as many combinations of arterial and pharmacokinetic models. Results The vascular component in the ETofts model could not reliably be recovered (coefficient of variation [CV] of vp >50%) and the Brix model parameters showed high variability of up to 20% for kel across good AIF models. Compared to group‐specific AIF, the subject‐specific AIF's mostly had higher residual. The best reproducibility and goodness‐of‐fit were obtained by combining Tofts' pharmacokinetic model with the group‐specific Parker AIF. Conclusion We identified several good combinations of pharmacokinetic models and AIF for quantitative analysis of perfusion in the patellar bone. The recommended combination is Tofts pharmacokinetic model combined with a group‐specific Parker AIF model. Level of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:848–858.
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Affiliation(s)
- Dirk H J Poot
- Biomedical Imaging Group Rotterdam, Departments of Medical Informatics & Radiology, Erasmus MC, Rotterdam, The Netherlands.,Quantitative Imaging, Department of Imaging Physics, Delft University of Technology, Delft, The Netherlands
| | - Rianne A van der Heijden
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands.,Department of General Practice, Erasmus MC, Rotterdam, The Netherlands
| | | | - Edwin H G Oei
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Stefan Klein
- Biomedical Imaging Group Rotterdam, Departments of Medical Informatics & Radiology, Erasmus MC, Rotterdam, The Netherlands
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25
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Kumar KA, Peck KK, Karimi S, Lis E, Holodny AI, Bilsky MH, Yamada Y. A Pilot Study Evaluating the Use of Dynamic Contrast-Enhanced Perfusion MRI to Predict Local Recurrence After Radiosurgery on Spinal Metastases. Technol Cancer Res Treat 2017; 16:857-865. [PMID: 28449626 PMCID: PMC5762041 DOI: 10.1177/1533034617705715] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose: Dynamic contrast-enhanced magnetic resonance imaging offers noninvasive characterization of the vascular microenvironment and hemodynamics. Stereotactic radiosurgery, or stereotactic body radiation therapy, engages a vascular component of the tumor response which may be detectable using dynamic contrast-enhanced magnetic resonance imaging. The purpose of this study is to examine whether dynamic contrast-enhanced magnetic resonance imaging can be used to predict local tumor recurrence in patients with spinal bone metastases who undergo high-dose radiotherapy with stereotactic radiosurgery. Materials and Methods: We conducted a study of 30 patients with spinal metastases who underwent dynamic contrast-enhanced magnetic resonance imaging before and after radiotherapy. Twenty patients received single-fraction stereotactic radiosurgery (24 Gy), while 10 received hypofractionated stereotactic radiosurgery (3-5 fractions, 27-30 Gy total). Kaplan-Meier analysis was used to estimate the actuarial local recurrence rates. Two perfusion parameters (Ktrans: permeability and Vp: plasma volume) were measured for each metastasis. Percentage change in parameter values from pre- to posttreatment was calculated and compared. Results: At 20-month median follow-up, 5 of the 30 patients had pathological evidence of local recurrence. One- and 3-year actuarial local recurrence rates were 24% and 44% for the hypofractionated stereotactic radiosurgery cohort versus 5% and 16% for the single-fraction stereotactic radiosurgery cohort (P = .20). The average change in Vp and Ktrans for patients without local recurrence versus those with local recurrence was −76% and −66% versus +28% and −14% (P < .01 for both). With a cutoff point of −20%, Vp had a sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 98%, 91%, and 100%, respectively, for the detection of local recurrence following high-dose radiotherapy. Using this definition, dynamic contrast-enhanced magnetic resonance imaging identified local recurrence up to 18 months (mean [standard deviation], 6.6 [6.8] months) earlier than standard magnetic resonance imaging. Conclusions: We demonstrated that changes in perfusion parameters, particularly Vp, after high-dose radiotherapy to spinal bone metastases were predictive of local tumor recurrence. These changes predicted local recurrence on average >6 months earlier than standard imaging did.
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Affiliation(s)
- Kiran A Kumar
- Department of Radiation Oncology, Stanford University, Stanford, CA, USA
| | - Kyung K Peck
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Sasan Karimi
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Eric Lis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Andrei I Holodny
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Mark H Bilsky
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Yoshiya Yamada
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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26
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Cucchiarini M, de Girolamo L, Filardo G, Oliveira JM, Orth P, Pape D, Reboul P. Basic science of osteoarthritis. J Exp Orthop 2016; 3:22. [PMID: 27624438 PMCID: PMC5021646 DOI: 10.1186/s40634-016-0060-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 09/09/2016] [Indexed: 12/20/2022] Open
Abstract
Osteoarthritis (OA) is a prevalent, disabling disorder of the joints that affects a large population worldwide and for which there is no definitive cure. This review provides critical insights into the basic knowledge on OA that may lead to innovative end efficient new therapeutic regimens. While degradation of the articular cartilage is the hallmark of OA, with altered interactions between chondrocytes and compounds of the extracellular matrix, the subchondral bone has been also described as a key component of the disease, involving specific pathomechanisms controlling its initiation and progression. The identification of such events (and thus of possible targets for therapy) has been made possible by the availability of a number of animal models that aim at reproducing the human pathology, in particular large models of high tibial osteotomy (HTO). From a therapeutic point of view, mesenchymal stem cells (MSCs) represent a promising option for the treatment of OA and may be used concomitantly with functional substitutes integrating scaffolds and drugs/growth factors in tissue engineering setups. Altogether, these advances in the fundamental and experimental knowledge on OA may allow for the generation of improved, adapted therapeutic regimens to treat human OA.
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Affiliation(s)
- Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Kirrbergerstr. Bldg 37, D-66421, Homburg, Germany.
| | - Laura de Girolamo
- Orthopaedic Biotechnology Laboratory, Galeazzi Orthopaedic Institute, Milan, Italy
| | - Giuseppe Filardo
- Orthopaedic and Traumatologic I Clinic, Biomechanics Laboratory, Rizzoli Orthopaedic Institute, University of Bologna, Bologna, Italy
| | - J Miguel Oliveira
- 3B's Research Group - Biomaterials, Biodegradables and Biomimetics, Univ. Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark - Parque de Ciência e Tecnologia, Zona Industrial da Gandra, Barco GMR, Barco, Guimarães, Portugal
- ICVS/3B's - PT Government Associated Laboratory, Barco, Guimarães, Portugal
| | - Patrick Orth
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Kirrbergerstr. Bldg 37, D-66421, Homburg, Germany
- Department of Orthopaedic Surgery, Saarland University Medical Center and Saarland University, Homburg, Saar, Germany
| | - Dietrich Pape
- Department of Orthopaedic Surgery, Centre Hospitalier de Luxembourg, Luxembourg ville, Luxembourg
- Sports Medicine Research Laboratory, Public Research Centre for Health, Luxembourg, Centre Médical de la Fondation Norbert Metz, Luxembourg ville, Luxembourg
| | - Pascal Reboul
- UMR 7365 CNRS-Université de Lorraine, IMoPA, Biopôle de l'Université de Lorraine, Campus Biologie-Santé, Vandoeuvre-lès-Nancy, France
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Han S, Proctor AR, Vella JB, Benoit DSW, Choe R. Non-invasive diffuse correlation tomography reveals spatial and temporal blood flow differences in murine bone grafting approaches. BIOMEDICAL OPTICS EXPRESS 2016; 7:3262-3279. [PMID: 27699097 PMCID: PMC5030009 DOI: 10.1364/boe.7.003262] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 07/30/2016] [Accepted: 07/31/2016] [Indexed: 05/16/2023]
Abstract
Longitudinal blood flow during murine bone graft healing was monitored non-invasively using diffuse correlation tomography. The system utilized spatially dense data from a scanning set-up, non-linear reconstruction, and micro-CT anatomical information. Weekly in vivo measurements were performed. Blood flow changes in autografts, which heal successfully, were localized to graft regions and consistent across mice. Poor healing allografts showed heterogeneous blood flow elevation and high inter-subject variabilities. Allografts with tissue-engineered periosteum showed responses intermediate to both autografts and allografts, consistent with healing observed. These findings suggest that spatiotemporal blood flow changes can be utilized to differentiate the degree of bone graft healing.
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Affiliation(s)
- Songfeng Han
- Institute of Optics, University of Rochester, Rochester, NY 14627, USA
| | - Ashley R. Proctor
- Department of Biomedical Engineering, University of Rochester, Rochester, NY 14627, USA
| | - Joseph B. Vella
- Department of Biomedical Engineering, University of Rochester, Rochester, NY 14627, USA
- Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY 14642, USA
- Department of Otolaryngology-Head and Neck Surgery, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Danielle S. W. Benoit
- Department of Biomedical Engineering, University of Rochester, Rochester, NY 14627, USA
- Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY 14642, USA
- Department of Chemical Engineering, University of Rochester, Rochester, NY 14627, USA
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Regine Choe
- Department of Biomedical Engineering, University of Rochester, Rochester, NY 14627, USA
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY 14627, USA
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28
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Spratt DE, Perez JA, Leeman JE, Gerber NK, Folkert M, Taunk NK, Alektiar KM, Karimi S, Lyo JK, Tap WD, Bilsky MH, Laufer I, Yamada Y, Osborne JR. Early magnetic resonance imaging biomarkers to predict local control after high dose stereotactic body radiotherapy for patients with sarcoma spine metastases. Spine J 2016; 16:291-8. [PMID: 26325017 PMCID: PMC5665020 DOI: 10.1016/j.spinee.2015.08.041] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 07/08/2015] [Accepted: 08/22/2015] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Recent advances in image guidance and stereotactic body radiotherapy (SBRT) have resulted in unprecedented local control for spinal metastases of all histologies. However, little is known about early imaging biomarkers of local control. PURPOSE This study aimed to identify early magnetic resonance imaging (MRI) biomarkers to predict local control after SBRT for patients with sarcoma spine metastases. STUDY DESIGN/SETTING This study used a retrospective case series at a large tertiary cancer center. PATIENT SAMPLE From 2011 to 2014, 9 consecutive patients with 12 metastatic sarcoma lesions to the spine were treated with SBRT and underwent evaluation with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) both pre- and post-SBRT. OUTCOME MEASURE Changes in perfusion metrics, including the wash-in rate constant (Ktrans), plasma volume (Vp), composite multiparametric magnetic resonance imaging (mpMRI) score, bi-dimensional tumor size, and a graded response assessment were performed and correlated to local control. METHODS All measurements were independent and blinded by two neuroradiologists. R2 statistics were performed to document correlation, and two-tailed t tests were used to compare groups. p<.05 was deemed statistically significant. RESULTS The median time from SBRT until posttreatment MRI was 57 days. Local failure developed in one lesion (8.3%) 10 months after SBRT. The Vp mean, Ktrans mean, Vp max, and Ktrans max were significantly decreased post-SBRT as compared with pre-SBRT (58.7%, 63.2%, 59.0%, and 55.2%; all p-values <.05). Bi-dimensional tumor measurements demonstrated an average increase in size across the cohort, and 50%, 25%, and 25% of the treated lesions demonstrated features of "worsening," "no change," or "improvement," respectively, by both radiologists' graded impressions. There was good inter-reader reliability for both size and subjective disease response scores (R2=0.84). The mpMRI score had 100% accuracy in predicting local control at time of last follow-up. There was no apparent correlation with size changes compared with the mpMRI score change post-SBRT (R2=0.026). CONCLUSIONS We report the first analysis on the utility of DCE-MRI for metastatic sarcoma spine metastases treated with SBRT. We demonstrate that early assessment at 2 months post-SBRT using size and subjective neuroradiology impressions is insufficient to judge ultimate disease progression, and that a combination of perfusion parameters provides excellent correlation to local control.
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Affiliation(s)
- Daniel E. Spratt
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York,Corresponding author: Daniel E. Spratt, MD, Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 22, New York, NY 10065;
| | - Julio A. Perez
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Jonathan E. Leeman
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Naamit K. Gerber
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Michael Folkert
- Department of Radiation Oncology, UT Southwestern, Dallas, Texas,Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Neil K. Taunk
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Kaled M. Alektiar
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sasan Karimi
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - John K. Lyo
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - William D. Tap
- Department of Medical Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Mark H. Bilsky
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Ilya Laufer
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Yoshiya Yamada
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Joseph R. Osborne
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
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29
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Han S, Hoffman MD, Proctor AR, Vella JB, Mannoh EA, Barber NE, Kim HJ, Jung KW, Benoit DSW, Choe R. Non-Invasive Monitoring of Temporal and Spatial Blood Flow during Bone Graft Healing Using Diffuse Correlation Spectroscopy. PLoS One 2015; 10:e0143891. [PMID: 26625352 PMCID: PMC4666601 DOI: 10.1371/journal.pone.0143891] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/10/2015] [Indexed: 01/15/2023] Open
Abstract
Vascular infiltration and associated alterations in microvascular blood flow are critical for complete bone graft healing. Therefore, real-time, longitudinal measurement of blood flow has the potential to successfully predict graft healing outcomes. Herein, we non-invasively measure longitudinal blood flow changes in bone autografts and allografts using diffuse correlation spectroscopy in a murine femoral segmental defect model. Blood flow was measured at several positions proximal and distal to the graft site before implantation and every week post-implantation for a total of 9 weeks (autograft n = 7 and allograft n = 10). Measurements of the ipsilateral leg with the graft were compared with those of the intact contralateral control leg. Both autografts and allografts exhibited an initial increase in blood flow followed by a gradual return to baseline levels. Blood flow elevation lasted up to 2 weeks in autografts, but this duration varied from 2 to 6 weeks in allografts depending on the spatial location of the measurement. Intact contralateral control leg blood flow remained at baseline levels throughout the 9 weeks in the autograft group; however, in the allograft group, blood flow followed a similar trend to the graft leg. Blood flow difference between the graft and contralateral legs (ΔrBF), a parameter defined to estimate graft-specific changes, was elevated at 1–2 weeks for the autograft group, and at 2–4 weeks for the allograft group at the proximal and the central locations. However, distal to the graft, the allograft group exhibited significantly greater ΔrBF than the autograft group at 3 weeks post-surgery (p < 0.05). These spatial and temporal differences in blood flow supports established trends of delayed healing in allografts versus autografts.
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Affiliation(s)
- Songfeng Han
- Institute of Optics, University of Rochester, Rochester, New York, United States of America
| | - Michael D. Hoffman
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
- Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Ashley R. Proctor
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Joseph B. Vella
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
- Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Otolaryngology-Head and Neck Surgery, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Emmanuel A. Mannoh
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Nathaniel E. Barber
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Hyun Jin Kim
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Ki Won Jung
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Danielle S. W. Benoit
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
- Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Chemical Engineering, University of Rochester, Rochester, New York, United States of America
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Regine Choe
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
- Department of Electrical and Computer Engineering, University of Rochester, New York, United States of America
- * E-mail:
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30
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Heinonen I, Kalliokoski KK, Hannukainen JC, Duncker DJ, Nuutila P, Knuuti J. Organ-specific physiological responses to acute physical exercise and long-term training in humans. Physiology (Bethesda) 2015; 29:421-36. [PMID: 25362636 DOI: 10.1152/physiol.00067.2013] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Virtually all tissues in the human body rely on aerobic metabolism for energy production and are therefore critically dependent on continuous supply of oxygen. Oxygen is provided by blood flow, and, in essence, changes in organ perfusion are also closely associated with alterations in tissue metabolism. In response to acute exercise, blood flow is markedly increased in contracting skeletal muscles and myocardium, but perfusion in other organs (brain and bone) is only slightly enhanced or is even reduced (visceral organs). Despite largely unchanged metabolism and perfusion, repeated exposures to altered hemodynamics and hormonal milieu produced by acute exercise, long-term exercise training appears to be capable of inducing effects also in tissues other than muscles that may yield health benefits. However, the physiological adaptations and driving-force mechanisms in organs such as brain, liver, pancreas, gut, bone, and adipose tissue, remain largely obscure in humans. Along these lines, this review integrates current information on physiological responses to acute exercise and to long-term physical training in major metabolically active human organs. Knowledge is mostly provided based on the state-of-the-art, noninvasive human imaging studies, and directions for future novel research are proposed throughout the review.
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Affiliation(s)
- Ilkka Heinonen
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku and Turku University Hospital, Turku, Finland; Department of Cardiology, Division of Experimental Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Kari K Kalliokoski
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
| | - Jarna C Hannukainen
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
| | - Dirk J Duncker
- Department of Cardiology, Division of Experimental Cardiology, Thoraxcenter, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Pirjo Nuutila
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland; Department of Medicine, University of Turku and Turku University Hospital, Turku, Finland; and
| | - Juhani Knuuti
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland
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31
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Binzoni T, Spinelli L. Near-infrared photons: a non-invasive probe for studying bone blood flow regulation in humans. J Physiol Anthropol 2015. [PMID: 26205147 PMCID: PMC4513383 DOI: 10.1186/s40101-015-0066-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The study of bone blood flow regulation in humans has always represented a difficult task for the clinician and the researcher. Classical measurement techniques imply the presence of ionizing radiation or contrast agents, or they are slow or cannot be repeated too often in time. In the present review, we would like to give a perspective on how the optical approach might overcome some of these problems and give unique solutions to the study of bone blood flow regulation. We hope that the present contribution will encourage the scientific community to put a greater attention on this approach.
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Affiliation(s)
- Tiziano Binzoni
- Département de Neurosciences Fondamentales, University of Geneva, Geneva, Switzerland. .,Département de l'Imagerie et des Sciences de l'Information Médicale, University Hospital, Geneva, Switzerland.
| | - Lorenzo Spinelli
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milano, Italy.
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32
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Griffith JF. Functional imaging of the musculoskeletal system. Quant Imaging Med Surg 2015; 5:323-31. [PMID: 26029633 DOI: 10.3978/j.issn.2223-4292.2015.03.07] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 02/28/2015] [Indexed: 12/17/2022]
Abstract
Functional imaging, which provides information of how tissues function rather than structural information, is well established in neuro- and cardiac imaging. Many musculoskeletal structures, such as ligaments, fascia and mineralized bone, have by definition a mainly structural role and clearly don't have the same functional capacity as the brain, heart, liver or kidney. The main functionally responsive musculoskeletal tissues are the bone marrow, muscle and nerve and, as such, magnetic resonance (MR) functional imaging has primarily addressed these areas. Proton or phosphorus spectroscopy, other fat quantification techniques, perfusion imaging, BOLD imaging, diffusion and diffusion tensor imaging (DTI) are the main functional techniques applied. The application of these techniques in the musculoskeletal system has mainly been research orientated where they have already greatly enhanced our understanding of marrow physiology, muscle physiology and neural function. Going forwards, they will have a greater clinical impact helping to bridge the disconnect often seen between structural appearances and clinical symptoms, allowing a greater understanding of disease processes and earlier recognition of disease, improving prognostic prediction and optimizing the monitoring of treatment effect.
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Affiliation(s)
- James F Griffith
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China
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33
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Dyke JP, Synan M, Ezell P, Ballon D, Racine J, Aaron RK. Characterization of bone perfusion by dynamic contrast-enhanced magnetic resonance imaging and positron emission tomography in the Dunkin-Hartley guinea pig model of advanced osteoarthritis. J Orthop Res 2015; 33:366-72. [PMID: 25410523 PMCID: PMC4346481 DOI: 10.1002/jor.22768] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 10/11/2014] [Indexed: 02/04/2023]
Abstract
This study characterizes changes in subchondral bone circulation in OA and examines relationships to bone structure and cartilage degeneration in Dunkin-Hartley guinea pigs. We have used dynamic contrast-enhanced MRI (DCE-MRI) and PET, with pharmacokinetic modeling, to characterize subchondral bone perfusion. Assessments are made of perfusion kinetics and vascular permeability by MRI, and blood volume and flow, and radionuclide incorporation into bone, by PET. These parameters are compared to cartilage lesion severity and bone histomorphometry. Assessments of intraosseous thrombi are made morphologically. Prolonged signal enhancement during the clearance phase of MRI correlated with OA severity and suggested venous stasis. Vascular permeability was not increased indicating that transvascular migration of contrast agent was not responsible for signal enhancement. Intraosseous thrombi were not observed. Decreased perfusion associated with severe OA was confirmed by PET and was associated with reduced radionuclide incorporation and osteoporosis. MRI and PET can be used to characterize kinetic parameters of circulation in OA and correlate them with subchondral bone metabolism of interest to the pathophysiology of OA. The significance of these observations may lie in alterations induced in the expression of cytokines by OA osteoblasts that are related to bone remodeling and cartilage breakdown.
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Affiliation(s)
- Jonathan P. Dyke
- Department of Radiology, Weill Cornell Medical College, New York, NY,Citigroup Biomedical Imaging Center, Weill Cornell Medical College, New York, NY
| | - Michael Synan
- Citigroup Biomedical Imaging Center, Weill Cornell Medical College, New York, NY
| | - Paula Ezell
- Department of Comparative Medicine, Medical University of South Carolina, Charleston, SC
| | - Douglas Ballon
- Department of Radiology, Weill Cornell Medical College, New York, NY,Citigroup Biomedical Imaging Center, Weill Cornell Medical College, New York, NY
| | - Jennifer Racine
- Department of Orthopedics, The Warren Alpert Medical School of Brown University, Providence, RI
| | - Roy K. Aaron
- Department of Orthopedics, The Warren Alpert Medical School of Brown University, Providence, RI
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Usefulness of dynamic contrast-enhanced MRI in the evaluation of the viability of acute scaphoid fracture. Skeletal Radiol 2014; 43:1697-703. [PMID: 25145596 DOI: 10.1007/s00256-014-1981-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 07/17/2014] [Accepted: 07/31/2014] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To evaluate the usefulness of dynamic gadolinium-enhanced magnetic resonance imaging (MRI) for assessing the viability of the proximal pole of the scaphoid in patients with acute scaphoid fractures. METHODS Eighteen consecutive patients with acute scaphoid fracture who underwent dynamic gadolinium-enhanced MRI 7 days or less before surgery were prospectively included between August 2011 and December 2012. All patients underwent MR imaging with unenhanced images, enhanced images, and dynamic enhanced images. A radiologist first classified the MRI results as necrotic or viable based on T1- and T2-weighted images only, followed by a second blinded interpretation, this time including analysis of pre- and post-gadolinium administration images and a third blinded interpretation based on the time-intensity curve of the dynamic enhanced study. The standard of reference was the histologic assessment of a cylindrical specimen of the proximal pole obtained during surgery in all patients. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for unenhanced, enhanced, and dynamic gadolinium-enhanced MRI studies. RESULTS The sensitivity, specificity, PPV, and NPV were 67, 67, 50, and 80 % for unenhanced images, 83, 100, 100, and 92 for enhanced images, and 83, 92, 83, and 92 for dynamic contrast-enhanced images. CONCLUSIONS Our data are consistent with previously reported data supporting contrast-enhanced MRI for assessment of viability, and showing that dynamic imaging with time-intensity curve analysis does not provide additional predictive value over standard delayed enhanced imaging for acute scaphoid fracture.
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Abstract
Environmental temperature can have a surprising impact on extremity growth in homeotherms, but the underlying mechanisms have remained elusive for over a century. Limbs of animals raised at warm ambient temperature are significantly and permanently longer than those of littermates housed at cooler temperature. These remarkably consistent lab results closely resemble the ecogeographical tenet described by Allen's "extremity size rule," that appendage length correlates with temperature and latitude. This phenotypic growth plasticity could have adaptive significance for thermal physiology. Shortened extremities help retain body heat in cold environments by decreasing surface area for potential heat loss. Homeotherms have evolved complex mechanisms to maintain tightly regulated internal temperatures in challenging environments, including "facultative extremity heterothermy" in which limb temperatures can parallel ambient. Environmental modulation of tissue temperature can have direct and immediate consequences on cell proliferation, metabolism, matrix production, and mineralization in cartilage. Temperature can also indirectly influence cartilage growth by modulating circulating levels and delivery routes of essential hormones and paracrine regulators. Using an integrated approach, this article synthesizes classic studies with new data that shed light on the basis and significance of this enigmatic growth phenomenon and its relevance for treating human bone elongation disorders. Discussion centers on the vasculature as a gateway to understanding the complex interconnection between direct (local) and indirect (systemic) mechanisms of temperature-enhanced bone lengthening. Recent advances in imaging modalities that enable the dynamic study of cartilage growth plates in vivo will be key to elucidating fundamental physiological mechanisms of long bone growth regulation.
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Affiliation(s)
- Maria A Serrat
- Department of Anatomy and Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
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Binzoni T, Van De Ville D, Sanguinetti B. Time-domain algorithm for single-photon laser-Doppler flowmetry at large interoptode spacing in human bone. APPLIED OPTICS 2014; 53:7017-7024. [PMID: 25402789 DOI: 10.1364/ao.53.007017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 09/06/2014] [Indexed: 06/04/2023]
Abstract
A new laser-Doppler flowmeter at large interoptode spacing, based on single-photon counting (single-photon laser-Doppler flowmetry [SP-LDF]) and allowing assessment of blood flow deep in bone tissue, is proposed and implemented. To exploit the advantages of the new SP-LDF hardware, a dedicated simple and efficient time-domain algorithm has been developed. The new algorithm is based on the zero-order moment of the power density spectrum of the ad hoc prefiltered photoelectric current. The SP-LDF has been validated by Monte Carlo simulations, as well as by experimental measurements on a bone tissue phantom for optical flowmeters and on human.
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Bouvard B, Abed E, Yéléhé-Okouma M, Bianchi A, Mainard D, Netter P, Jouzeau JY, Lajeunesse D, Reboul P. Hypoxia and vitamin D differently contribute to leptin and dickkopf-related protein 2 production in human osteoarthritic subchondral bone osteoblasts. Arthritis Res Ther 2014; 16:459. [PMID: 25312721 PMCID: PMC4302570 DOI: 10.1186/s13075-014-0459-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 09/18/2014] [Indexed: 12/17/2022] Open
Abstract
Introduction Bone remodelling and increased subchondral densification are important in osteoarthritis (OA). Modifications of bone vascularization parameters, which lead to ischemic episodes associated with hypoxic conditions, have been suspected in OA. Among several factors potentially involved, leptin and dickkopf-related protein 2 (DKK2) are good candidates because they are upregulated in OA osteoblasts (Obs). Therefore, in the present study, we investigated the hypothesis that hypoxia may drive the expression of leptin and DKK2 in OA Obs. Methods Obs from the sclerotic portion of OA tibial plateaus were cultured under either 20% or 2% oxygen tension in the presence or not of 50 nM 1,25-dihydroxyvitamin D3 (VitD3). The expression of leptin, osteocalcin, DKK2, hypoxia-inducible factor 1α (Hif-1α) and Hif-2α was measured by real-time polymerase chain reaction and leptin production was measured by enzyme-linked immunosorbent assay (ELISA). The expression of Hif-1α, Hif-2α, leptin and DKK2 was reduced using silencing RNAs (siRNAs). The signalling pathway of hypoxia-induced leptin was investigated by Western blot analysis and with mitogen-activated protein kinase (MAPK) inhibitors. Results The expression of leptin and DKK2 in Obs was stimulated 7-fold and 1.8-fold, respectively (P <0.05) under hypoxia. Interestingly, whereas VitD3 stimulated leptin and DKK2 expression 2- and 4.2-fold, respectively, under normoxia, it stimulated their expression by 28- and 6.2-fold, respectively, under hypoxia (P <0.05). The hypoxia-induced leptin production was confirmed by ELISA, particularly in the presence of VitD3 (P <0.02). Compared to Obs incubated in the presence of scramble siRNAs, siHif-2α inhibited VitD3-stimulated leptin mRNA and protein levels by 70% (P =0.004) and 60% (P <0.02), respectively, whereas it failed to significantly alter the expression of DKK2. siHif-1α has no effect on these genes. Immunoblot analysis showed that VitD3 greatly stabilized Hif-2α under hypoxic conditions. The increase in leptin expression under hypoxia was also regulated, by p38 MAPK (P <0.03) and phosphoinositide 3-kinase (P <0.05). We found that the expression of leptin and DKK2 were not related to each other under hypoxia. Conclusions Hypoxic conditions via Hif-2 regulation trigger Obs to produce leptin, particularly under VitD3 stimulation, whereas DKK2 is regulated mainly by VitD3 rather than hypoxia.
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Budzik JF, Lefebvre G, Forzy G, El Rafei M, Chechin D, Cotten A. Study of proximal femoral bone perfusion with 3D T1 dynamic contrast-enhanced MRI: a feasibility study. Eur Radiol 2014; 24:3217-23. [PMID: 25120203 DOI: 10.1007/s00330-014-3340-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 05/28/2014] [Accepted: 07/10/2014] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The objective of this study was to compare measurements of semi-quantitative and pharmacokinetic parameters in areas of red (RBM) and yellow bone marrow (YBM) of the hip, using an in-house high-resolution DCE T1 sequence, and to assess intra- and inter-observer reproducibility of these measurements. METHODS The right hips of 21 adult patients under 50 years of age were studied. Spatial resolution was 1.8 × 1.8 × 1.8 mm(3), and temporal resolution was 13.5 seconds. Two musculoskeletal radiologists independently processed DCE images and measured semi-quantitative and pharmacokinetic parameters in areas of YBM and RBM. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated. Intra- and inter-observer reproducibility was assessed. RESULTS Area under the curve (AUC) and initial slope (IS) were significantly greater for RBM than for YBM (p < 0.05). K(trans) and kep were also significantly greater for RBM (p < 0.05). There was no significant difference in time to peak between the regions (p < 0.05). SNR, CNR, and intra- and inter-observer reproducibility were all good. CONCLUSIONS DCE study of the whole hip is feasible with high spatial resolution using a 3D T1 sequence. Measures were possible even in low vascularized areas of the femoral head. K(trans), kep, AUC, and IS values were significantly different between red and yellow marrow, whereas TTP values were not. KEY POINTS High-spatial-resolution dynamic contrast-enhanced MRI of hip structures is feasible. Intra- and inter-observer reproducibility is good. Red and yellow bone marrow have different perfusion patterns.
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Affiliation(s)
- Jean-François Budzik
- Service d'Imagerie Médicale, Groupe Hospitalier de l'Institut Catholique de Lille / Faculté Libre de Médecine, 59000, Lille, France,
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Fan H, Zeng X, Wang X, Zhu R, Pei G. Efficacy of prevascularization for segmental bone defect repair using β-tricalcium phosphate scaffold in rhesus monkey. Biomaterials 2014; 35:7407-15. [PMID: 24909103 DOI: 10.1016/j.biomaterials.2014.05.035] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 05/14/2014] [Indexed: 10/25/2022]
Abstract
Although small animal model (rabbit) showed successful bone defect repair using prevascularized tissue-engineered bone grafts (TEBG), large animal (rhesus monkey) studies are still needed to extrapolate the findings from animal data to humans. In current study, we investigated the efficacy of prevascularized TEBG for segmental bone defect repair in rhesus monkey. The segmental diaphyseal defects were created in both tibias. In group A, the defect was filled with prevascularized MSCs/scaffold prepared by inserting saphenous vascular bundle into the side groove and a fascia flap coverage; In group B, the defect was filled with MSCs/scaffold with a fascia flap coverage; In group C, the defect was filled with MSCs/scaffold; In group D, the defect was filled with only scaffold. The angiogenesis and new bone formation were compared among groups at 4, 8, and 12 weeks postoperatively. The results showed the prevascularized TEBG in group A could augment new bone formation and capillary vessel in-growth. It had significantly higher values of vascularization and radiographic grading score compared with other groups. In conclusion, the in vivo experiment data of prevascularized TEBG was further enriched from small to large animal model. It implies that prevascularized TEBG has great potentials in clinical applications.
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Affiliation(s)
- Hongbin Fan
- Department of Orthopedic Surgery, Xijing Hospital, The Fourth Military Medical University, 17 West Changle Road, Xi'an, China
| | - Xianli Zeng
- Department of Orthopaedics & Traumatology, Nanfang Hospital, Nanfang Medical University, Guangzhou, China
| | - Xueming Wang
- Department of Orthopaedics & Traumatology, Nanfang Hospital, Nanfang Medical University, Guangzhou, China
| | - Rui Zhu
- Collage of Science, Engineering University of Air Force, Xi'an, China
| | - Guoxian Pei
- Department of Orthopedic Surgery, Xijing Hospital, The Fourth Military Medical University, 17 West Changle Road, Xi'an, China.
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Guda T, Labella C, Chan R, Hale R. Quality of bone healing: Perspectives and assessment techniques. Wound Repair Regen 2014; 22 Suppl 1:39-49. [DOI: 10.1111/wrr.12167] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 01/28/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Teja Guda
- Dental Trauma Research Detachment; US Army Institute of Surgical Research; Fort Sam Houston
- Wake Forest Institute for Regenerative Medicine; Winston-Salem North Carolina
- Biomedical Engineering; University of Texas at San Antonio; San Antonio Texas
| | - Carl Labella
- Dental Trauma Research Detachment; US Army Institute of Surgical Research; Fort Sam Houston
| | - Rodney Chan
- Dental Trauma Research Detachment; US Army Institute of Surgical Research; Fort Sam Houston
| | - Robert Hale
- Dental Trauma Research Detachment; US Army Institute of Surgical Research; Fort Sam Houston
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Dyke JP, Lazaro LE, Hettrich CM, Hentel KD, Helfet DL, Lorich DG. Regional analysis of femoral head perfusion following displaced fractures of the femoral neck. J Magn Reson Imaging 2013; 41:550-4. [PMID: 24338938 DOI: 10.1002/jmri.24524] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 11/09/2013] [Indexed: 12/13/2022] Open
Abstract
PURPOSE To assess regional variations in the arterial and venous blood supply to the femoral head following displaced fracture of the femoral neck using dynamic contrast enhanced (DCE)-MRI quadrant analysis. MATERIALS AND METHODS A total of 27 subjects with displaced femoral neck fractures were enrolled in the study. Quadrant specific DCE-MRI perfusion analysis was performed on a 1.5 Tesla MRI scanner. Simultaneous imaging of control and displaced fractured hips was done for comparison. RESULTS Quadrant specific decreases were found in the arterial (A (0.52 versus 0.27; P = 5.7E-13), Akep (1.0/min(-1) versus 0.41/min(-1) ; P = 1.3E-9) and venous (kel (0.05/min(-1) versus -0.02/min(-1) ; P = 5.1E-5) supply to the femoral head between control and injured sides using a two-factor analysis of variance test. The fractional perfusion (initial area under the curve) in the supero/inferolateral quadrants was 49% min/54% min, in the supero/inferomedial quadrants was 43% min/46% min and for the total femoral head was 39% min on the fracture versus control sides. CONCLUSION Quadrant specific decreases in arterial and venous perfusion on the fracture side were observed when compared with control.
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Affiliation(s)
- Jonathan P Dyke
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
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Cuenod C, Balvay D. Perfusion and vascular permeability: Basic concepts and measurement in DCE-CT and DCE-MRI. Diagn Interv Imaging 2013; 94:1187-204. [DOI: 10.1016/j.diii.2013.10.010] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Dynamic contrast-enhanced magnetic resonance imaging can assess vascularity within fracture non-unions and predicts good outcome. Eur Radiol 2013; 24:449-59. [DOI: 10.1007/s00330-013-3043-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 09/23/2013] [Accepted: 10/01/2013] [Indexed: 01/31/2023]
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Measurement of blood perfusion in spinal metastases with dynamic contrast-enhanced magnetic resonance imaging: evaluation of tumor response to radiation therapy. Spine (Phila Pa 1976) 2013; 38:E1418-24. [PMID: 23873238 PMCID: PMC5757658 DOI: 10.1097/brs.0b013e3182a40838] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN This was a retrospective study focusing on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess treatment response in patients with spinal metastases. OBJECTIVE To demonstrate DCE-MRI changes before and after radiation treatment and correlating with other imaging and clinical findings. SUMMARY OF BACKGROUND DATA Currently, conventional imaging is limited in evaluating early treatment success or failure, which impacts patient care. METHODS Consecutive patients with known spinal metastases underwent DCE-MRI before and after radiotherapy. Perfusion data on 19 lesions were analyzed. Radiotherapy was classified as success (n = 17) or failure (n = 2) on the basis of evidence of tumor contraction (n = 4), negative positron emission tomography (n = 2), or stability for more than 11 months (n = 11). Perfusion parameters blood plasma volume (Vp), time-dependent leakage (Ktrans), area under the curve, and peak enhancement were derived from the signal intensity-time curves and changes in parameter values from pre- to post-treatment were calculated. Curve morphologies were also qualitatively assessed in 13 pre- and 13 post-treatment scans. RESULTS Vp was the strongest predictor of treatment response (false-positive rate = 9.38 × 10 and false-negative rate = 0.055). All successfully treated lesions showed decreases in Vp, and the 2 treatment failures showed drastic increases in Vp. Changes in area under the curve and peak enhancement demonstrated similar relationships to the observed treatment response, whereas changes in Ktrans showed no significant relationship. Signal intensity curve morphologies also demonstrated specificity for active disease (11 of 13) and treated disease (8 of 13). CONCLUSION Changes in perfusion, particularly Vp, reflect tumor responses to radiotherapy in spinal bone metastases. These changes were able to predict positive outcomes earlier than 6 months after treatment in 16 of 17 tumors. The ability of DCE-MRI to detect early treatment response has the potential to improve patient care and outcome.
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Borges N, Serakides R, Santos R, Diniz S, Cardoso V, Ucros N, Torres R, Cardoso S, Rezende C. Scintigraphy in postoperative follow-up of osteosynthesis of the femur with a bridge plate associated with an intramedullary pin in rabbits. ARQ BRAS MED VET ZOO 2013. [DOI: 10.1590/s0102-09352013000400018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The objective of this work was to monitor the consolidation of the femur after osteosynthesis with a bridge plate associated with the intramedullary pin using scintigraphy. We used seven New Zealand breed male rabbits, at 4 months of age, with a mean weight of 3.5 kg. We performed a three-phase bone scintigraphy with technetium-labeled methylene diphosphonate (99mTc-MDP) before and after surgery, and 20, 50 and 90 days postoperatively. The activity index (AI) was calculated by dividing the average number of uptake counts in the region of the osteotomy by the average number of counts in the corresponding region in the contralateral limb. Radiography was performed before surgery, after surgery, and 15, 30, 45, 60 and 90 days postoperatively. We found a direct relationship between the activity index and progress of bone scintigraphy in the evaluation sequence over the period of observation. Scintigraphy allows monitoring of bone metabolism and measurement of vascularization and/or bone or tissue perfusion. The images obtained in the blood pool and static phases are the most appropriate for assessing bone metabolism in the context of this study. The bridge plate associated with the intramedullary pin promotes osteosynthesis with sufficient stability to allow bone consolidation.
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Affiliation(s)
| | | | - R.G. Santos
- Centro de Desenvolvimento da Tecnologia Nuclear
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Heinonen I, Kemppainen J, Kaskinoro K, Langberg H, Knuuti J, Boushel R, Kjaer M, Kalliokoski KK. Bone blood flow and metabolism in humans: effect of muscular exercise and other physiological perturbations. J Bone Miner Res 2013; 28:1068-74. [PMID: 23280932 DOI: 10.1002/jbmr.1833] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 10/24/2012] [Accepted: 11/14/2012] [Indexed: 11/06/2022]
Abstract
Human bone blood flow and metabolism during physical exercise remains poorly characterized. In the present study we measured femoral bone blood flow and glucose uptake in young healthy subjects by positron emission tomography in three separate protocols. In 6 women, blood flow was measured in femoral bone at rest and during one-leg intermittent isometric exercise with increasing exercise intensities. In 9 men, blood flow in the femur was determined at rest and during dynamic one-leg exercise and two other physiological perturbations: moderate systemic hypoxia (14 O2 ) at rest and during exercise, and during intrafemoral infusion of high-dose adenosine. Bone glucose uptake was measured at rest and during dynamic one-leg exercise in 5 men. The results indicate that isometric exercise increased femoral bone blood flow from rest (1.8 ± 0.6 mL/100 g/min) to low intensity exercise (4.1 ± 1.5 mL/100 g/min, p = 0.01), but blood flow did not increase further with increasing intensity. Resting femoral bone blood flow in men was similar to that of women and dynamic one-leg exercise increased it to 4.2 ± 1.2 mL/100 g/min, p < 0.001. Breathing of hypoxic air did not change femoral bone blood flow at rest or during exercise, but intra-arterial infusion of adenosine during resting conditions increased bone blood flow to 5.7 ± 2.4 mL/100 g/min, to the level of moderate-intensity dynamic exercise. Dynamic one-leg exercise increased femoral bone glucose uptake 4.7-fold compared to resting contralateral leg. In conclusion, resting femoral bone blood flow increases by physical exercise, but appears to level off with increasing exercise intensities. Moreover, although moderate systemic hypoxia does not change bone blood flow at rest or during exercise, intra-arterially administered adenosine during resting conditions is capable of markedly enhancing bone blood flow in humans. Finally, bone glucose uptake also increases substantially in response to exercise.
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Affiliation(s)
- Ilkka Heinonen
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
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Binzoni T, Tchernin D, Hyacinthe JN, Van De Ville D, Richiardi J. Pulsatile blood flow in human bone assessed by laser-Doppler flowmetry and the interpretation of photoplethysmographic signals. Physiol Meas 2013; 34:N25-40. [PMID: 23443008 DOI: 10.1088/0967-3334/34/3/n25] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Human bone blood flow, mean blood speed and the number of moving red blood cells were assessed (in arbitrary units), as a function of time, during one cardiac cycle. The measurements were obtained non-invasively on five volunteers by laser-Doppler flowmetry at large interoptode spacing. The investigated bones included: patella, clavicle, tibial diaphysis and tibial malleolus. As hypothesized, we found that in all bones the number of moving cells remains constant during cardiac cycles. Therefore, we concluded that the pulsatile nature of blood flow must be completely determined by the mean blood speed and not by changes in blood volume (vessels dilation). Based on these results, it is finally demonstrated using a mathematical model (derived from the radiative transport theory) that photoplethysmographic (PPG) pulsations observed by others in the literature, cannot be generated by oscillations in blood oxygen saturation, which is physiologically linked to blood speed. In fact, possible oxygen saturation changes during pulsations decrease the amplitude of PPG pulsations due to specific features of the PPG light source. It is shown that a variation in blood oxygen saturation of 3% may induce a negative change of ∼1% in the PPG signal. It is concluded that PPG pulsations are determined by periodic 'positive' changes of the reduced scattering coefficient of the tissue and/or the absorption coefficient at constant blood volume. No explicit experimental PPG measurements have been performed. As a by-product of this study, an estimation of the arterial pulse wave velocity obtained from the analysis of the blood flow pulsations give a value of 7.8 m s(-1) (95% confidence interval of the sample mean distribution: [6.7, 9.5] m s(-1)), which is perfectly compatible with data in the literature. We hope that this note will contribute to a better understanding of PPG signals and to further develop the domain of the vascular physiology of human bone.
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Affiliation(s)
- Tiziano Binzoni
- Département de Neurosciences Fondamentales, University of Geneva, Geneva, Switzerland.
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Dietrich O. Techniques for Diffusion and Perfusion Assessment in Bone-Marrow MRI. MAGNETIC RESONANCE IMAGING OF THE BONE MARROW 2013. [DOI: 10.1007/174_2012_549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Quantification of skeletal blood flow and fluoride metabolism in rats using PET in a pre-clinical stress fracture model. Mol Imaging Biol 2012; 14:348-54. [PMID: 21785919 DOI: 10.1007/s11307-011-0505-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE Blood flow is an important factor in bone production and repair, but its role in osteogenesis induced by mechanical loading is unknown. Here, we present techniques for evaluating blood flow and fluoride metabolism in a pre-clinical stress fracture model of osteogenesis in rats. PROCEDURES Bone formation was induced by forelimb compression in adult rats. (15)O water and (18)F fluoride PET imaging were used to evaluate blood flow and fluoride kinetics 7 days after loading. (15)O water was modeled using a one-compartment, two-parameter model, while a two-compartment, three-parameter model was used to model (18)F fluoride. Input functions were created from the heart, and a stochastic search algorithm was implemented to provide initial parameter values in conjunction with a Levenberg-Marquardt optimization algorithm. RESULTS Loaded limbs are shown to have a 26% increase in blood flow rate, 113% increase in fluoride flow rate, 133% increase in fluoride flux, and 13% increase in fluoride incorporation into bone as compared to non-loaded limbs (p < 0.05 for all results). CONCLUSIONS The results shown here are consistent with previous studies, confirming this technique is suitable for evaluating the vascular response and mineral kinetics of osteogenic mechanical loading.
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Würbach L, Heidrich A, Opfermann T, Gebhardt P, Saluz HP. Insights into Bone Metabolism of Avian Embryos In Ovo Via 3D and 4D 18F-fluoride Positron Emission Tomography. Mol Imaging Biol 2012; 14:688-98. [DOI: 10.1007/s11307-012-0550-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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