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Martel D, Monga A, Chang G. Osteoporosis Imaging. Radiol Clin North Am 2022; 60:537-545. [DOI: 10.1016/j.rcl.2022.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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2
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Götestrand S, Björkman A, Björkman-Burtscher IM, Kristiansson I, Aksyuk E, Szaro P, Markenroth Bloch K, Geijer M. Visualization of wrist anatomy-a comparison between 7T and 3T MRI. Eur Radiol 2021; 32:1362-1370. [PMID: 34378077 PMCID: PMC8795032 DOI: 10.1007/s00330-021-08165-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/16/2021] [Accepted: 06/24/2021] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Injuries to the wrist are, due to its small size and complex anatomical structures, difficult to assess by MR, and surgical interventions such as diagnostic arthroscopy are often necessary. Therefore, improved visualization using non-invasive methods could be of clinical value. As a first step of improvement, the purpose of this study was to evaluate visualization of anatomical structures at 7T compared with 3T MR. METHODS Eighteen healthy volunteers (three males and three females from each age decade between 20 and 49 years) were examined with 7T and 3T MR. Four musculoskeletal radiologists graded 2D and 3D images on a five-level grading scale for visibility of ligaments, cartilage, nerves, trabecular bone, and tendons, as well as overall image quality (i.e., edge sharpness, perceived tissue contrast, and presence of artefacts). Statistical analysis was done using a visual grading characteristics (VGC) analysis. RESULTS Visibility of cartilage, trabecular bone, tendons, nerves, and ligaments was graded significantly higher at 7T with an area under the curve (AUCVGC) of 0.62-0.88 (95% confidence interval [CI] 0.50-0.97, p = < 0.0001-0.03) using either 2D or 3D imaging. Imaging with 3T was not graded as superior to 7T for any structure. Image quality was also significantly superior at 7T, except for artefacts, where no significant differences were found. CONCLUSIONS Tendons, trabecular bone, nerves, and ligaments were all significantly better visualized at 7T compared to 3T. KEY POINTS • MRI of the wrist at 7T with a commercially available wrist coil is feasible at similar acquisition times as for 3T MRI. • The current study showed 7T to be superior to 3T in the visualization of anatomical structures of the wrist, including ligaments, tendons, nerves, and trabecular bone. • Image quality was significantly superior at 7T, except for artefacts, where no significant differences were found.
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Affiliation(s)
- Simon Götestrand
- Department of Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden. .,Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden.
| | - Anders Björkman
- Department of Hand Surgery, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - Isabella M Björkman-Burtscher
- Department of Radiology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Radiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - Ingvar Kristiansson
- Department of Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden
| | - Elenya Aksyuk
- Department of Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden.,Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden
| | - Pawel Szaro
- Department of Radiology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | | | - Mats Geijer
- Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden.,Department of Radiology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Radiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
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Guha I, Nadeem SA, You C, Zhang X, Levy SM, Wang G, Torner JC, Saha PK. Deep Learning Based High-Resolution Reconstruction of Trabecular Bone Microstructures from Low-Resolution CT Scans using GAN-CIRCLE. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2020; 11317:113170U. [PMID: 32201450 PMCID: PMC7085412 DOI: 10.1117/12.2549318] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Osteoporosis is a common age-related disease characterized by reduced bone density and increased fracture-risk. Microstructural quality of trabecular bone (Tb), commonly found at axial skeletal sites and at the end of long bones, is an important determinant of bone-strength and fracture-risk. High-resolution emerging CT scanners enable in vivo measurement of Tb microstructures at peripheral sites. However, resolution-dependence of microstructural measures and wide resolution-discrepancies among various CT scanners together with rapid upgrades in technology warrant data harmonization in CT-based cross-sectional and longitudinal bone studies. This paper presents a deep learning-based method for high-resolution reconstruction of Tb microstructures from low-resolution CT scans using GAN-CIRCLE. A network was developed and evaluated using post-registered ankle CT scans of nineteen volunteers on both low- and high-resolution CT scanners. 9,000 matching pairs of low- and high-resolution patches of size 64×64 were randomly harvested from ten volunteers for training and validation. Another 5,000 matching pairs of patches from nine other volunteers were used for evaluation. Quantitative comparison shows that predicted high-resolution scans have significantly improved structural similarity index (p < 0.01) with true high-resolution scans as compared to the same metric for low-resolution data. Different Tb microstructural measures such as thickness, spacing, and network area density are also computed from low- and predicted high-resolution images, and compared with the values derived from true high-resolution scans. Thickness and network area measures from predicted images showed higher agreement with true high-resolution CT (CCC = [0.95, 0.91]) derived values than the same measures from low-resolution images (CCC = [0.72, 0.88]).
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Affiliation(s)
- Indranil Guha
- Department of Electrical and Computer Engineering, College of Engineering, University of Iowa, Iowa City, IA 52242
| | - Syed Ahmed Nadeem
- Department of Electrical and Computer Engineering, College of Engineering, University of Iowa, Iowa City, IA 52242
| | - Chenyu You
- Department of Computer Science, Yale University, New Haven, CT 05620
| | - Xiaoliu Zhang
- Department of Electrical and Computer Engineering, College of Engineering, University of Iowa, Iowa City, IA 52242
| | - Steven M Levy
- Department of Preventive and Community Dentistry, College of Dentistry, University of Iowa, Iowa City, IA 52242
| | - Ge Wang
- Biomedical Imaging Center, BME/CBIS, Rensselaer Polytechnic Institute, Troy, New York, NY 12180
| | - James C Torner
- Department of Epidemiology, University of Iowa, Iowa City, IA 52242
| | - Punam K Saha
- Department of Electrical and Computer Engineering, College of Engineering, University of Iowa, Iowa City, IA 52242
- Department of Radiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
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Zhang X, Letuchy EM, Levy SM, Torner JC, Saha PK. CT-Based Characterization of Transverse and Longitudinal Trabeculae and Its Applications. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2020; 11317:113171F. [PMID: 32201451 PMCID: PMC7085413 DOI: 10.1117/12.2549881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Osteoporosis is a common age-related disease characterized by reduced bone mineral density (BMD), micro-structural deterioration, and enhanced fracture-risk. Although, BMD is clinically used to define osteoporosis, there are compelling evidences that bone micro-structural properties are strong determinants of bone strength and fracture-risk. Reliable measures of effective trabecular bone (Tb) micro-structural features are of paramount clinical significance. Tb consists of transverse and longitudinal micro-structures, and there is a hypothesis that transverse trabeculae improve bone strength by arresting buckling of longitudinal trabeculae. In this paper, we present an emerging clinical CT-based new method for characterizing transverse and longitudinal trabeculae, validate the method, and examine its application in human studies. Specifically, we examine repeat CT scan reproducibility, and evaluate the relationships of these measures with gender and body size using human CT data from the Iowa Bone Development Study (IBDS) (n = 99; 49 female). Based on a cadaveric ankle study (n = 12), both transverse and longitudinal Tb measures are found reproducible (ICC > 0.94). It was observed in the IBDS human data that males have significantly higher trabecular bone measures than females for both inner (p < 0.05) and outer (p < 0.01) regions of interest (ROIs). For weight, Spearman correlations ranged 0.43-0.48 for inner ROI measures and 0.50-0.52 for outer ROI measures for females versus 0.30-0.34 and 0.23-0.25 for males. Correlation with height was lower (0.36-0.39), but still mostly significant for females. No association of trabecular measures with height was found for males.
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Affiliation(s)
- Xiaoliu Zhang
- Department of Electrical and Computer Engineering, University of Iowa, USA
| | | | - Steven M Levy
- Department of Preventive and Community Dentistry, University of Iowa, USA
| | | | - Punam K Saha
- Department of Electrical and Computer Engineering, University of Iowa, USA
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5
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Maciel JG, de Araújo IM, Trazzi LC, de Azevedo-Marques PM, Salmon CEG, de Paula FJA, Nogueira-Barbosa MH. Association of bone mineral density with bone texture attributes extracted using routine magnetic resonance imaging. Clinics (Sao Paulo) 2020; 75:e1766. [PMID: 32876107 PMCID: PMC7442400 DOI: 10.6061/clinics/2020/e1766] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 05/26/2020] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Dual-energy X-ray absorptiometry (DXA)-derived bone mineral density (BMD) often fails to predict fragility fractures. Quantitative textural analysis using magnetic resonance imaging (MRI) may potentially yield useful radiomic features to predict fractures. We aimed to investigate the correlation between BMD and texture attributes (TAs) extracted from MRI scans and the interobserver reproducibility of the analysis. METHODS Forty-nine volunteers underwent lumbar spine 1.5-T MRI and DXA. Three-dimensional (3-D) gray-level co-occurrence matrices were measured from routine sagittal T2 fast spin-echo images using the IBEX software. Twenty-two TAs were extracted from 3-D segmented L3 vertebrae. The estimated concordance coefficient was calculated using linear regression analysis. A Pearson correlation coefficient analysis was performed to evaluate the correlation between BMD and the TAs. Interobserver reproducibility was assessed with the concordance coefficient described by Lin. RESULTS The results revealed a fair-to-moderate significant correlation between BMD and 13 TAs (r=-0.20 to 0.39; p<0.05). Eight TAs (autocorrelation, energy, homogeneity 1, homogeneity 1.1, maximum probability, sum average, sum variance, and inverse difference normalized) negatively correlated with BMD (r=-0.20 to -0.38; p<0.05), whereas five TAs (dissimilarity, difference entropy, entropy, sum entropy, and information measure corr 1) positively correlated with BMD (r=0.29-0.39; p<0.05). The interobserver agreement was almost perfect for all significant TAs (95% confidence interval, 0.92-1.00; p<0.05). CONCLUSION Specific TAs could be reliably extracted from routine MRI and correlated with BMD. Our results encourage future evaluation of the potential usefulness of quantitative texture measurements from MRI scans for predicting fragility fractures.
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Affiliation(s)
- Jamilly Gomes Maciel
- Departamento de Imagens Medicas, Hematologia e Oncologia Clinica, Faculdade de Medicina de Ribeirao Preto (FMRP), Universidade de Sao Paulo, Ribeirao Preto, SP, BR
- *Corresponding author. E-mails: /
| | - Iana Mizumukai de Araújo
- Medicina Interna, Faculdade de Medicina de Ribeirao Preto (FMRP), Universidade de Sao Paulo, Ribeirao Preto, SP, BR
| | - Lucio C. Trazzi
- Departamento de Imagens Medicas, Hematologia e Oncologia Clinica, Faculdade de Medicina de Ribeirao Preto (FMRP), Universidade de Sao Paulo, Ribeirao Preto, SP, BR
| | - Paulo Mazzoncini de Azevedo-Marques
- Departamento de Imagens Medicas, Hematologia e Oncologia Clinica, Faculdade de Medicina de Ribeirao Preto (FMRP), Universidade de Sao Paulo, Ribeirao Preto, SP, BR
| | - Carlos Ernesto Garrido Salmon
- Departamento de Fisica, Faculdade de Filosofia, Ciencias e Letras (FFCL), Universidade de São Paulo, Ribeirao Preto, SP, BR
| | | | - Marcello Henrique Nogueira-Barbosa
- Departamento de Imagens Medicas, Hematologia e Oncologia Clinica, Faculdade de Medicina de Ribeirao Preto (FMRP), Universidade de Sao Paulo, Ribeirao Preto, SP, BR
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Alizai H, Chang G, Regatte RR. MR Imaging of the Musculoskeletal System Using Ultrahigh Field (7T) MR Imaging. PET Clin 2019; 13:551-565. [PMID: 30219187 DOI: 10.1016/j.cpet.2018.05.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
MR imaging is an indispensable instrument for the diagnosis of musculoskeletal diseases. In vivo MR imaging at 7T offers many advantages, including increased signal-to-noise ratio, higher spatial resolution, improved spectral resolution for spectroscopy, improved sensitivity for X-nucleus imaging, and decreased image acquisition times. There are also however technical challenges of imaging at a higher field strength compared with 1.5 and 3T MR imaging systems. We discuss the many potential opportunities as well as the challenges presented by 7T MR imaging systems and highlight recent developments in in vivo research imaging of musculoskeletal applications in general and cartilage, skeletal muscle, and bone in particular.
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Affiliation(s)
- Hamza Alizai
- Department of Radiology, New York University Langone Medical Center, 660 First Avenue, New York, NY 10016, USA.
| | - Gregory Chang
- Department of Radiology, New York University Langone Medical Center, 660 First Avenue, New York, NY 10016, USA
| | - Ravinder R Regatte
- Department of Radiology, New York University Langone Medical Center, 660 First Avenue, New York, NY 10016, USA
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7
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Lee DK, Song YK, Park BW, Cho HP, Yeom JS, Cho G, Cho H. The robustness of T 2 value as a trabecular structural index at multiple spatial resolutions of 7 Tesla MRI. Magn Reson Med 2018; 80:1949-1961. [PMID: 29656389 DOI: 10.1002/mrm.27202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/09/2018] [Accepted: 03/11/2018] [Indexed: 12/13/2022]
Abstract
PURPOSE To evaluate the robustness of MR transverse relaxation times of trabecular bone from spin-echo and gradient-echo acquisitions at multiple spatial resolutions of 7 T. METHODS The effects of MRI resolutions to T2 and T2* of trabecular bone were numerically evaluated by Monte Carlo simulations. T2 , T2*, and trabecular structural indices from multislice multi-echo and UTE acquisitions were measured in defatted human distal femoral condyles on a 7 T scanner. Reference structural indices were extracted from high-resolution microcomputed tomography images. For bovine knee trabecular samples with intact bone marrow, T2 and T2* were measured by degrading spatial resolutions on a 7 T system. RESULTS In the defatted trabecular experiment, both T2 and T2* values showed strong ( |r| > 0.80) correlations with trabecular spacing and number, at a high spatial resolution of 125 µm3 . The correlations for MR image-segmentation-derived structural indices were significantly degraded ( |r| < 0.50) at spatial resolutions of 250 and 500 µm3 . The correlations for T2* rapidly dropped ( |r| < 0.50) at a spatial resolution of 500 µm3 , whereas those for T2 remained consistently high ( |r| > 0.85). In the bovine trabecular experiments with intact marrow, low-resolution (approximately 1 mm3 , 2 minutes) T2 values did not shorten ( |r| > 0.95 with respect to approximately 0.4 mm3 , 11 minutes) and maintained consistent correlations ( |r| > 0.70) with respect to trabecular spacing (turbo spin echo, 22.5 minutes). CONCLUSION T2 measurements of trabeculae at 7 T are robust with degrading spatial resolution and may be preferable in assessing trabecular spacing index with reduced scan time, when high-resolution 3D micro-MRI is difficult to obtain.
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Affiliation(s)
- D K Lee
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Y K Song
- Korea Basic Science Institute, Ochang, South Korea
| | - B W Park
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - H P Cho
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - J S Yeom
- Department of Orthopedic Surgery, Seoul National University, Seoul, South Korea
| | - G Cho
- Korea Basic Science Institute, Ochang, South Korea
| | - H Cho
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea
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Guerri S, Mercatelli D, Aparisi Gómez MP, Napoli A, Battista G, Guglielmi G, Bazzocchi A. Quantitative imaging techniques for the assessment of osteoporosis and sarcopenia. Quant Imaging Med Surg 2018. [PMID: 29541624 DOI: 10.21037/qims.2018.01.05] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Bone and muscle are two deeply interconnected organs and a strong relationship between them exists in their development and maintenance. The peak of both bone and muscle mass is achieved in early adulthood, followed by a progressive decline after the age of 40. The increase in life expectancy in developed countries resulted in an increase of degenerative diseases affecting the musculoskeletal system. Osteoporosis and sarcopenia represent a major cause of morbidity and mortality in the elderly population and are associated with a significant increase in healthcare costs. Several imaging techniques are currently available for the non-invasive investigation of bone and muscle mass and quality. Conventional radiology, dual energy X-ray absorptiometry (DXA), computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound often play a complementary role in the study of osteoporosis and sarcopenia, depicting different aspects of the same pathology. This paper presents the different imaging modalities currently used for the investigation of bone and muscle mass and quality in osteoporosis and sarcopenia with special emphasis on the clinical applications and limitations of each technique and with the intent to provide interesting insights into recent advances in the field of conventional imaging, novel high-resolution techniques and fracture risk.
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Affiliation(s)
- Sara Guerri
- The Unit of Diagnostic and Interventional Radiology, The "Rizzoli" Orthopaedic Institute, Bologna, Italy.,Department of Experimental, Diagnostic and Specialty Medicine, Division of Radiology, S.Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy
| | - Daniele Mercatelli
- The Unit of Diagnostic and Interventional Radiology, The "Rizzoli" Orthopaedic Institute, Bologna, Italy
| | - Maria Pilar Aparisi Gómez
- Department of Radiology, Auckland City Hospital, Grafton, Auckland, New Zealand.,Department of Radiology, Hospital Nueve de Octubre, Valencia, Spain
| | - Alessandro Napoli
- Radiology Section, Department of Radiological, Oncological and Anatomopathological Sciences, "Sapienza" University of Rome, Rome, Italy
| | - Giuseppe Battista
- Department of Experimental, Diagnostic and Specialty Medicine, Division of Radiology, S.Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy
| | - Giuseppe Guglielmi
- Department of Radiology, University of Foggia, Foggia, Italy.,Department of Radiology, Scientific Institute "Casa Sollievo della Sofferenza" Hospital, San Giovanni Rotondo, Foggia, Italy
| | - Alberto Bazzocchi
- The Unit of Diagnostic and Interventional Radiology, The "Rizzoli" Orthopaedic Institute, Bologna, Italy
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Griffin LM, Honig S, Chen C, Saha PK, Regatte R, Chang G. 7T MRI of distal radius trabecular bone microarchitecture: How trabecular bone quality varies depending on distance from end-of-bone. J Magn Reson Imaging 2016; 45:872-878. [PMID: 27439146 DOI: 10.1002/jmri.25398] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Accepted: 07/07/2016] [Indexed: 01/18/2023] Open
Abstract
PURPOSE To use 7T magnetic resonance imaging (MRI) to determine how trabecular bone microarchitecture varies at the epiphysis, metaphysis, and diaphysis of the distal radius. MATERIALS AND METHODS The distal radius of 24 females (mean age = 56 years, range = 24-78 years) was scanned on a 7T MRI using a 3D fast low-angle shot sequence (0.169 × 0.169 × 1 mm). Digital topological analysis was applied at the epiphysis, metaphysis, and diaphysis to compute: total trabecular bone volume; trabecular thickness, number, connectivity, and erosion index (a measure of network resorption). Differences and correlations were assessed using standard statistical methods. RESULTS The metaphysis and epiphysis had 83-123% greater total bone volume and 14-16% greater trabecular number than the diaphysis (both P < 0.0001). The erosion index was significantly higher at the diaphysis than the metaphysis and epiphysis (both P < 0.01). The most elderly volunteers had lower trabecular number (<66 years mean 0.29 ± 0.01; ≥66 years, 0.27 ± 0.02, P < 0.05) and higher erosion index (<66 years mean 1.18 ± 0.17; age ≥66 years, mean 1.42 ± 0.46, P < 0.05) at the epiphysis; differences not detected by total trabecular bone volume. CONCLUSION 7T MRI reveals trabecular bone microarchitecture varies depending on scan location at the end-of-bone, being of overall higher quality distally (epiphysis) than proximally (diaphysis). Age-related differences in trabecular microarchitecture can be detected by 7T MRI. The results highlight the potential sensitivity of 7T MRI to microarchitectural differences and the potential importance of standardizing scan location for future clinical studies of fracture risk or treatment response. LEVEL OF EVIDENCE 3 J. Magn. Reson. Imaging 2017;45:872-878.
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Affiliation(s)
- Lindsay M Griffin
- Department of Radiology, New York University, New York, New York, USA
| | - Stephen Honig
- Department of Medicine, New York University, New York, New York, USA
| | - Cheng Chen
- University of Iowa, Iowa City, Iowa, USA
| | | | - Ravinder Regatte
- Department of Radiology, New York University, New York, New York, USA
| | - Gregory Chang
- Department of Radiology, New York University, New York, New York, USA
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