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Samant M, Krings JG, Lew D, Goss CW, Koch T, McGregor MC, Boomer J, Hall CS, Schechtman KB, Sheshadri A, Peterson S, Erzurum S, DePew Z, Morrow LE, Hogarth DK, Tejedor R, Trevor J, Wechsler ME, Sam A, Shi X, Choi J, Castro M. Use of Quantitative CT Imaging to Identify Bronchial Thermoplasty Responders. Chest 2024; 165:775-784. [PMID: 38123124 PMCID: PMC11026166 DOI: 10.1016/j.chest.2023.12.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 11/12/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Bronchial thermoplasty (BT) is a treatment for patients with poorly controlled, severe asthma. However, predictors of treatment response to BT are defined poorly. RESEARCH QUESTION Do baseline radiographic and clinical characteristics exist that predict response to BT? STUDY DESIGN AND METHODS We conducted a longitudinal prospective cohort study of participants with severe asthma receiving BT across eight academic medical centers. Participants received three separate BT treatments and were monitored at 3-month intervals for 1 year after BT. Similar to prior studies, a positive response to BT was defined as either improvement in Asthma Control Test results of ≥ 3 or Asthma Quality of Life Questionnaire of ≥ 0.5. Regression analyses were used to evaluate the association between pretreatment clinical and quantitative CT scan measures with subsequent BT response. RESULTS From 2006 through 2017, 88 participants received BT, with 70 participants (79.5%) identified as responders by Asthma Control Test or Asthma Quality of Life Questionnaire criteria. Responders were less likely to undergo an asthma-related ICU admission in the prior year (3% vs 25%; P = .01). On baseline quantitative CT imaging, BT responders showed less air trapping percentage (OR, 0.90; 95% CI, 0.82-0.99; P = .03), a greater Jacobian determinant (OR, 1.49; 95% CI, 1.05-2.11), greater SD of the Jacobian determinant (OR, 1.84; 95% CI, 1.04-3.26), and greater anisotropic deformation index (OR, 3.06; 95% CI, 1.06-8.86). INTERPRETATION To our knowledge, this is the largest study to evaluate baseline quantitative CT imaging and clinical characteristics associated with BT response. Our results show that preservation of normal lung expansion, indicated by less air trapping, a greater magnitude of isotropic expansion, and greater within-lung spatial variation on quantitative CT imaging, were predictors of future BT response. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT01185275; URL: www. CLINICALTRIALS gov.
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Affiliation(s)
- Maanasi Samant
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - James G Krings
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - Daphne Lew
- Division of Biostatistics, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - Charles W Goss
- Division of Biostatistics, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - Tammy Koch
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - Mary Clare McGregor
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - Jonathan Boomer
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS
| | - Chase S Hall
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS
| | - Ken B Schechtman
- Division of Biostatistics, Washington University in Saint Louis School of Medicine, Saint Louis, MO
| | - Ajay Sheshadri
- Division of Pulmonary Critical Care Medicine, Department of Medicine, University of Texas MD Anderson Cancer Center, Houston, TX
| | | | - Serpil Erzurum
- Lerner Research Institute and the Respiratory Institute, Cleveland Clinic, Cleveland, OH
| | - Zachary DePew
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Creighton University Medical Center, Omaha, NE
| | - Lee E Morrow
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Creighton University Medical Center, Omaha, NE
| | - D Kyle Hogarth
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, IL
| | - Richard Tejedor
- Division of Pulmonary and Critical Care, Department of Medicine, LSU Health Sciences Center, New Orleans, LA
| | - Jennifer Trevor
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | | | - Afshin Sam
- Division of Pulmonary and Critical Care, Department of Medicine, University of Arizona, Tuscon, AZ
| | - Xiaosong Shi
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS
| | - Jiwoong Choi
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS
| | - Mario Castro
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS.
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Liu Y, Lu C, Chen W, Liu Z, Wu S, Ye H, Lv Y, Peng Z, Wang P, Li G, Tan B, Wu G. Clinical evaluation of pulmonary quantitative computed tomography parameters for diagnosing eosinophilic chronic obstructive pulmonary disease: Characteristics and diagnostic performance. Health Sci Rep 2024; 7:e1734. [PMID: 38500635 PMCID: PMC10944982 DOI: 10.1002/hsr2.1734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 10/27/2023] [Accepted: 11/05/2023] [Indexed: 03/20/2024] Open
Abstract
Aims To investigate the characteristics and diagnostic performance of quantitative computed tomography (QCT) parameters in eosinophilic chronic obstructive pulmonary disease (COPD) patients. Methods High-resolution CT scans of COPD patients were retrospectively analyzed, and various emphysematous parenchyma measurements, including lung volume (LC), lung mean density (LMD), lung standard deviation (LSD), full-width half maximum (FWHM), and lung relative voxel number (LRVN) were performed. The QCT parameters were compared between eosinophilic and noneosinophilic COPD patients, using a definition of eosinophilic COPD as blood eosinophil values ≥ 300 cells·µL-1 on at least three times. Receiver operating characteristic curves and area under the curve (ROC-AUC) and python were used to evaluate discriminative efficacy of QCT. Results Noneosinophilic COPD patients had a significantly lower TLMD (-846.3 ± 47.9 Hounsfield Unit [HU]) and TFWHM(162.5 ± 30.6 HU) compared to eosinophilic COPD patients (-817.8 ± 54.4, 177.3 ± 33.1 HU, respectively) (p = 0.018, 0.03, respectively). Moreover, the total LC (TLC) and TLSD were significantly lower in eosinophilic COPD group (3234.4 ± 1145.8, 183.8 ± 33.9 HU, respectively) than the noneosinophilic COPD group (5600.2 ± 1248.4, 203.5 ± 20.4 HU, respectively) (p = 0.009, 0.002, respectively). The ROC-AUC values for TLC, TLMD, TLSD, and TFWHM were 0.91 (95% confidence interval [CI], 0.828-0.936), 0.66 (95% CI, 0.546-0.761), 0.64 (95% CI, 0.524-0.742), and 0.63 (95% CI, 0.511-0.731), respectively. When the TLC value was 4110 mL, the sensitivity was 90.7% (95% CI, 79.7-96.9), specificity was 77.8% (95% CI, 57.7-91.4) and accuracy was 86.4%. Notably, TLC demonstrated the highest discriminative efficiency with an F1 Score of 0.79, diagnostic Odds Ratio of 34.3 and Matthews Correlation Coefficient of 0.69, surpassing TLMD (0.55, 3.66, 0.25), TLSD (0.56, 3.95, 0.26), and TFWHM (0.56, 4.16, 0.33). Conclusion Eosinophilic COPD patients exhibit lower levels of emphysema and a more uniform density distribution throughout the lungs compared to noneosinophilic COPD patients. Furthermore, TLC demonstrated the highest diagnostic efficiency and may serve as a valuable diagnostic marker for distinguishing between the two groups.
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Affiliation(s)
- Yumeng Liu
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Chao Lu
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Wenfang Chen
- Department of Respiratory MedicineShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Zhenyu Liu
- Department of GastroenterologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Songxiong Wu
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Hai Ye
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Yungang Lv
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Zhengkun Peng
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Panying Wang
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Guangyao Li
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Biwen Tan
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
| | - Guangyao Wu
- Department of RadiologyShenzhen University General Hospital, Shenzhen University Clinical Medical AcademyShenzhenChina
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Ji Y, Chen L, Yang J, Yang X, Yang F. Quantitative assessment of airway wall thickness in COPD patients with interstitial lung abnormalities. Front Med (Lausanne) 2023; 10:1280651. [PMID: 38146423 PMCID: PMC10749311 DOI: 10.3389/fmed.2023.1280651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/24/2023] [Indexed: 12/27/2023] Open
Abstract
Background Whether the airway is involved in the pathogenesis of interstitial lung abnormalities (ILA) is not well understood. Also the impact of ILA on lung function in COPD patients remains controversial. We aimed to assess the quantitative CT measurements of airway wall thickness (AWT) and lung function according to ILA status in COPD patients. Methods 157 COPD patients discharged from our hospital from August 1, 2019 through August 31, 2022 who underwent chest CT imagings and pulmonary function tests were retrospectively enrolled. Linear regression analysis and multiple models were used to analyze associations between quantitative assessment of airway wall changes and the presence of ILA. Results In 157 COPD patients, 23 patients (14.6%) had equivocal ILA, 42 patients (26.8%) had definite ILA. The definite ILA group had the highest measurements of Pi10 (square root of theoretical airway wall area with a lumen perimeter of 10 mm), segmental AWT and segmental WA% (percentage of wall area), whereas the no ILA group had the lowest measurements of Pi10, segmental AWT and segmental WA%. In the adjusted analyses (adjusted by age, sex, body mass index, smoking intensity, COPD GOLD stage, lung function, slice thickness and scanner type), compared to COPD patients without ILA, the measurements of Pi10, segmental AWT and segmental WA% were higher in definite ILA group with differences of 0.225 mm (p = 0.012), 0.152 mm (p < 0.001), 4.8% (p < 0.001) respectively. COPD patients with definite ILA tended to have higher FEV1% predicted, FVC% predicted and lower MMEF75/25% predicted, but there were no statistically differences among the three groups. Conclusion Our study demonstrates the higher AWT measures in COPD patients with ILA compared to the patients without ILA. These findings suggest that the airway may be involved in the pathogenesis of ILA.
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Affiliation(s)
- Yingying Ji
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Leqing Chen
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Jinrong Yang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Xiangying Yang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
| | - Fan Yang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, China
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O'Callaghan M, Duignan J, Tarling EJ, Waters DK, McStay M, O'Carroll O, Bridges JP, Redente EF, Franciosi AN, McGrath EE, Butler MW, Dodd JD, Fabre A, Murphy DJ, Keane MP, McCarthy C. Analysis of tissue lipidomics and computed tomography pulmonary fat attenuation volume (CT PFAV ) in idiopathic pulmonary fibrosis. Respirology 2023; 28:1043-1052. [PMID: 37642207 DOI: 10.1111/resp.14582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/14/2023] [Indexed: 08/31/2023]
Abstract
BACKGROUND AND OBJECTIVE There is increasing interest in the role of lipids in processes that modulate lung fibrosis with evidence of lipid deposition in idiopathic pulmonary fibrosis (IPF) histological specimens. The aim of this study was to identify measurable markers of pulmonary lipid that may have utility as IPF biomarkers. STUDY DESIGN AND METHODS IPF and control lung biopsy specimens were analysed using a unbiased lipidomic approach. Pulmonary fat attenuation volume (PFAV) was assessed on chest CT images (CTPFAV ) with 3D semi-automated lung density software. Aerated lung was semi-automatically segmented and CTPFAV calculated using a Hounsfield-unit (-40 to -200HU) threshold range expressed as a percentage of total lung volume. CTPFAV was compared to pulmonary function, serum lipids and qualitative CT fibrosis scores. RESULTS There was a significant increase in total lipid content on histological analysis of IPF lung tissue (23.16 nmol/mg) compared to controls (18.66 mol/mg, p = 0.0317). The median CTPFAV in IPF was higher than controls (1.34% vs. 0.72%, p < 0.001) and CTPFAV correlated significantly with DLCO% predicted (R2 = 0.356, p < 0.0001) and FVC% predicted (R2 = 0.407, p < 0.0001) in patients with IPF. CTPFAV correlated with CT features of fibrosis; higher CTPFAV was associated with >10% reticulation (1.6% vs. 0.94%, p = 0.0017) and >10% honeycombing (1.87% vs. 1.12%, p = 0.0003). CTPFAV showed no correlation with serum lipids. CONCLUSION CTPFAV is an easily quantifiable non-invasive measure of pulmonary lipids. In this pilot study, CTPFAV correlates with pulmonary function and radiological features of IPF and could function as a potential biomarker for IPF disease severity assessment.
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Affiliation(s)
- Marissa O'Callaghan
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
- School of Medicine, University College Dublin, Dublin, Ireland
| | - John Duignan
- Department of Radiology, St. Vincent's University Hospital, Dublin, Ireland
| | - Elizabeth J Tarling
- Division of Cardiology, University of California, Los Angeles, California, USA
| | - Darragh K Waters
- Department of Radiology, St. Vincent's University Hospital, Dublin, Ireland
| | - Megan McStay
- Department of Radiology, St. Vincent's University Hospital, Dublin, Ireland
| | - Orla O'Carroll
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
| | - James P Bridges
- Department of Medicine, National Jewish Health, Denver, Colorado, USA
| | | | - Alessandro N Franciosi
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
- School of Medicine, University College Dublin, Dublin, Ireland
| | - Emmet E McGrath
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
- School of Medicine, University College Dublin, Dublin, Ireland
| | - Marcus W Butler
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
- School of Medicine, University College Dublin, Dublin, Ireland
| | - Jonathan D Dodd
- School of Medicine, University College Dublin, Dublin, Ireland
- Department of Radiology, St. Vincent's University Hospital, Dublin, Ireland
| | - Aurelie Fabre
- School of Medicine, University College Dublin, Dublin, Ireland
- Department of Histopathology, St. Vincent's University Hospital, Dublin, Ireland
| | - David J Murphy
- School of Medicine, University College Dublin, Dublin, Ireland
- Department of Radiology, St. Vincent's University Hospital, Dublin, Ireland
| | - Michael P Keane
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
- School of Medicine, University College Dublin, Dublin, Ireland
| | - Cormac McCarthy
- Department of Respiratory Medicine, St. Vincent's University Hospital, Dublin, Ireland
- School of Medicine, University College Dublin, Dublin, Ireland
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Hu WT, Chen W, Zhou M, Fan J, Yan F, Liu B, Lu FY, Chen R, Guo Y, Yang W. Quantitative analyzes of the variability in airways via four-dimensional dynamic ventilation CT in patients with chronic obstructive pulmonary disease: correlation with spirometry data and severity of airflow limitation. J Thorac Dis 2023; 15:4775-4786. [PMID: 37868900 PMCID: PMC10586961 DOI: 10.21037/jtd-23-573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/04/2023] [Indexed: 10/24/2023]
Abstract
Background In chronic obstructive pulmonary disease (COPD) patients, the diagnosis and assessment of disease severity are mainly based on spirometry, which may lead to misjudgments due to poor patient compliance. Thoracic four-dimensional dynamic ventilation computed tomography (4D-CT) provides more airway data approximating true physiological function than conventional CT. We aimed to determine dynamic changes in airways to elucidate the pathological mechanism underlying COPD and predict the severity of airflow limitation in patients. Methods Forty-two COPD patients underwent 4D-CT and spirometry. The minimum lumen diameter changed with the breathing cycle in 4th-generation airways and was continuously measured in the apical (RB1), lateral (RB4) and posterior basal segments (RB10) of the right lung. The minimum lumen diameter in the peak inspiration and peak expiration as well as the peak expiratory/peak inspiratory ratio (E/I ratio), and dynamic coefficient of variance (CV) were calculated. Results Correlations of FEV1% with the CV of minimum lumen diameter in RB1 (ρ=-0.473, P=0.002) and in RB10 (ρ=-0.480, P=0.005) were observed, suggesting that the dynamic variability in 4th-generation airways was associated with airflow limitation in COPD patients. The CV of the minimum lumen diameter in RB1 significantly differed between the GOLD I + II and GOLD III + IV groups {8.59 [interquartile range (IQR), 6.63-14.86] vs. 14.64 (10.65-25.88), respectively; P=0.016}, suggesting that the dynamic CV in RB1 increased significantly in the GOLD III + IV group, which had worse pulmonary ventilation function. Based on the receiver operating characteristic (ROC) curve analysis, CV-RB1 predicted FEV1% <50% with an optimal cut-off of 9.43% [sensitivity 85.7%, specificity 57.1%, area under the curve (AUC) 0.717]. Conclusions 4D-CT might be an available method to help diagnose and evaluate the severity of COPD.
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Affiliation(s)
- Wei-Ting Hu
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Wei Chen
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Min Zhou
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Jing Fan
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fuhua Yan
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Bing Liu
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Fang-Ying Lu
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Rong Chen
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Yi Guo
- Department of Pulmonary and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Respiratory Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Emergency Prevention, Diagnosis and Treatment of Respiratory Infectious Diseases, Shanghai, China
| | - Wenjie Yang
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Dettmer S, Weinheimer O, Sauer-Heilborn A, Lammers O, Wielpütz MO, Fuge J, Welte T, Wacker F, Ringshausen FC. Qualitative and quantitative evaluation of computed tomography changes in adults with cystic fibrosis treated with elexacaftor-tezacaftor-ivacaftor: a retrospective observational study. Front Pharmacol 2023; 14:1245885. [PMID: 37808186 PMCID: PMC10552920 DOI: 10.3389/fphar.2023.1245885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 09/11/2023] [Indexed: 10/10/2023] Open
Abstract
Introduction: The availability of highly effective triple cystic fibrosis transmembrane conductance regulator (CFTR) modulator combination therapy with elexacaftor-tezacaftor-ivacaftor (ETI) has improved pulmonary outcomes and quality of life of people with cystic fibrosis (pwCF). The aim of this study was to assess computed tomography (CT) changes under ETI visually with the Brody score and quantitatively with dedicated software, and to correlate CT measures with parameters of clinical response. Methods: Twenty two adult pwCF with two consecutive CT scans before and after ETI treatment initiation were retrospectively included. CT was assessed visually employing the Brody score and quantitatively by YACTA, a well-evaluated scientific software computing airway dimensions and lung parenchyma with wall percentage (WP), wall thickness (WT), lumen area (LA), bronchiectasis index (BI), lung volume and mean lung density (MLD) as parameters. Changes in CT metrics were evaluated and the visual and quantitative parameters were correlated with each other and with clinical changes in sweat chloride concentration, spirometry [percent predicted of forced expiratory volume in one second (ppFEV1)] and body mass index (BMI). Results: The mean (SD) Brody score improved with ETI [55 (12) vs. 38 (15); p < 0.001], incl. sub-scores for mucus plugging, peribronchial thickening, and parenchymal changes (all p < 0.001), but not for bronchiectasis (p = 0.281). Quantitatve WP (p < 0.001) and WT (p = 0.004) were reduced, conversely LA increased (p = 0.003), and BI improved (p = 0.012). Lung volume increased (p < 0.001), and MLD decreased (p < 0.001) through a reduction of ground glass opacity areas (p < 0.001). Changes of the Brody score correlated with those of quantitative parameters, exemplarily WT with the sub-score for mucus plugging (r = 0.730, p < 0.001) and peribronchial thickening (r = 0.552, p = 0.008). Changes of CT parameters correlated with those of clinical response parameters, in particular ppFEV1 with the Brody score (r = -0.606, p = 0.003) and with WT (r = -0.538, p = 0.010). Discussion: Morphological treatment response to ETI can be assessed using the Brody score as well as quantitative CT parameters. Changes in CT correlated with clinical improvements. The quantitative analysis with YACTA proved to be an objective, reproducible and simple method for monitoring lung disease, particularly with regard to future interventional clinical trials.
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Affiliation(s)
- Sabine Dettmer
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Oliver Weinheimer
- Department of Diagnostic and Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, Heidelberg, Germany
| | - Annette Sauer-Heilborn
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
| | - Oliver Lammers
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Mark O. Wielpütz
- Department of Diagnostic and Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, Heidelberg, Germany
| | - Jan Fuge
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
| | - Tobias Welte
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
| | - Frank Wacker
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Felix C. Ringshausen
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
- Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, Hannover, Germany
- European Reference Network on Rare and Complex Respiratory Diseases (ERN-LUNG), Frankfurt, Germany
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Shi G, Quevedo Gonzalez FJ, Breighner RE, Carrino JA, Siewerdsen JH, Zbijewski W. Effects of non-stationary blur on texture biomarkers of bone using Ultra-High Resolution CT. Proc SPIE Int Soc Opt Eng 2023; 12468:1246813. [PMID: 38226358 PMCID: PMC10788132 DOI: 10.1117/12.2654304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Purpose To advance the development of radiomic models of bone quality using the recently introduced Ultra-High Resolution CT (UHR CT), we investigate inter-scan reproducibility of trabecular bone texture features to spatially-variant azimuthal and radial blurs associated with focal spot elongation and gantry rotation. Methods The UHR CT system features 250×250 μm detector pixels and an x-ray source with a 0.4×0.5 mm focal spot. Visualization of details down to ~150 μm has been reported for this device. A cadaveric femur was imaged on UHR CT at three radial locations within the field-of-view: 0 cm (isocenter), 9 cm from the isocenter, and 18 cm from the isocenter; we expect the non-stationary blurs to worsen with increasing radial displacement. Gray level cooccurrence (GLCM) and gray level run length (GLRLM) texture features were extracted from 237 trabecular regions of interest (ROIs, 5 cm diameter) placed at corresponding locations in the femoral head in scans obtained at the different shifts. We evaluated concordance correlation coefficient (CCC) between texture features at 0 cm (reference) and at 9 cm and 18 cm. We also investigated whether the spatially-variant blurs affect K-means clustering of trabecular bone ROIs based on their texture features. Results The average CCCs (against the 0 cm reference) for GLCM and GLRM features were ~0.7 at 9 cm. At 18 cm, the average CCCs were reduced to ~0.17 for GLCM and ~0.26 for GLRM. The non-stationary blurs are incorporated in radiomic features of cancellous bone, leading to inconsistencies in clustering of trabecular ROIs between different radial locations: an intersection-over-union overlap of corresponding (most similar) clusters between 0 cm and 9 cm shift was >70%, but dropped to <60% for the majority of corresponding clusters between 0 cm and 18 cm shift. Conclusion Non-stationary CT system blurs reduce inter-scan reproducibility of texture features of trabecular bone in UHR CT, especially for locations >15 cm from the isocenter. Radiomic models of bone quality derived from UHR CT measurements at isocenter might need to be revised before application in peripheral body sites such as the hips.
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Affiliation(s)
- G Shi
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
| | - F J Quevedo Gonzalez
- Department of Biomechanics, Hospital for Special Surgery, New York, NY USA 10021
| | - R E Breighner
- Department of Biomechanics, Hospital for Special Surgery, New York, NY USA 10021
| | - J A Carrino
- Hospital for Special Surgery, Radiology & Imaging, New York, NY USA 10021
| | | | - W Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
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Wang Y, Chai L, Chen Y, Liu J, Wang Q, Zhang Q, Qiu Y, Li D, Chen H, Shen N, Shi X, Wang J, Xie X, Li M. Quantitative CT parameters correlate with lung function in chronic obstructive pulmonary disease: A systematic review and meta-analysis. Front Surg 2023; 9:1066031. [PMID: 36684267 PMCID: PMC9845891 DOI: 10.3389/fsurg.2022.1066031] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 11/14/2022] [Indexed: 01/06/2023] Open
Abstract
Objective This study aimed to analyze the correlation between quantitative computed tomography (CT) parameters and airflow obstruction in patients with COPD. Methods PubMed, Embase, Cochrane and Web of Knowledge were searched by two investigators from inception to July 2022, using a combination of pertinent items to discover articles that investigated the relationship between CT measurements and lung function parameters in patients with COPD. Five reviewers independently extracted data, and evaluated it for quality and bias. The correlation coefficient was calculated, and heterogeneity was explored. The following CT measurements were extracted: percentage of lung attenuation area <-950 Hounsfield Units (HU), mean lung density, percentage of airway wall area, air trapping index, and airway wall thickness. Two airflow obstruction parameters were extracted: forced expiratory volume in the first second as a percentage of prediction (FEV1%pred) and FEV1 divided by forced expiratory volume lung capacity. Results A total of 141 studies (25,214 participants) were identified, which 64 (6,341 participants) were suitable for our meta-analysis. Results from our analysis demonstrated that there was a significant correlation between quantitative CT parameters and lung function. The absolute pooled correlation coefficients ranged from 0.26 (95% CI, 0.18 to 0.33) to 0.70 (95% CI, 0.65 to 0.75) for inspiratory CT and 0.56 (95% CI, 0.51 to 0.60) to 0.74 (95% CI, 0.68 to 0.80) for expiratory CT. Conclusions Results from this analysis demonstrated that quantitative CT parameters are significantly correlated with lung function in patients with COPD. With recent advances in chest CT, we can evaluate morphological features in the lungs that cannot be obtained by other clinical indices, such as pulmonary function tests. Therefore, CT can provide a quantitative method to advance the development and testing of new interventions and therapies for patients with COPD.
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9
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Mand S, Telfer S, Battan S, Brunnquell CL, Linnau KF, Zamora D, Kleweno CP. Assessment of regional sacral bone quality: A step towards patient-specific fracture fixation. J Orthop Res 2023; 41:141-149. [PMID: 35299283 DOI: 10.1002/jor.25329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 01/07/2022] [Accepted: 03/13/2022] [Indexed: 02/04/2023]
Abstract
Characterizing changes in sacral bone density could help us to inform instrumentation choices for procedures involving the sacrum. The aim of this study is to provide detailed maps of changes in sacral bone density across a series of patients using opportunistic quantitative computed tomography (QCT). We hypothesized that there would be significant differences in local cortical and trabecular bone density associated with age and sex. Fifty-four three-dimensional sacral models were segmented from routine clinical computed tomography scans, and detailed bone density estimates were derived for each bone using a calibrated opportunistic QCT approach. The effects of age and sex on cortical and trabecular bone density were determined across the sample. Overall cortical bone loss averaged 2.1 and 0.9 mg/cc per year, and trabecular bone loss was 1.6 and 0.7 mg/cc for female and males, respectively. Several regions had loss rates several times greater. Areas that were significantly affected by age included the vertebral bodies, bilateral ala, apex, and areas adjacent to both the anterior and posterior sacral foramina. Areas that were significantly affected by sex were the anterior sacral promontory, aspects of the ala. Bone density distribution across the sacrum changes nonuniformly due to factors including sex and age. Despite these overall trends, there remains significant variability between individuals. Clinical significance: This study provides detailed bone density information for both cortical and trabecular bone that could assist orthopaedic surgeons in planning surgical approaches to sacral fracture fixation.
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Affiliation(s)
- Simran Mand
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, USA
| | - Scott Telfer
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, USA
| | - Shamele Battan
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, USA
| | | | - Ken F Linnau
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - David Zamora
- Department of Radiology, University of Washington, Seattle, Washington, USA
| | - Conor P Kleweno
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, USA
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10
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Grenier PA, Brun AL, Mellot F. The Potential Role of Artificial Intelligence in Lung Cancer Screening Using Low-Dose Computed Tomography. Diagnostics (Basel) 2022; 12:diagnostics12102435. [PMID: 36292124 PMCID: PMC9601207 DOI: 10.3390/diagnostics12102435] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/04/2022] [Accepted: 10/06/2022] [Indexed: 11/16/2022] Open
Abstract
Two large randomized controlled trials of low-dose CT (LDCT)-based lung cancer screening (LCS) in high-risk smoker populations have shown a reduction in the number of lung cancer deaths in the screening group compared to a control group. Even if various countries are currently considering the implementation of LCS programs, recurring doubts and fears persist about the potentially high false positive rates, cost-effectiveness, and the availability of radiologists for scan interpretation. Artificial intelligence (AI) can potentially increase the efficiency of LCS. The objective of this article is to review the performances of AI algorithms developed for different tasks that make up the interpretation of LCS CT scans, and to estimate how these AI algorithms may be used as a second reader. Despite the reduction in lung cancer mortality due to LCS with LDCT, many smokers die of comorbid smoking-related diseases. The identification of CT features associated with these comorbidities could increase the value of screening with minimal impact on LCS programs. Because these smoking-related conditions are not systematically assessed in current LCS programs, AI can identify individuals with evidence of previously undiagnosed cardiovascular disease, emphysema or osteoporosis and offer an opportunity for treatment and prevention.
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Affiliation(s)
- Philippe A. Grenier
- Department of Clinical Research and Innovation, Hôpital Foch, 92150 Suresnes, France
- Correspondence:
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11
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Guo F, Huang J, Hu Y, Qiu J, Zhang H, Zhang W, Cheng Y, Liao J, Wang G. Clinical outcomes and quantitative CT analysis after bronchoscopic lung volume reduction using valves for advanced emphysema. J Thorac Dis 2022; 14:1922-1932. [PMID: 35813714 PMCID: PMC9264089 DOI: 10.21037/jtd-21-1734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 05/09/2022] [Indexed: 12/04/2022]
Abstract
Background Bronchoscopic lung volume reduction (BLVR) using Zephyr endobronchial valve (EBV) and intrabronchial valve (IBV) has been shown to improve lung function and exercise capacity in severe emphysema. However, changes in airway structures and whether these are related to the clinical improvements remain unclear. Methods A retrospective study was performed on patients treated with BLVR. We compared changes in 2nd-, 3rd-, and 4th-generation bronchial structures after therapy, including wall thickness (WT), percentage of wall thickness (WT%), intraluminal area (LA), wall area (WA), and WA%. Responder and non-responder subgroup analysis according to minimum clinically important difference (MCID) which was defined as an improvement of 15% in forced expiratory volume in 1 s (FEV1) and 26 m in 6 min walk distance (6MWD) was conducted. Results Of the 19 patients, 11 were treated with EBV and 8 with IBV. In ipsilateral non-target lobes, WT% decreased significantly in 3rd-generation bronchi at 1 month, 3, and 6 months, as well as their WA% at 1 month and 6 months. Non-responders, who were unable to achieve MCID, showed no consistent bronchial wall changes. And their LA of 3rd-generation bronchi decreased especially at 1 month. After BLVR, the target lobe volume decreased significantly until 12 months of follow-up. The volume of ipsilateral lobes could increase correspondingly and achieve the best improvements at 6 months. The contralateral lung volume showed slight amelioration but there was no statistical significance. Conclusions Both airway structures and lung volumes showed changes after BLVR. The 3rd- and 4th-bronchial walls tend to be thinner, which were consistent with clinical improvements. Further studies are needed to prove this conclusion and find detect potential mechanics.
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Affiliation(s)
- Fangfang Guo
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Junfang Huang
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Yan Hu
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Jianxing Qiu
- Department of Radiology, Peking University First Hospital, Beijing, China
| | - Hong Zhang
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Wei Zhang
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Yuan Cheng
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Jiping Liao
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
| | - Guangfa Wang
- Department of Pulmonary and Critical Care Medicine, Peking University First Hospital, Beijing, China
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12
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Hatabu H, Barile M. Detection of Pulmonary Congestion in Heart Failure With Preserved Ejection Fraction Using Quantitative Chest CT. JACC Cardiovasc Imaging 2022; 15:638-640. [PMID: 35393066 DOI: 10.1016/j.jcmg.2022.01.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 01/13/2022] [Indexed: 10/18/2022]
Affiliation(s)
- Hiroto Hatabu
- Center for Pulmonary Functional Imaging, Department of Radiology, Brigham and Women's Hospital, Boston, Massachusetts, USA.
| | - Maria Barile
- Department of Radiology at University of Massachusetts Memorial Medical Center, Worcester, Massachusetts, USA
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13
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Lv X, Hu H, Shen C, Zhang X, Yan L, Zhang S, Guo Y. Risk Factors Associated With Lower Bone Mineral Density in Primary Aldosteronism Patients. Front Endocrinol (Lausanne) 2022; 13:884302. [PMID: 35784563 PMCID: PMC9245341 DOI: 10.3389/fendo.2022.884302] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
PURPOSE The association between primary aldosteronism (PA) and lower bone mineral density (BMD) has raised a concern, but the contributing factors remain unclear. We aim to explore the risk factors for lower BMD in PA patients. METHODS We analyzed and compared the data of 60 PA patients with 60 matched essential hypertension (EH) patients. BMD, bone metabolites, and several oxidative stress and inflammation indicators-including C-reactive protein (CRP), superoxide dismutase (SOD), total bilirubin (TBIL), mean platelet volume (MPV), etc.-were assessed and compared in PA and EH patients. Bivariate correlation analysis and multivariate linear regression analysis were performed to explore the factors associated with BMD in PA patients. RESULTS The BMD measured by quantitative computed tomography in PA patients was lower than that in EH patients (141.9 ± 34.0 vs. 158.9 ± 55.9 g/cm3, p = 0.047), especially in patients less than 50 years old. BMD was independently negatively associated with age (standardized β = -0.581, p < 0.001), serum phosphorus (standardized β = -0.203, p = 0.008), urinary calcium excretion (standardized β = -0.185, p = 0.031), and MPV (standardized β = -0.172, p = 0.043) and positively associated with SOD (standardized β = 0.205, p = 0.011) and TBIL (standardized β = 0.212, p = 0.015). CONCLUSIONS The PA patients showed a lower BMD than the EH patients, which was associated with age, serum phosphorus, urinary calcium excretion, MPV, SOD, and TBIL. These variables might be potential markers for the assessment of bone loss and efficacy of treatments in PA patients.
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Affiliation(s)
- Xiaomei Lv
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Huijun Hu
- Department of Radiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Chuyu Shen
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiaoyun Zhang
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Li Yan
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Shaoling Zhang
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Ying Guo
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- *Correspondence: Ying Guo,
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14
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Stayman JW, Tivnan M, Wang W. Spectral CT using a fine grid structure and varying x-ray incidence angle. Med Phys 2021; 48:6412-6420. [PMID: 34151442 PMCID: PMC10771732 DOI: 10.1002/mp.14853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 02/22/2021] [Accepted: 03/08/2021] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Interest in spectral computed tomography (CT) for diagnostics and therapy evaluation has been growing. Data acquisitions with distinct spectral sensitivities provide the ability to discriminate multiple materials, quantitative density estimates, and reduced artifacts due to energy dependencies. We introduce a novel spectral CT concept that includes a fine-pitch grid structure for prefiltration of the x-ray beam. METHODS We develop physical models for grid designs and illustrate the basic operating principles wherein small angulations of the incident x rays results significant filtration and spectral shaping of the beam. We fabricate a prototype grid with tungsten lamellae. We compare x-ray spectra induced by this filter as a function of incidence angle in both simulation students and in physical measurements. The grid is also integrated onto a CT test bench where we scanned an iodinated phantom with clinically relevant concentrations (5, 10, 20, and 50 mgI/mL) to demonstrate the ability to perform spectral CT acquisitions and material decomposition. RESULTS X-ray spectrometer measurements reveal diverse and controllable spectral shaping with small angle changes that are in agreement with simulation studies. Critical angles where the characteristics of the induced spectrum changes dramatically are identified. Reconstructions of projection data for two angulations separated by 2° was reconstructed and material decomposition into iodine and water images shows good agreement with the known iodine concentrations. CONCLUSIONS This work demonstrates the feasibility of the grid-based approach to enable spectral CT data acquisitions and accurate material decompositions. On-going and future studies will investigate the potential of this novel concept as a relatively simple upgrade to standard energy-integrating CT.
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Affiliation(s)
- J. Webster Stayman
- Department of Biomedical, Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Matthew Tivnan
- Department of Biomedical, Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Wenying Wang
- Department of Biomedical, Engineering, Johns Hopkins University, Baltimore, MD, USA
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15
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Chabi ML, Dana O, Kennel T, Gence-Breney A, Salvator H, Ballester MC, Vasse M, Brun AL, Mellot F, Grenier PA. Automated AI-Driven CT Quantification of Lung Disease Predicts Adverse Outcomes in Patients Hospitalized for COVID-19 Pneumonia. Diagnostics (Basel) 2021; 11:diagnostics11050878. [PMID: 34069115 PMCID: PMC8156322 DOI: 10.3390/diagnostics11050878] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/03/2021] [Accepted: 05/09/2021] [Indexed: 12/16/2022] Open
Abstract
The purpose of our work was to assess the independent and incremental value of AI-derived quantitative determination of lung lesions extent on initial CT scan for the prediction of clinical deterioration or death in patients hospitalized with COVID-19 pneumonia. 323 consecutive patients (mean age 65 ± 15 years, 192 men), with laboratory-confirmed COVID-19 and an abnormal chest CT scan, were admitted to the hospital between March and December 2020. The extent of consolidation and all lung opacities were quantified on an initial CT scan using a 3D automatic AI-based software. The outcome was known for all these patients. 85 (26.3%) patients died or experienced clinical deterioration, defined as intensive care unit admission. In multivariate regression based on clinical, biological and CT parameters, the extent of all opacities, and extent of consolidation were independent predictors of adverse outcomes, as were diabetes, heart disease, C-reactive protein, and neutrophils/lymphocytes ratio. The association of CT-derived measures with clinical and biological parameters significantly improved the risk prediction (p = 0.049). Automated quantification of lung disease at CT in COVID-19 pneumonia is useful to predict clinical deterioration or in-hospital death. Its combination with clinical and biological data improves risk prediction.
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Affiliation(s)
- Marie Laure Chabi
- Department of Medical Imaging, Foch Hospital, 92150 Suresnes, France; (M.L.C.); (O.D.); (A.G.-B.); (A.L.B.); (F.M.)
| | - Ophélie Dana
- Department of Medical Imaging, Foch Hospital, 92150 Suresnes, France; (M.L.C.); (O.D.); (A.G.-B.); (A.L.B.); (F.M.)
| | - Titouan Kennel
- Department of Clinical Research and Innovation, Foch Hospital, 92150 Suresnes, France;
| | - Alexia Gence-Breney
- Department of Medical Imaging, Foch Hospital, 92150 Suresnes, France; (M.L.C.); (O.D.); (A.G.-B.); (A.L.B.); (F.M.)
| | - Hélène Salvator
- Department of Pneumology, Foch Hospital, UFR Santé Simone Veil UVSQ Paris-Saclay University, 92150 Suresnes, France;
| | | | - Marc Vasse
- Department of Clinical Biology, Foch Hospital, 92150 Suresnes, France;
- INSERM, UMRS 1176, Paris-Saclay University, 94270 Le Kremlin-Bicêtre, France
| | - Anne Laure Brun
- Department of Medical Imaging, Foch Hospital, 92150 Suresnes, France; (M.L.C.); (O.D.); (A.G.-B.); (A.L.B.); (F.M.)
| | - François Mellot
- Department of Medical Imaging, Foch Hospital, 92150 Suresnes, France; (M.L.C.); (O.D.); (A.G.-B.); (A.L.B.); (F.M.)
| | - Philippe A. Grenier
- Department of Clinical Research and Innovation, Foch Hospital, 92150 Suresnes, France;
- Correspondence:
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16
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Guo HH, Persson M, Weinheimer O, Rosenberg J, Robinson TE, Wang J. A calibration CT mini-lung-phantom created by 3-D printing and subtractive manufacturing. J Appl Clin Med Phys 2021; 22:183-190. [PMID: 33949078 PMCID: PMC8200432 DOI: 10.1002/acm2.13263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 01/15/2021] [Accepted: 03/30/2021] [Indexed: 11/06/2022] Open
Abstract
We describe the creation and characterization of a calibration CT mini‐lung‐phantom incorporating simulated airways and ground‐glass densities. Ten duplicate mini‐lung‐phantoms with Three‐Dimensional (3‐D) printed tubes simulating airways and gradated density polyurethane foam blocks were designed and built. Dimensional accuracy and CT numbers were measured using micro‐CT and clinical CT scanners. Micro‐CT images of airway tubes demonstrated an average dimensional variation of 0.038 mm from nominal values. The five different densities of incorporated foam blocks, simulating ground‐glass, showed mean CT numbers (±standard deviation) of −897.0 ± 1.5, −844.1 ± 1.5, −774.1 ± 2.6, −695.3 ± 1.6, and −351.0 ± 3.7 HU, respectively. Three‐Dimensional printing and subtractive manufacturing enabled rapid, cost‐effective production of ground‐truth calibration mini‐lung‐phantoms with low inter‐sample variation that can be scanned simultaneously with the patient undergoing lung quantitative CT.
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Affiliation(s)
- H Henry Guo
- Department of Radiology, Stanford Medical Center, Stanford, CA, USA
| | - Mats Persson
- Department of Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Oliver Weinheimer
- Department of Radiology, University of Heidelberg, Heidelberg, Germany
| | | | - Terry E Robinson
- Emeritus, Department of Pediatrics, Stanford Medical Center, Stanford, CA, USA
| | - Jia Wang
- Environmental Health and Safety, Stanford University, Stanford, CA, USA
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Pennati F, Walkup LL, Chhabra A, Towe C, Myers K, Aliverti A, Woods JC. Quantitative inspiratory-expiratory chest CT to evaluate pulmonary involvement in pediatric hematopoietic stem-cell transplantation patients. Pediatr Pulmonol 2021; 56:1026-1035. [PMID: 33314762 PMCID: PMC8721603 DOI: 10.1002/ppul.25223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 11/11/2020] [Accepted: 12/06/2020] [Indexed: 12/18/2022]
Abstract
Pulmonary complications following allogeneic hematopoietic stem-cell transplantation (HSCT) are a significant source of morbidity and complications may arise from a myriad of infectious and noninfectious sources. These complications may occur soon or many months post-transplantation and can have a broad range of outcomes. Surveillance for pulmonary involvement in the pediatric HSCT population can be challenging due to poor compliance with clinical pulmonary function testing, primarily spirometry, and there may be a role for clinical imaging to provide an additional means of monitoring, particularly in the era of clinical low-dose computed tomography (CT) protocols. In this single-site, retrospective study, a review of our institution's radiological and HSCT databases was conducted to assess the utility of a quantitative CT algorithm to describe ventilation abnormalities on high-resolution chest CT scans of pediatric HSCT patients. Thirteen non-contrast enhanced chest CT examinations acquired both in inspiration and expiration, from 12 deceased HSCT patients (median age at HSCT 10.4 years, median days of CT 162) were selected for the analysis. Also, seven age-matched healthy controls (median age 15.5) with non-contrast-enhanced inspiration-expiration chest CT were selected for comparison. We report that, compared to healthy age-matched controls, HSCT patients had larger percentages of poorly ventilated (median, 13.5% vs. 2.3%, p < .001) and air trapped (median 12.3% vs. 0%, p < .001) regions of lung tissue, suggesting its utility as a potential screening tool. Furthermore, there was wide variation within individual HSCT patients, supporting the use of multivolume CT and quantitative analysis to describe and phenotype post-transplantation lung involvement.
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Affiliation(s)
- Francesca Pennati
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy
| | - Laura L Walkup
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Anuj Chhabra
- College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Christopher Towe
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Kasiani Myers
- Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA.,Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Andrea Aliverti
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Pediatrics, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
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Dwivedi K, Sharkey M, Condliffe R, Uthoff JM, Alabed S, Metherall P, Lu H, Wild JM, Hoffman EA, Swift AJ, Kiely DG. Pulmonary Hypertension in Association with Lung Disease: Quantitative CT and Artificial Intelligence to the Rescue? State-of-the-Art Review. Diagnostics (Basel) 2021; 11:diagnostics11040679. [PMID: 33918838 PMCID: PMC8070579 DOI: 10.3390/diagnostics11040679] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/05/2021] [Accepted: 04/05/2021] [Indexed: 12/24/2022] Open
Abstract
Accurate phenotyping of patients with pulmonary hypertension (PH) is an integral part of informing disease classification, treatment, and prognosis. The impact of lung disease on PH outcomes and response to treatment remains a challenging area with limited progress. Imaging with computed tomography (CT) plays an important role in patients with suspected PH when assessing for parenchymal lung disease, however, current assessments are limited by their semi-qualitative nature. Quantitative chest-CT (QCT) allows numerical quantification of lung parenchymal disease beyond subjective visual assessment. This has facilitated advances in radiological assessment and clinical correlation of a range of lung diseases including emphysema, interstitial lung disease, and coronavirus disease 2019 (COVID-19). Artificial Intelligence approaches have the potential to facilitate rapid quantitative assessments. Benefits of cross-sectional imaging include ease and speed of scan acquisition, repeatability and the potential for novel insights beyond visual assessment alone. Potential clinical benefits include improved phenotyping and prediction of treatment response and survival. Artificial intelligence approaches also have the potential to aid more focused study of pulmonary arterial hypertension (PAH) therapies by identifying more homogeneous subgroups of patients with lung disease. This state-of-the-art review summarizes recent QCT developments and potential applications in patients with PH with a focus on lung disease.
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Affiliation(s)
- Krit Dwivedi
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- Correspondence:
| | - Michael Sharkey
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- Radiology Department, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield S10 2JF, UK
| | - Robin Condliffe
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield S10 2JF, UK
| | - Johanna M. Uthoff
- Department of Computer Science, University of Sheffield, Sheffield S1 4DP, UK; (J.M.U.); (H.L.)
| | - Samer Alabed
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
| | - Peter Metherall
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- Radiology Department, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield S10 2JF, UK
| | - Haiping Lu
- Department of Computer Science, University of Sheffield, Sheffield S1 4DP, UK; (J.M.U.); (H.L.)
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield S1 3JD, UK
| | - Jim M. Wild
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield S1 3JD, UK
| | - Eric A. Hoffman
- Advanced Pulmonary Physiomic Imaging Laboratory, University of Iowa, C748 GH, Iowa City, IA 52242, USA;
| | - Andrew J. Swift
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- Radiology Department, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield S10 2JF, UK
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield S1 3JD, UK
| | - David G. Kiely
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK; (M.S.); (R.C.); (S.A.); (P.M.); (J.M.W.); (A.J.S.); (D.G.K.)
- Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield S10 2JF, UK
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield S1 3JD, UK
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Kaya F, Konya PŞ, Demirel E, Demirtürk N, Orhan S, Ufuk F. Visual and quantitative assessment of COVID-19 pneumonia on chest CT: The relationship with disease severity and clinical findings. Curr Med Imaging 2021; 17:1142-1150. [PMID: 33588737 DOI: 10.2174/1573405617666210215142528] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND Lungs are the primary organ of involvement of COVID-19, and the severity of pneumonia in COVID-19 patients is an important cause of morbidity and mortality. AIM We aimed to evaluate the visual and quantitative pneumonia severity on chest computed tomography (CT) in patients with coronavirus disease 2019 (COVID-19) and compare the CT findings with clinical and laboratory findings. METHODS We retrospectively evaluated adult COVID-19 patients who underwent chest CT, clinical scores, laboratory findings, and length of hospital stay. Two independent radiologists visually evaluated the pneumonia severity on chest CT (VSQS). Quantitative CT (QCT) assessment was performed using a free DICOM viewer, and the percentage of the well-aerated lung (%WAL), high-attenuation areas (%HAA) at different threshold values, and mean lung attenuation (MLA) values were calculated. The relationship between CT scores and the clinical, laboratory data, and length of hospital stay were evaluated in this cross-sectional study. The student's t-test and chi-square test were used to analyze the differences between variables. The Pearson correlation test analyzed the correlation between variables. The diagnostic performance of the variables was assessed using receiver operating characteristic (ROC) analysis was used. RESULTS The VSQS and QCT scores were significantly correlated with procalcitonin, d-dimer, ferritin, and C-reactive protein levels. Both VSQ and QCT scores were significantly correlated with disease severity (p<0.001). Among the QCT parameters, the %HAA-600 value showed the best correlation with the VSQS (r=730,p<0.001). VSQS and QCT scores had high sensitivity and specificity in distinguishing disease severity and predicting prolonged hospitalization. CONCLUSION The VSQS and QCT scores can help manage the COVID-19 and predict the duration of hospitalization.
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Affiliation(s)
- Furkan Kaya
- Afyonkarahisar Health Sciences University, Department of Radiology, Afyonkarahisar. Turkey
| | - Petek Şarlak Konya
- Afyonkarahisar Health Sciences University, Department of Infectious Disease, Afyonkarahisar. Turkey
| | - Emin Demirel
- Afyonkarahisar Health Sciences University, Department of Radiology, Afyonkarahisar. Turkey
| | - Neşe Demirtürk
- Afyonkarahisar Health Sciences University, Department of Infectious Disease, Afyonkarahisar. Turkey
| | - Semiha Orhan
- Afyonkarahisar Health Sciences University, Department of Intensive Care, Afyonkarahisar. Turkey
| | - Furkan Ufuk
- Department of Radiology, University of Pamukkale, Denizli. Turkey
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Chen P, Zha Y, Wang L, Li L, Hu L, Xing D, Liu B, Yang L, Yang Q, Liu C, Liu H, Liu W. Evaluation of Bone Marrow Texture and Trabecular Changes With Quantitative DCE-MRI and QCT in Alloxan-Induced Diabetic Rabbit Models. Front Endocrinol (Lausanne) 2021; 12:785604. [PMID: 35002967 PMCID: PMC8728072 DOI: 10.3389/fendo.2021.785604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 11/26/2021] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To investigate whether the microvascular permeability of lumbar marrow and bone trabecular changes in early-stage diabetic rabbits can be quantitatively evaluated using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), quantitative computed tomography, and texture-analyzed permeability parameter Ktrans map of DCE-MRI. MATERIALS AND METHODS This prospective study included 24 rabbits that were randomly assigned to diabetic (n = 14) and control (n = 10) groups. All rabbits underwent sagittal MRI of the lumbar region at 0, 4, 8, 12, and 16 weeks after alloxan injection. Pearson correlation coefficient was performed to determine the correlation between permeability parameter and bone mineral density (BMD). Repeated-measures ANOVA was used to analyze the changes in lumbar BMD over time in each group and the texture parameters of diabetic rabbit lumbar marrow at different time points. Mann-Whitney U rank sum test was used to compare the differences of each index between the two groups and calculate the area under the curve (AUC). RESULTS BMD was correlated with Ktrans , Kep , and Ve but not with Vp . At weeks 0-16, the BMD of the rabbits in the diabetic and normal groups was not statistically significant, but the change in BMD showed an overall downward trend. For texture analysis, entropy, energy, and Uniformized positive pixel (UPP) parameters extracted from the Ktrans map showed significant differences from week 0 to 16 between the two groups. The identification ability at 8-12 weeks was higher than that at 12-16 weeks, and the AUCs were 0.734, 0.766, and 0.734, respectively (P < 0.05 for all). CONCLUSIONS The changes in BMD measured using quantitative computed tomography occurred later than those measured using bone trabecular morphometry. Texture analysis parameters based on DCE-MRI quantitative parameter Ktrans map are feasible to identify early changes in lumbar marrow structure in diabetic rabbits.
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Affiliation(s)
- Pianpian Chen
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yunfei Zha
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
- *Correspondence: Yunfei Zha,
| | - Li Wang
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Liang Li
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lei Hu
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Dong Xing
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Baiyu Liu
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Liu Yang
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Qi Yang
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Changsheng Liu
- Department Radiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Huan Liu
- Precision Healthcare Institute, GE Healthcare, Shanghai, China
| | - Weiyin Liu
- MR Research, GE Healthcare, Shanghai, China
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21
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Song L, Leppig JA, Hubner RH, Lassen-Schmidt BC, Neumann K, Theilig DC, Feldhaus FW, Fahlenkamp UL, Hamm B, Song W, Jin Z, Doellinger F. Quantitative CT Analysis in Patients with Pulmonary Emphysema: Do Calculated Differences Between Full Inspiration and Expiration Correlate with Lung Function? Int J Chron Obstruct Pulmon Dis 2020; 15:1877-1886. [PMID: 32801683 PMCID: PMC7413697 DOI: 10.2147/copd.s253602] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 07/02/2020] [Indexed: 11/23/2022] Open
Abstract
Purpose The aim of this retrospective study was to evaluate correlations between parameters of quantitative computed tomography (QCT) analysis, especially the 15th percentile of lung attenuation (P15), and parameters of clinical tests in a large group of patients with pulmonary emphysema. Patients and Methods One hundred and seventy-two patients with pulmonary emphysema and chronic obstructive pulmonary disease (COPD) global initiative for chronic obstructive lung disease (GOLD) stage 3 or 4 were assessed by nonenhanced thin-section CT scans in full inspiratory and expiratory breath-hold, pulmonary function test (PFT), a 6-minute walk test (6MWT), and quality of life questionnaires (SGRQ and CAT). QCT parameters included total lung volume (TLV), total emphysema score (TES), and P15, all measured at inspiration (IN) and expiration (EX). Differences between inspiration and expiration were calculated for TLV (TLVDiff), TES (TESDiff), and P15 (P15Diff). Spearman correlation analysis was performed. Results CT-measured lung volume in inspiration (TLVIN) correlated strongly with spirometry-measured total lung capacity (TLC) (r=0.81, p<0.001) and moderately to strongly with residual volume (RV), forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1)/FVC (r=0.60, 0.56, and −0.49, each p<0.001). Lung volume in expiration (TLVEX) correlated moderately to strongly with TLC, RV and FEV1/FVC ratio (r=0.75, 0.66, and −0.43, each p<0.001). TES and P15 showed stronger correlations with the carbon monoxide transfer coefficient (KCO%) (r= −0.42, 0.44, both p<0.001), when measured during expiration. P15Diff correlated moderately with KCO% and carbon monoxide diffusing capacity (DLCO%) (r= 0.41, 0.40, both p<0.001). The 6MWT and most QCT parameters showed significant differences between COPD GOLD 3 and 4 groups. Conclusion Our results suggest that QCT can help predict the severity of lung function decrease in patients with pulmonary emphysema and COPD GOLD 3 or 4. Some QCT parameters, including P15EX and P15Diff, correlated moderately to strongly with parameters of pulmonary function tests.
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Affiliation(s)
- Lan Song
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
| | - Jonas A Leppig
- Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Ralf H Hubner
- Department of Internal Medicine/Infectious Diseases and Respiratory Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany
| | | | - Konrad Neumann
- Institute of Biometrics and Clinical Epidemiology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Dorothea C Theilig
- Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Felix W Feldhaus
- Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Ute L Fahlenkamp
- Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Wei Song
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
| | - Zhengyu Jin
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
| | - Felix Doellinger
- Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany
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22
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Stayman JW, Tivnan M, Gang GJ, Wang W, Shapira N, Noël PB. Grating-based Spectral CT using Small Angle X-ray Beam Deflections. Conf Proc Int Conf Image Form Xray Comput Tomogr 2020; 2020:630-633. [PMID: 33163989 PMCID: PMC7643889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Interest in spectral CT for diagnostics and therapy evaluation has been growing. Acquisitions of data from distinct energy spectra provide, among other advantages, quantitative density estimations for multiple materials. We introduce a novel spectral CT concept that includes a fine-pitch grating for prefiltration of the x-ray beam. The attenuation behavior of this grating changes significantly if x-rays are slightly angled in relation to the grating structures. To apply such an angle (i.e. switch between the different filtrations) we propose a fast, controllable, and precise solution by moving the focal spot of the x-ray tube. In this work, we performed preliminary evaluations with a grating prototype on a CT test bench. Our results include x-ray spectrometer measurements that reveal diverse and controllable spectral shaping between 4° and 6° for a specific grating design. Additional experiments with a contrast agent phantom illustrated the capability to decompose clinically relevant iodine concentrations (5, 10, 20, and 50mg/mL) - demonstrating the feasibility of the grating-based approach. Ongoing and future studies will investigate the potential of this novel concept as a relatively simple upgrade to standard energy-integrating CT.
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Affiliation(s)
- J Webster Stayman
- Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD
| | - Matthew Tivnan
- Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD
| | - Grace J Gang
- Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD
| | - Wenying Wang
- Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD
| | - Nadav Shapira
- University of Pennsylvania, Department of Radiology, Philadelphia, PA
| | - Peter B Noël
- University of Pennsylvania, Department of Radiology, Philadelphia, PA
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23
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Ma YQ, Wang W, Tivnan M, Li J, Lu M, Zhang J, Star-Lack J, Colbeth RE, Zbijewski W, Stayman JW. High-Resolution Model-based Material Decomposition for Multi-Layer Flat-Panel Detectors. Conf Proc Int Conf Image Form Xray Comput Tomogr 2020; 2020:62-64. [PMID: 33163986 PMCID: PMC7643886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work we compare a novel model-based material decomposition (MBMD) approach against a standard approach in high-resolution spectral CT using multi-layer flat-panel detectors. Physical experiments were conducted using a prototype dual-layer detector and a custom high-resolution iodine-enhanced line-pair phantom. Reconstructions were performed using three methods: traditional filtered back-projection (FBP) followed by image-domain decomposition, idealized MBMD with no blur modeling (iMBMD), and MBMD with system blur modeling (bMBMD). We find that both MBMD methods yielded higher resolution decompositions with lower noise than the FBP method, and that bMBMD further improves spatial resolution over iMBMD due to the additional blur modeling. These results demonstrate the advantages of MBMD in resolution performance and noise control over traditional methods for spectral CT. Model-based material decomposition hence has great potential in high-resolution spectral CT applications.
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Affiliation(s)
- Yiqun Q Ma
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205
| | - Wenying Wang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205
| | - Matt Tivnan
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205
| | - Junyuan Li
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205
| | - Minghui Lu
- Varex Imaging Corporation, 683 River Oaks Parkway, San Jose, CA 95134
| | - Jin Zhang
- Varex Imaging Corporation, 683 River Oaks Parkway, San Jose, CA 95134
| | - Josh Star-Lack
- Varex Imaging Corporation, 683 River Oaks Parkway, San Jose, CA 95134
| | - Richard E Colbeth
- Varex Imaging Corporation, 683 River Oaks Parkway, San Jose, CA 95134
| | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205
| | - J Webster Stayman
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205
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24
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Shi G, Subramanian S, Cao Q, Demehri S, Siewerdsen JH, Zbijewski W. Application of a Novel Ultra-High Resolution Multi-Detector CT in Quantitative Imaging of Trabecular Microstructure. Proc SPIE Int Soc Opt Eng 2020; 11317:113171E. [PMID: 33597792 PMCID: PMC7885907 DOI: 10.1117/12.2552385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
PURPOSE To evaluate the performance of a novel ultra-high resolution multi-detector CT scanner (Canon Aquilion Precision UHR CT), capable of visualizing ~150 μm details, in quantitative assessment of bone microarchitecture. Compared to conventional CT, the spatial resolution of UHR CT begins to approach the size of the trabeculae. This might enable measurements of microstructural correlates of osteoporosis, osteoarthritis, and other bone disease. METHODS The UHR CT system features a 160-row x-ray detector with 250×250 μm pixels (measured at isocenter) and a custom-designed x-ray source with a 0.4×0.5 mm focal spot. Visualization of high contrast details down to ~150 μm has been achieved on this device, which is now commercially available for clinical use. To evaluate the performance of UHR CT in quantification of bone microstructure, we imaged a variety of human bone samples (including ulna, radius, and vertebrae) embedded in a ~16 cm diameter plastic cylinder and in an anthropomorphic thorax phantom (QRM-Thorax, QRM Gmbh). Helical UHR CT acquisitions (120 kVp tube voltage) were acquired at scan exposures of 375 mAs - 5 mAs. For comparison, the samples were also imaged using a Normal Resolution (NR) mode available on the scanner, involving 500 μm slice thickness, exposure of 50 mAs, and a focal spot of 0.6×1.3 mm. We obtained micro-CT (μCT) of the bone samples at ~28 μm voxel size as a gold-standard reference. Geometric measurements of bone microstructure were performed in 17 regions-of-interests (ROIs) distributed throughout the bones of the phantoms; image registration was used to place the ROIs at corresponding locations in the UHR CT and NR CT. Trabecular thickness Tb.Th, spacing Tb.Sp, and Bone Volume fraction BvTv were obtained. The UHR and NR imaging protocols were compared terms of correlations to μCT and error of trabecular measurements. The effect of dose on trabecular morphometry was also studied for the UHR CT. Furthermore, we evaluated the sensitivity of texture features of trabecular bone (recently proposed as an alternative to geometric indices of microstructure) to imaging protocol. Image texture evaluation was performed using ~150 regions of interest (ROIs) across all bone samples. Three-dimensional Gray Level Co-occurrence Matrix (GLCM) and Gray Level Run Length Matrix (GLRM) features were extracted for each ROI. We analyzed correlation and concordance correlation coefficient (CCC) of the mean ROI values of texture features obtained using the UHR and NR modes. RESULTS UHR CT reconstructions of bone samples clearly demonstrated improved visualization of the trabeculae compared to NR CT. UHR CT achieved substantially better correlations for all three metrics of bone microstructure, in particular for BvTv (correlation coefficient of 0.91 for UHR CT compared to 0.84 for NR CT) and TbSp (correlation of 0.74 for UHR CT and 0.047 for NR CT). The error obtained with UHR CT was generally smaller than that of NR CT. For TbSp, the mean deviation from μCT (averaged across all bone samples) was only ~0.07 for UHR CT, compared to 0.25 for NR CT. Analysis of reproducibility of texture features of trabecular bone between UHR CT and NR CT revealed fair correlations (>0.7) for the majority of GLCM features, but relatively poor CCC (e.g. 0.02 for Energy and 0.04 for Entropy). The magnitude of texture metrics is particularly affected by the enhanced spatial resolution of UHR CT. CONCLUSION The recently introduced UHR CT achieves improved correlation and reduced error in measurements of trabecular bone microstructure compared to conventional resolution CT. Future development of diagnostic strategies based on textural biomarkers derived from UHR CT will need to account for potential sensitivity of texture features to image resolution.
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Affiliation(s)
- G Shi
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
| | - S Subramanian
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
| | - Q Cao
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
| | - S Demehri
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD USA 21287
| | - J H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
- Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD USA 21287
| | - W Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD USA 21205
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25
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Leung KM, Curran-Everett D, Regan EA, Lynch DA, Jacobson FL. Translation of adapting quantitative CT data from research to local clinical practice: validation evaluation of fully automated procedures to provide lung volumes and percent emphysema. J Med Imaging (Bellingham) 2019; 7:022404. [PMID: 31824985 DOI: 10.1117/1.jmi.7.2.022404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 11/20/2019] [Indexed: 11/14/2022] Open
Abstract
Current clinical chest CT reporting includes limited qualitative assessment of emphysema with rare mention of lung volumes and limited reporting of emphysema, based upon retrospective review of CT reports. Quantitative CT analysis performed in COPDGene and other research cohorts utilize semiautomated segmentation procedures and well-established research method (Thirona). We compared this reference QCT data with fully automated QCT analysis that can be obtained at the time of CT scan and sent to PACS along with standard chest CT images. 164 COPDGene® cohort study subjects enrolled at Brigham and Women's Hospital had baseline and 5-year follow-up CT scans. Subjects included 17 nonsmoking controls, 92 smokers with normal spirometry, 15 preserved ratio impaired spirometry (PRISm) patients, 12 GOLD 1, 20 GOLD 2, and 8 GOLD 3-4. 97% ( n = 319 ) of clinical reports did not mention lung volumes, and 14% ( n = 46 ) made no mention of emphysema. Total lung volumes determined by the fully automated algorithm were consistently 47 milliliters (ml) less than the Thirona reference value for all subjects (95% confidence interval - 62 to - 32 ml ). Percent emphysema values were equivalent to the Thirona reference values. Well-established research reference data can be used to evaluate and validate automated QCT software. Validation can be repeated as software is updated.
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Affiliation(s)
- Krystle M Leung
- Harvard University, Brigham Health, Department of Radiology, Boston, Massachusetts, United States
| | | | - Elizabeth A Regan
- National Jewish Health, Department of Radiology, Denver, Colorado, United States
| | - David A Lynch
- National Jewish Health, Department of Radiology, Denver, Colorado, United States
| | - Francine L Jacobson
- Harvard University, Brigham Health, Department of Radiology, Boston, Massachusetts, United States
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26
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Feldhaus FW, Theilig DC, Hubner RH, Kuhnigk JM, Neumann K, Doellinger F. Quantitative CT analysis in patients with pulmonary emphysema: is lung function influenced by concomitant unspecific pulmonary fibrosis? Int J Chron Obstruct Pulmon Dis 2019; 14:1583-1593. [PMID: 31409984 PMCID: PMC6646798 DOI: 10.2147/copd.s204007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 05/16/2019] [Indexed: 11/30/2022] Open
Abstract
Purpose Quantitative analysis of CT scans has proven to be a reproducible technique, which might help to understand the pathophysiology of chronic obstructive pulmonary disease (COPD) and combined pulmonary fibrosis and emphysema. The aim of this retrospective study was to find out if the lung function of patients with COPD with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages III or IV and pulmonary emphysema is measurably influenced by high attenuation areas as a correlate of concomitant unspecific fibrotic changes of lung parenchyma. Patients and methods Eighty-eight patients with COPD GOLD stage III or IV underwent CT and pulmonary function tests. Quantitative CT analysis was performed to determine low attenuation volume (LAV) and high attenuation volume (HAV), which are considered to be equivalents of fibrotic (HAV) and emphysematous (LAV) changes of lung parenchyma. Both parameters were determined for the whole lung, as well as peripheral and central lung areas only. Multivariate regression analysis was used to correlate HAV with different parameters of lung function. Results Unlike LAV, HAV did not show significant correlation with parameters of lung function. Even in patients with a relatively high HAV of more than 10%, in contrast to HAV (p=0.786) only LAV showed a significantly negative correlation with forced expiratory volume in 1 second (r=−0.309, R2=0.096, p=0.003). A severe decrease of DLCO% was associated with both larger HAV (p=0.045) and larger LAV (p=0.001). Residual volume and FVC were not influenced by LAV or HAV. Conclusion In patients with COPD GOLD stage III-IV, emphysematous changes of lung parenchyma seem to have such a strong influence on lung function, which is a possible effect of concomitant unspecific fibrosis is overwhelmed.
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Affiliation(s)
- Felix W Feldhaus
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Department of Radiology, Berlin, Germany
| | - Dorothea Cornelia Theilig
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Department of Radiology, Berlin, Germany
| | - Ralf-Harto Hubner
- Department of Internal Medicine/Infectious and Respiratory Disease, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Jan-Martin Kuhnigk
- Institute for Medical Image Computing, Fraunhofer MEVIS, Bremen, Germany
| | - Konrad Neumann
- Institute of Biometrics and Clinical Epidemiology, Charité Universitätsmedizin Berlin, Berlin, Gemany
| | - Felix Doellinger
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Department of Radiology, Berlin, Germany
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Sarioglu O, Gezer S, Sarioglu FC, Koremezli N, Kara T, Akcali O, Ozaksoy D, Balci A. Evaluation of vertebral bone mineral density in scoliosis by using quantitative computed tomography. Pol J Radiol 2019; 84:e131-5. [PMID: 31019606 DOI: 10.5114/pjr.2019.84060] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 02/14/2019] [Indexed: 02/06/2023] Open
Abstract
Purpose Scoliosis is described as a lateral curvature of the spine. We aimed to evaluate bone mineral density (BMD) in patients with scoliosis by using quantitative computed tomography (QCT) and compare the BMD of idiopathic and congenital scoliosis patients. Material and methods Forty-three patients aged 1 to 40 years with idiopathic, congenital, or neuromuscular scoliosis and 41 matched controls of the same sex and approximate age were included in the study. Measurements of BMD were performed by QCT analysis for each vertebral body from T12 to L5, and mean BMD was calculated for each case. Results Twenty-two of the patients with scoliosis were idiopathic, 15 were congenital, four were neuromuscular, and two were neurofibromatosis. The mean BMD values of patients with scoliosis were significantly lower compared with the control group (106.8 ± 33.4 mg/cm3 vs. 124.9 ± 29.1 mg/cm3, p = 0.009). No significant difference in BMD values was found between idiopathic and congenital scoliosis patients (p > 0.05). Conclusions This study illustrated that the vertebral body BMD values of the patients with scoliosis were significantly lower than those seen in the control group.
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Kumar I, Verma A, Jain A, Agarwal SK. Performance of quantitative CT parameters in assessment of disease severity in COPD: A prospective study. Indian J Radiol Imaging 2018; 28:99-106. [PMID: 29692536 PMCID: PMC5894329 DOI: 10.4103/ijri.ijri_296_17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Both emphysematous destruction of lung parenchyma and airway remodeling is thought to contribute to airflow limitation in cases of chronic obstructive pulmonary disease (COPD). OBJECTIVE To evaluate the value of quantitative computed tomography (QCT) parameters of emphysema and airway disease with disease severity in patients with COPD. MATERIALS AND METHODS We prospectively studied 50 patients with COPD, which included nonsmokers and patients with different degrees of cumulative smoking exposure. Three QCT parameters namely LAA% (low attenuation area percentage), WA% (Wall area percentage), and pi10 were calculated as per the standard technique. Forced expiratory volume in 1 s (FEV1), BODE score, and MMRC dyspnea scale were used as measures of disease severity. RESULTS FEV1 was inversely and significantly associated with all three QCT parameters. Receiver operated characteristic curves in prediction of GOLD class 3 COPD yielded cut-off values of 12.2, 61.45, and 3.5 for LAA%, WA%, and pi10, respectively, with high sensitivities and specificities. In multiple linear regression model, however, only LAA% proved to be significantly associated with FEV1, BODE, and dyspnea. CONCLUSION QCT indices of both emphysema and airway disease influence FEV1, dyspnea, and BODE score in patients with COPD. Emphysema, however, appears to be more closely related to disease severity.
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Affiliation(s)
- Ishan Kumar
- Department of Radiodiagnosis, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Ashish Verma
- Department of Radiodiagnosis, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Avinash Jain
- Department of TB and Respiratory Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - S. K. Agarwal
- Department of TB and Respiratory Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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Mussmann B, Overgaard S, Torfing T, Traise P, Gerke O, Andersen PE. Agreement and precision of periprosthetic bone density measurements in micro-CT, single and dual energy CT. J Orthop Res 2017; 35:1470-1477. [PMID: 27600874 DOI: 10.1002/jor.23417] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 09/06/2016] [Indexed: 02/04/2023]
Abstract
The objective of this study was to test the precision and agreement between bone mineral density measurements performed in micro CT, single and dual energy computed tomography, to determine how the keV level influences density measurements and to assess the usefulness of quantitative dual energy computed tomography as a research tool for longitudinal studies aiming to measure bone loss adjacent to total hip replacements. Samples from 10 fresh-frozen porcine femoral heads were placed in a Perspex phantom and computed tomography was performed with two acquisition modes. Bone mineral density was calculated and compared with measurements derived from micro CT. Repeated scans and dual measurements were performed in order to measure between- and within-scan precision. Mean density difference between micro CT and single energy computed tomography was 72 mg HA/cm3 . For dual energy CT, the mean difference at 100 keV was 128 mg HA/cm3 while the mean difference at 110-140 keV ranged from -84 to -67 mg HA/cm3 compared with micro CT. Rescanning the samples resulted in a non-significant overall between-scan difference of 13 mg HA/cm3 . Bland-Altman limits of agreement were wide and intraclass correlation coefficients ranged from 0.29 to 0.72, while 95% confidence intervals covered almost the full possible range. Repeating the density measurements for within-scan precision resulted in ICCs >0.99 and narrow limits of agreement. Single and dual energy quantitative CT showed excellent within-scan precision, but poor between-scan precision. No significant density differences were found in dual energy quantitative CT at keV-levels above 110 keV. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1470-1477, 2017.
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Affiliation(s)
- Bo Mussmann
- Department of Radiology, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Søren Overgaard
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Orthopedic Surgery and Traumatology, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense, Denmark
| | - Trine Torfing
- Department of Radiology, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Peter Traise
- Hunter New England Imaging, Armidale Hospital, Armidale, New South Wales, Australia
| | - Oke Gerke
- Department of Nuclear Medicine, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense, Denmark.,Centre of Health Economics Research, University of Southern Denmark, Odense, Denmark
| | - Poul Erik Andersen
- Department of Radiology, Odense University Hospital, Sdr. Boulevard 29, 5000, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
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Szczykutowicz TP, DuPlissis A, Pickhardt PJ. Variation in CT Number and Image Noise Uniformity According to Patient Positioning in MDCT. AJR Am J Roentgenol 2017; 208:1064-72. [PMID: 28267350 DOI: 10.2214/AJR.16.17215] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Many algorithms for clinical decision making rely on assessment of the CT number (expressed as Hounsfield units); however, to our knowledge, few, if any, studies have addressed how CT numbers change as a function of patient positioning within the scanner. MATERIALS AND METHODS An anthropomorphic phantom underwent imaging with varying amounts of vertical orientation misalignment with respect to isocenter. CT number and noise were measured using ROIs in the upper thorax, mid thorax, and abdomen. The degree of noise nonuniformity and changes in the CT number were assessed by comparing values obtained in the anterior versus posterior ROIs. To add clinical relevance, data on vertical mispositioning were collected from 20,316 clinical abdominal CT scans. Box-and-whisker plot analysis was used to identify the range of patient positioning. RESULTS Absolute CT number changes of more than 20 HU were observed for some ROIs at phantom positions of 10 cm from isocenter, with important differences noted between the thoracic and abdominal regions. Noise uniformity varied by more than twofold for all regions at 10 cm below isocenter. On clinical CT examinations, off-centering of more than 1, 2, 4, and 6 cm occurred for 41%, 19%, 1.9%, and 0.3% of patients, respectively. CONCLUSION Radiologists should treat CT number measurements with caution when patients are grossly mispositioned in the scanner. The substantial changes in attenuation values shown in the present study are large enough to warrant further investigation.
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Kizhakke Puliyakote AS, Vasilescu DM, Newell JD, Wang G, Weibel ER, Hoffman EA. Morphometric differences between central vs. surface acini in A/J mice using high-resolution micro-computed tomography. J Appl Physiol (1985) 2016; 121:115-22. [PMID: 27174924 DOI: 10.1152/japplphysiol.00317.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/06/2016] [Indexed: 11/22/2022] Open
Abstract
Through interior tomography, high-resolution microcomputed tomography (μCT) systems provide the ability to nondestructively assess the pulmonary acinus at micron and submicron resolutions. With the application of systematic uniform random sampling (SURS) principles applied to in situ fixed, intact, ex vivo lungs, we have sought to characterize morphometric differences in central vs. surface acini to better understand how well surface acini reflect global acinar geometry. Lungs from six mice (A/J strain, 15-20 wk of age) were perfusion fixed in situ and imaged using a multiresolution μCT system (Micro XCT 400, Zeiss). With the use of lower-resolution whole lung images, SURS methods were used for identification of central and surface foci for high-resolution imaging. Acinar morphometric metrics included diameters, lengths, and branching angles for each alveolar duct and total path lengths from entrance of the acinus to the terminal alveolar sacs. In addition, acinar volume, alveolar surface area, and surface area/volume ratios were assessed. A generation-based analysis demonstrated that central acini have significantly smaller branch diameters at each generation with no significant increase in branch lengths. In addition to larger-diameter alveolar ducts, surface acini had significantly increased numbers of branches and terminal alveolar sacs. The total path lengths from the acinar entrance to the terminal nodes were found to be higher in the case of surface acini. Volumes and surface areas of surface acini are greater than central acini, but there were no differences in surface/volume ratios. In conclusion, there are significant structural differences between surface and central acini in the A/J mouse.
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Affiliation(s)
- Abhilash S Kizhakke Puliyakote
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa
| | | | - John D Newell
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa
| | - Ge Wang
- Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; Department of Biomedical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | | | - Eric A Hoffman
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa; Department of Medicine, University of Iowa, Iowa City, Iowa;
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Xie M, Wang W, Dou S, Cui L, Xiao W. Quantitative computed tomography measurements of emphysema for diagnosing asthma-chronic obstructive pulmonary disease overlap syndrome. Int J Chron Obstruct Pulmon Dis 2016; 11:953-61. [PMID: 27226711 PMCID: PMC4866743 DOI: 10.2147/copd.s104484] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Background The diagnostic criteria of asthma–COPD overlap syndrome (ACOS) are controversial. Emphysema is characteristic of COPD and usually does not exist in typical asthma patients. Emphysema in patients with asthma suggests the coexistence of COPD. Quantitative computed tomography (CT) allows repeated evaluation of emphysema noninvasively. We investigated the value of quantitative CT measurements of emphysema in the diagnosis of ACOS. Methods This study included 404 participants; 151 asthma patients, 125 COPD patients, and 128 normal control subjects. All the participants underwent pulmonary function tests and a high-resolution CT scan. Emphysema measurements were taken with an Airway Inspector software. The asthma patients were divided into high and low emphysema index (EI) groups based on the percentage of low attenuation areas less than −950 Hounsfield units. The characteristics of asthma patients with high EI were compared with those having low EI or COPD. Results The normal value of percentage of low attenuation areas less than −950 Hounsfield units in Chinese aged >40 years was 2.79%±2.37%. COPD patients indicated more severe emphysema and more upper-zone-predominant distribution of emphysema than asthma patients or controls. Thirty-two (21.2%) of the 151 asthma patients had high EI. Compared with asthma patients with low EI, those with high EI were significantly older, more likely to be male, had more pack-years of smoking, had more upper-zone-predominant distribution of emphysema, and had greater airflow limitation. There were no significant differences in sex ratios, pack-years of smoking, airflow limitation, or emphysema distribution between asthma patients with high EI and COPD patients. A greater number of acute exacerbations were seen in asthma patients with high EI compared with those with low EI or COPD. Conclusion Asthma patients with high EI fulfill the features of ACOS, as described in the Global Initiative for Asthma and Global Initiative for Chronic Obstructive Lung Disease guidelines. Quantitative CT measurements of emphysema may help in diagnosing ACOS.
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Affiliation(s)
- Mengshuang Xie
- Department of Pulmonary Medicine, Qilu Hospital, Shandong University, Jinan, People's Republic of China
| | - Wei Wang
- Department of Pulmonary Medicine, Qilu Hospital, Shandong University, Jinan, People's Republic of China
| | - Shuang Dou
- Department of Pulmonary Medicine, Qilu Hospital, Shandong University, Jinan, People's Republic of China
| | - Liwei Cui
- Department of Pulmonary Medicine, Qilu Hospital, Shandong University, Jinan, People's Republic of China
| | - Wei Xiao
- Department of Pulmonary Medicine, Qilu Hospital, Shandong University, Jinan, People's Republic of China
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Kizhakke Puliyakote AS, Vasilescu DM, Sen Sharma K, Wang G, Hoffman EA. A skeleton-tree-based approach to acinar morphometric analysis using microcomputed tomography with comparison of acini in young and old C57BL/6 mice. J Appl Physiol (1985) 2016; 120:1402-9. [PMID: 26940656 DOI: 10.1152/japplphysiol.00923.2015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 02/29/2016] [Indexed: 11/22/2022] Open
Abstract
We seek to establish a method using interior tomographic techniques (Xradia MicroXCT-400) for acinar morphometric analysis using the pathway center lines from micro X-ray computed tomographic (Micro-CT) images as the road map. Through the application of these techniques, we present a method to extend the atlas of murine lungs to acinar levels and present a comparison between two age groups of the C57BL/6 strain. Lungs fixed via vascular perfusion were scanned using high-resolution Micro-CT protocols. Individual acini were segmented, and skeletonized paths to alveolar sacs from the entrance to the acinus were formed. Morphometric parameters, including branch lengths, diameters, and branching angles, were generated. Six mice each, at two age groups (∼20 and ∼90 wk of age), were studied. Additive Gaussian noise (0 mean and SD 1, 2, 5, and 10) was used to test the robustness of the analytical method. Noise-based variations were within ±6 μm for branch lengths and ±5 μm for diameters. At a noise level of 10, errors increased. Branch diameters were less susceptible to noise than lengths. There was >95% center line overlap across all noise levels. The measurements obtained using the center lines as a road map were not affected by added noise. Acini from younger mice had smaller branch diameters and lengths at all generations without significant differences in branching angles. The relative distribution of volume in the alveolar ducts was similar across both age groups. The method has been demonstrated to be repeatable and robust to image noise and provides a new, nondestructive technique to assess and compare acinar morphometry quantitatively.
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Affiliation(s)
- Abhilash S Kizhakke Puliyakote
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa
| | | | - Kriti Sen Sharma
- Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; and
| | - Ge Wang
- Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia; and Department of Biomedical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - Eric A Hoffman
- Department of Radiology, University of Iowa, Iowa City, Iowa; Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa; Department of Medicine, University of Iowa, Iowa City, Iowa;
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Hoffman EA, Lynch DA, Barr RG, van Beek EJR, Parraga G. Pulmonary CT and MRI phenotypes that help explain chronic pulmonary obstruction disease pathophysiology and outcomes. J Magn Reson Imaging 2016; 43:544-57. [PMID: 26199216 PMCID: PMC5207206 DOI: 10.1002/jmri.25010] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/01/2015] [Indexed: 12/12/2022] Open
Abstract
Pulmonary x-ray computed tomographic (CT) and magnetic resonance imaging (MRI) research and development has been motivated, in part, by the quest to subphenotype common chronic lung diseases such as chronic obstructive pulmonary disease (COPD). For thoracic CT and MRI, the main COPD research tools, disease biomarkers are being validated that go beyond anatomy and structure to include pulmonary functional measurements such as regional ventilation, perfusion, and inflammation. In addition, there has also been a drive to improve spatial and contrast resolution while at the same time reducing or eliminating radiation exposure. Therefore, this review focuses on our evolving understanding of patient-relevant and clinically important COPD endpoints and how current and emerging MRI and CT tools and measurements may be exploited for their identification, quantification, and utilization. Since reviews of the imaging physics of pulmonary CT and MRI and reviews of other COPD imaging methods were previously published and well-summarized, we focus on the current clinical challenges in COPD and the potential of newly emerging MR and CT imaging measurements to address them. Here we summarize MRI and CT imaging methods and their clinical translation for generating reproducible and sensitive measurements of COPD related to pulmonary ventilation and perfusion as well as parenchyma morphology. The key clinical problems in COPD provide an important framework in which pulmonary imaging needs to rapidly move in order to address the staggering burden, costs, as well as the mortality and morbidity associated with COPD.
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Affiliation(s)
- Eric A Hoffman
- Department of Radiology, University of Iowa, Iowa City, Iowa, USA
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
- Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa, USA
| | - David A Lynch
- Department of Radiology, National Jewish Health Center, Denver, Colorado, USA
| | - R Graham Barr
- Division of General Medicine, Division of Pulmonary, Allergy and Critical Care, Department of Medicine, Columbia University Medical Center, New York, New York, USA
- Department of Epidemiology, Columbia University Medical Center, New York, New York, USA
| | - Edwin J R van Beek
- Clinical Research Imaging Centre, Queen's Medical Research Institute, University of Edinburgh, Scotland, UK
| | - Grace Parraga
- Robarts Research Institute, University of Western Ontario, London, Canada
- Department of Medical Biophysics, University of Western Ontario, London, Canada
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Ziemlewicz TJ, Maciejewski A, Binkley N, Brett AD, Brown JK, Pickhardt PJ. Direct Comparison of Unenhanced and Contrast-Enhanced CT for Opportunistic Proximal Femur Bone Mineral Density Measurement: Implications for Osteoporosis Screening. AJR Am J Roentgenol 2016; 206:694-8. [PMID: 26866336 DOI: 10.2214/AJR.15.15128] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE For patients undergoing contrast-enhanced CT examinations that include the proximal femur, an opportunity exists for concurrent screening bone mineral density (BMD) measurement. We investigated the effect of IV contrast enhancement on CT-derived x-ray absorptiometry areal BMD measurement. MATERIALS AND METHODS Our cohort included 410 adults (mean age, 65.3 ± 10.0 years; range, 49-95 years) who underwent split-bolus CT urography at 120 kVp. Areal femoral neck BMD in g/cm(2) was measured on both unenhanced and contrast-enhanced CT series with asynchronous phantom calibration. Constant offset and multiplicative factor corrections for the contrast-enhanced series were derived from the Bland-Altman plot linear regression slopes. RESULTS Mean unenhanced and contrast-enhanced areal femoral neck BMD values were 0.681 ± 0.118 and 0.713 ± 0.123 g/cm(2), respectively. The SD of the distribution of residuals for the constant offset and multiplicative model corrections were 0.0232 and 0.0231, respectively. The constant offset correction associated with contrast enhancement was 0.032 ± 0.023 g/cm(2), which corresponds to 0.29 ± 0.21 T-score units using the CT-derived x-ray absorptiometry young normal areal femoral neck BMD reference SD of 0.111 g/cm(2). CONCLUSION For the purposes of opportunistic osteoporosis screening, contrast-enhanced abdominopelvic CT studies are equivalent to unenhanced CT and can therefore be used for femoral neck BMD assessment. This measure could greatly enhance osteoporosis screening.
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Boes JL, Bule M, Hoff BA, Chamberlain R, Lynch DA, Stojanovska J, Martinez FJ, Han MK, Kazerooni EA, Ross BD, Galbán CJ. The Impact of Sources of Variability on Parametric Response Mapping of Lung CT Scans. ACTA ACUST UNITED AC 2015; 1:69-77. [PMID: 26568983 PMCID: PMC4643661 DOI: 10.18383/j.tom.2015.00148] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Parametric response mapping (PRM) of inspiration and expiration computed tomography (CT) images improves the radiological phenotyping of chronic obstructive pulmonary disease (COPD). PRM classifies individual voxels of lung parenchyma as normal, emphysematous, or nonemphysematous air trapping. In this study, bias and noise characteristics of the PRM methodology to CT and clinical procedures were evaluated to determine best practices for this quantitative technique. Twenty patients of varying COPD status with paired volumetric inspiration and expiration CT scans of the lungs were identified from the baseline COPDGene cohort. The impact of CT scanner manufacturer and reconstruction kernels were evaluated as potential sources of variability in PRM measurements along with simulations to quantify the impact of inspiration/expiration lung volume levels, misregistration, and image spacing on PRM measurements. Negligible variation in PRM metrics was observed when CT scanner type and reconstruction were consistent and inspiration/expiration lung volume levels were near target volumes. CT scanner Hounsfield unit drift occurred but remained difficult to ameliorate. Increasing levels of image misregistration and CT slice spacing were found to have a minor effect on PRM measurements. PRM-derived values were found to be most sensitive to lung volume levels and mismatched reconstruction kernels. As with other quantitative imaging techniques, reliable PRM measurements are attainable when consistent clinical and CT protocols are implemented.
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Affiliation(s)
- Jennifer L Boes
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | - Maria Bule
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | - Benjamin A Hoff
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | | | | | - Jadranka Stojanovska
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | | | - Meilan K Han
- Department of Internal Medicine, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | - Ella A Kazerooni
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | - Brian D Ross
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
| | - Craig J Galbán
- Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, MI
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Mobberley SD, Fuld MK, Sieren JP, Primak AN, Hoffman EA. Scatter correction associated with dedicated dual-source CT hardware improves accuracy of lung air measures. Acad Radiol 2013; 20:1334-43. [PMID: 24119345 DOI: 10.1016/j.acra.2013.04.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 04/09/2013] [Accepted: 04/09/2013] [Indexed: 11/17/2022]
Abstract
RATIONALE AND OBJECTIVES Accurate assessment of air density used to quantitatively characterize amount and distribution of emphysema in chronic obstructive pulmonary disease (COPD) subjects has remained challenging. Hounsfield units (HU) within tracheal air can be considerably less negative than -1000 HU. This study has sought to characterize the effects of improved scatter correction used in dual-source pulmonary computed tomography (CT). MATERIALS AND METHODS Dual-source dual-energy (DSDE) and single-source (SS) scans taken at multiple energy levels and scan settings were acquired for quantitative comparison using anesthetized ovine (n = 6), swine (n = 13), and a lung phantom. Data were evaluated for the lung, inferior vena cava, and tracheal segments. To minimize the effect of cross-scatter, the phantom scans in the DSDE mode were obtained by reducing the current of one of the tubes to near zero. RESULTS A significant shift in mean HU values in the tracheal regions of animals and the phantom is observed, with values consistently closer to -1000 HU in DSDE mode. HU values associated with SS mode demonstrated a positive shift of up to 32 HU. In vivo tracheal air measurements demonstrated considerable variability with SS scanning, whereas these values were more consistent with DSDE imaging. Scatter effects in the lung parenchyma differed from adjacent tracheal measures. CONCLUSION Data suggest that the scatter correction introduced into the dual-energy mode of imaging has served to provide more accurate CT lung density measures sought to quantitatively assess the presence and distribution of emphysema in COPD subjects. Data further suggest that CT images, acquired without adequate scatter correction, cannot be corrected by linear algorithms given the variability in tracheal air HU values and the independent scatter effects on lung parenchyma.
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Affiliation(s)
- Sean D Mobberley
- Department of Radiology, Division of Physiological Imaging, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, CC 701 GH, University of Iowa Carver College of Medicine, Iowa City, IA 52241; Department of Biomedical Engineering, University of Iowa, Iowa City, IA
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