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Lessard E, Young HM, Bhalla A, Pike D, Sheikh K, McCormack DG, Ouriadov A, Parraga G. Pulmonary 3He Magnetic Resonance Imaging Biomarkers of Regional Airspace Enlargement in Alpha-1 Antitrypsin Deficiency. Acad Radiol 2017. [PMID: 28645458 DOI: 10.1016/j.acra.2017.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
RATIONALE AND OBJECTIVES Thoracic x-ray computed tomography (CT) and hyperpolarized 3He magnetic resonance imaging (MRI) provide quantitative measurements of airspace enlargement in patients with emphysema. For patients with panlobular emphysema due to alpha-1 antitrypsin deficiency (AATD), sensitive biomarkers of disease progression and response to therapy have been difficult to develop and exploit, especially those biomarkers that correlate with outcomes like quality of life. Here, our objective was to generate and compare CT and diffusion-weighted inhaled-gas MRI measurements of emphysema including apparent diffusion coefficient (ADC) and MRI-derived mean linear intercept (Lm) in patients with AATD, chronic obstructive pulmonary disease (COPD) ex-smokers, and elderly never-smokers. MATERIALS AND METHODS We enrolled patients with AATD (n = 8; 57 ± 7 years), ex-smokers with COPD (n = 8; 77 ± 6 years), and a control group of never-smokers (n = 5; 64 ± 2 years) who underwent thoracic CT, MRI, spirometry, plethysmography, the St. George's Respiratory Questionnaire, and the 6-minute walk test during a single 2-hour visit. MRI-derived ADC, Lm, surface-to-volume ratio, and ventilation defect percent were generated for the apical, basal, and whole lung as was CT lung area ≤-950 Hounsfield units (RA950), low attenuating clusters, and airway count. RESULTS In patients with AATD, there was a significantly different MRI-derived ADC (P = .03), Lm (P < .0001), and surface-to-volume ratio (P < .0001), but not diffusing capacity of carbon monoxide, residual volume or total lung capacity, or CT RA950 (P > .05) compared to COPD ex-smokers with a significantly different St. George's Respiratory Questionnaire. CONCLUSIONS In this proof-of-concept demonstration, we evaluated CT and MRI lung emphysema measurements and observed significantly worse MRI biomarkers of emphysema in patients with AATD compared to patients with COPD, although CT RA950 and diffusing capacity of carbon monoxide were not significantly different, underscoring the sensitivity of MRI measurements of AATD emphysema.
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Affiliation(s)
- Eric Lessard
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, ON, Canada N6A 5C1
| | - Heather M Young
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, ON, Canada N6A 5C1
| | - Anurag Bhalla
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7
| | - Damien Pike
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, ON, Canada N6A 5C1
| | - Khadija Sheikh
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, ON, Canada N6A 5C1
| | - David G McCormack
- Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada
| | - Alexei Ouriadov
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, ON, Canada N6A 5C1
| | - Grace Parraga
- Robarts Research Institute, 1151 Richmond Street North, London, ON, Canada N6A 5B7; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, ON, Canada N6A 5C1.
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Ouriadov A, Lessard E, Sheikh K, Parraga G. Pulmonary MRI morphometry modeling of airspace enlargement in chronic obstructive pulmonary disease and alpha-1 antitrypsin deficiency. Magn Reson Med 2017; 79:439-448. [PMID: 28198571 DOI: 10.1002/mrm.26642] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 12/23/2022]
Abstract
PURPOSE We generated lung morphometry measurements using single-breath diffusion-weighted MRI and three different acinar duct models in healthy participants and patients with emphysema stemming from chronic obstructive lung disease (COPD) and alpha-1 antitrypsin deficiency (AATD). METHODS Single-breath-inhaled 3 He MRI with five diffusion sensitizations (b-value = 0, 1.6, 3.2, 4.8, and 6.4 s/cm2 ) was used, and signal intensities were fit using a cylindrical and single-compartment acinar-duct model to estimate MRI-derived mean linear intercept (Lm ) and surface-to-volume ratio (S/V). A stretched exponential model was also developed to estimate the mean airway length and Lm . RESULTS We evaluated 42 participants, including 15 elderly never-smokers (69 ± 5 years), 12 ex-smokers without COPD (67 ± 11 years), 9 COPD ex-smokers (80 ± 6 years), and 6 AATD patients (59 ± 6 years). In the never- and ex-smokers, the diffusing capacity of the lung for carbon monoxide (DLCO ) and computed tomography relative area of less than -950 Hounsfield units (RA950 ) were normal, but these were abnormal in the COPD and AATD patients, which is reflective of emphysema. Although cylindrical and stretched-exponential-model estimates of Lm and S/V were not significantly different, the single-compartment-model estimates were significantly different (P < 0.05) for the never- and ex-smoker subgroups. All models estimated significantly worse Lm and S/V in the AATD and COPD subgroups compared with the never- and ex-smokers without emphysema. CONCLUSIONS Differences in airspace enlargement may be estimated using Lm and S/V, generated using MRI and a stretched-exponential or cylindrical model of the acinar ducts. Magn Reson Med 79:439-448, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Alexei Ouriadov
- Robarts Research Institute, London, Canada.,Department of Medical Biophysics, the University of Western Ontario, London, Canada
| | - Eric Lessard
- Robarts Research Institute, London, Canada.,Department of Medical Biophysics, the University of Western Ontario, London, Canada
| | - Khadija Sheikh
- Robarts Research Institute, London, Canada.,Department of Medical Biophysics, the University of Western Ontario, London, Canada
| | - Grace Parraga
- Robarts Research Institute, London, Canada.,Department of Medical Biophysics, the University of Western Ontario, London, Canada
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Fiore RD, Drago-Ferrante R, D’Anneo A, Blasio AD, Santulli A, Messina C, Carlisi D, Tesoriere G, Vento R. Differentiation of human osteosarcoma 3AB-OS stem-like cells in derivatives of the three primary germ layers as a useful <i>in vitro</i> model to develop several purposes. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/scd.2013.33024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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