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13. Protocols for multi-site trials using hyperpolarized 129Xe MRI for imaging of ventilation, alveolar-airspace size, and gas exchange: A position paper from the 129Xe MRI clinical trials consortium

Author

Niedbalski, P.J., Hall, C.S., Castro, M., Eddy, R.L., Rayment, J.H., Svenningsen, S., Parraga, G., Zanette, B., Santyr, G.E., Thomen, R.P., Stewart, N.J., Collier, G.J., Chan, H., Wild, J.M., Fain, S.B., Miller, G.W., Mata, J.F., Mugler, J.P., Driehuys, B., Willmering, M.M., Cleveland, Z.I., and Woods, J.C.

Abstract

Hyperpolarized (HP) 129Xe MRI uniquely images pulmonary ventilation, gas exchange, and terminal airway morphology rapidly and safely, providing novel information not possible using conventional imaging modalities or pulmonary function tests. As such, there is mounting interest in expanding the use of biomarkers derived from HP 129Xe MRI as outcome measures in multi-site clinical trials across a range of pulmonary disorders. Until recently, HP 129Xe MRI techniques have been developed largely independently at a limited number of academic centers, without harmonizing acquisition strategies. To promote uniformity and adoption of HP 129Xe MRI more widely in translational research, multi-site trials, and ultimately clinical practice, this position paper from the 129Xe MRI Clinical Trials Consortium (https://cpir.cchmc.org/XeMRICTC) recommends standard protocols to harmonize methods for image acquisition in HP 129Xe MRI. Recommendations are described for the most common HP gas MRI techniques—calibration, ventilation, alveolar-airspace size, and gas exchange—across MRI scanner manufacturers most used for this application. Moreover, recommendations are described for 129Xe dose volumes and breath-hold standardization to further foster consistency of imaging studies. The intention is that sites with HP 129Xe MRI capabilities can readily implement these methods to obtain consistent high-quality images that provide regional insight into lung structure and function. While this document represents consensus at a snapshot in time, a roadmap for technical developments is provided that will further increase image quality and efficiency. These standardized dosing and imaging protocols will facilitate the wider adoption of HP 129Xe MRI for multi-site pulmonary research.

Published
2021

30. Correction: Predictive value for cardiovascular events of common carotid intima media thickness and its rate of change in individuals at high cardiovascular risk - Results from the PROG-IMT collaboration (PLoS One (2018) 13:4 (e0191172) DOI: 10.1371/journal.pone.0191172)

Author

Lorenz M. W., Gao L., Ziegelbauer K., Norata G. D., Empana J. P., Schmidtmann I., Lin H. -J., McLachlan S., Bokemark L., Ronkainen K., Amato M., Schminke U., Srinivasan S. R., Lind L., Okazaki S., Stehouwer C. D. A., Willeit P., Polak J. F., Steinmetz H., Sander D., Poppert H., Desvarieux M., Arfan Ikram M., Johnsen S. H., Staub D., Sirtori C. R., Iglseder B., Beloqui O., Engstrom G., Friera A., Rozza F., Xie W., Parraga G., Grigore L., Plichart M., Blankenberg S., Su T. -C., Schmidt C., Tuomainen T. -P., Veglia F., Volzke H., Nijpels G., Willeit J., Sacco R. L., Franco O. H., Uthoff H., Hedblad B., Suarez C., Izzo R., Zhao D., Wannarong T., Catapano A., Ducimetiere P., Espinola-Klein C., Chien K. -L., Price J. F., Bergstrom G., Kauhanen J., Tremoli E., Dorr M., Berenson G., Kitagawa K., Dekker J. M., Kiechl S., Sitzer M., Bickel H., Rundek T., Hofman A., Mathiesen E. B., Castelnuovo S., Landecho M. F., Rosvall M., Gabriel R., De Luca N., Liu J., Baldassarre D., Kavousi M., De Groot E., Bots M. L., Yanez D. N., Thompson S. G., Lorenz, M. W., Gao, L., Ziegelbauer, K., Norata, G. D., Empana, J. P., Schmidtmann, I., Lin, H. -J., Mclachlan, S., Bokemark, L., Ronkainen, K., Amato, M., Schminke, U., Srinivasan, S. R., Lind, L., Okazaki, S., Stehouwer, C. D. A., Willeit, P., Polak, J. F., Steinmetz, H., Sander, D., Poppert, H., Desvarieux, M., Arfan Ikram, M., Johnsen, S. H., Staub, D., Sirtori, C. R., Iglseder, B., Beloqui, O., Engstrom, G., Friera, A., Rozza, F., Xie, W., Parraga, G., Grigore, L., Plichart, M., Blankenberg, S., Su, T. -C., Schmidt, C., Tuomainen, T. -P., Veglia, F., Volzke, H., Nijpels, G., Willeit, J., Sacco, R. L., Franco, O. H., Uthoff, H., Hedblad, B., Suarez, C., Izzo, R., Zhao, D., Wannarong, T., Catapano, A., Ducimetiere, P., Espinola-Klein, C., Chien, K. -L., Price, J. F., Bergstrom, G., Kauhanen, J., Tremoli, E., Dorr, M., Berenson, G., Kitagawa, K., Dekker, J. M., Kiechl, S., Sitzer, M., Bickel, H., Rundek, T., Hofman, A., Mathiesen, E. B., Castelnuovo, S., Landecho, M. F., Rosvall, M., Gabriel, R., De Luca, N., Liu, J., Baldassarre, D., Kavousi, M., De Groot, E., Bots, M. L., Yanez, D. N., and Thompson, S. G.

Abstract

An affiliation for Moise Desvarieux is missing. In addition to affiliation #22, Moise Desvarieux is affiliated with: METHODS Core, Centre de Recherche Epidémiologie et Statistique Paris Sorbonne Cité (CRESS), Institut National de la Santé et de la Recherche Médicale (INSERM) UMR 1153, Paris France.

Published
2018

41. Predictive value for cardiovascular events of common carotid intima media thickness and its rate of change in individuals at high cardiovascular risk - Results from the PROG-IMT collaboration

Author

Lorenz, MW, Gao, L, Ziegelbauer, K, Norata, GD, Empana, JP, Schmidtmann, I, Lin, H J, McLachlan, S, Bokemark, L, Ronkainen, K, Amato, M, Schminke, U, Srinivasan, SR (Sathanur), Lind, L, Okazaki, S, Stehouwer, CDA, Willeit, P, Polak, JF, Steinmetz, H, Sander, D, Poppert, H, Desvarieux, M, Ikram, Arfan, Johnsen, SH, Staub, D, Sirtori, CR, Igiseder, B, Beloqui, O, Engstrom, G, Friera, A, Rozza, F, Xie, WX, Parraga, G, Grigore, L, Plichart, M, Blankenberg, S, Su, T C, Schmidt, C, Tuomainen, TP, Veglia, F, Volzke, H, Nijpels, G, Willeit, J, Sacco, RL, Franco Duran, OH, Uthoff, H, Hedblad, B, Suarez, C, Izzo, R, Zhao, D (Dan), Wannarong, T, Catapano, A, Ducimetiere, P, Espinola-Klein, C, Chien, K L, Price, JF, Bergstrom, G, Kauhanen, J, Tremoli, E, Dorr, M, Berenson, G, Kitagawa, K, Dekker, JM, Kiechl, S, Sitzer, M, Bickel, H, Rundek, T, Hofman, Bert, Mathiesen, EB, Castelnuovo, S, Landecho, MF, Rosvall, M, Gabriel, R, Luca, N, Liu, J, Baldassarre, D, Kavousi, Maryam, de Groot, E, Bots, ML, Yanez, D N, Lorenz, MW, Gao, L, Ziegelbauer, K, Norata, GD, Empana, JP, Schmidtmann, I, Lin, H J, McLachlan, S, Bokemark, L, Ronkainen, K, Amato, M, Schminke, U, Srinivasan, SR (Sathanur), Lind, L, Okazaki, S, Stehouwer, CDA, Willeit, P, Polak, JF, Steinmetz, H, Sander, D, Poppert, H, Desvarieux, M, Ikram, Arfan, Johnsen, SH, Staub, D, Sirtori, CR, Igiseder, B, Beloqui, O, Engstrom, G, Friera, A, Rozza, F, Xie, WX, Parraga, G, Grigore, L, Plichart, M, Blankenberg, S, Su, T C, Schmidt, C, Tuomainen, TP, Veglia, F, Volzke, H, Nijpels, G, Willeit, J, Sacco, RL, Franco Duran, OH, Uthoff, H, Hedblad, B, Suarez, C, Izzo, R, Zhao, D (Dan), Wannarong, T, Catapano, A, Ducimetiere, P, Espinola-Klein, C, Chien, K L, Price, JF, Bergstrom, G, Kauhanen, J, Tremoli, E, Dorr, M, Berenson, G, Kitagawa, K, Dekker, JM, Kiechl, S, Sitzer, M, Bickel, H, Rundek, T, Hofman, Bert, Mathiesen, EB, Castelnuovo, S, Landecho, MF, Rosvall, M, Gabriel, R, Luca, N, Liu, J, Baldassarre, D, Kavousi, Maryam, de Groot, E, Bots, ML, and Yanez, D N

Published
2018

42. Predictive value for cardiovascular events of common carotid intima media thickness and its rate of change in individuals at high cardiovascular risk – Results from the PROG-IMT collaboration

Author

Lorenz, M., Gao, L., Ziegelbauer, K., Norata, Giuseppe, Empana, J., Schmidtmann, I., Lin, H., McLachlan, S., Bokemark, L., Ronkainen, K., Amato, M., Schminke, U., Srinivasan, S., Lind, L., Okazaki, S., Stehouwer, C., Willeit, P., Polak, J., Steinmetz, H., Sander, D., Poppert, H., Desvarieux, M., Arfan Ikram, M., Johnsen, S., Staub, D., Sirtori, C., Iglseder, B., Beloqui, O., Engström, G., Friera, A., Rozza, F., Xie, W., Parraga, G., Grigore, L., Plichart, M., Blankenberg, S., Su, T., Schmidt, C., Tuomainen, T., Veglia, F., Völzke, H., Nijpels, G., Willeit, J., Sacco, R., Franco, O., Uthoff, H., Hedblad, B., Suarez, C., Izzo, R., Zhao, D., Wannarong, T., Catapano, A., Ducimetiere, P., Espinola-Klein, C., Chien, K., Price, J., Bergström, G., Kauhanen, J., Tremoli, E., Dörr, M., Berenson, G., Kitagawa, K., Dekker, J., Kiechl, S., Sitzer, M., Bickel, H., Rundek, T., Hofman, A., Mathiesen, E., Castelnuovo, S., Landecho, M., Rosvall, M., Gabriel, R., de Luca, N., Liu, J., Baldassarre, D., Kavousi, M., de Groot, E., Bots, M., Yanez, D., Thompson, S., Lorenz, M., Gao, L., Ziegelbauer, K., Norata, Giuseppe, Empana, J., Schmidtmann, I., Lin, H., McLachlan, S., Bokemark, L., Ronkainen, K., Amato, M., Schminke, U., Srinivasan, S., Lind, L., Okazaki, S., Stehouwer, C., Willeit, P., Polak, J., Steinmetz, H., Sander, D., Poppert, H., Desvarieux, M., Arfan Ikram, M., Johnsen, S., Staub, D., Sirtori, C., Iglseder, B., Beloqui, O., Engström, G., Friera, A., Rozza, F., Xie, W., Parraga, G., Grigore, L., Plichart, M., Blankenberg, S., Su, T., Schmidt, C., Tuomainen, T., Veglia, F., Völzke, H., Nijpels, G., Willeit, J., Sacco, R., Franco, O., Uthoff, H., Hedblad, B., Suarez, C., Izzo, R., Zhao, D., Wannarong, T., Catapano, A., Ducimetiere, P., Espinola-Klein, C., Chien, K., Price, J., Bergström, G., Kauhanen, J., Tremoli, E., Dörr, M., Berenson, G., Kitagawa, K., Dekker, J., Kiechl, S., Sitzer, M., Bickel, H., Rundek, T., Hofman, A., Mathiesen, E., Castelnuovo, S., Landecho, M., Rosvall, M., Gabriel, R., de Luca, N., Liu, J., Baldassarre, D., Kavousi, M., de Groot, E., Bots, M., Yanez, D., and Thompson, S.

Abstract

Aims: Carotid intima media thickness (CIMT) predicts cardiovascular (CVD) events, but the predictive value of CIMT change is debated. We assessed the relation between CIMT change and events in individuals at high cardiovascular risk. Methods and results: From 31 cohorts with two CIMT scans (total n = 89070) on average 3.6 years apart and clinical follow-up, subcohorts were drawn: (A) individuals with at least 3 cardiovascular risk factors without previous CVD events, (B) individuals with carotid plaques without previous CVD events, and (C) individuals with previous CVD events. Cox regression models were fit to estimate the hazard ratio (HR) of the combined endpoint (myocardial infarction, stroke or vascular death) per standard deviation (SD) of CIMT change, adjusted for CVD risk factors. These HRs were pooled across studies. In groups A, B and C we observed 3483, 2845 and 1165 endpoint events, respectively. Average common CIMT was 0.79mm (SD 0.16mm), and annual common CIMT change was 0.01mm (SD 0.07mm), both in group A. The pooled HR per SD of annual common CIMT change (0.02 to 0.43mm) was 0.99 (95% confidence interval: 0.95–1.02) in group A, 0.98 (0.93–1.04) in group B, and 0.95 (0.89–1.04) in group C. The HR per SD of common CIMT (average of the first and the second CIMT scan, 0.09 to 0.75mm) was 1.15 (1.07–1.23) in group A, 1.13 (1.05–1.22) in group B, and 1.12 (1.05–1.20) in group C. Conclusions: We confirm that common CIMT is associated with future CVD events in individuals at high risk. CIMT change does not relate to future event risk in high-risk individuals.

Published
2018

45. Anatomical pulmonary magnetic resonance imaging segmentation for regional structure-function measurements of asthma

Author

Guo, F, Svenningsen, S, Eddy, R L, Capaldi, D P I, Sheikh, K, Fenster, A, and Parraga, G

Subjects
convex optimization, volume proportion prior, multiregion segmentation, Medical Biophysics, 1H MRI
Abstract

PURPOSE: Pulmonary magnetic-resonance-imaging (MRI) and x-ray computed-tomography have provided strong evidence of spatially and temporally persistent lung structure-function abnormalities in asthmatics. This has generated a shift in their understanding of lung disease and supports the use of imaging biomarkers as intermediate endpoints of asthma severity and control. In particular, pulmonary (1)H MRI can be used to provide quantitative lung structure-function measurements longitudinally and in response to treatment. However, to translate such biomarkers of asthma, robust methods are required to segment the lung from pulmonary (1)H MRI. Therefore, their objective was to develop a pulmonary (1)H MRI segmentation algorithm to provide regional measurements with the precision and speed required to support clinical studies. METHODS: The authors developed a method to segment the left and right lung from (1)H MRI acquired in 20 asthmatics including five well-controlled and 15 severe poorly controlled participants who provided written informed consent to a study protocol approved by Health Canada. Same-day spirometry and plethysmography measurements of lung function and volume were acquired as well as (1)H MRI using a whole-body radiofrequency coil and fast spoiled gradient-recalled echo sequence at a fixed lung volume (functional residual capacity + 1 l). We incorporated the left-to-right lung volume proportion prior based on the Potts model and derived a volume-proportion preserved Potts model, which was approximated through convex relaxation and further represented by a dual volume-proportion preserved max-flow model. The max-flow model led to a linear problem with convex and linear equality constraints that implicitly encoded the proportion prior. To implement the algorithm, (1)H MRI was resampled into ∼3 × 3 × 3 mm(3) isotropic voxel space. Two observers placed seeds on each lung and on the background of 20 pulmonary (1)H MR images in a randomized dataset, on five occasions, five consecutive days in a row. Segmentation accuracy was evaluated using the Dice-similarity-coefficient (DSC) of the segmented thoracic cavity with comparison to five-rounds of manual segmentation by an expert observer. The authors also evaluated the root-mean-squared-error (RMSE) of the Euclidean distance between lung surfaces, the absolute, and percent volume error. Reproducibility was measured using the coefficient of variation (CoV) and intraclass correlation coefficient (ICC) for two observers who repeated segmentation measurements five-times. RESULTS: For five well-controlled asthmatics, forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) was 83% ± 7% and FEV1 was 86 ± 9%pred. For 15 severe, poorly controlled asthmatics, FEV1/FV C = 66% ± 17% and FEV1 = 72 ± 27%pred. The DSC for algorithm and manual segmentation was 91% ± 3%, 92% ± 2% and 91% ± 2% for the left, right, and whole lung, respectively. RMSE was 4.0 ± 1.0 mm for each of the left, right, and whole lung. The absolute (percent) volume errors were 0.1 l (∼6%) for each of right and left lung and ∼0.2 l (∼6%) for whole lung. Intra- and inter-CoV (ICC) were0.91%) for DSC and0.93%) for RMSE. While segmentation required 10 s including ∼6 s for user interaction, the smallest detectable difference was 0.24 l for algorithm measurements which was similar to manual measurements. CONCLUSIONS: This lung segmentation approach provided the necessary and sufficient precision and accuracy required for research and clinical studies.

Published
2016

46. Pulmonary hyperpolarized (129) Xe morphometry for mapping xenon gas concentrations and alveolar oxygen partial pressure: Proof-of-concept demonstration in healthy and COPD subjects

Author

Ouriadov, A, Farag, A, Kirby, M, McCormack, D G, Parraga, G, and Santyr, G E

Subjects
diffusion, hyperpolarized, lung, Aged, 80 and over, Male, Xenon, Contrast Media, Reproducibility of Results, Middle Aged, morphometry, pAO2, xenon concentration, Sensitivity and Specificity, respiratory tract diseases, Molecular Imaging, Oxygen, Pulmonary Alveoli, Pulmonary Disease, Chronic Obstructive, Diffusion Magnetic Resonance Imaging, Image Interpretation, Computer-Assisted, Medical Biophysics, Humans, Xenon Isotopes, Female, Tissue Distribution, Radiopharmaceuticals, Aged
Abstract

PURPOSE: Diffusion-weighted (DW) hyperpolarized (129) Xe morphometry magnetic resonance imaging (MRI) can be used to map regional differences in lung tissue micro-structure. We aimed to generate absolute xenon concentration ([Xe]) and alveolar oxygen partial pressure (pA O2 ) maps by extracting the unrestricted diffusion coefficient (D0 ) of xenon as a morphometric parameter. METHODS: In this proof-of-concept demonstration, morphometry was performed using multi b-value (0, 12, 20, 30 s/cm(2) ) DW hyperpolarized (129) Xe images obtained in four never-smokers and four COPD ex-smokers. Morphometric parameters and D0 maps were computed and the latter used to generate [Xe] and pA O2 maps. Xenon concentration phantoms estimating a range of values mimicking those observed in vivo were also investigated. RESULTS: Xenon D0 was significantly increased (P = 0.035) in COPD (0.14 ± 0.03 cm(2) /s) compared with never-smokers (0.12 ± 0.02 cm(2) /s). COPD ex-smokers also had significantly decreased [Xe] (COPD = 8 ± 7% versus never-smokers = 13 ± 8%, P = 0.012) and increased pA O2 (COPD = 18 ± 3% versus never-smokers = 15 ± 3%, P = 0.009) compared with never-smokers. Phantom measurements showed the expected dependence of D0 on [Xe] over the range of concentrations anticipated in vivo. CONCLUSION: DW hyperpolarized (129) Xe MRI morphometry can be used to simultaneously map [Xe] and pA O2 in addition to providing micro-structural biomarkers of emphysematous destruction in COPD. Phantom measurements of D0 ([Xe]) supported the hypotheses that differences in subjects may reflect differences in functional residual capacity.

Published
2015

47. Outcomes for Cervical Mediastinoscopy in a Community Teaching Hospital

Author

Dahele, M., Ung, Y., Bezjak, A., Burkes, R., Ellis, P., Behzadi, A., Solow, H., Laffan, S., Korec, M., Pearson, S., Purdie, T., Bissonnette, J.P., Brade, A., Cho, J.B.C., Sun, A., Hope, A., Franks, K., Jaffray, D.A., Lee, J., Correia, J.D., Walele, A.A., Ashrafi, A.S., Sturdza, A., Payne, D., Kane, G., Hodgson, D., Waldron, J., Catapano, J., Shepherd, F.A., Keshavjee, S., Anraku, M., Yun, Z., Zhang, L., Johnston, M.R., de Perrot, M., Louie, A., Rodrigues, G., Whiston, F., Stitt, L., Mathew, L., Parraga, G., Para, A.E., Calveley, V.L., Yeung, I.W.T., Van Dyk, J., Hill, R.P., Pan, L., Cohen, J., Okawara, G., Nair, P., Soliman, H., Cheung, P., Poon, I., Balogh, J., Barbera, L., Spayne, J., Danjoux, C., Lim, G., Higgins, J., Moseley, D., Hope, D., Cho, J., and Le, L.

Subjects
Ontario, Abstracts, lung cancer, Meeting Report and Abstracts, Thoracic cancer, conference
Published
2008

48. Functional Lung Avoidance for Individualized Radiation Therapy (FLAIR): Results of a Randomized, Double-Blind Clinical Trial

Author

Yaremko, B., primary, Hoover, D., additional, Capaldi, D., additional, Sheikh, K., additional, Dar, A.R., additional, Yu, E., additional, Rodrigues, G., additional, Louie, A.V., additional, Gaede, S., additional, Chen, J., additional, Erickson, A., additional, Warner, A., additional, Dingle, B., additional, Landis, M., additional, Sanatani, M., additional, Vincent, M., additional, Younus, J., additional, Kuruvilla, S., additional, Palma, D.A., additional, and Parraga, G., additional

Published
2017
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