Katja Hueper^1,2, Jens Vogel-Claussen^1,2, Megha Parikh³, John HM Austin³, David A Bluemke⁴, James Carr⁵, Thomas A Goldstein⁶, Antoinette S Gomes⁷, Eric A Hoffman⁸, Joao AC Lima¹, Wendy Post¹, Martin Prince³, Kiang Liu⁵, Jan Skrok¹, Karol Watson⁷, Jie Zheng⁹, and Graham Barr^3
1Johns Hopkins University, Baltimore, Maryland, United States, ²Hannover Medical School, Hannover, Germany, ³Columbia University Medical Center, New York, New York, United States, ⁴Radiology and Imaging Sciences, National Institutes of Health, Bethesda, Maryland, United States, ⁵Northwestern University, Chicago, Illinois, United States, ⁶Stanford University, Stanford, California, United States, ⁷David Geffen UCLA School of Medicine, Los Angeles, California, United States, ⁸University of Iowa Carver College of Medicine, Iowa City, Iowa, United States, ⁹Washington University School of Medicine, St Louis, Missouri, United States

Pulmonary vascular changes are known to occur in very severe chronic obstructive pulmonary disease (COPD). We hypothesized that pulmonary parenchymal blood flow and volume were decreased in mild-moderate COPD. Using pulmonary perfusion MRI we quantified perfusion parameters on a pixel-by-pixel basis in 100 patients with different severities of COPD and controls. Pulmonary parenchymal blood flow and volume were decreased in mild, moderate and severe COPD after adjustment for multiple parameters including the stroke volume, smoking status and packyears. These results support our hypothesis and demonstrate the value of pulmonary perfusion MRI for direct assessment of pulmonary vasculature in COPD.

Grzegorz Bauman¹, Tobias Heimann², Eva Fritzsching³, Wolfhard Semmler¹, Michael Puderbach^4,5, and Monika Eichinger^4
1Dept. of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ²Dept. of Medical and Biological Informatics, German Cancer Research Center (DKFZ), Heidelberg, Germany, ³Division of Pediatric Pulmonology & Allergy and Cystic Fibrosis Center, University Hospital Heidelberg, Heidelberg, Germany, ⁴Dept. of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany, ⁵Clinics for Interventional and Diagnostic Radiology, Chest Clinics at the University of Heidelberg, Germany

The aim of this work was to validate an automated scoring system of regional perfusion defects for data acquired by using a non-contrast-enhanced technique of Fourier decomposition 1H MRI (FD-MRI) in a group of cystic fibrosis (CF) patients. This work proves that automated assessment of regional perfusion defects in CF patients with FD-MRI is feasible and comparable to visual scoring. This diagnostic method could be well suited for reproducible and reader independent detection of early functional impairment and noninvasive monitoring of therapy response.

Yoshiharu Ohno^1,2, Mizuho Nishio¹, Hisanobu Koyama^1,2, Takeshi Yoshikawa¹, Sumiaki Matsumoto¹, Daisuke Takenaka¹, Katsusuke Kyotani², Nobukazu Aoyama², Hideaki Kawamitsu², Makoto Obara³, Marc van Cauteren⁴, and Kazuro Sugimura^1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, ²Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, ³Philips Electronics Japan, Tokyo, Japan, ⁴Philips Healthcare Asia Pacific, Tokyo, Japan

O2-enhanced MRI can assess regional ventilation and alveolocapillary gas transfer of molecular oxygen. However, none of these studies have examined the quantitative and qualitative capabilities of O2-enhanced MRI for evaluation of candidates for lung volume reduction surgery (LVRS), and compared with that of evaluation by means of thin-section MDCT and perfusion SPECT/CT. The purpose of the study was thus to prospectively and directly compare the quantitative and qualitative capabilities of O2-enhanced MRI, thin-section MDCT and perfusion SPECT/CT to predict therapeutic outcomes for LVRS candidates.

Kevin Michael Johnson¹, Scott K Nagle^1,2, and Sean B Fain^1,2
1Medical Physics, University of Wisconsin-Madsion, Madison, WI, United States, ²Radiology, University of Wisconsin-Madison, Madison, WI, United States

Detailed lung structure is poorly visualized with conventional MRI due to low tissue density and rapid signal decay. Ultra-short echo time (UTE) imaging has long held promise to dramatically enhance signal from short T2/T2* species. Due to a long T1 and low tissue density, 3D UTE lung imaging remains extraordinarily sensitive to artifacts from Gibbs ringing, physiological motion, eddy current induced errors, and low signal to noise ratio (SNR). In this work, we develop a robust technique for free-breathing, high-resolution 3D UTE imaging that aims to mitigate sources of diagnostically obscuring artifacts.

Andrea Bianchi¹, François Lux², Gael Dournes¹, Olivier Tillement², and Yannick Crémillieux^1
1Center of Cardio-Thoracic Research, University of Bordeaux Segalen, Bordeaux, France, ²Laboratoire de Physico-Chimie des Matériaux Luminescents, Université Lyon 1, Lyon, France

In this study we present the MRI investigation of the T1-enhancement of the lung signal due to the intra-tracheal administration of different concentrations of a silica-based gadolinium contrast agent, characterized by ultra-small nanoparticles and high relaxivity. The MRI investigation of the temporal evolution of the signal enhancement is also presented to get an estimate of the contrast agent residence time in the lungs. Notably high signal enhancements (> 200% for a 50 mM solution) with relatively small instilled volumes (50 µl) have been measured thanks to the high S/N and the negligibility of motion artifacts, typical of the UTE sequence.

Sara Reis^1,2, Kai Ruppert¹, Talissa Altes¹, John Mugler III¹, Iulian Ruset³, Wilson Miller¹, William Hersman³, and Jaime Mata^1
1Radiology & Medical Imaging, University of Virginia, Charlottesville, Virginia, United States, ²IBEB - FCUL, Universidade de Lisboa, Lisboa, Portugal,³Xemed, New Hampshire, United States

From the Xe-129 CSI data, we directly calculate image-maps reflecting the amount of Xe-129 in the airspaces (gas), and dissolved in the lung tissue (parenchyma/plasma), red-blood-cells (RBC), and other compartments, thus obtaining detailed spatial information regarding how Xe-129 is distributed in these multiple compartments and providing regional information about lung physiology. Here we demonstrate that Xe-129 3D-CSI technique can be a very useful and unique clinical tool for lung disease, capable to obtain more regional information than current clinical tools.

Miranda Kirby^1,2, Andrew Wheatley¹, Adam Farag¹, Alexei Ouriadov¹, Giles E Santyr¹, David G McCormack³, and Grace Parraga^1,2
1Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada, ²Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, ³Division of Respirology, Department of Medicine, The University of Western Ontario

The objective of this study was to compare hyperpolarized helium-3 (³He) and hyperpolarized xenon-129 (¹²⁹Xe) magnetic resonance imaging (MRI) in chronic obstructive pulmonary disease (COPD) ex-smokers and age-matched never-smokers. ³He and ¹²⁹Xe images were segmented using image segmentation/registration software. In 10 COPD subjects and 8 never-smokers, ¹²⁹Xe ventilation defect percent (VDP) was statistically significantly higher than ³He VDP (p<.0001). This finding suggests that ¹²⁹Xe may be more sensitive to the structural alternations that occur in the distal terminal and respiratory bronchioles and is a feasible alternative to ³He MRI with strong translational potential in COPD studies.

Wei Wang^1,2, Nguyet M. Nguyen³, Jinbang Guo¹, Yulin Chang², Dmitriy A. Yablonskiy², Richard A. Pierce³, and Jason C. Woods^1,2
1Physics, Washington University in St. Louis, St. Louis, MO, United States, ²Radiology, Washington University in St. Louis, St. Louis, MO, United States,³Internal Medicine, Washington University in St. Louis

Pneumonectomy (PNX) is a robust, established model of compensatory lung growth. Understanding the time course and the mechanism of compensatory lung growth will promote understanding of post-natal lung growth and regeneration. ³He lung morphometry has been successfully implemented in humans for years, and was recently developed and validated in mice. Here we image in-vivo morphometry at baseline and serially assess compensatory growth after PNX in mice via ¹H and ³He MRI. The results demonstrate that in addition to growth of alveolar size, the total lung volume, alveolar number and lung compliance are restored to baseline levels by compensatory lung growth.

Helen Marshall¹, Martin H Deppe¹, Juan Parra-Robles¹, and Jim M Wild^1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

³He pO₂ mapping assumes that all signal decay over time is due to RF depolarisation and oxygen-dependent T₁ effects, but the method is sensitive to other sources of signal change. Ten patients with moderate to severe COPD were scanned with a 3D single breath-hold pO₂ sequence. Data showed signal increasing over time in some lung regions due to delayed ventilation during static breathold. Movement of gas within the lungs during breath-hold causes regional changes in signal over time, which are not related to oxygen concentration, leading to erroneous pO₂ measurements.

Mathieu Sarracanie^1,2, Andrew Martin³, Marion Tardieu², Najat Salameh², Roberta Santarelli², Kyle Hill⁴, Jose-Manuel Perez-Sanchez², Julien Sandeau⁵, Lionel Martin², Emmanuel Durand², Georges Caillibotte³, Daniel Isabey⁵, Luc Darrasse², Jacques Bittoun², and Xavier Maître^2
1Harvard University Department of Physics, Martinos Center for Biomedical Imaging, Charlestown, Massachussets, United States, ²IR4M (UMR8081), Univ Paris-Sud, CNRS, Orsay, France, ³Centre de Recherche Claude Delorme (CRCD), Air Liquide, Les Loges-en-Josas, France, ⁴Oxford Univ, Oxford MRI Centre, Oxford University, Oxford, United Kingdom, ⁵Biomécanique Cellulaire et Respiratoire (U955), IMRB, Inserm, Créteil, France

Systemic delivery across the oronasal route is investigated for a growing number of indications. Final drug distribution in the lung strongly depends on a variety of parameters like the aerosol administration protocol, particle size, density, and physicochemical properties, as well as the airway geometry. Quantification and spatial localization are of critical importance to better control and optimize drug deposition. Hyperpolarized helium-3 MRI has been developed as a powerful tool to quantitatively characterize the lung function and morphology. We present a new imaging modality developed on the grounds of hyperpolarized helium-3 MRI to probe SPIOs labeled aerosols in vivo,in rat lungs.