xenon-129-atom and Idiopathic-Pulmonary-Fibrosis

3D Single-breath Chemical Shift Imaging (3D-SBCSI) is a hybrid MR-spectroscopic imaging modality that uses hyperpolarized xenon-129 gas (Xe-129) to differentiate lung diseases by probing functional characteristics. This study tests the efficacy of 3D-SBCSI in differentiating physiology among pulmonary diseases. A total of 45 subjects-16 healthy, 11 idiopathic pulmonary fibrosis (IPF), 13 cystic fibrosis (CF), and 5 chronic obstructive pulmonary disease (COPD)-were given 1/3 forced vital capacity (FVC) of hyperpolarized Xe-129, inhaled for a ~7 s MRI acquisition. Proton, Xe-129 ventilation, and 3D-SBCSI images were acquired with separate breath-holds using a radiofrequency chest coil tuned to Xe-129. The Xe-129 spectrum was analyzed in each lung voxel for ratios of spectroscopic peaks, chemical shifts, and T2* relaxation. CF and COPD subjects had significantly more ventilation defects than IPF and healthy subjects, which correlated with FEV1 predicted (R = -0.74). FEV1 predicted correlated well with RBC/Gas ratio (R = 0.67). COPD and IPF had significantly higher Tissue/RBC ratios than other subjects, longer RBC T2* relaxation times, and greater RBC chemical shifts. CF subjects had more ventilation defects than healthy subjects, elevated Tissue/RBC ratio, shorter Tissue T2* relaxation, and greater RBC chemical shift. 3D-SBCSI may be helpful in the detection and characterization of pulmonary disease, following treatment efficacy, and predicting disease outcomes.

Topics: Cystic Fibrosis; Gases; Humans; Idiopathic Pulmonary Fibrosis; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Protons; Pulmonary Disease, Chronic Obstructive

Idiopathic pulmonary fibrosis, a pattern of interstitial lung disease, is often clinically unpredictable in its progression. This paper presents hyperpolarized Xenon-129 chemical shift imaging as a noninvasive, nonradioactive method of probing lung physiology as well as anatomy to monitor subtle changes in subjects with IPF. Twenty subjects, nine healthy and eleven IPF, underwent HP Xe-129 ventilation MRI and 3D-SBCSI. Spirometry was performed on all subjects before imaging, and DLCO and hematocrit were measured in IPF subjects after imaging. Images were post-processed in MATLAB and segmented using ANTs. IPF subjects exhibited, on average, higher Tissue/Gas ratios and lower RBC/Gas ratios compared with healthy subjects, and quantitative maps were more heterogeneous in IPF subjects. The higher ratios are likely due to fibrosis and thickening of the pulmonary interstitium. T2* relaxation was longer in IPF subjects and corresponded with hematocrit scores, although the mechanism is not well understood. A lower chemical shift in the red blood cell spectroscopic peak correlated well with a higher Tissue/RBC ratio and may be explained by reduced blood oxygenation. Tissue/RBC also correlated well, spatially, with areas of fibrosis in HRCT images. These results may help us understand the underlying mechanism behind gas exchange impairment and disease progression.

Topics: Humans; Idiopathic Pulmonary Fibrosis; Lung; Magnetic Resonance Imaging; Xenon Isotopes

The spectral parameters of hyperpolarized

Topics: Adult; Aged; Erythrocytes; Female; Humans; Idiopathic Pulmonary Fibrosis; Magnetic Resonance Spectroscopy; Male; Middle Aged; Time Factors; Xenon Isotopes; Young Adult

Assessing functional impairment, therapeutic response and disease progression in patients with idiopathic pulmonary fibrosis (IPF) continues to be challenging. Hyperpolarized. 13 healthy individuals (33.6±15.7 years) and 12 patients with IPF (66.0±6.4 years) underwent. Hyperpolarized

Topics: Adult; Aged; Case-Control Studies; Erythrocytes; Female; Humans; Idiopathic Pulmonary Fibrosis; Imaging, Three-Dimensional; Magnetic Resonance Imaging; Male; Middle Aged; Pulmonary Gas Exchange; Respiratory Function Tests; Xenon Isotopes; Young Adult

A novel technique is presented for retrospective estimation and removal of gas-phase hyperpolarized Xenon-129 (HP. Digital lung phantom and human subject experiments (N = 8 healthy; N = 1 with idiopathic pulmonary fibrosis) were acquired with 3D radial trajectory and 1-point Dixon spectroscopic imaging to assess the correction method for mitigating barrier and RBC imaging artifacts. Dependence of performance on TE, image SNR, and gas contamination level were characterized. Inter- and intra-subject variation in the dissolved-phase ratios were quantified and compared to human subject experiments before and after correction.. Gas contamination resulted in image artifacts similar to those in disease that were mitigated after correction in both simulated and human subject data; for simulation experiments performance varied with TE, but was independent of image SNR and the amount of gas contamination. Artifacts and variation of barrier and RBC components were reduced after correction in both simulation and healthy human lungs (barrier, P = 0.01; RBC, P = 0.045).. The proposed technique significantly reduced regional variations in barrier and RBC ratios, separated using a 1-point Dixon approach, with improved accuracy of dissolved-phase HP

Topics: Adult; Aged; Artifacts; Computer Simulation; Erythrocytes; Female; Gases; Humans; Idiopathic Pulmonary Fibrosis; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Lung; Male; Middle Aged; Phantoms, Imaging; Retrospective Studies; Signal-To-Noise Ratio; Spectrophotometry; Xenon Isotopes

Hyperpolarized. Seven healthy subjects and six patients with pulmonary disorders were recruited to characterize. A 0.69 ms sinc was found to generate minimal off-resonance gas-phase excitation (3.0 ± 0.3% of the dissolved-phase), yielding a TE. Despite short dissolved-phase

Topics: Adult; Aged; Algorithms; alpha 1-Antitrypsin; Carcinoma, Non-Small-Cell Lung; Erythrocytes; Female; Gases; Heterozygote; Humans; Hypertension, Pulmonary; Idiopathic Pulmonary Fibrosis; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Lung Diseases; Lung Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Mutation; Pulmonary Disease, Chronic Obstructive; Respiration; Solubility; Xenon Isotopes; Young Adult