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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,441 records · Page 80
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Uterine Artery Embolization versus Myomectomy: Impact on Quality of Life-Results of the FUME (Fibroids of the Uterus: Myomectomy versus Embolization) Trial

Purpose: This study was designed to compare quality of life (QoL) outcomes after uterine artery embolization (UAE) or myomectomy. Methods: Women with symptomatic fibroids diagnosed by ultrasound who wished to preserve their uterus were randomized to myomectomy (n = 81) or UAE (n = 82). Endpoints at 1 year were QoL measured by a validated questionnaire, hospital stay, rates of complications, and need for reintervention. Results: UAE patients had shorter hospitalization (2 vs. 6 days, p < 0.001). By 1 year postintervention, significant and equal improvements in QoL scores had occurred in both groups (myomectomy n = 59; UAE n = 61). There had been two (2.9%) major complications among UAE versus 6 (8%) among myomectomy patients (not significant). By 2 years, among UAE patients (n = 57) there were eight (14.0%) reinterventions for inadequate symptom control compared with one (2.7%) among myomectomy patients (n = 37). Half of the women who required hysterectomy had concomitant adenomyosis missed by US. Conclusions: UAE and myomectomy both result in significant and equal improvements in QoL. UAE allows a shorter hospital stay and fewer major complications but with a higher rate of reintervention.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Oversizing and Restenosis with Self-Expanding Stents in Iliofemoral Arteries

Purpose: Uncoated self-expanding nitinol stents (NS) are commonly oversized in peripheral arteries. In current practice, 1-mm oversizing is recommended. Yet, oversizing of NS may be associated with increased restenosis. To provide further evidence, NS were implanted in porcine iliofemoral arteries with a stent-to-artery-ratio between 1.0 and 2.3. Besides conventional uncoated NS, a novel self-expanding NS with an antiproliferative titanium-nitride-oxide (TiNOX) coating was tested for safety and efficacy. Methods: Ten uncoated NS and six TiNOX-coated NS (5-6 mm) were implanted randomly in the iliofemoral artery of six mini-pigs. After implantation, quantitative angiography (QA) was performed for calculation of artery and minimal luminal diameter. Follow-up was performed by QA and histomorphometry after 5 months. Results: Stent migration, stent fracture, or thrombus formation were not observed. All stents were patent at follow-up. Based on the location of the stent (iliac/femoral) and the stent-to-artery-ratio, stent segments were divided into 'normal-sized' (stent-to-artery-ratio < 1.4, n = 12) and 'oversized' (stent-to-artery-ratio {>=} 1.4, n = 9). All stent segments expanded to their near nominal diameter during follow-up. Normal-sized stent segments increased their diameter by 6% and oversized segments by 29%. A significant correlation between oversizing and restenosis by both angiography and histomorphometry was observed. Restenosis rates were similar for uncoated NS and TiNOX-coated NS. Conclusions: TiNOX-coated NS are as safe and effective as uncoated NS in the porcine iliofemoral artery. All stents further expand to near their nominal diameter during follow-up. Oversizing is linearly and positively correlated with neointimal proliferation and restenosis, which may not be reduced by TiNOX-coating.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

A unique but flexible space–time could challenge multiverse theories

Highlights: The growing law of a billiard multiverse is independent of the discretization scale E. The time for any final state to be accessible from any initial one is around 3E shocks. The paths of billiard balls can change without changing initial or final states. Space-time flexibility can be achieved through paths commutations and entanglement. -- Abstract: In a previous paper (Guillemant et al., 2018), we have shown using a 2D billiard toy model that the propagation of uncertainties resulting from space–time discretization leads to a classical multiverse. In this one we estimate the growing law of the number of its branches, thanks to an original shock indexation method that permits a very fast comparison of trajectories. For different involved parameters we use random sets of infinitesimally perturbed initial conditions. From each set, we compute a collection up to hundred millions of different billiard histories. Our main result is the calculation of a Brownian saturation time when the number of branches begins to exceed the total number of billiard states. We discuss the possibility suggested by this result to change locally the paths of objects without changing their past and future histories and then subverting their global system. We conclude that a unique but flexible space–time could compete with the current many-worlds interpretation claiming that each branch is a different universe.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2012

Barriers to the Implementation of Surveillance for Stage I Testicular Seminoma

Purpose: Postorchiectomy adjuvant radiotherapy (RT) for Stage I seminoma can be associated with long-term toxicity, and management strategies with a lower treatment burden achieve the same excellent cure rate. Because studies suggest that radiation oncologists in the United States continue to recommend RT for these patients, we sought to identify factors associated with management recommendations. Methods and Materials: We conducted a one-time internet-based survey among 491 randomly selected American radiation oncologists self-described as specializing in genitourinary oncology. Results: Response rate was 53% (n = 261). Forty-nine percent of respondents worked in university-affiliated practices. Sixty-two percent of respondents always/usually recommended adjuvant RT for patients with Stage I seminoma, whereas 21% always/usually recommended surveillance and 3% always/usually recommended chemotherapy. One third (33%) expressed concerns that patients who experienced relapse during surveillance could not be salvaged. Although 88% of physicians were aware of an increased risk of second malignant neoplasms (SMN) after adjuvant RT, 85% underestimated its magnitude. Compared with physicians not typically recommending RT, physicians who always/usually recommended RT were more likely to believe that patients might not be salvaged at relapse during surveillance (p = 0.008) and were less aware of the association between RT and SMN (p = 0.04). Conclusions: Respondents who always/usually recommend postorchiectomy RT for patients with Stage I seminoma are more likely to underestimate late RT morbidity and to believe that surveillance is associated with increased mortality. Given the equivalent efficacy and reduced morbidity of surveillance compared with RT, our findings underscore the need for ongoing physician education to increase appropriate clinical implementation of surveillance strategies.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

A Prospective Comparison of the Effects of Interfractional Variations on Proton Therapy and Intensity Modulated Radiation Therapy for Prostate Cancer

Purpose: To quantify and compare the impact of interfractional setup and anatomic variations on proton therapy (PT) and intensity modulated radiation therapy (IMRT) for prostate cancer. Methods and Materials: Twenty patients with low-risk or intermediate-risk prostate cancer randomized to receive passive-scattering PT (n=10) and IMRT (n=10) were selected. For both modalities, clinical treatment plans included 50.4 Gy(RBE) to prostate and proximal seminal vesicles, and prostate-only boost to 79.2 Gy(RBE) in 1.8 Gy(RBE) per fraction. Implanted fiducials were used for prostate localization and endorectal balloons were used for immobilization. Patients in PT and IMRT arms received weekly computed tomography (CT) and cone beam CT (CBCT) scans, respectively. The planned dose was recalculated on each weekly image, scaled, and mapped onto the planning CT using deformable registration. The resulting accumulated dose distribution over the entire treatment course was compared with the planned dose using dose-volume histogram (DVH) and γ analysis. Results: The target conformity index remained acceptable after accumulation. The largest decrease in the average prostate D{sub 98} was 2.2 and 0.7 Gy for PT and IMRT, respectively. On average, the mean dose to bladder increased by 3.26 ± 7.51 Gy and 1.97 ± 6.84 Gy for PT and IMRT, respectively. These values were 0.74 ± 2.37 and 0.56 ± 1.90 for rectum. Differences between changes in DVH indices were not statistically significant between modalities. All volume indices remained within the protocol tolerances after accumulation. The average pass rate for the γ analysis, assuming tolerances of 3 mm and 3%, for clinical target volume, bladder, rectum, and whole patient for PT/IMRT were 100/100, 92.6/99, 99.2/100, and 97.2/99.4, respectively. Conclusion: The differences in target coverage and organs at risk dose deviations for PT and IMRT were not statistically significant under the guidelines of this protocol.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

The 2-Year Cosmetic Outcome of a Randomized Trial Comparing Prone and Supine Whole-Breast Irradiation in Large-Breasted Women

Purpose: To report the 2-year cosmetic outcome of a randomized trial comparing prone and supine whole-breast irradiation in large-breasted patients. Methods and Materials: One hundred patients with a (European) cup size ≥C were included. Before and 2 years after radiation therapy, clinical endpoints were scored and digital photographs were taken with the arms alongside the body and with the arms elevated 180°. Three observers rated the photographs using the 4-point Harvard cosmesis scale. Cosmesis was also evaluated with the commercially available Breast Cancer Conservation Treatment.cosmetic results (BCCT.core) software. Results: Two-year follow-up data and photographs were available for 94 patients (47 supine treated and 47 prone treated). Patient and treatment characteristics were not significantly different between the 2 cohorts. A worsening of color change occurred more frequently in the supine than in the prone cohort (19/46 vs 10/46 patients, respectively, P=.04). Five patients in the prone group (11%) and 12 patients in the supine group (26%) presented with a worse scoring of edema at 2-year follow-up (P=.06). For retraction and fibrosis, no significant differences were found between the 2 cohorts, although scores were generally worse in the supine cohort. The cosmetic scoring by 3 observers did not reveal differences between the prone and supine groups. On the photographs with the hands up, 7 patients in the supine group versus none in the prone group had a worsening of cosmesis of 2 categories using the (BCCT.org) software (P=.02). Conclusion: With a limited follow-up of 2 years, better cosmetic outcome was observed in prone-treated than in supine-treated patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Radical Cystectomy Compared to Combined Modality Treatment for Muscle-Invasive Bladder Cancer: A Systematic Review and Meta-Analysis

Purpose: To perform a comprehensive comparison of overall survival (OS), disease-specific survival (DSS), progression-free survival (PFS), and treatment-related complications between radical cystectomy (RC) and combined modality treatment (CMT—radiation therapy, concurrent chemotherapy, and maximal transurethral resection of bladder tumor) in the setting of muscle-invasive bladder cancer. Methods and Materials: We searched 7 databases (PubMed, Scopus, EMBASE, Proquest, CINAHL, and (ClinicalTrials.gov)) for randomized, controlled trials and prospective and retrospective studies directly comparing RC with CMT from database inception to March 2016. We conducted meta-analyses evaluating OS, DSS, and PFS with hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Nineteen studies evaluating 12,380 subjects were selected. For the 8 studies encompassing 9554 subjects eligible for meta-analyses, we found no difference in OS at 5 years (HR 0.96, favoring CMT, 95% CI 0.72-1.29; P=.778) or 10 years (HR 1.02, favoring cystectomy, 95% CI 0.73-1.42; P=.905). No difference was observed in DSS at 5 years (HR 0.83, favoring radiation, 95% CI 0.54-1.28; P=.390) or 10 years (HR 1.17, favoring cystectomy, 95% CI 0.89-1.55; P=.264), or PFS at 10 years (HR 0.85, favoring CMT, 95% CI 0.43-1.67; P=.639). The cystectomy arms had higher rates of early major complications, whereas rates of minor complications were similar between the 2 treatments. Conclusion: Current meta-analysis reveals no differences in OS, DSS, or PFS between RC and CMT. Further randomized, controlled trials are necessary to identify the optimal treatment for specific patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Reporting Quality of Randomized, Controlled Trials Evaluating Combined Chemoradiotherapy in Nasopharyngeal Carcinoma

Purpose: To comprehensively assess the reporting quality of randomized, controlled trials (RCTs) in nasopharyngeal carcinoma (NPC), and to identify significant predictors of quality. Methods and Materials: Two investigators searched MEDLINE and EMBASE for RCTs published between January 1988 and December 2015 that assessed the effect of combined chemoradiotherapy for NPC. The overall quality of each report was assessed using a 28-point overall quality score (OQS) based on the 2010 Consolidated Standards of Reporting Trials (CONSORT) statement. To provide baseline data for further evaluation, we also investigated the reporting quality of certain important issues in detail, including key methodologic items (allocation concealment, blinding, intention-to-treat principle), endpoints, follow-up, subgroup analyses, and adverse events. Results: We retrieved 24 relevant RCTs including 6591 patients. Median 2010 OQS was 15.5 (range, 10-24). Half of the items in the 2010 OQS were poorly reported in at least 40% of trials. Multivariable regression models revealed that publication after 2010 and high impact factor were significant predictors of improved 2010 OQS. Additionally, many issues that we consider significant were not reported adequately. Conclusions: Despite publication of the CONSORT statement more than a decade ago, overall reporting quality for RCTs in NPC was unsatisfactory. Additionally, substantial selectivity and heterogeneity exists in reporting of certain crucial issues. This survey provides the first prompt for NPC trial investigators to improve reporting quality according to the CONSORT statement; increased scrutiny and diligence by editors and peer reviewers is also required.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

A cell-local finite difference discretization of the low-order quasidiffusion equations for neutral particle transport on unstructured quadrilateral meshes

We present a quasidiffusion (QD) method for solving neutral particle transport problems in Cartesian XY geometry on unstructured quadrilateral meshes, including local refinement capability. Neutral particle transport problems are central to many applications including nuclear reactor design, radiation safety, astrophysics, medical imaging, radiotherapy, nuclear fuel transport/storage, shielding design, and oil well-logging. The primary development is a new discretization of the low-order QD (LOQD) equations based on cell-local finite differences. The accuracy of the LOQD equations depends on proper calculation of special non-linear QD (Eddington) factors from a transport solution. In order to completely define the new QD method, a proper discretization of the transport problem is also presented. The transport equation is discretized by a conservative method of short characteristics with a novel linear approximation of the scattering source term and monotonic, parabolic representation of the angular flux on incoming faces. Analytic and numerical tests are used to test the accuracy and spatial convergence of the non-linear method. All tests exhibit O(h{sup 2}) convergence of the scalar flux on orthogonal, random, and multi-level meshes.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2021

Mechanistic verification of empirical UO 2 fuel fracture models

Standard UO 2 fuel pellets used in light-water reactors fracture during irradiation due to the large thermal gradient in the radial direction. Over the decades, numerous researchers have explored fuel cracking from experimental and modeling points of view. To date, there have been both empirical and mechanistic approaches to predict the number of fragments that form in UO 2 . The empirical models only consider maximum power and burnup as inputs. Existing mechanistic approaches for normal operation have not accounted for irradiation effects. Here, this work employs a mechanistic fuel cracking model using the extended finite element method to explore radial crack formation while including a sensitivity analysis that accounts for the randomization of tensile strength within the fuel, the strength randomization criteria (uniform or volume-weighted Weibull), power ramping rates, computational mesh density, maximum power level, and irradiation (burnup) effects. The results indicate that the uncertainty in this mechanistic modeling approach envelopes the predicted values from three different empirical correlations in almost all cases. This means that, for computationally intensive analyses involving UO 2 fragmentation, the empirical correlations can be used. However, since the mechanistic calculations bound those of the empirical correlations, there is confidence in the applicability of the mechanistic approach developed in this work to generate a correlation for fuel types where limited data exists (e.g., doped-UO 2 , U 3 Si 2 ).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2025

Uncertainty propagation in feed-forward neural network models

We develop new uncertainty propagation methods for feed-forward neural network architectures with leaky ReLU activation functions subject to random perturbations in the input vectors. In particular, we derive analytical expressions for the probability density function (PDF) of the neural network output and its statistical moments as a function of the input uncertainty and the parameters of the network, i.e., weights and biases. A key finding is that an appropriate linearization of the leaky ReLU activation function yields accurate statistical results even for large perturbations in the input vectors. This can be attributed to the way information propagates through the network. We also propose new analytically tractable Gaussian copula surrogate models to approximate the full joint PDF of the neural network output. To validate our theoretical results, we conduct Monte Carlo simulations and a thorough error analysis on a multi-layer neural network representing a nonlinear integro-differential operator between two polynomial function spaces. Our findings demonstrate excellent agreement between the theoretical predictions and Monte Carlo simulations.

MLP networks↗
DOE OSTI2024

The influence of the shock-to-reshock time on the Richtmyer–Meshkov instability in reshock

Experiments on the Richtmyer–Meshkov instability (RMI) in a dual driver vertical shock tube (DDVST) are described. An initially planar, stably stratified membraneless interface is formed by flowing air from above and sulfur hexafluoride from below the interface location using the method of Jones & Jacobs ( Phys. Fluids , vol. 9, issue 1997, 1997, pp. 3078–3085). A random three-dimensional, multi-modal initial perturbation is imposed by vertically oscillating the gas column to produce Faraday waves. The DDVST design generates two shock waves, one originating above and one below the interface, with these shocks having independently controllable strengths and interface arrival times. The shock waves have nominal strengths of $M_L=1.17$ and $M_H=1.18$ for the shock wave originating in the light and heavy gas, respectively, with these strengths chosen to result in arrested bulk interface motion following reshock. The influence of the length of the shock-to-reshock time, as well as the order of shock arrival, on the post-reshock RMI is examined. The mixing layer width grows according to $h\propto t^\theta$ , where $\theta _H=0.36\pm 0.018$ (95 %) and $\theta _L=0.38\pm 0.02$ (95 %) for heavy and light shock first experiments, respectively, indicating no strong dependence on the order of shock wave arrival. Volume integrated specific turbulent kinetic energy (TKE) in the mixing layer versus time is found to decay according to $E_{tot}/\bar {\rho }\propto t^p$ with $p_H=-0.823\pm 0.06$ (95 %) and $p_L=-1.061\pm 0.032$ (95 %) for heavy and light shock first experiments, respectively. Notably, the 95 % confidence intervals do not overlap. Analysis on the influence of the shock-to-reshock time on turbulent length scales, transition criteria, spectra and mixing layer anisotropy are also presented.

Ferguson, Kevin (ORCID:0000000166537482)↗
DOE OSTI2012

Joint probabilities and quantum cognition

In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2021

New, improved analysis of correlation ECE data to accurately determine turbulent electron temperature spectra and magnitudes (invited)

Turbulent electron temperature fluctuation measurement using a correlation electron cyclotron emission (CECE) radiometer has become an important diagnostic for studying energy transport in fusion plasmas, and its use is widespread in tokamaks (DIII-D, ASDEX Upgrade, Alcator C-Mod, Tore Supra, EAST, TCV, HL-2A, etc.). The CECE diagnostic typically performs correlation analysis between two closely spaced (within the turbulent correlation length) ECE channels that are dominated by uncorrelated thermal noise emission. This allows electron temperature fluctuations embedded in the thermal noise to be revealed and fluctuation level and spectra determined. We have demonstrated a new, improved CECE coherency-based analysis for calculating the temperature fluctuation frequency spectrum and level, which has been verified both numerically through the simulation of synthetic ECE radiometer data and through analysis of experimental data from the CECE system on DIII-D. The new formulation places coherency-based analysis on a firm foundational footing and corrects some currently published methodologies. This new method accurately accounts for bias error in the coherence function and correctly calculates noise levels for a fixed data record length. It provides excellent accuracy in determining temperature fluctuation level (e.g., <10% error) even for a small realization number in the ensemble average. The method also has a smaller uncertainty (i.e., error bar) in the power spectrum when compared to the more standard cross-power method when evaluated at low coherency. Direct calculation of system noise level using correlation between randomized intermediate frequency signals is recommended.

Wang, G. (ORCID:0000000225739827)↗
DOE OSTI2022

Noniterative finite amplitude methods for E 1 and M 1 giant resonances

The finite amplitude method (FAM) is a very efficient approach for solving the fully self-consistent random-phase approximation (RPA) equations. We use FAM to rederive the RPA matrices for Skyrme functionals, calculate the electric dipole ( E 1) and the magnetic dipole ( M 1) giant resonances, and compare the results with available experimental and evaluated data. For the E 1 transitions in heavy nuclei, the calculations reproduce well the resonance energy of the photoabsorption cross sections. In the case of M 1 transitions, we show that the residual interaction does not affect the transition strength of double-magic nuclei, which suggests that the spin terms in the Skyrme force currently neglected in the present computation could improve the agreement between FAM and experimental data.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2021

Efficient Estimation of Pauli Observables by Derandomization

In this work, we consider the problem of jointly estimating expectation values of many Pauli observables, a crucial subroutine in variational quantum algorithms. Starting with randomized measurements, we propose an efficient derandomization procedure that iteratively replaces random single-qubit measurements by fixed Pauli measurements; the resulting deterministic measurement procedure is guaranteed to perform at least as well as the randomized one. In particular, for estimating any L low-weight Pauli observables, a deterministic measurement on only of order log(L) copies of a quantum state suffices. In some cases, for example, when some of the Pauli observables have high weight, the derandomized procedure is substantially better than the randomized one. Specifically, numerical experiments highlight the advantages of our derandomized protocol over various previous methods for estimating the ground-state energies of small molecules.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2024

Explaining Neural Spike Activity for Simulated Bio-plausible Network through Deep Sequence Learning

With significant improvements in large-scale simulations of brain models, there is a growing need to develop tools for rapid analysis and interpreting the simulation results. In this work, we explore the potential of sequential deep learning models to understand and explain the network dynamics among the neurons extracted from a large-scale neural simulation in STACS (Simulation Tool for Asynchronous Cortical Stream). Our method employs a representative neuroscience model that abstracts the cortical dynamics with a reservoir of randomly connected spiking neurons with a low stable spike firing rate throughout the simulation duration. We subsequently analyze the spike dynamics of the simulated spiking neural network through an autoencoder model and an attention-based mechanism.

Kulkarni, Shruti↗
DOE OSTI2016

TH-CD-202-09: Free-Breathing Proton MRI Functional Lung Avoidance Maps to Guide Radiation Therapy

Purpose: Pulmonary functional MRI using inhaled gas contrast agents was previously investigated as a way to identify well-functioning lung in patients with NSCLC who are clinical candidates for radiotherapy. Hyperpolarized noble-gas ({sup 3}He and {sup 129}Xe) MRI has also been optimized to measure functional lung information, but for a number of reasons, the clinical translation of this approach to guide radiotherapy planning has been limited. As an alternative, free-breathing pulmonary 1H MRI using clinically available MRI systems and pulse sequences provides a non-contrast-enhanced method to generate both ventilation and perfusion maps. Free-breathing {sup 1}H MRI exploits non-rigid registration and Fourier decomposition of MRI signal intensity differences (Bauman et al., MRM, 2009) that may be generated during normal tidal breathing. Here, our objective was to generate free-breathing {sup 1}H MRI ventilation and lung function avoidance maps in patients with NSCLC as a way to guide radiation therapy planning. Methods: Stage IIIA/IIIB NSCLC patients (n=8, 68±9yr) provided written informed consent to a randomized controlled clinical trial ( https://clinicaltrials.gov/ct2/show/NCT02002052 ) that aimed to compare outcomes related to image-guided versus conventional radiation therapy planning. Hyperpolarized {sup 3}He/{sup 129}Xe and dynamic free tidal-breathing {sup 1}H MRI were acquired as previously described (Capaldi et al., Acad Radiol, 2015). Non-rigid registration was performed using the modality-independent-neighbourhood-descriptor (MIND) deformable approach (Heinrich et al., Med Image Anal, 2012). Ventilation-defect-percent ({sup 3}He:VDP{sub He}, {sup 129}Xe:VDP{sub Xe}, Free-breathing-{sup 1}H:VDP{sub FB}) and the corresponding ventilation maps were compared using Pearson correlation coefficients (r) and the Dice similarity coefficient (DSC). Results: VDP{sub FB} was significantly related to VDP{sub He} (r=.71; p=.04) and VDP{sub Xe} (r=.80; p=.01) and there were also strong spatial relationships (DSC{sub He}/DSC{sub Xe}=89±3%/77±11%). Conclusion: In this proof of concept study in NSCLC patients, free-breathing {sup 1}H MRI ventilation defects were quantitatively and spatially related to inhaled-noble-gas MRI ventilation defects. Free-breathing {sup 1}H MRI measures lung function/ventilation that can be used to optimize radiotherapy planning in NSCLC patients.

60 APPLIED LIFE SCIENCES↗