Assessment of lung microstructure with magnetic resonance imaging of hyperpolarized Helium-3

Schreiber, Laura M.; Morbach, Andreas E.; Stavngaard, Trine; Gast, Klaus; Herweling, Anette; Søgaard, Lise Vejby; Windirsch, Michael; Schmiedeskamp, Jörg; Heußel, Claus Peter; Kauczor, Hans‐Ulrich

doi:10.1016/j.resp.2005.05.002

Cited by 51 publications

(57 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…First, q-space DWS experiments can be performed with only a fraction of the gas needed for DWI. In our studies, q-space DWS measurements were done with only 40 cc of HHe gas, compared to 250 -500cc generally used for DWI (6,7,25). Given the limited world supply of 3 He gas, q-space DWS could make the difference in making hyperpolarized 3 He a viable clinical tool.…”

Section: Discussionmentioning

confidence: 99%

q‐space analysis of lung morphometry in vivo with hyperpolarized³He spectroscopy

Shanbhag

Altes

Miller

et al. 2006

Magnetic Resonance Imaging

View full text Add to dashboard Cite

Purpose:To examine the utility of a 3 He spectroscopic q-space technique for detecting changes in lung morphometry in vivo. Materials and Methods:A diffusion-weighted spectroscopy sequence was used to collect global diffusion data from healthy adults (N ϭ 11), healthy children (N ϭ 5), and chronic obstructive pulmonary disease (COPD) patients (N ϭ 2) using 40 cc of hyperpolarized 3 He gas within a two second breathhold. Displacement probability profiles (DPP) were obtained by Fourier transformation of diffusion data with respect to q. A bi-Gaussian model was used to decompose the DPPs into narrow and broad components, characterized by root-mean-square displacements X rms1 and X rms2 , respectively. Results:In healthy adults, the narrow component (X rms,1 ) of the DPP had a mean displacement of 188 Ϯ 10 m, slightly less than the reported average size of the alveoli. The broad component (X rms,2 ) had a mean value of 474 Ϯ 44 m, comparable to the diameter of the respiratory bronchioles in the acinus. In children, both X rms1 (167 Ϯ 4 m) and X rms2 (382 Ϯ 22 m) compared to healthy adults (P Ͻ 0.01). In COPD patients, the mean displacements were elevated (X rms1 : 265 Ϯ 71 m; X rms2 : 530 Ϯ 109 m) compared to healthy adults. Excellent correlation was found between rms displacements and age (age vs. X rms,1 : r ϭ 0.78, P Ͻ 0.001; age vs. X rms,2 : r ϭ 0.90, P Ͻ 0.001). Conclusion:The q-space parameters agreed remarkably well with published alveolar morphometry data. The results suggest that the technique may be sensitive to disease, as evident from the elevated mean displacements in COPD patients compared to healthy volunteers. Detailed lung microstructural information can be obtained using a very low volume of inhaled 3 He.

show abstract

Section: Discussionmentioning

confidence: 99%

q‐space analysis of lung morphometry in vivo with hyperpolarized³He spectroscopy

Shanbhag

Altes

Miller

et al. 2006

Magnetic Resonance Imaging

View full text Add to dashboard Cite

show abstract

“…Key words: MRI; parallel imaging; helium; lung; phased array coil Lung imaging using hyperpolarized 3 He has received increased attention in the last several years for studying lung diseases (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). So far, functional imaging, e.g., the apparent diffusion coefficient (ADC) or methods to observe the microstructure of the lung (12,13), requires long breath holds (up to 30 sec), which are the main barrier to applying this technology to patients with severe lung disease. Improvements in array coil methodology are a promising approach for increasing signal-to-noise ratio (SNR) and allowing significant acceleration of the image-encoding process.…”

mentioning

confidence: 99%

Design and evaluation of a 32‐channel phased‐array coil for lung imaging with hyperpolarized 3‐helium

Meise

Rivoire

Terekhov

et al. 2010

Magnetic Resonance in Med

View full text Add to dashboard Cite

Imaging with hyperpolarized 3-helium is becoming an increasingly important technique for MRI diagnostics of the lung but is hampered by long breath holds (>20 sec), which are not always applicable in patients with severe lung disease like chronic obstructive pulmonary disease (COPD) or a-1-anti-trypsin deficiency. Additionally, oxygen-induced depolarization decay during the long breath holds complicates interpretation of functional data such as apparent diffusion coefficients. To address these issues, we describe and validate a 1.5-T, 32-channel array coil for accelerated 3 He lung imaging and demonstrate its ability to speed up imaging 3 He. A signal-to-noise ratio increase of up to a factor of 17 was observed compared to a conventional double-resonant birdcage for unaccelerated imaging, potentially allowing increased image resolution or decreased gas production requirements. Accelerated imaging of the whole lung with one-dimensional and two-dimensional acceleration factors of 4 and 4 3 2, respectively, was achieved while still retaining excellent image quality. Key words: MRI; parallel imaging; helium; lung; phased array coil Lung imaging using hyperpolarized 3 He has received increased attention in the last several years for studying lung diseases (1-12). So far, functional imaging, e.g., the apparent diffusion coefficient (ADC) or methods to observe the microstructure of the lung (12,13), requires long breath holds (up to 30 sec), which are the main barrier to applying this technology to patients with severe lung disease. Improvements in array coil methodology are a promising approach for increasing signal-to-noise ratio (SNR) and allowing significant acceleration of the image-encoding process. Lee et al. (14,15) presented a 24-channel array and later a 128-channel array for 3 He imaging, which demonstrated the feasibility of this approach. The acceleration afforded by parallel imaging is particularly important for hyperpolarized gas imaging since the nonequilibrium state of the magnetization allows faster imaging, often without incurring the standard SNR penalty proportional to the square root of imaging time (16). To analyze the improvements of these techniques in more detail, a 32-channel phased array was designed and built. For comparison, imaging protocols such as used in the European Community Framework V project ''Polarized Helium Imaging of the Lung'' were applied, as well as newly developed protocols, which utilize the extra sensitivity of the array. The sensitivity improvements were compared to a single-channel volume coil and the benefits of parallel imaging for lung diagnostics were analyzed by theoretical geometry-factor (g-factor) maps for the array and demonstrated in accelerated imaging. MATERIALS AND METHODS CoilsThe phased-array coil (Fig. 1) consists of 32 loops mounted on a clamshell former, which was presented by Schmitt et al. (17) for cardiac imaging. The 32 receive elements were milled from 35-lm copper-plated 1.5mm-thick FR4 circuit board material and arranged in two groups of 16 ele...

show abstract

“…The ratio of these polarization changes allow the spatial mapping of ADC, with higher values allocated to larger air spaces (such as trachea and large bronchi). (190) ADC is homogeneously distributed in normal subjects, and becomes progressively more heterogeneous with normal smokers to emphysema (191)(192)(193)(194). ADC has been shown to increase under the influence of aging (195,196), emphysema (194,197,198) and due to gravity dependent compression of the lung (199); Figure 11).…”

Section: Hyperpolarized Gas Imagingmentioning

confidence: 99%

Functional Imaging: CT and MRI

Beek

Hoffman

2008

Clinics in Chest Medicine

View full text Add to dashboard Cite

Synopsis-Numerous imaging techniques permit evaluation of regional pulmonary function. Contrast-enhanced CT methods now allow assessment of vasculature and lung perfusion. Techniques using spirometric controlled MDCT allow for quantification of presence and distribution of parenchymal and airway pathology, Xenon gas can be employed to assess regional ventilation of the lungs and rapid bolus injections of iodinated contrast agent can provide quantitative measure of regional parenchymal perfusion. Advances in magnetic resonance imaging (MRI) of the lung include gadolinium-enhanced perfusion imaging and hyperpolarized helium imaging, which can allow imaging of pulmonary ventilation and .measurement of the size of emphysematous spaces.

show abstract

Assessment of lung microstructure with magnetic resonance imaging of hyperpolarized Helium-3

Cited by 51 publications

References 41 publications

q‐space analysis of lung morphometry in vivo with hyperpolarized³He spectroscopy

q‐space analysis of lung morphometry in vivo with hyperpolarized³He spectroscopy

Design and evaluation of a 32‐channel phased‐array coil for lung imaging with hyperpolarized 3‐helium

Functional Imaging: CT and MRI

Contact Info

Product

Resources

About

Assessment of lung microstructure with magnetic resonance imaging of hyperpolarized Helium-3

Cited by 51 publications

References 41 publications

q‐space analysis of lung morphometry in vivo with hyperpolarized3He spectroscopy

q‐space analysis of lung morphometry in vivo with hyperpolarized3He spectroscopy

Design and evaluation of a 32‐channel phased‐array coil for lung imaging with hyperpolarized 3‐helium

Functional Imaging: CT and MRI

Contact Info

Product

Resources

About

q‐space analysis of lung morphometry in vivo with hyperpolarized³He spectroscopy

q‐space analysis of lung morphometry in vivo with hyperpolarized³He spectroscopy