Hyperpolarized Nuclei for NMR Imaging and Spectroscopy - Lunds ...

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DOKUMENTDATABLAD enl SIS 61 41 21 Organization LUND UNIVERSITY Department of Electrical Measurements Lund Institute of Technology Box 118 SE–221 00 Lund, Sweden Author(s) Sven Månsson Document name DOCTORAL DISSERTATION Date of issue 2002–12–13 Sponsoring organization Title and subtitle Hyperpolarized Nuclei for NMR Imaging and Spectroscopy — Methodology and model studies of lung and vascular function Abstract Based on the principle of nuclear magnetic resonance (NMR), magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) are widely used methods in medical diagnostic imaging and biological research. Clinical MRI has been restricted to imaging of protons, for reasons of sensitivity. In recent years, hyperpolarization techniques have emerged that can increase the NMR signal by 5–6 orders of magnitude. The increased signal from hyperpolarized substances enables investigation of non-proton nuclei, and thus makes novel kinds of examinations possible, e.g., imaging of the lungs and respiratory airways after inhalation of hyperpolarized gas. In this work, applications related to vascular imaging and lung function were investigated, using three hyperpolarized nuclei: 129 Xe, 13 C, and 3 He. In addition, practical aspects regarding the handling and utilization of hyperpolarized substances were evaluated. The potential of angiography using echo-planar imaging (EPI) was investigated using dissolved 129 Xe in a phantom model. Long relaxation times were achieved in the in vitro experiments, allowing images of reasonable quality to be acquired within a scan time of 44 ms. Under in vivo conditions, severe limitations are expected, which are mainly due to short transverse relaxation times. A novel 13 C substance with favorable properties for angiography was investigated using an optimized true fast imaging w it h st e ad y- s ta te pr ec es s io n ( t r ue FIS P) pul s e se que nc e. L o ng re la xa t io n t im es we r e o bt a in ed al so u n de r in vi vo co nd it i on s ( T1 ≈ 4 0 s, T2 ≈ 2s), which permitted the acquisition of angiograms in live rats with a signal-to-noise ratio (SNR) as high as ~500. To investigate regional pulmonary ventilation, a technique was developed in an initial study, that was based on inhalation of 3 He gas. A quantitative measurement of gas replacement was calculated from the signal buildup after repeated inspirations of 3 He. The relative replacement of gas was close to 1 in the trachea and the major airways, and decreased to ~0.15 in the most peripheral parts of the lung. In a second study, regional ventilation was found to be increased in the inferior parts of the lung as compared with the superior parts, with the subject in supine position, whereas a uniform ventilation was measured in prone position. From measurements of the dynamic uptake of 129 Xe from the alveolar gas spaces to the pulmonary blood vessels, several physiological parameters could be derived, including the thickness of the respiratory membrane and the pulmonary perfusion. The method was employed to compare healthy control animals with animals with inflammatory lung injury. A significantly increased membrane thickness (10.0 µm vs. 8.6 µm) was measured in the latter group, whereas the pulmonary perfusion remained unaltered. By using hyperpolarized substances, novel possibilities of gaining physiological information arise, which may complement existing MRI and MRS techniques. Key words: Magnetic resonance; hyperpolarized; lung function; 3He; 13C; 129Xe Classification system and/or index terms (if any): Supplementary bibliographical information: Language English ISSN and key title: 0346–6221, Report 1/02 Recipient’s notes Number of pages 172 Security classification ISBN 91–628–5434–8 Distribution by (name and address) Sven Månsson, Dept. of Experimental Research, Malmö University Hospital, SE–205 02 Malmö, Sweden. I, the undersigned, being the copyright owner of the abstract of the above-mentioned dissertation, hereby grant to all reference sources permission to publish and disseminate the abstract of the above-mentioned dissertation. Signature_______________________________________ Date________________________ 2002–11–19 Price
Hyperpolarized Nuclei for NMR Imaging and Spectroscopy Methodology and model studies of lung and vascular function Sven Månsson Department of Experimental Research Malmö University Hospital Lund University 2002
Page 1: ��
Page 6 and 7: Doctoral Dissertation Department of
Page 9 and 10: Abstract Based on the principle of
Page 11 and 12: Original papers This thesis is base
Page 13 and 14: Table of Contents 1 Introduction .
Page 15 and 16: 1 Introduction The phenomenon of nu
Page 17 and 18: By using hyperpolarized imaging age
Page 19 and 20: vector addition of all the magnetic
Page 21 and 22: illustrates the difference between
Page 23 and 24: pumping process (Colegrove and Fran
Page 25 and 26: thetic effects, and has been used a
Page 27 and 28: 1 T 1,O2 p = ξ O2 [11] where ξ Xe
Page 29 and 30: 1 2 2 −6 ∝ γC γHrτ c. [17] T
Page 31 and 32: and thus breaks down at very low fr
Page 33 and 34: 230 mT, e.g., Tseng et al. 1998, Du
Page 35 and 36: lation-perfusion ratio (V · A/Q ·
Page 37 and 38: after gas inhalation, due to the wa
Page 39 and 40: tion of an NMR signal from a small
Page 41 and 42: larized gas with air took place as
Page 43 and 44: Table 5. Parameters of the imaging
Page 45 and 46: The images were evaluated with resp
Page 47 and 48: partial pressure present within the
Page 49 and 50: 3.8.2 Measurement procedure The spe
Page 51 and 52: 4.2 Vascular imaging of a 13 C-base
Page 53 and 54: gions. In central lung areas, regio
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4.5 Diffusion capacity and perfusio
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5 Discussion In this thesis, three
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due to the increased demand on the
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5.3 Hyperpolarized 3 He ventilation
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a theoretical T 1 of ∼38 min in t
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eath-holding periods during, e.g.,
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6 Conclusions The phantom study in
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8 References ABRAGAM A, GOLDMAN M.
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CHEN XJ, MÖLLER HE, CHAWLA MS, COF
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GIERADA DS, SAAM B, YABLONSKIY D, C
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KAUCZOR HU, HANKE A, VAN BEEK EJ. A
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OLSSON LE, MAGNUSSON P, DENINGER AJ
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TILTON RF, JR., KUNTZ ID, JR. Nucle
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Paper I
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formance of the gradient system, si
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S. MÅNSSON ET AL. Fig. 2. a-h) EPI
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though several technical issues rem
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Hyperpolarized 13 C MR angiography
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Introduction The most widespread te
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of the gradient moments prior to ea
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Methods Polarization procedure The
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secutive trueFISP images were acqui
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also to several other sources such
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low γ of 13 C reduces the sensitiv
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9. Chawla MS, Chen XJ, Möller HE,
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My 1 0.8 0.6 0.4 0.2 0 0 50 100 150
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Signal [a.u] 100 90 80 70 60 50 40
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a b Figure 5. Series of angiograms
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Paper III
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224 Deninger et al. FIG. 1. Sketch
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226 Deninger et al. FIG. 2. Coronal
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228 Deninger et al. FIG. 6. Histogr
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230 Deninger et al. FIG. 9. Monte C
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232 Deninger et al. 5. Gur D, Draye
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3 He MRI-based measurement of posit
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Introduction It is well known that
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3 He imaging All experiments were p
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coefficients b 1 and b 2, respectiv
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Using VI data after subtraction of
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To investigate whether the calculat
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14. Gur D, Drayer BP, Borovetz HS,
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Table 1. Gradient of VI [cm −1 ]
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Cycle 1 Cycle 2 Cycle 3 Cycle 4 2 s
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a Prone Ventilation index c Supine
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a Prone Supine 0 b 1 R 2 Prone Supi
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Paper V
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Abstract The ability to quantify pu
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lation and perfusion information by
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Applying the conditions at the inne
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where L is obtained from Eq. [8]. V
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After tracheal intubation, the anim
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Parametric analysis The fit of the
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in the LPS-treated group is consist
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3. Worsley DF, Palevsky HI, Alavi A
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enin activity in rats chronically e
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V-20 blood without Xe C a V a (t) L
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V-22 Error in estimated diffusion l
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V-24 NMR Ventilator repetition loop
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Figure 7. The peak amplitudes (circ
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