Supported by NIH HL081171, NIH HL080203

<ol>
	<li>Bolar, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+regional+pulmonary+blood+flow+using+ASL-FAIRER.">Quantification of regional pulmonary blood flow using ASL-FAIRER.</a> Magn Reson Med. 55, 1308-1317 (2006).</li><li>Henderson, A. C., Prisk, G. K., Levin, D. L., Hopkins, S. R., Buxton, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterizing+pulmonary+blood+flow+distribution+measured+using+arterial+spin+labeling.">Characterizing pulmonary blood flow distribution measured using arterial spin labeling.</a> NMR Biomed. 22, 1025-1035 (2009).</li><li>Theilmann, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+MRI+measurement+of+lung+density+must+account+for+the+change+in+T(2)+(*)+with+lung+inflation.">Quantitative MRI measurement of lung density must account for the change in T(2) (*) with lung inflation.</a> J Magn Reson Imaging. 30, 527-534 (2009).</li><li>Hopkins, S. R., Garg, J., Bolar, D. S., Balouch, J., Levin, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+blood+flow+heterogeneity+during+hypoxia+and+high-altitude+pulmonary+edema.">Pulmonary blood flow heterogeneity during hypoxia and high-altitude pulmonary edema.</a> Am J Respir Crit Care Med. 171, 83-87 (2005).</li><li>Miller, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standardisation+of+spirometry.">Standardisation of spirometry.</a> Eur Respir J. 26, 319-338 (2005).</li><li>Hopkins, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vertical+gradients+in+regional+lung+density+and+perfusion+in+the+supine+human+lung:+the+Slinky+effect.">Vertical gradients in regional lung density and perfusion in the supine human lung: the Slinky effect.</a> J Appl Physiol. 103, 240-248 (2007).</li><li>Arai, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypoxic+pulmonary+vasoconstriction+does+not+contribute+to+pulmonary+blood+flow+heterogeneity+in+normoxia+in+normal+supine+humans.">Hypoxic pulmonary vasoconstriction does not contribute to pulmonary blood flow heterogeneity in normoxia in normal supine humans.</a> J Appl Physiol. 106, 1057-1064 (2009).</li><li>Dawson, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+pulmonary+vasomotion+in+physiology+of+the+lung.">Role of pulmonary vasomotion in physiology of the lung.</a> Physiol Rev. 64, 544-616 (1984).</li><li>Prisk, G. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+perfusion+in+the+prone+and+supine+postures+in+the+normal+human+lung.">Pulmonary perfusion in the prone and supine postures in the normal human lung.</a> J Appl Physiol. 103, 883-894 (2007).</li><li>Henderson, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Steep+head-down+tilt+has+persisting+effects+on+the+distribution+of+pulmonary+blood+flow.">Steep head-down tilt has persisting effects on the distribution of pulmonary blood flow.</a> J Appl Physiol. 101, 583-589 (2006).</li><li>Levin, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+age+on+pulmonary+perfusion+heterogeneity+measured+by+magnetic+resonance+imaging.">Effects of age on pulmonary perfusion heterogeneity measured by magnetic resonance imaging.</a> J Appl Physiol. 102, 2064-2070 (2007).</li><li>Wasserman, K. H., Sue, D., Casaburi, R., Whipp, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calculations,+Fomulae,+and+Examples+(Appendix+C).">Calculations, Fomulae, and Examples (Appendix C).</a> Principles of Exercise Testing and Interpretation. , (1999).</li></ol>

No conflicts of interest declared.

This method enables measurement of the effects of inspired oxygen concentration on the spatial distribution of pulmonary 
blood flow using basic physiological techniques in the MR scan environment. The use of physiological techniques in combination with 
quantitative proton imaging of the lung is relatively easily implemented.
To ensure a good quality test, the most important step is training the subject to breath-hold at the correct lung volume 
and in synchrony with the imaging sequence. Si...

<table border="1">

	<tbody>
 <tr>
 	<th>Equipment</th>
 <th>Company</th>
 <th>model</th>
 </tr>
 <tr>
 	<td>MRI</td>
 <td>GE</td>
 <td>1.5 T GE HDx EXICITE twinspeed scanner</td>
 
 </tr>
 <tr>
 	<td>Metabolic cart</td>
 <td>ParvoMedics</td>
 <td>TrueOne 2400</td>
 
 </tr>
 <tr>
 	<td>Pulse Oximeter</td>
 <td>Nonin</td>
 <td>7500 FO</td>
 
 </tr>
 <tr>
 	<td>Spirometer</td>
 <td>Medical Technologies Andover</td>
 <td>EasyOne diagonostic Spirometer</td>
 
 </tr>
 <tr>
 	<td>Mask</td>
 <td>Hans &amp; Rudolph

</td>
 <td>7400 series Oro-Nasal Mask, Small, Medium, and Large</td>
 
 </tr>
 <tr>
 	<td>Valve</td>
 <td>Hans &amp; Rudolph

</td>
 <td>Two-way non-rebreathing valves T-Shape&trade; configuration, 2600 Medium. 2700 Large</td>
 
 </tr>
 <tr>
 	<td>Head Set</td>
 <td>Hans &amp; Rudolph

</td>
 <td>Head cap (Adult size), strap &amp; Locking Clips.</td>
 
 </tr>
 <tr>
 	<td>Pneumatic directional control valve and controller</td>
 <td>Hans &amp; Rudolph</td>
 <td>Single Piston Sliding-Type&trade; valve and controller 4285A </td>
 
 </tr>
 <tr>
 	<td>Non-Diffusing gas collection bag </td>
 <td>Hans &amp; Rudolph

</td>
 <td>6100 (100 liters).

</td>
 </tr>
 <tr>
 	<td>Tube</td>
 <td>VacuMed</td>
 <td>Clean-Bor Tubing 108&#x201D;, 1-3/8&#x201D; OD fittings</td>
 </tr>
 <tr>
 	<td>Phantoms</td>
 <td>Mentor</td>
 <td>Brest Implant Round, 250cc</td>
 </tr>
 <tr>
 	<td>matlab</td>
 <td>The MathWorks</td>
 <td>&nbsp;</td>
 </tr>
 
 </tbody>
</table>

magnetic resonance imaging quantification of pulmonary perfusion using calibrated arterial spin labeling

This demonstrates a MR imaging method to measure the spatial distribution of pulmonary blood flow in healthy subjects 
during normoxia (inspired O2, fraction (FIO2) = 0.21) hypoxia (FIO2 = 0.125), and hyperoxia 
(FIO2 = 1.00). In addition, the physiological responses of the subject are monitored in the MR scan environment. MR images 
were obtained on a 1.5 T GE MRI scanner during a breath hold from a sagittal slice in the right lung at functional residual capacity. An arterial 
spin labeling sequence (ASL-FAIRER) was used to measure the spatial distribution of pulmonary blood flow 1,2 and a multi-echo fast 
gradient echo (mGRE) sequence 3 was used to quantify the regional proton (i.e. H2O) density, allowing the quantification 
of density-normalized perfusion for each voxel (milliliters blood per minute per gram lung tissue). 
With a pneumatic switching valve and facemask equipped with a 2-way non-rebreathing valve, different oxygen concentrations 
were introduced to the subject in the MR scanner through the inspired gas tubing. A metabolic cart collected expiratory gas via expiratory tubing. Mixed expiratory O2 and CO2 concentrations, oxygen consumption, carbon dioxide production, respiratory exchange ratio, 
respiratory frequency and tidal volume were measured. Heart rate and oxygen saturation were monitored using pulse-oximetry. 
Data obtained from a normal subject showed that, as expected, heart rate was higher in hypoxia (60 bpm) than during normoxia (51) or hyperoxia (50) and the arterial oxygen saturation (SpO2) was reduced during hypoxia to 86%. Mean ventilation was 8.31 L/min BTPS during hypoxia, 7.04 L/min during normoxia, and 6.64 L/min during hyperoxia. Tidal volume was 0.76 L during hypoxia, 0.69 L during normoxia, and 0.67 L during hyperoxia. 
Representative quantified ASL data showed that the mean density normalized perfusion was 8.86 ml/min/g during hypoxia, 8.26 ml/min/g during normoxia and 8.46 ml/min/g during hyperoxia, respectively. In this subject, the relative dispersion4, an index of global heterogeneity, was increased in hypoxia (1.07 during hypoxia, 0.85 during normoxia, and 0.87 during hyperoxia) while the fractal dimension (Ds), another index of heterogeneity reflecting vascular branching structure, was unchanged (1.24 during hypoxia, 1.26 during normoxia, and 1.26 during hyperoxia). 
Overview. This protocol will demonstrate the acquisition of data to measure the distribution of pulmonary perfusion noninvasively under conditions of normoxia, hypoxia, and hyperoxia using a magnetic resonance imaging technique known as arterial spin labeling (ASL). 
Rationale: Measurement of pulmonary blood flow and lung proton density using MR technique offers high spatial resolution images which can be quantified and the ability to perform repeated measurements under several different physiological conditions. In human studies, PET, SPECT, and CT are commonly used as the alternative techniques. However, these techniques involve exposure to ionizing radiation, and thus are not suitable for repeated measurements in human subjects.

Watch this Scientific Journal Video about Magnetic Resonance Imaging Quantification of Pulmonary Perfusion using Calibrated Arterial Spin Labeling at JoVE.com

Magnetic Resonance Imaging Quantification of Pulmonary Perfusion using Calibrated Arterial Spin Labeling

A MR imaging method to study the distribution of pulmonary blood flow under a variety of physiological conditions, in this case exposure to three different inspired oxygen concentrations: hypoxia, normoxia, and hyperoxia, is described. This technique utilizes human pulmonary physiology research techniques in an MR scanning environment.

This demonstrates a MR imaging method to measure the spatial distribution of pulmonary blood flow in healthy subjects 
during normoxia (inspired O2, ...

magnetic-resonance-imaging-quantification-pulmonary-perfusion-using

Research

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13.4K Views.  University of California San Diego - UCSD. A MR imaging method to study the distribution of pulmonary blood flow under a variety of physiological conditions, in this case exposure to three different inspired oxygen concentrations: hypoxia, normoxia, and hyperoxia, is described. This technique utilizes human pulmonary physiology research techniques in an MR scanning environment.