Editing Xenon (section)

==== Imaging ====
{{main|Xenon gas MRI}}
[[gamma ray|Gamma]] emission from the [[radioisotope]] <sup>133</sup>Xe of xenon can be used to image the heart, lungs, and brain, for example, by means of [[single photon emission computed tomography]]. <sup>133</sup>Xe has also been used to measure [[blood flow]].<ref>{{cite book
| first     = Ernst
| last      = Van Der Wall
| date      = 1992
| title     = What's New in Cardiac Imaging?: SPECT, PET, and MRI
| publisher = Springer
| isbn      = 0-7923-1615-0
| url       = https://books.google.com/books?id=PypZMUhqnK8C&pg=PA41
}}</ref><ref>{{cite journal
| last        = Frank
| first       = John
| title       = Introduction to imaging: The chest
| journal     = Student BMJ
| year        = 1999
| volume      = 12
| pages       = 1–44
| url         = http://student.bmj.com/issues/04/01/education/8.php
| access-date = June 4, 2008
}}</ref><ref>{{cite web
| last         = Chandak
| first        = Puneet K.
| date         = July 20, 1995
| url          = http://brighamrad.harvard.edu/education/online/BrainSPECT/Theory/Xenon133.html
| title        = Brain SPECT: Xenon-133
| publisher    = Brigham RAD
| access-date  = June 4, 2008
| url-status   = dead
| archive-url  = https://web.archive.org/web/20120104015834/http://brighamrad.harvard.edu/education/online/BrainSPECT/Theory/Xenon133.html
| archive-date = January 4, 2012
}}</ref>

Xenon, particularly hyperpolarized <sup>129</sup>Xe, is a useful [[contrast agent]] for [[MRI|magnetic resonance imaging]] (MRI). In the gas phase, it can image cavities in a porous sample, alveoli in lungs, or the flow of gases within the lungs.<ref>{{cite journal
| last    = Albert
| first   = M. S.
| author2 = Balamore, D.
| title   = Development of hyperpolarized noble gas MRI
| journal = Nuclear Instruments and Methods in Physics Research A
| year    = 1998
| volume  = 402
| issue   = 2–3
| pages   = 441–53
| doi     = 10.1016/S0168-9002(97)00888-7
| pmid    = 11543065
| bibcode = 1998NIMPA.402..441A
}}</ref><ref>{{cite magazine
| last         = Irion
| first        = Robert
| date         = March 23, 1999
| title        = Head Full of Xenon?
| magazine     = Science News
| url          = http://sciencenow.sciencemag.org/cgi/content/full/1999/323/3
| access-date  = October 8, 2007
| archive-url  = https://web.archive.org/web/20040117194538/http://sciencenow.sciencemag.org/cgi/content/full/1999/323/3
| archive-date = January 17, 2004
}}</ref> Because xenon is [[soluble]] both in water and in hydrophobic solvents, it can image various soft living tissues.<ref>{{cite journal
| title   = Intravascular delivery of hyperpolarized 129Xenon for in vivo MRI
| journal = Applied Magnetic Resonance
| volume  = 15
| issue   = 3–4
| date    = 1998
| doi     = 10.1007/BF03162020
| pages   = 343–52
| author  = Wolber, J.
| last2   = Rowland
| first2  = I. J.
| last3   = Leach
| first3  = M. O.
| last4   = Bifone
| first4  = A.
| s2cid   = 100913538
}}</ref><ref>{{cite journal
| pmid    = 19703880
| date    = 2009
| author1 = Driehuys, B.
| author2 = Möller, H.E.
| author3 = Cleveland, Z.I.
| author4 = Pollaro, J.
| author5 = Hedlund, L.W.
| title   = Pulmonary perfusion and xenon gas exchange in rats: MR imaging with intravenous injection of hyperpolarized 129Xe
| volume  = 252
| pages   = 386–93
| doi     = 10.1148/radiol.2522081550
| pmc     = 2753782
| journal = Radiology
| issue   = 2
}}</ref><ref>{{cite journal
| pmid    = 19702286
| date    = 2009
| author  = Cleveland, Z.I.
| author2 = Möller, H.E.
| author3 = Hedlund, L.W.
| author4 = Driehuys, B.
| title   = Continuously infusing hyperpolarized 129Xe into flowing aqueous solutions using hydrophobic gas exchange membranes
| volume  = 113
| issue   = 37
| pages   = 12489–99
| doi     = 10.1021/jp9049582
| pmc     = 2747043
| journal = The Journal of Physical Chemistry
}}</ref>

Xenon-129 is used as a visualization agent in MRI scans. When a patient inhales hyperpolarized xenon-129 ventilation and gas exchange in the lungs can be imaged and quantified. Unlike xenon-133, xenon-129 is non-ionizing and is safe to be inhaled with no adverse effects.<ref>{{Cite journal
| date     = February 1, 2021
| title    = In vivo methods and applications of xenon-129 magnetic resonance
| journal  = Progress in Nuclear Magnetic Resonance Spectroscopy
| language = en
| volume   = 122
| pages    = 42–62
| doi      = 10.1016/j.pnmrs.2020.11.002
| issn     = 0079-6565
| pmc      = 7933823
| last1    = Marshall
| first1   = Helen
| last2    = Stewart
| first2   = Neil J.
| last3    = Chan
| first3   = Ho-Fung
| last4    = Rao
| first4   = Madhwesha
| last5    = Norquay
| first5   = Graham
| last6    = Wild
| first6   = Jim M.
| pmid     = 33632417
| bibcode  = 2021PNMRS.122...42M
}}</ref>