title: Radiation absorbed dose to the basal ganglia from dopamine transporter radioligand 18F-FPCIT.
abstract: Our previous dosimetry studies have demonstrated that for dopaminergic radiotracers, (18)F-FDOPA and (18)F-FPCIT, the urinary bladder is the critical organ. As these tracers accumulate in the basal ganglia (BG) with high affinity and long residence times, radiation dose to the BG may become significant, especially in normal control subjects. We have performed dynamic PET measurements using (18)F-FPCIT in 16 normal adult subjects to determine if in fact the BG, although not a whole organ, but a well-defined substructure, receives the highest dose. Regions of interest were drawn over left and right BG structures. Resultant time-activity curves were generated and used to determine residence times for dosimetry calculations. S-factors were computed using the MIRDOSE3 nodule model for each caudate and putamen. For (18)F-FPCIT, BG dose ranged from 0.029 to 0.069 mGy/MBq. In half of all subjects, BG dose exceeded 85% of the published critical organ (bladder) dose, and in three of those, the BG dose exceeded that for the bladder. The BG can become the dose-limiting organ in studies using dopamine transporter ligands. For some normal subjects studied with F-18 or long half-life radionuclide, the BG may exceed bladder dose and become the critical structure.
authors.affiliation: Radiation Safety Office, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: William
authors.initials: W
authors.lastname: Robeson
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: Vijay
authors.initials: V
authors.lastname: Dhawan
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: Yilong
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: David
authors.initials: D
authors.lastname: Bjelke
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: Claude
authors.initials: C
authors.lastname: Margouleff
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Chaly
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: David
authors.initials: D
authors.lastname: Eidelberg
mesh_terms: D000328:Adult; D001479:Basal Ganglia / Q000000981:diagnostic imaging*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000737:chemistry; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage; D006801:Humans; D008024:Ligands; D049268:Positron-Emission Tomography; D011829:Radiation Dosage; D011859:Radiography; D019275:Radiopharmaceuticals / Q000008:administration & dosage*; D001743:Urinary Bladder / Q000000981:diagnostic imaging* / Q000378:metabolism
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D008024:Ligands; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
references.citation: AJNR Am J Neuroradiol. 2003 Oct;24(9):1849-56
references.pmid: 14561615
references.citation: Brain Res. 2005 Apr 8;1040(1-2):169-77
references.pmid: 15804438
references.citation: Biol Psychiatry. 2006 Jan 1;59(1):57-63
references.pmid: 16112655
references.citation: Neurobiol Aging. 2008 Feb;29(2):290-302
references.pmid: 17049410
references.citation: J Nucl Med. 2003 Jun;44(6):961-6
references.pmid: 12791826
references.citation: J Nucl Med. 1996 Nov;37(11):1850-2
references.pmid: 8917191
references.citation: Radiology. 2004 Sep;232(3):867-73
references.pmid: 15215553
references.citation: J Nucl Med. 1998 Sep;39(9):1521-30
references.pmid: 9744335
references.citation: AJNR Am J Neuroradiol. 1998 Sep;19(8):1501-7
references.pmid: 9763385
references.citation: Neurology. 2004 Jul 13;63(1):66-72
references.pmid: 15249612
references.citation: J Nucl Med. 1996 Mar;37(3):538-46
references.pmid: 8772664
references.citation: Neuroimage. 2006 Oct 1;32(4):1562-75
references.pmid: 16875847
references.citation: J Nucl Med. 2006 Feb;47(2):313-9
references.pmid: 16455638
references.citation: Front Oncol. 2012 Jul 19;2:73
references.pmid: 22833841