title: BOLD MRI of human tumor oxygenation during carbogen breathing.
abstract: An MRI method is described for demonstrating improved oxygenation of human tumors and normal tissues during carbogen inhalation (95% O2, 5% CO2). T2*-weighted gradient-echo imaging was performed before, during, and after carbogen breathing in 47 tumor patients and 13 male volunteers. Analysis of artifacts and signal intensity was performed. Thirty-six successful tumor examinations were obtained. Twenty showed significant whole-tumor signal increases (mean 21.0%, range 6.5-82.4%), and one decreased (-26.5 +/- 8.0%). Patterns of signal change were heterogeneous in responding tumors. Five of 13 normal prostate glands (four volunteers and nine patients with nonprostatic tumors) showed significant enhancement (mean 11.4%, range 8.4-14.0%). An increase in brain signal was seen in 11 of 13 assessable patients (mean 8.0 +/- 3.7%, range 5.0-11.7%). T2*-weighted tumor MRI during carbogen breathing is possible in humans. High failure rates occurred due to respiratory distress. Significant enhancement was seen in 56%, suggesting improved tissue oxygenation and blood flow, which could identify these patients as more likely to benefit from carbogen radiosensitization.
authors.affiliation: Paul Strickland Scanner Centre, Mount Vernon Hospital, Northwood, Middlesex, United Kingdom. taylor@graylab.ac.uk
authors.forename: N J
authors.initials: NJ
authors.lastname: Taylor
authors.forename: H
authors.initials: H
authors.lastname: Baddeley
authors.forename: K A
authors.initials: KA
authors.lastname: Goodchild
authors.forename: M E
authors.initials: ME
authors.lastname: Powell
authors.forename: M
authors.initials: M
authors.lastname: Thoumine
authors.forename: L A
authors.initials: LA
authors.lastname: Culver
authors.forename: J J
authors.initials: JJ
authors.lastname: Stirling
authors.forename: M I
authors.initials: MI
authors.lastname: Saunders
authors.forename: P J
authors.initials: PJ
authors.lastname: Hoskin
authors.forename: H
authors.initials: H
authors.lastname: Phillips
authors.forename: A R
authors.initials: AR
authors.lastname: Padhani
authors.forename: J R
authors.initials: JR
authors.lastname: Griffiths
mesh_terms: D000368:Aged; D016477:Artifacts; D001921:Brain / Q000033:anatomy & histology; D002245:Carbon Dioxide; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology*; D010100:Oxygen; D011446:Prospective Studies; D011467:Prostate / Q000033:anatomy & histology; D011838:Radiation-Sensitizing Agents
chemical_list: D011838:Radiation-Sensitizing Agents; D002245:Carbon Dioxide; C011700:carbogen; D010100:Oxygen