title: Cerebral blood volume MRI with intravascular superparamagnetic iron oxide nanoparticles.
abstract: The cerebral blood volume (CBV) is a crucial physiological indicator of tissue viability and vascular reactivity. Thus, noninvasive CBV mapping has been of great interest. For this, ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles, including monocrystalline iron oxide nanoparticles, can be used as long-half-life, intravascular susceptibility agents of CBV MRI measurements. Moreover, CBV-weighted functional MRI (fMRI) with USPIO nanoparticles provides enhanced sensitivity, reduced large vessel contribution and improved spatial specificity relative to conventional blood oxygenation level-dependent fMRI, and measures a single physiological parameter that is easily interpretable. We review the physiochemical and magnetic properties, and pharmacokinetics, of USPIO nanoparticles in brief. We then extensively discuss quantifications of baseline CBV, vessel size index and functional CBV change. We also provide reviews of dose-dependent sensitivity, vascular filter function, specificity, characteristics and impulse response function of CBV fMRI. Examples of CBV fMRI specificity at the laminar and columnar resolution are provided. Finally, we briefly review the application of CBV measurements to functional and pharmacological studies in animals. Overall, the use of USPIO nanoparticles can determine baseline CBV and its changes induced by functional activity and pharmacological interventions.
authors.affiliation: Neuroimaging Laboratory, Department of Radiology, University of Pittsburgh, PA, USA. kimsg@pitt.edu
authors.forename: Seong-Gi
authors.initials: SG
authors.lastname: Kim
authors.forename: Noam
authors.initials: N
authors.lastname: Harel
authors.forename: Tao
authors.initials: T
authors.lastname: Jin
authors.forename: Tae
authors.initials: T
authors.lastname: Kim
authors.forename: Phil
authors.initials: P
authors.lastname: Lee
authors.forename: Fuqiang
authors.initials: F
authors.lastname: Zhao
mesh_terms: D000818:Animals; D001160:Arterioles / Q000033:anatomy & histology; D001810:Blood Volume; D001921:Brain / Q000098:blood supply / Q000378:metabolism; D002545:Brain Ischemia / Q000473:pathology; D002536:Cerebral Arteries / Q000033:anatomy & histology; D002560:Cerebrovascular Circulation; D003287:Contrast Media / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D003911:Dextrans / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D006207:Half-Life; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000008:administration & dosage / Q000737:chemistry; D008833:Microcirculation; D009043:Motor Activity; D009488:Neurosciences / Q000379:methods; D010100:Oxygen / Q000097:blood*; D012680:Sensitivity and Specificity; D014699:Venules / Q000033:anatomy & histology
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; C097921:ferumoxtran-10; D010100:Oxygen