title: Simultaneous evaluation of vascular morphology, blood volume and transvascular permeability using SPION-based, dual-contrast MRI: imaging optimization and feasibility test.
abstract: Exploiting ultrashort-T(E) (UTE) MRI, T1-weighted positive contrast can be obtained from superparamagnetic iron oxide nanoparticles (SPIONs), which are widely used as a robust T2-weighted, negative contrast agent on conventional MR images. Our study was designed (a) to optimize the dual-contrast MRI method using SPIONs and (b) to validate the feasibility of simultaneously evaluating the vascular morphology, blood volume and transvascular permeability using the dual-contrast effect of SPIONs. All studies were conducted using 3 T MRI. According to numerical simulation, 0.15 mM was the optimal blood SPION concentration for visualizing the positive contrast effect using UTE MRI (T(E) = 0.09 ms), and a flip angle of 40° could provide sufficient SPION-induced enhancement and acceptable measurement noise for UTE MR angiography. A pharmacokinetic study showed that this concentration can be steadily maintained from 30 to 360 min after the injection of 29 mg/kg of SPIONs. An in vivo study using these settings displayed image quality and CNR of SPION-enhanced UTE MR angiography (image quality score 3.5; CNR 146) comparable to those of the conventional, Gd-enhanced method (image quality score 3.8; CNR 148) (p > 0.05). Using dual-contrast MR images obtained from SPION-enhanced UTE and conventional spin- and gradient-echo methods, the transvascular permeability (water exchange index 1.76-1.77), cerebral blood volume (2.58-2.60%) and vessel caliber index (3.06-3.10) could be consistently quantified (coefficient of variation less than 9.6%; Bland-Altman 95% limits of agreement 0.886-1.111) and were similar to the literature values. Therefore, using the optimized setting of combined SPION-based MRI techniques, the vascular morphology, blood volume and transvascular permeability can be comprehensively evaluated during a single session of MR examination.
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.|Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors: Heon-Ju
authors: HJ
authors: Kwon
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.
authors: Woo Hyun
authors: WH
authors: Shim
authors: Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South Korea.
authors: Gyunggoo
authors: G
authors: Cho
authors: Ulsan National Institute of Science and Technology, Ulsan, South Korea.
authors: Hyung Joon
authors: HJ
authors: Cho
authors: Ulsan National Institute of Science and Technology, Ulsan, South Korea.
authors: Hoe Su
authors: HS
authors: Jung
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.|Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South Korea.
authors: Chang Kyung
authors: CK
authors: Lee
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.|Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South Korea.
authors: Yong Seok
authors: YS
authors: Lee
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.|Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South Korea.
authors: Jin Hee
authors: JH
authors: Baek
authors: Philips Healthcare, Seoul, South Korea.
authors: Eun Ju
authors: EJ
authors: Kim
authors: Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South Korea.
authors: Ji-Yeon
authors: JY
authors: Suh
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.
authors: Yu Sub
authors: YS
authors: Sung
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.
authors: Dong-Cheol
authors: DC
authors: Woo
authors: Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA.
authors: Young Ro
authors: YR
authors: Kim
authors: Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Asan Institute for Life Sciences, Seoul, South Korea.|Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South Korea.
authors: Jeong Kon
authors: JK
authors: Kim
mesh_terms: D000818:Animals; D001810:Blood Volume / Q000502:physiology*; D001811:Blood Volume Determination / Q000379:methods; D002199:Capillary Permeability / Q000502:physiology*; D002536:Cerebral Arteries / Q000033:anatomy & histology* / Q000502:physiology*; D003198:Computer Simulation; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics; D003911:Dextrans / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005240:Feasibility Studies; D007089:Image Enhancement / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000008:administration & dosage; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008955:Models, Cardiovascular; D009929:Organ Size / Q000502:physiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; C097921:ferumoxtran-10
keywords: MR angiography; blood volume; dual contrast; superparamagnetic iron oxide nanoparticles; ultrashort TE imaging; water exchange index