title: DUSTER: dynamic contrast enhance up-sampled temporal resolution analysis method.
abstract: Dynamic contrast enhanced (DCE) MRI using Tofts' model for estimating vascular permeability is widely accepted, yet inter-tissue differences in bolus arrival time (BAT) are generally ignored. In this work we propose a method, incorporating the BAT in the analysis, demonstrating its applicability and advantages in healthy subjects and patients. A method for DCE Up Sampled TEmporal Resolution (DUSTER) analysis is proposed which includes: baseline T1 map using DESPOT1 analyzed with flip angle (FA) correction; preprocessing; raw-signal-to-T1-to-concentration time curves (CTC) conversion; automatic arterial input function (AIF) extraction at temporal super-resolution; model fitting with model selection while incorporating BAT in the pharmacokinetic (PK) model, and fits contrast agent CTC while using exhaustive search in the BAT dimension in super-resolution. The method was applied to simulated data and to human data from 17 healthy subjects, six patients with glioblastoma, and two patients following stroke. BAT values were compared to time-to-peak (TTP) values extracted from dynamic susceptibility contrast imaging. Results show that the method improved the AIF estimation and allowed extraction of the BAT with a resolution of 0.8 s. In simulations, lower mean relative errors were detected for all PK parameters extracted using DUSTER compared to analysis without BAT correction (vp:5% vs. 20%, Ktrans: 9% vs. 24% and Kep: 8% vs. 17%, respectively), and BAT estimates demonstrated high correlations (r = 0.94, p < 1e− 10) with true values. In real data, high correlations between BAT values were detected when extracted from data acquired with high temporal resolution (2 s) and sub-sampled standard resolution data (6 s) (mean r = 0.85,p < 1e− 10). BAT and TTP values were significantly correlated in the different brain regions in healthy subjects (mean r = 0.72,p = < 1e− 3), as were voxel-wise comparisons in patients (mean r = 0.89, p < 1e− 10). In conclusion, incorporating BAT in DCE analysis improves estimation accuracy for the AIF and the PK parameters while providing an additional clinically important parameter.
authors.affiliation: The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan.
authors.forename: Gilad
authors.initials: G
authors.lastname: Liberman
authors.affiliation: Mathematics Department, Bar-Ilan University, Ramat-Gan.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Louzoun
authors.affiliation: The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Moran
authors.initials: M
authors.lastname: Artzi
authors.affiliation: The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; School of Electrical Engineering, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Guy
authors.initials: G
authors.lastname: Nadav
authors.affiliation: Department of Neurology, Henry Ford Health System, MI, USA; Department of Physics, Oakland University, MI, USA; Department of Neurology, Wayne State University Medical School, MI, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Ewing
authors.affiliation: The Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel. Electronic address: dafnab@tlvmc.gov.il.
authors.forename: Dafna
authors.initials: D
authors.lastname: Ben Bashat
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D002199:Capillary Permeability; D003198:Computer Simulation; D003287:Contrast Media / Q000493:pharmacokinetics*; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging; D064368:Healthy Volunteers; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008962:Models, Theoretical; D020521:Stroke / Q000000981:diagnostic imaging; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Bolus arrival time; DUSTER; Dynamic contrast enhancement; Temporal super resolution