Functional imaging with MR T1 contrast: a feasibility study with blood-pool contrast agent.
The aim of this study was to prove the concept of using a long intravenous half-life blood-pool T1 contrast agent as a new functional imaging method. For each of ten healthy subjects, two dynamic magnetic resonance (MR) protocols were carried out: (1) a reference run with a typical T2* echo-planar imaging (EPI) sequence based on the blood oxygenation level-dependent (BOLD) effect and (2) a run with a T1-sensitive three-dimensional (3D) gradient-echo (GRE) sequence using cerebral blood volume (CBV) contrast after intravenous administration of a contrast agent containing a chelate of gadolinium diethylene-triamine-pentaacetate with a phosphono-oxymethyl substituent. All sequences were performed during the execution of a block-type finger-tapping paradigm. SPM5 software was used for statistical analysis. For both runs maximum activations (peak Z-score = 5.5, cluster size 3,449 voxels) were localized in the left postcentral gyrus. Visual inspection of respective signal amplitudes suggests the T1 contrast to be substantially smaller than EPI (0.5% vs 1%). A new functional imaging method with potentially smaller image artefacts due to the nature of CBV contrast and characteristics of the T1 sequence was proposed and verified.
Majos
Agata
A
Radiology Department, Medical University of Lodz, Lodz, Poland. egnys9@interia.pl
Bogorodzki
Piotr
P
Piatkowska-Janko
Ewa
E
Wolak
Tomasz
T
Kurjata
Robert
R
Stefańczyk
Ludomir
L
D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology; D002614:Chelating Agents / Q000494:pharmacology; D003287:Contrast Media / Q000494:pharmacology*; D003952:Diagnostic Imaging / Q000379:methods*; D017352:Echo-Planar Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D013997:Time Factors
D002614:Chelating Agents; D003287:Contrast Media