Document Detail

Magnetisation transfer effects of Q2TIPS pulses in ASL.
MedLine Citation:
PMID:  22203428     Owner:  NLM     Status:  MEDLINE    
OBJECT: In pulsed arterial spin labelling (ASL), Q2TIPS saturation pulses are used to actively control the temporal width of the labelled bolus. However, these Q2TIPS pulses also induce magnetisation transfer (MT) effects in the adjacent tissue. In this work, we investigated how Q2TIPS-related MT alters tissue signal in pulsed ASL and, consequently, CBF quantification.
MATERIALS AND METHODS: Seven volunteers were studied at 3 tesla using a multi-TI FAIR sequence and 3D-GRASE readout with background suppression. Q2TIPS pulses were used and the spacing between RF pulses was varied to modulate MT effects. Computer simulations were designed to mimic in-vivo signals at multiple TI values.
RESULTS: Q2TIPS-associated MT was found to reduce tissue T1 and M0 values by up to 42 and 50% respectively; leading to a reduction of up to 40% in the effectiveness of background suppression and, therefore, increased sensitivity to motion for the longest TI values. In addition, greater MT effects were associated with reduced grey matter CBF estimates of up to 15%.
CONCLUSIONS: The MT effect associated with the Q2TIPS pulse train has a significant effect on tissue signal. It is recommended that MT effects are characterised and both background suppression and Q2TIPS schemes are accordingly optimised to reduce the effects of MT on accuracy and precision of CBF estimation.
Enrico De Vita; Matthias Günther; Xavier Golay; David L Thomas
Related Documents :
22846278 - Vibrational frequency response to impact loading of skull models.
18246148 - Continuous wave 935 nm nd:cngg laser at watt-level power.
20720988 - Highly efficient yb:yag channel waveguide laser written with a femtosecond-laser.
20967108 - Widely tunable mid-ir difference-frequency generation based on fiber lasers.
21405168 - The isotropic remnant of the co(2) near-fully depolarized raman 2ν(3) overtone.
19253978 - Mutarotation in d-fructose melt monitored by dielectric spectroscopy.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2011-12-28
Journal Detail:
Title:  Magma (New York, N.Y.)     Volume:  25     ISSN:  1352-8661     ISO Abbreviation:  MAGMA     Publication Date:  2012 Apr 
Date Detail:
Created Date:  2012-03-27     Completed Date:  2012-07-23     Revised Date:  2014-01-20    
Medline Journal Info:
Nlm Unique ID:  9310752     Medline TA:  MAGMA     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  113-26     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Arteries / physiology*
Brain / blood supply*,  physiology
Cerebrovascular Circulation / physiology*
Computer Simulation
Magnetic Resonance Imaging / methods*
Perfusion Imaging / methods
Regional Blood Flow
Spin Labels*
Grant Support
//Department of Health
Reg. No./Substance:
0/Spin Labels

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Prevalence and Correlates of Sustained Hypertension in Adolescents of Rural Wardha, Central India.
Next Document:  Iatrogenic Cushing syndrome due to nasal steroid drops.