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RefereMRM Neuroi(2011) Panchu103:2547:344in pres46:662JCBFM(2005) (2009)

David Z BaHigh-Field MR Cen

gham, Nottingham

duction onal activation matibility) and imagieliable at the same

dent. Its measuremnt effects. Quantitcant development onal QSM (fQSM)d susceptibility-chials and Methods

volunteers were scted, which alternatapping with the l

ata (TE=25ms, TR=ing order for optimce direction were cdata as a nuisanceus data were motioen performed withtime-series [8], 8th ations set to 100 [viii) These maps s

ve deconvolution aen 1 and 30 TRs) tive, convolved wits oral stability was iquent spatial filterions and their appliccessful quantificate functional suscepmed and the dipoleand maps of the pthe estimated |Δφ

ctivation-induced Bmaps additionally sve susceptibility Srity, in spite of difft of the BOLD-cht BOLD changes changes in the pareusion tative susceptibied for use in funion-induced BO

es were mapped aility of BOLD-fMic physiological tibility), limiting sequence paramehm can be appliese information hass no need for harcations.

ences: 1. de Roc63:194; 2.Whartonimage 53:515; 3

Neuroimage 54uelo et al., (20544; 5. Pfeuffer e4; 6. Hagberg et al.s; 7. Hussein et al.

23; 8.Tomasi anM 27:33; 9. Ma

Concepts MR 25NeuroImage 47:5

alla1,2, Rosa M Sanntre, Max Planck Inm, United Kingdom

aps based on BOLing (e.g. TE) parame field strength, fa

ment requires the atative susceptibiliin recent years,

) as a quantitativehanges. s canned on a 7T Pated 12s blocks of left hand, somatos=3s) with 1mm iso

mal temporal stabilcorrected by rewine regressor [6]. (ivon-corrected usingh one of the follow

order polynomial1,2]. (vii) The resu

served as inputs diralgorithm [2] with in the time doma

ith a double-gamm

improved significaing step. After initication did not intrtion of baseline suptibility maps coue-fit reconstruction

phase change estim|-map overlaid on BOLD susceptibilserved for optimizSPMs overlaid onferences between T

hange in blood susin modulus, phaseenchyma (1o predi

ility mapping nctional imaging OLD susceptibiat 7T. This offers

MRI related directlyquantity (magnthe dependence

eters. The propod on any time-sers been collected, rdware or acquisi

chefort et al., (20n and Bowtell, (203. Schweser et 4:2789; 4. Sanch10) J Neurophyet al., (2002) M., (2011) Neuroima., (2007) Appl. Opd Caparelli, (20arques and BowB:65; 10. Feng et

540

Functionalnchez-Panchuelo2, Institute for Biologm, 3Physiology of C

Neuroimaging a

LD-fMRI provide meters. As an attest T2*-mapping caacquisition of twoty mapping (QSMpartly due to the

e approach for BO

Philips scanner duf task/stimulation wsensory stimulus: 6otropic resolution lity and statistical

nding the phase in v) Spatial unwrap

g 3dAllineate (AFNwing methods: hom background field ulting phase-imagrectly for the calcua maximum of 15

ain before uncorrema HRF and filtere

antly by correctingtial global filteringroduce temporal m

usceptibility maps.uld be produced wn method was usemated using forwathe filtered phase ity changes are no

zation of the reconn the negative QST2* (Fig.1) and neceptibility, but thie and susceptibiliticted by [10]) and

was and ility the

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on osed ries, and tion

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al., hez-ysiol RM age,

ptics 007) wtell t al.,

l QuantitativeSam Wharton2, Gi

gical Cybernetics, Cognitive Processeand MR-Physics, U

qualitative topologmpt to relate BOLan serve as an alte

o echoes per repetiM) uses phase inf

emergence of adOLD-fMRI, and p

uring a multi-taskwith 18s blocks of60 Hz vibrotactile[4] spanning eithepower. (i) Phase k-space [5]. (iii) G

pping was performNI), and the resultimodyne Gaussian w

removal, SHARPges, except for the ulation of phase-SP5 iterations. Filterected activation mad in time with the

g for global intensg in the time domamodulation. Remo The relative phas

with this method. Fed. Filtered phase iard field calculatio

image. The measuot exclusively encnstruction process

SM. Comparison egative susceptibils negative changety were observed to quantify suscep

e Susceptibilityisela E Hagberg3, KTuebingen, Germaes, Max Planck InsUniversity of Tuebi

gies of task-relateLD changes to an ernative to T2*-weition, is sensitive formation from Mdvanced backgrouproposes a multi-s

k fMRI experimenf rest; visual stimu

e stimulation applier the visual or themaps were maske

Global temporal phmed using a fast 3ing correction matwith kernel size 12

P with a threshold orelative phase filt

PMs or for the QSed modulus and phaps (p<10-10) weresame parameters a

sity variations. Thain, all of the appving slow phase m

se filtering only retFigures 1-5 presentimages revealed fion [9], by replacinured |Δφ|-map is pcoded in the T2*-s. Fig.4 presents aof activation pattlity contrast (Fig.4e coexists with pos

around veins. Filtptibility changes w

y Mapping (fQKlaus Scheffler1,4,any, 2Sir Peter Mastitute for Biologicingen, Tuebingen,

ed modulus intensiabsolute quantity

eighted imaging. Hto unwanted dyna

MR images to calund field removal step filtering algor

nt. Paradigm: A vulus: a flickering ied to the fingertipe sensorimotor cored using binarised hase variations we

3D algorithm [7], trices were then ap2mm, relative phaof 0.1 and a kernetered data-sets, we

SM calculations. Suhase images and sue calculated with as the functional d

his was essential flied spatial filters

modulations of extetained informationted below result fr

fine structural braing susceptibility wpresented in Fig.3-weighted image ian SPM derived fterns in modulus 4). As expected, susitive modulation tering out this vas

with better spatial c

QSM) , Sue T Francis2, a

ansfield Magnetic Rcal Cybernetics, TuGermany

ity changes whichand to render the

However, T2* is anamic effects and tlculate local tissu

methods [1-3]. Trithm for the calc

visual, motor or scheckerboard ring

ps of the left handrtex. Analysis: Promodulus images. ere corrected by uand was followed

pplied to the phasease filtering by comel size of 2mm [3] ere then divided busceptibility mapsusceptibility mapsFSL. The GLM i

data. Pre-whitening

for efficient reducwere successful i

ternal origin from n about dynamic cfrom an fMRI-datain contrast (Fig.2).with the modulus . Significant differintensity. The comfrom the magnitud(Fig.1) and QSM

usceptibility decreain neighbouring vscular contributioncorrelation to neura

and Richard W BowResonance Centre

Tuebingen, German

h depend on physiocomparison of BO

n MR-specific parto static, but non-lue susceptibility. IThis study introduculation of maps s

somatosensory blog on a grey backgrd. Protocol: Zoomocessing steps wer(ii) Global intensi

using the phase at td by temporal unw

e data. (vi) High-pamplex division wior dipole-fit with

by γB0TE×10-6 to ys (QSM) were calcs were smoothed (bincluded the blockg of the data was n

ction of the backgrin removing low-fthe region of inte

changes in phase aaset where a finge. Activation induc%-change, were i

rences between Fimparison of estimade data along wit

M data (Fig.4-5) rases (-Δχ) up to 7%

voxels (Fig.5). Alsn will be necessaral activity.

wtell2 e, University of ny, 4Department of

ological (magneticOLD-fMRI studiesrameter and is fieldlocal susceptibilityIt has experienceduces time-resolvedshowing activation

ock-paradigm waround, motor tasked multi-slice GE

re performed in thety variations alongthe origin of the kwrapping. (v) Theass spatial filteringith the first volumemaximum numbe

yield field maps inculated by using anband-pass filteringk-paradigm and itnot performed.

round fields in thefrequency intensityerest was importanand, therefore, onlyer tapping task waced Δφ (%-changeinvestigated. Fig.2igs.2 and 3 suggesated and measuredth the positive andreveals remarkable% on activation ao, as expected, thery for detection o

f

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e y t y s ) 2 t d d e s e f

325Proc. Intl. Soc. Mag. Reson. Med. 20 (2012)