Document 10251

Hemodynamic and Metabolic Changes of Acute Cerebral Infarction Evaluated by Flow-sensitive Alternating IR
(FAIR) image and Spectroscopic Imaging(CSI), and Comparison with Dynamic Cerebral Perfusion SPECT
M.Harada,T.Okada,S.Hisao& K. Yon&, H.Nishitani,M. Uno*, amiT. Matsuda**, Department of Radiology and Neurosurgery*,
School ofMedicine,University ofTo~~~~-l8-15,Kur~oto,To~s~,
: We evaluated hemodynamic change of acute
infarction using FAIR sequence(References
12) and
comparedto the result of dynamic perfusion SPECI which was
obtainedwithin 24 hours after MRI study.In addition,diffusionweightedimages@MlW and proton spectroscopicimaging(CSI)
or MRS wert: measuredto find changesof ditlusion statusaud
metabolites.The purposesof this study are 1)To comparesemiquautitativeresultsof FAIR and cerebralperfusionSPECT,2)To
comparediffusion abnormalityof wateraud unaerobicmetabolism
appearingelevationof l&ate.
The subjectswem ten patientawho were
evaluatedby MRI within 8 hours after onset of apoplexy.The
informedconsentswereobtainedfrom patientsor patient’sfamily.
The MRI instrumentwas Signa Horizon (GE,l.ST).Immediately
after the measurement
of dMRI, FAIR and CSI wereobtainedat
the samepotion asshowingabnormalityon dMRI. The seaquence
of dMRI wasmadeon the basisof SE-EPIwith motion-probing
gradients at three axis @=lOtBs&mm2). The measurement
condition of FAIR was following; TR=2s,‘IlUOms, inversion
time(TIj=QOOms,slice thickuess=lOmm,FGV=24cm thickness
of inversion pulse =4 times thicker than slice selectivepulse,
matrix=96x%, number of excitation@?EX)=lOO. The
imageswereobtainedby PRESSunderthecondition
of TR=l2ooms, TE=135ms, Matrix=24x24, spectral data
poiuts=2400. The post-processingcontaining 2DFFK O-order
phasecorrectionand correctionof D-C offsetwas conductedon
U/GE softwaresuppliedby GE. The perfusionscintigraphyof
Tc-99m EXD including dynamic scan was measuredwithin 24
hours after MRI measmment, and the time activity curve of
dynamicscanwas calculated.The perfusionvalue of FAIR and
SPECI in theinfarct areawascalibratedsemiquautitativelyby the
imagesof FAIR showeddecreasedperfnsionin the
iufatct areaof all patients,which waswell-correlatedwith cerebral
perfusionSPEKT(Fig.1).The semiquantitativevalue of FAIR in
the infarct areahasthe good linear correlationwith that of SPFCC
(@X78, Fig.2). Howeverthe lesion/normalratios of FAIR had a
tendencyof higher vahre than those of SPEKT (slope of the
correlationline =0.54in Fig2), and this meansthat the decreaseof
perfusionobservedby FAIR may be more underestimatedthan
that by SPECT.The surroundingareaof infarctionon two patients
showedhigh intensity by FAIR, aud this areaswere depictedas
high activity by earlyphaseof dynamicSPECI(Fig.3). The time
activity curve in this area was gradually decreasedafter rapid
increaseof earlyphase,suggestinga hyper-perfusionstatusBg.4).
The remarkableelevationof lactate(lactateKr ratioAI.6) was
seenin the core of infamtion with hyper intensity by dMRI, but
lactatesignal was ciezulyobservedstill in the surroundingarea
which showedno abnorn& intensity by dMRl and low perfusion
by FAlR(Fig.S), though lactate elevation level was much
lowe@ctate/Crratio&4) thanthat in thecoreof it&r&on.
770-8503 , **GE-W%
:l)FAIR images offered the ahuost identical
informationclinically with e&y SPECTimagesof Tc-99mECD,
even though the semiquantitativeanalysisshoweda tendencyof
underestimateof low perfusion by FAIR. Furthenuore hyperperfusionwill be evaluatedby not only dynamicSPECTbut also
FAIR 2&actatesignalwill be observedin the isehemicpenumbra
by CSI, and thresholdof lactatelevel might be determinedto
discriminateviablecerebralareafrom irreversiblelesion.
:l)Kim SG, TsekosNV, Magn ResonMed 37;p4254351997
2)TsekosNV, et al. MagnResonMed 39;p564-573,199s