INTRODUCTION THEORY
1
1 Bi INTR challspecdefic have In th we th THE DRAs trans data form in Fig (a) ve in to strea (a)). MET healt (Mag coil a gap) (prod angle calib radia delay Altho the r PE re RES recon (a,b) Carte same LV/earrow inten seen show inten wher are f reduDISalong Gibb proje stres is noREFE et al., et al. ProBehzad Sharif 1 , R omedical Imaging RODUCTION enging dynamic ifically the so-ca cits [1-3], and arbeen many atte is work, we dem herefore propos EORY In Cartes due to an insitions [3,4]. Ho transform is the as FT (instead s g. 1 using a num ersus 108 projec the blood-pool/ aking artifacts in THODS To inv thy human vol gnetom Verio, Sarray. Two first- using a single-s duct) sequence e = 12; TR/TE = rating parallel im al) with 36-40 re y correction an ough the readou radial scheme (≈ esol. ≈2.6 mm) a SULTS F nstruction resul and human (esian/radial ima e phase of the arly-myocardial ws in panels (a nsities that werin the figurew DRAs (arronsities) in the reas the project free of dark rim ced contrast-to- CUSSION Re g the PE directio s ringing, a maj ection imaging ( s imaging. Howt sufficient and ERENCES [1] W , JCMR 2009;11(17 MRM 2006;55:11 jection Imagin Rohan Dharmakum g Research Institut N Despite signifi c imaging applic alled subendoca e especially limiempts at minimmonstrate that p se radial k-space sian MP MR, Gi herent propertowever, in proje e Radon transfoshows streaking merical phantom ctions in Panel (b /myocardium bo n (b) do not resvestigate the vaunteers (N=4; iemens AG Healpass MP scans hot radial (custo (common para2.4/1.4 ms; TI maging (TGRAPP eadouts. The cu nd a 4-fold intut resolution for ≈1.8 mm vs. ≈2.nd radial scans igure 2 sho ts for represent c,d) scans. Eac ages correspon e contrast upta enhancemen ) and (c) point e considered D, Cartesian ima ws pointing subendocardia tion reconstruct ms (although wi-noise ratio). cently, a major on) and thereby or contributing radial trajectori ever, to match t constrained (e.g ilke NM, et al., JM 7). [5] Kak and Sla50-6. [8] Plein S, e ng of Myocard mar 1 , Chrisandra S e, Cedars-Sinai M Institute, Cedarcant technical a ations [1,2]. Cu rdial dark-rim a ting since they c zing DRAs in spprojection imagsampling as a p bbs ringing alon y of the Fourie ection imaging rm [5], which do artifacts if high m simulation witb)). Fig. 1(c) shoorder. It can be s ult in a “signal idity of this obs IRB approved) thcare, Erlangen (SR-prepared FL omized) pulse smeters: FOV re= 100 ms). Bot PA for Cartesian ustomized radia erleaving schem r the Cartesian s 2 mm), the ove(isotropic ≈2.2 m ows the tative dog h pair of d to the ake (late- nt). The to hypo- RAs. As is ages (a,c) to hypo- l regions tions (b,d) th slightly approach for eli reducing Gibbs factor to DRAses). The presen he high resoluti g., using compreMRI 1999;10:676-6ney, Principles of et al., MRM 2007;5 F he co en D dial Perfusion Shufelt 2 , Troy LaB Medical Center, ans-Sinai Medical C advances over t rrent clinical M rtifact (DRA) [2- can reduce the s ecific protocols, ing of first-pass preferred acquisng the phase-en er transform (F(radial k-space oes not exhibit tly undersampleh realistic intenws a 1D cut alon seen that, unlike dip” (which causervation in-vivo were imaged n, Germany) wit LASH) were perequence followe ad = 270-300 m h scans were aand self-calibral sequence inco me combined w scan was higher rall resolution o mm in-plane) we minating the DR ringing [8,9]. In We conclude ted results werons achieved in ssed sensing) pr 85. [2] Gerber BL, Computerized Tom 58:777-85. [9] Ota igure 2. Repre ealthy canine m orresponds to nhancement pha DRAs are not see n: Minimizing ounty 2 , Louise Th d University of Ca Center, Los Angeles he past decade P MR methods 4]. DRAs are cau sensitivity/specif yet it remains a myocardial perf ition scheme for code (PE) direct T) at sharp sign acquisition), the he Gibbs ringing d). This fact is de sity values (108 ng the PE directi e the Gibbs ringi ses noticeable D o, healthy canine on a clinical h a 32 channel c formed at rest ( ed by a single-sh mm; BW ≈ 800 ccelerated using ting non-Cartesi orporated adapt with KWIC proc than the base r of Cartesian (anis ere matched to w RAs in first-pass n this work, we that an alternat e limited to rest advanced Carte rojection reconst et al., JCMR 2008 mographic Imaging zo R, et al., MRM esentative in-vivo model; (c,d) hea the same pha ase). The arrow en in the projectio the Subendoc homson 2 , Noel Bai alifornia Los Ange s, California, Unie, myocardial pe suffer from imused by multiplficity of detectin an active area of fusion is robust r DRA-free perfu tion leads to nal intensity e underlying g in the same emonstrated PEs in Panel on, zoomed- ng in (a), the DRA in Panel es (N=3) and 3T scanner cardiac-torso (>10 minutes hot Cartesian Hz/pixel; flip g rate 2 self- ian SENSE for tive gradient- cessing [6,7]. resolution for sotropic with within 10%. MP MR has bee demonstrated t tive strategy (bt scans, althoug esian schemes (e truction will be 8, 10(18). [3] DiBel g, IEEE, 1988. [6] S 2010; 64:767-76. o results for res lthy human volu ase of the co ws in (a) and (c) on-reconstruction cardial Dark-irey Merz 2 , Daniel eles, Los Angeles, ted States erfusion (MP) M age artifacts the factors and m ng subendocard f ongoing resear to Gibbs ringin usion imaging. en to improve th that projection i esides increasin gh we expect th e.g., [8,9]), rate needed. la EV, et al., MRM Song HK, et al., Mst first-pass myo unteer. Each pa ntrast uptake point to dark-ri n (radially sample Figure 1. Num intensity values projection ima Cartesian imag as highlighted 108 projection reconstruction present). (c) a zoomed-in to b Rim Artifact S. Berman 2 , and California, United MR imaging is on at reduce diagn mimic subendoca ial MP deficits. ch ([2] and refeg, a major caushe spatial resolu maging is inherg the resolution he same propert 2 parallel imagiM 2005;54:1295-59 RM 2000;44:825-3 ocardial perfusion air of Cartesian/ (late-LV or ea m artifacts (DRA ed) images in (b merical simulatio s) demonstrating aging to Gibb ging with 108 PE ); (b) projection ns and filtered (mild streaking 1D cut along th blood-pool/myoca Debiao Li 1 d States, 2 Heart ne of the most ostic accuracy, ardial perfusion Recently, there rences therein). e of DRAs; and tion (especially ently robust to n) is to employ ties to hold for ng acceleration 9. [4] Ferreira P, 32. [7] Peters DC, n scans: (a,b) /radial images arly-myocardial As). However, ) and (d). on (with realistic g robustness of s ringing. (a) Es (DRA is seen n imaging with backprojection g artifacts are he PE direction, ardium border. 1144 Proc. Intl. Soc. Mag. Reson. Med. 20 (2012)
Transcript of INTRODUCTION THEORY
1Bi
INTRchallespecidefichaveIn thwe th
THEDRAstransdata formin Fig(a) vein to strea(a)).
METhealt(Magcoil agap) (prodanglecalibradiadelayAlthothe rPE re
RESrecon(a,b) CartesameLV/eaarrowintenseen showintenwherare freduc
DISCalongGibbprojestresis notREFEet al.,et al.
ProjBehzad Sharif1, R
omedical Imaging
RODUCTIONenging dynamicifically the so-ca
cits [1-3], and are been many atteis work, we demherefore propos
EORY In Cartess due to an inhsitions [3,4]. Hotransform is the as FT (instead s
g. 1 using a numersus 108 projecthe blood-pool/
aking artifacts in
THODS To invthy human volgnetom Verio, Siarray. Two first-using a single-s
duct) sequence e = 12; TR/TE = rating parallel im
al) with 36-40 rey correction anough the readouradial scheme (≈esol. ≈2.6 mm) a
SULTS Fnstruction resul
and human (cesian/radial imae phase of thearly-myocardial ws in panels (ansities that were
in the figure,w DRAs (arrownsities) in the reas the projectfree of dark rimced contrast-to-
CUSSION Reg the PE directios ringing, a maj
ection imaging (s imaging. Howet sufficient and cERENCES [1] W, JCMR 2009;11(17MRM 2006;55:11
jection ImaginRohan Dharmakumg Research Institut
N Despite signific imaging applicalled subendocae especially limitempts at minimimonstrate that pse radial k-space
sian MP MR, Giherent property
owever, in projee Radon transforshows streaking
merical phantomctions in Panel (b/myocardium bon (b) do not resu
vestigate the valunteers (N=4; iemens AG Healtpass MP scans hot radial (custo(common param2.4/1.4 ms; TI
maging (TGRAPPeadouts. The cu
nd a 4-fold inteut resolution for≈1.8 mm vs. ≈2.2nd radial scans (
igure 2 shots for representc,d) scans. Eacages correspone contrast upta
enhancemen) and (c) point e considered DR, Cartesian imaws pointing t
subendocardiation reconstruct
ms (although wit-noise ratio).
cently, a major aon) and thereby or contributing radial trajectoriever, to match tconstrained (e.gilke NM, et al., JM
7). [5] Kak and Slan50-6. [8] Plein S, e
ng of Myocardmar1, Chrisandra Se, Cedars-Sinai M
Institute, Cedars
cant technical aations [1,2]. Curdial dark-rim ating since they czing DRAs in spe
projection imagi sampling as a p
bbs ringing alony of the Fourieection imaging (rm [5], which doartifacts if high
m simulation withb)). Fig. 1(c) showorder. It can be sult in a “signal d
idity of this obsIRB approved)
thcare, Erlangen(SR-prepared FLomized) pulse semeters: FOV rea= 100 ms). Bot
PA for Cartesian ustomized radiaerleaving schemr the Cartesian s2 mm), the over(isotropic ≈2.2 m
ows the tative dog h pair of d to the ake (late-nt). The
to hypo-RAs. As is ages (a,c) to hypo-l regions
tions (b,d) th slightly
approach for elireducing Gibbsfactor to DRAs.es). The presenhe high resoluti
g., using compresMRI 1999;10:676-68
ney, Principles of Cet al., MRM 2007;5
FhecoenD
dial PerfusionShufelt2, Troy LaB
Medical Center, ands-Sinai Medical C
advances over trrent clinical Mrtifact (DRA) [2-can reduce the secific protocols, ing of first-pass
preferred acquisi
ng the phase-ener transform (FT(radial k-space
oes not exhibit thly undersampledh realistic intensws a 1D cut alonseen that, unlikedip” (which caus
servation in-vivo were imaged
n, Germany) witLASH) were perfequence followead = 270-300 mh scans were acand self-calibratl sequence inco
me combined wscan was higher rall resolution o
mm in-plane) we
minating the DR ringing [8,9]. In We conclude ted results wereons achieved in ssed sensing) pr85. [2] Gerber BL, Computerized Tom58:777-85. [9] Ota
igure 2. Repreealthy canine morresponds to nhancement pha
DRAs are not see
n: Minimizing ounty2, Louise Thd University of Ca
Center, Los Angeles
he past decadeP MR methods 4]. DRAs are cau
sensitivity/specifyet it remains amyocardial perfition scheme for
code (PE) directT) at sharp signacquisition), thehe Gibbs ringingd). This fact is desity values (108 ng the PE directie the Gibbs ringises noticeable D
o, healthy canineon a clinical
h a 32 channel cformed at rest (ed by a single-shmm; BW ≈ 800 ccelerated usingting non-Cartesi
orporated adaptwith KWIC proc
than the base rof Cartesian (anisere matched to w
RAs in first-pass n this work, we that an alternate limited to restadvanced Carte
rojection reconstet al., JCMR 2008
mographic Imagingzo R, et al., MRM
esentative in-vivomodel; (c,d) hea
the same phaase). The arrow
en in the projectio
the Subendochomson2, Noel Baialifornia Los Anges, California, Unit
e, myocardial pesuffer from imaused by multipleficity of detectin
an active area offusion is robust r DRA-free perfu
tion leads to nal intensity e underlying g in the same emonstrated PEs in Panel on, zoomed-ng in (a), the
DRA in Panel
es (N=3) and 3T scanner
cardiac-torso (>10 minutes hot Cartesian Hz/pixel; flip g rate 2 self-ian SENSE for tive gradient-cessing [6,7]. resolution for sotropic with
within 10%.
MP MR has beedemonstrated ttive strategy (bet scans, althoug
esian schemes (etruction will be
8, 10(18). [3] DiBelg, IEEE, 1988. [6] S2010; 64:767-76.
o results for reslthy human volu
ase of the cows in (a) and (c) on-reconstruction
cardial Dark-Rirey Merz2, Danieleles, Los Angeles, Cted States
erfusion (MP) Mage artifacts thae factors and mng subendocardf ongoing resear
to Gibbs ringinusion imaging.
en to improve ththat projection iesides increasingh we expect the.g., [8,9]), rate needed. la EV, et al., MRM
Song HK, et al., MR
st first-pass myounteer. Each pantrast uptake point to dark-ri
n (radially sample
Figure 1. Numintensity valuesprojection imaCartesian imagas highlighted108 projectionreconstruction present). (c) a zoomed-in to b
Rim Artifact S. Berman2, and DCalifornia, United
MR imaging is onat reduce diagn
mimic subendocaial MP deficits. Rch ([2] and referg, a major cause
he spatial resolumaging is inhereg the resolution
he same propert2 parallel imagin
M 2005;54:1295-59RM 2000;44:825-3
ocardial perfusionair of Cartesian/(late-LV or eam artifacts (DRAed) images in (b
merical simulatios) demonstratingaging to Gibbging with 108 PE); (b) projection
ns and filtered (mild streaking1D cut along th
blood-pool/myoca
Debiao Li1 d States, 2Heart
ne of the most ostic accuracy,
ardial perfusion Recently, there rences therein). e of DRAs; and
tion (especially ently robust to n) is to employ ties to hold for ng acceleration
9. [4] Ferreira P, 32. [7] Peters DC,
n scans: (a,b) /radial images
arly-myocardial As). However, ) and (d).
on (with realistic g robustness of s ringing. (a)
Es (DRA is seen n imaging with
backprojection g artifacts are he PE direction, ardium border.
1144Proc. Intl. Soc. Mag. Reson. Med. 20 (2012)
