Akçakaya, Mehmet

Basha, Tamer A

Nezafat, Reza

Roujol, Sébastien

Weingärtner, Sebastian

Journal of Cardiovascular Magnetic Resonance

Mehmet Akçakaya

Sebastian Weingärtner

Tamer A Basha

Sébastien Roujol

Reza Nezafat

Springer - Publisher Connector

WALKING POSTER PRESENTATION Open Access
Joint myocardial T1 and T2 mapping
Mehmet Akçakaya1*, Sebastian Weingärtner1,2, Tamer A Basha1, Sébastien Roujol1, Reza Nezafat1
From 18th Annual SCMR Scientific Sessions
Nice, France. 4-7 February 2015
Background
Recent studies suggest that quantitative myocardial T1
mapping allows assessment of focal and diffuse fibrosis
in the myocardium [1]. Quantitative T2 mapping has
also been proposed to overcome challenges associated
with T2 weighted imaging [2]. These maps are tradition-
ally acquired with different sequences, necessitating
image registration to evaluate them jointly. A sequence
that can jointly estimate T1 and T2 maps has been pro-
posed [3], but it requires multiple relaxation cycles,
which necessitates a lengthy free-breathing acquisition.
In [4], an alternative joint estimation sequence was pro-
posed based on the inversion-recovery SSFP curve. In
this study, we sought to develop a saturation-recovery
1Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School,
Boston, MA, USA
Full list of author information is available at the end of the article
Figure 1 a) The sequence diagram for the proposed technique. A saturation pulse is applied in every R-R interval to eliminate the
magnetization history. The longitudinal magnetization then recovers for Tsat. Subsequently a T2-prep with echo length TEprep is applied to
generate the additional T2 weighting, after which a single shot SSFP image is acquired. b) The mapping sequence acquires the first image with
no magnetization preparation (corresponding to Tsat = ∞ and TEprep = 0), followed by 12 images (3 are shown) acquired with different Tsat and
TEprep values. The major characteristics of the longitudinal magnetization signal curve are depicted under the pulse sequence diagram.
Akçakaya et al. Journal of Cardiovascular Magnetic
Resonance 2015, 17(Suppl 1):Q1
http://www.jcmr-online.com/content/17/S1/Q1
© 2015 Akçakaya et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
based heart-rate independent sequence that can be
acquired in a breath-hold and that allows for simulta-
neous estimation of quantitative T1 and T2 maps.
Methods
The sequence diagram is depicted in Figure 1. At every
heartbeat, a saturation pulse is applied to eliminate the
magnetization history. The longitudinal magnetization
then recovers for Tsat based on the T1 value. Subse-
quently a T2-prep pulse [5] with echo length TEprep is
applied to generate the additional T2 weighting, after
which a single shot SSFP image is acquired. The process
is repeated for 13 heartbeats with various (Tsat
k, TEprep
k)
corresponding to heartbeat k, to sample different T1-T2
weighted images. The first heartbeat is acquired with no
magnetization preparation.
The T1 and T2 maps were estimated jointly by voxel-
wise least squares fitting to a 4-parameter signal model,
A (1- exp(-Tsat
k/T1)) exp(-TEprep
k/T2) + B. Phantom
imaging of 14 vials with different T1/T2 values were per-
formed and compared to inversion-recovery and CPMG
spin-echo references, respectively. Breath-held in-vivo
imaging was performed on 5 healthy adult subjects, and
the maps were compared to SASHA T1 maps [6] and to
T2 maps [7].
Results
Phantom imaging resulted in T1 and T2 values not sig-
nificantly different than the references (P = 0.481 and
0.479 respectively). Example in-vivo T1 and T2 maps are
depicted in Figure 2, comparing various techniques. The
T1 and T2 values were in good agreement (1211 ± 82
ms vs. 1210 ± 92 ms for T1; 49.0 ± 5.8 ms and 47.3 ±
6.5 ms for T2).
Conclusions
The proposed sequence allows for the simultaneous esti-
mation of accurate and jointly registered quantitative T1
and T2 maps with similar accuracy and precision to
saturation-based T1 mapping and to T2 mapping of
same duration.
Funding
NIH:K99HL111410-01; R01EB008743-01A2.
Figure 2 T1 and T maps from a healthy subject, acquired using the proposed technique, as well as SASHA T1 mapping, and conventional T2
mapping using 4 T2prep echo times. Both the T1 and T2 maps generated jointly with the proposed method are similar to the individual maps
with similar magnetization preparations. The myocardial T1 and T2 values in the septum were 1211 ± 82 ms (SASHA T1), 1210 ± 92 ms (Joint T1-
T2), 49.0 ± 5.8 ms (conventional T2) and 47.3 ± 6.5 ms (Joint T1-T2) for each technique. The methods generated with the proposed method were
acquired in the same time as each individual map, and are jointly registered by design.
Akçakaya et al. Journal of Cardiovascular Magnetic
Resonance 2015, 17(Suppl 1):Q1
http://www.jcmr-online.com/content/17/S1/Q1
Page 2 of 3
Authors’ details
1Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School,
Boston, MA, USA. 2Computer Assisted Clinical Medicine, University Medical
Center Mannheim, Heidelberg University, Mannheim, Germany.
Published: 3 February 2015
References
1. Mewton: JACC 2011.
2. Giri: JCMR 2009.
3. Sinclair: JMRI 2009.
4. Santini: MRM 2014.
5. Brittain: MRM 1995.
6. Chow: MRM 2013.
7. Akçakaya: MRM 2014.
doi:10.1186/1532-429X-17-S1-Q1
Cite this article as: Akçakaya et al.: Joint myocardial T1 and T2 mapping.
Journal of Cardiovascular Magnetic Resonance 2015 17(Suppl 1):Q1.
Submit your next manuscript to BioMed Central
and take full advantage of: 
• Convenient online submission
• Thorough peer review
• No space constraints or color figure charges
• Immediate publication on acceptance
• Inclusion in PubMed, CAS, Scopus and Google Scholar
• Research which is freely available for redistribution
Submit your manuscript at 
www.biomedcentral.com/submit
Akçakaya et al. Journal of Cardiovascular Magnetic
Resonance 2015, 17(Suppl 1):Q1
http://www.jcmr-online.com/content/17/S1/Q1
Page 3 of 3


Joint myocardial T1 and T2 mapping

Harvard University - DASH 

Joint myocardial T1 and T2 mappingThe Harvard community has made thisarticle openly available.  Please share  howthis access benefits you. Your story mattersCitation Akçakaya, Mehmet, Sebastian Weingärtner, Tamer A Basha,Sébastien Roujol, and Reza Nezafat. 2015. “Joint myocardialT1 and T2 mapping.” Journal of Cardiovascular MagneticResonance 17 (1): Q1. doi:10.1186/1532-429X-17-S1-Q1. http://dx.doi.org/10.1186/1532-429X-17-S1-Q1.Published Version doi:10.1186/1532-429X-17-S1-Q1Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:14065497Terms of Use This article was downloaded from Harvard University’s DASHrepository, and is made available under the terms and conditionsapplicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAAWALKING POSTER PRESENTATION Open AccessJoint myocardial T1 and T2 mappingMehmet Akçakaya1*, Sebastian Weingärtner1,2, Tamer A Basha1, Sébastien Roujol1, Reza Nezafat1From 18th Annual SCMR Scientific SessionsNice, France. 4-7 February 2015BackgroundRecent studies suggest that quantitative myocardial T1mapping allows assessment of focal and diffuse fibrosisin the myocardium [1]. Quantitative T2 mapping hasalso been proposed to overcome challenges associatedwith T2 weighted imaging [2]. These maps are tradition-ally acquired with different sequences, necessitatingimage registration to evaluate them jointly. A sequencethat can jointly estimate T1 and T2 maps has been pro-posed [3], but it requires multiple relaxation cycles,which necessitates a lengthy free-breathing acquisition.In [4], an alternative joint estimation sequence was pro-posed based on the inversion-recovery SSFP curve. Inthis study, we sought to develop a saturation-recovery1Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School,Boston, MA, USAFull list of author information is available at the end of the articleFigure 1 a) The sequence diagram for the proposed technique. A saturation pulse is applied in every R-R interval to eliminate themagnetization history. The longitudinal magnetization then recovers for Tsat. Subsequently a T2-prep with echo length TEprep is applied togenerate the additional T2 weighting, after which a single shot SSFP image is acquired. b) The mapping sequence acquires the first image withno magnetization preparation (corresponding to Tsat = ∞ and TEprep = 0), followed by 12 images (3 are shown) acquired with different Tsat andTEprep values. The major characteristics of the longitudinal magnetization signal curve are depicted under the pulse sequence diagram.Akçakaya et al. Journal of Cardiovascular MagneticResonance 2015, 17(Suppl 1):Q1http://www.jcmr-online.com/content/17/S1/Q1© 2015 Akçakaya et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the CreativeCommons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, andreproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.based heart-rate independent sequence that can beacquired in a breath-hold and that allows for simulta-neous estimation of quantitative T1 and T2 maps.MethodsThe sequence diagram is depicted in Figure 1. At everyheartbeat, a saturation pulse is applied to eliminate themagnetization history. The longitudinal magnetizationthen recovers for Tsat based on the T1 value. Subse-quently a T2-prep pulse [5] with echo length TEprep isapplied to generate the additional T2 weighting, afterwhich a single shot SSFP image is acquired. The processis repeated for 13 heartbeats with various (Tsatk, TEprepk)corresponding to heartbeat k, to sample different T1-T2weighted images. The first heartbeat is acquired with nomagnetization preparation.The T1 and T2 maps were estimated jointly by voxel-wise least squares fitting to a 4-parameter signal model,A (1- exp(-Tsatk/T1)) exp(-TEprepk/T2) + B. Phantomimaging of 14 vials with different T1/T2 values were per-formed and compared to inversion-recovery and CPMGspin-echo references, respectively. Breath-held in-vivoimaging was performed on 5 healthy adult subjects, andthe maps were compared to SASHA T1 maps [6] and toT2 maps [7].ResultsPhantom imaging resulted in T1 and T2 values not sig-nificantly different than the references (P = 0.481 and0.479 respectively). Example in-vivo T1 and T2 maps aredepicted in Figure 2, comparing various techniques. TheT1 and T2 values were in good agreement (1211 ± 82ms vs. 1210 ± 92 ms for T1; 49.0 ± 5.8 ms and 47.3 ±6.5 ms for T2).ConclusionsThe proposed sequence allows for the simultaneous esti-mation of accurate and jointly registered quantitative T1and T2 maps with similar accuracy and precision tosaturation-based T1 mapping and to T2 mapping ofsame duration.FundingNIH:K99HL111410-01; R01EB008743-01A2.Figure 2 T1 and T maps from a healthy subject, acquired using the proposed technique, as well as SASHA T1 mapping, and conventional T2mapping using 4 T2prep echo times. Both the T1 and T2 maps generated jointly with the proposed method are similar to the individual mapswith similar magnetization preparations. The myocardial T1 and T2 values in the septum were 1211 ± 82 ms (SASHA T1), 1210 ± 92 ms (Joint T1-T2), 49.0 ± 5.8 ms (conventional T2) and 47.3 ± 6.5 ms (Joint T1-T2) for each technique. The methods generated with the proposed method wereacquired in the same time as each individual map, and are jointly registered by design.Akçakaya et al. Journal of Cardiovascular MagneticResonance 2015, 17(Suppl 1):Q1http://www.jcmr-online.com/content/17/S1/Q1Page 2 of 3Authors’ details1Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School,Boston, MA, USA. 2Computer Assisted Clinical Medicine, University MedicalCenter Mannheim, Heidelberg University, Mannheim, Germany.Published: 3 February 2015References1. Mewton: JACC 2011.2. Giri: JCMR 2009.3. Sinclair: JMRI 2009.4. Santini: MRM 2014.5. Brittain: MRM 1995.6. Chow: MRM 2013.7. Akçakaya: MRM 2014.doi:10.1186/1532-429X-17-S1-Q1Cite this article as: Akçakaya et al.: Joint myocardial T1 and T2 mapping.Journal of Cardiovascular Magnetic Resonance 2015 17(Suppl 1):Q1.Submit your next manuscript to BioMed Centraland take full advantage of: • Convenient online submission• Thorough peer review• No space constraints or color figure charges• Immediate publication on acceptance• Inclusion in PubMed, CAS, Scopus and Google Scholar• Research which is freely available for redistributionSubmit your manuscript at www.biomedcentral.com/submitAkçakaya et al. Journal of Cardiovascular MagneticResonance 2015, 17(Suppl 1):Q1http://www.jcmr-online.com/content/17/S1/Q1Page 3 of 3

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