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Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters: A framework for enhanced precision of DESPOT T1 and T2 estimation

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Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters : A framework for enhanced precision of DESPOT T1 and T2 estimation. / Teixeira, Rui Pedro A G; Malik, Shaihan J.; Hajnal, Joseph V.

In: Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine, 16.03.2017.

Research output: Contribution to journalArticle

Harvard

Teixeira, RPAG, Malik, SJ & Hajnal, JV 2017, 'Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters: A framework for enhanced precision of DESPOT T1 and T2 estimation', Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine. https://doi.org/10.1002/mrm.26670

APA

Teixeira, R. P. A. G., Malik, S. J., & Hajnal, J. V. (2017). Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters: A framework for enhanced precision of DESPOT T1 and T2 estimation. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine. https://doi.org/10.1002/mrm.26670

Vancouver

Teixeira RPAG, Malik SJ, Hajnal JV. Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters: A framework for enhanced precision of DESPOT T1 and T2 estimation. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine. 2017 Mar 16. https://doi.org/10.1002/mrm.26670

Author

Teixeira, Rui Pedro A G ; Malik, Shaihan J. ; Hajnal, Joseph V. / Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters : A framework for enhanced precision of DESPOT T1 and T2 estimation. In: Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine. 2017.

Bibtex Download

@article{94e05ad35f7645b897f674c581891866,
title = "Joint system relaxometry (JSR) and Cr{\'a}mer-Rao lower bound optimization of sequence parameters: A framework for enhanced precision of DESPOT T1 and T2 estimation",
abstract = "Purpose: This study aims to increase the precision of single-compartment DESPOT relaxometry by two means: (i) a joint system relaxometry (JSR) approach that estimates parameters in a single step using all available data; and (ii) optimizing acquisition parameters by deploying a robust design tool based on the Cr{\'a}mer-Rao lower bound (CRLB). Methods: Following the development of the analysis and design capabilities, phantom and four in vivo subject experiments were performed to compare directly the precision achieved with DESPOT and JSR estimation using published protocols and protocols designed using a proposed CRLB framework. Results: Experimental data demonstrate JSR's ability to decrease relaxometry estimation variance. Phantom results show 72 to 77{\%} improvement using the same data as conventional DESPOT. This is further improved to 81 to 87{\%} using optimal parameters. Both experiments show systematic bias depending on the acquisition parameters used, which are shown to be highly reproducible and to vary with different magnetization transfer conditions. Conclusions: Compared with DESPOT, JSR produces reproducible relaxation maps with improved precision. Further improvement was achieved using CRLB as a protocol design tool. With this combined approach, it is possible to achieve submillimeter maps of ρ,T1,T2, and B0 in an 11-min examination, making the approach appealing for potential clinical use.",
keywords = "CRLB, DESPOT, Relaxometry",
author = "Teixeira, {Rui Pedro A G} and Malik, {Shaihan J.} and Hajnal, {Joseph V.}",
note = "{\circledC} 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.",
year = "2017",
month = "3",
day = "16",
doi = "10.1002/mrm.26670",
language = "English",
journal = "Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine",
issn = "1522-2594",

}

RIS (suitable for import to EndNote) Download

TY - JOUR

T1 - Joint system relaxometry (JSR) and Crámer-Rao lower bound optimization of sequence parameters

T2 - A framework for enhanced precision of DESPOT T1 and T2 estimation

AU - Teixeira, Rui Pedro A G

AU - Malik, Shaihan J.

AU - Hajnal, Joseph V.

N1 - © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

PY - 2017/3/16

Y1 - 2017/3/16

N2 - Purpose: This study aims to increase the precision of single-compartment DESPOT relaxometry by two means: (i) a joint system relaxometry (JSR) approach that estimates parameters in a single step using all available data; and (ii) optimizing acquisition parameters by deploying a robust design tool based on the Crámer-Rao lower bound (CRLB). Methods: Following the development of the analysis and design capabilities, phantom and four in vivo subject experiments were performed to compare directly the precision achieved with DESPOT and JSR estimation using published protocols and protocols designed using a proposed CRLB framework. Results: Experimental data demonstrate JSR's ability to decrease relaxometry estimation variance. Phantom results show 72 to 77% improvement using the same data as conventional DESPOT. This is further improved to 81 to 87% using optimal parameters. Both experiments show systematic bias depending on the acquisition parameters used, which are shown to be highly reproducible and to vary with different magnetization transfer conditions. Conclusions: Compared with DESPOT, JSR produces reproducible relaxation maps with improved precision. Further improvement was achieved using CRLB as a protocol design tool. With this combined approach, it is possible to achieve submillimeter maps of ρ,T1,T2, and B0 in an 11-min examination, making the approach appealing for potential clinical use.

AB - Purpose: This study aims to increase the precision of single-compartment DESPOT relaxometry by two means: (i) a joint system relaxometry (JSR) approach that estimates parameters in a single step using all available data; and (ii) optimizing acquisition parameters by deploying a robust design tool based on the Crámer-Rao lower bound (CRLB). Methods: Following the development of the analysis and design capabilities, phantom and four in vivo subject experiments were performed to compare directly the precision achieved with DESPOT and JSR estimation using published protocols and protocols designed using a proposed CRLB framework. Results: Experimental data demonstrate JSR's ability to decrease relaxometry estimation variance. Phantom results show 72 to 77% improvement using the same data as conventional DESPOT. This is further improved to 81 to 87% using optimal parameters. Both experiments show systematic bias depending on the acquisition parameters used, which are shown to be highly reproducible and to vary with different magnetization transfer conditions. Conclusions: Compared with DESPOT, JSR produces reproducible relaxation maps with improved precision. Further improvement was achieved using CRLB as a protocol design tool. With this combined approach, it is possible to achieve submillimeter maps of ρ,T1,T2, and B0 in an 11-min examination, making the approach appealing for potential clinical use.

KW - CRLB

KW - DESPOT

KW - Relaxometry

UR - http://www.scopus.com/inward/record.url?scp=85016598161&partnerID=8YFLogxK

U2 - 10.1002/mrm.26670

DO - 10.1002/mrm.26670

M3 - Article

C2 - 28303617

JO - Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine

JF - Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine

SN - 1522-2594

ER -

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