Improved precision in calculated T1 MR images using multiple spin-echo acquisition

Stephen J Riederer, S. A. Bobman, J. N. Lee, F. Farzaneh, H. Z. Wang

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Calculated T1 images require that magnetic resonance signals be detected at several inversion of repetition times (TR). Multiple spin-echo (SE) acquisitions provide several measurements of the magnetization at each TR, the signal size diminishing according to T2 decay. In this work we review one method (Case 1) for estimating T1 from single echoes and present four new methods (Cases 2-5) in which multiple acquired echoes are used. For Case 2 a fit is performed using the first echo at each TR, repeated using second echoes, etc., and the final T1 estimate is the simple average of the individual fits at each time (TE). For Case 3 the optimum weighted average is performed. For Cases 4 and 5 synthetic SE images are generated at each TR prior to the T1 fit, Case 4 using a synthetic TE of zero, and Case 5 using a TE providing maximum signal-to-noise ratio in the synthetic image. The relative precision in T1 provided by each method is calculated rigorously. It is proven that Cases 3 and 5 are optimum and equivalent and can theoretically reduce the noise in T1 images by as much as 40% over Case 1 with no increase in scanning time. Approximations are proposed that enable the optimum methods to be implemented in a practical fashion. Experimental images are presented that verify the relative predicted behavior.

Original languageEnglish (US)
Pages (from-to)103-110
Number of pages8
JournalJournal of Computer Assisted Tomography
Volume10
Issue number1
StatePublished - 1986
Externally publishedYes

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Signal-To-Noise Ratio
Noise
Magnetic Resonance Spectroscopy

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Improved precision in calculated T1 MR images using multiple spin-echo acquisition. / Riederer, Stephen J; Bobman, S. A.; Lee, J. N.; Farzaneh, F.; Wang, H. Z.

In: Journal of Computer Assisted Tomography, Vol. 10, No. 1, 1986, p. 103-110.

Research output: Contribution to journalArticle

Riederer, Stephen J ; Bobman, S. A. ; Lee, J. N. ; Farzaneh, F. ; Wang, H. Z. / Improved precision in calculated T1 MR images using multiple spin-echo acquisition. In: Journal of Computer Assisted Tomography. 1986 ; Vol. 10, No. 1. pp. 103-110.
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