Log subtracted inversion recovery

Mark Bydder; Daniel M Cornfeld; Tracy R Melzer; Paul Condron; Gil Newburn; Eryn E Kwon; Maryam Tayebi; Miriam Scadeng; Samantha J Holdsworth; Graeme M Bydder

doi:10.1016/j.mri.2025.110328

Log subtracted inversion recovery

Magn Reson Imaging. 2025 Jan 16:117:110328. doi: 10.1016/j.mri.2025.110328. Online ahead of print.

Authors

Affiliations

¹ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand. Electronic address: [email protected].
² Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand; Department of Anatomy & Medical Imaging, Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, New Zealand. Electronic address: [email protected].
³ Department of Medicine, University of Otago, Christchurch 8011, New Zealand; New Zealand Brain Research Institute, Christchurch 8011, New Zealand; Te Kura Mahi ā-Hirikapo, School of Psychology, Speech and Hearing, University of Canterbury, Christchurch 8140, New Zealand. Electronic address: [email protected].
⁴ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand; Department of Anatomy & Medical Imaging, Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, New Zealand. Electronic address: [email protected].
⁵ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand. Electronic address: [email protected].
⁶ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand; Department of Anatomy & Medical Imaging, Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, New Zealand; Auckland Bioengineering Institute, Auckland, New Zealand. Electronic address: [email protected].
⁷ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand; Department of Anatomy & Medical Imaging, Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, New Zealand. Electronic address: [email protected].
⁸ Department of Anatomy & Medical Imaging, Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, New Zealand; Auckland Bioengineering Institute, Auckland, New Zealand. Electronic address: [email protected].
⁹ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand; Department of Anatomy & Medical Imaging, Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, New Zealand. Electronic address: [email protected].
¹⁰ Mātai Medical Research Institute, Tairāwhiti, Gisborne, New Zealand; Department of Radiology, University of California San Diego, San Diego, CA, USA. Electronic address: [email protected].

PMID: 39826592
DOI: 10.1016/j.mri.2025.110328

Abstract

Magnetic resonance imaging (MRI) techniques have recently been developed for obtaining high T₁ contrast images using inversion recovery (IR) images at two inversion times (TIs) rather than a single TI. They use simple mathematical operations - multiplication, addition, subtraction, division - to create images not attainable by conventional IR. The present study describes a novel two-point IR technique formed by the subtraction of log images. Results show it has a near-linear response to T₁ between the nullpoints that peaks sharply at the nullpoints. This produces a bright isoT₁ contour at interfaces between tissues where partial volume mixing generates specific T₁s. This can provide anatomical information in areas where the signal is not well-differentiated on conventional images.

Keywords: FLAWS; Inversion recovery; MP2RAGE; T1 mapping; dSIR.