Partial volume mapping using magnetic resonance fingerprinting. (1st March 2019)

• Record Type: Journal Article
• Authors: Deshmane, Anagha; McGivney, Debra F.; Ma, Dan; Jiang, Yun; Badve, Chaitra; Gulani, Vikas; Seiberlich, Nicole; Griswold, Mark A.
• Is Part Of: NMR in biomedicine. Volume 32:Number 5(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-03-01
• Subjects: quantitative MRI -- tissue fractions -- tissue mapping; Nuclear magnetic resonance -- Periodicals; Magnetic Resonance Spectroscopy -- Periodicals; 574
• DOI: 10.1002/nbm.4082
• Languages: English
• ISSNs: 0952-3480

Abstract

Abstract : Magnetic resonance fingerprinting (MRF) is a quantitative imaging technique that maps multiple tissue properties through pseudorandom signal excitation and dictionary‐based reconstruction. The aim of this study is to estimate and validate partial volumes from MRF signal evolutions (PV‐MRF), and to characterize possible sources of error. Partial volume model inversion (pseudoinverse) and dictionary‐matching approaches to calculate brain tissue fractions (cerebrospinal fluid, gray matter, white matter) were compared in a numerical phantom and seven healthy subjects scanned at 3 T. Results were validated by comparison with ground truth in simulations and ROI analysis in vivo. Simulations investigated tissue fraction errors arising from noise, undersampling artifacts, and model errors. An expanded partial volume model was investigated in a brain tumor patient. PV‐MRF with dictionary matching is robust to noise, and estimated tissue fractions are sensitive to model errors. A 6% error in pure tissue T1 resulted in average absolute tissue fraction error of 4% or less. A partial volume model within these accuracy limits could be semi‐automatically constructed in vivo using k ‐means clustering of MRF‐mapped relaxation times. Dictionary‐based PV‐MRF robustly identifies pure white matter, gray matter and cerebrospinal fluid, and partial volumes in subcortical structures. PV‐MRF could also estimate partial volumes of solid tumor and peritumoral edema. We conclude that PV‐MRF can attribute subtle changes in relaxation times to altered tissue composition, allowing for quantification of specific tissues which occupy a fraction of a voxel. Abstract : Two methods for partial volume estimation from magnetic resonance fingerprinting (MRF) voxel signal evolutions are compared in realistic simulations and in vivo. A dictionary‐based calculation is shown to be robust to high rates of undersampling in MRF experiments. Partial volume component tissues were selected based on k ‐means clustering of mapped T1 and T2 values. Using this approach, estimated tissue fractions were reproducible in seven healthy subjects. The partial volume model could be expanded to estimate fractions of diseased tissues.