Use of voigt lineshape for quantification of in vivo1H spectra

✍ Scribed by Ian Marshall; John Higinbotham; Stephen Bruce; Andreas Freise

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 671 KB
• Volume: 37
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1910370504

✦ Synopsis

Abstract

Quantification of NMR visible metabolites by spectral modeling usually assumes a Lorentzian or Gaussian lineshape, despite the fact that experimental lineshapes are neither. To minimize systematic fitting errors, a mixed Lorentzian‐Gaussian (Voigt) lineshape model was developed. When tested with synthetic FIDs, the Voigt lineshape model gave more accurate results (maximum error 2%) than either Lorentzian (maximum error 20%) or Gaussian models (maximum error 12%). The three lineshape models gave substantially different peak areas in an in vitro experiment, with the Voigt model having a much lower X^2^ (2.1 compared with 5.2 for the Lorentzian model and 6.2 for the Gaussian model). In a group of 10 healthy volunteers, fitting of ^1^H spectra from cerebral white matter gave significantly different peak areas between the methods. Even when area ratios were taken, the Lorentzian model gave higher values (+5% for NAA/choline and +2% for NAA/creatine) than the Voigt lineshape model, whereas the Gaussian model gave lower values (−2% and −1%, respectively).