Details

Autor(en) / Beteiligte

• Hamilton, Gavin
• Allsop, Joanna M
• Patel, Nayna
• ton, Daniel M
• Thomas, Howard C
• O'Sullivan, Catherine PA
• Hajnal, Joseph V
• Taylor-Robinson, Simon D

Titel

Variations due to analysis technique in intracellular pH measurements in simulated and in vivo super(31)P MR spectra of the human brain

Ist Teil von

• Journal of magnetic resonance imaging, 2006-04, Vol.23 (4), p.459-464

Erscheinungsjahr

2006

Quelle

Wiley Online Library

Beschreibungen/Notizen

• To investigate variation in pH generated by different analysis techniques and to find the most robust method, super(31)P MR brain spectra were acquired in vivo. Three different methods were used to measure the chemical shift of inorganic phosphate (Pi) relative to phosphocreatine (PCr). Eight healthy volunteers were scanned four times, and manual measurement of the chemical shift in a frequency domain spectrum using the manufacturers software was compared with values produced by a frequency-domain analysis method (NMR1) and a prior- knowledge-based time-domain technique (MRUI). To explain the in vivo data, simulations of brain spectra, modified in ways typical of real variations in vivo, were produced and the pH was measured using manual measurement and MRUI. Different measurement techniques produced systematically different pH values, with manual measurement producing the lowest variability (manual measurement: pH = 6.999, CoV = 0.297; NMR1: pH = 7.042, CoV = 0.501; MRUI: pH = 7.036, CoV = 0.606). While MRUI more accurately measured the pH of unaltered simulations, it was systematically affected by altering the simulated spectra. Manual measurement was unaffected. Manual measurement produces the most consistent pH value, and there is no benefit in using more complex automated spectral fitting methods to measure the pH. J. Magn. Reson. Imaging 2006.