Lactate doublet quantification and lipid signal suppression using a new biexponential decay filter: Application to simulated and 1 H MRS brain tumor time‐domain data

A new postprocessing filter based on the continuous wavelet transform (CWT) method modeled as a biexponential decay function to isolate the lactate doublet from overlapping lipid resonance(s) and estimate its magnetic resonance spectroscopy (MRS) parameters (signal amplitude, resonance frequencies, and apparent relaxation time ( T   * 2 )) is proposed. The new filter employs the same iterative process used in the previously single exponential decay filter. A comparison of the results obtained from application of both filters to simulated data and real 1 H MRS data collected from human blood plasma and brain tumors demonstrates that the new filter provides a better estimate of MRS parameters of lactate, with less computation time. Furthermore, the results show that the new filter is less sensitive to noise and provides a direct estimate of J ‐coupling value of the lactate doublet. Magn Reson Med 50:623–626, 2003. © 2003 Wiley‐Liss, Inc.