Calculation of apparent diffusion coefficients (ADCs) in brain using two-point and six-point methods

J Comput Assist Tomogr. Sep-Oct 1998;22(5):792-4. doi: 10.1097/00004728-199809000-00023.

Abstract

We evaluated the relative accuracy of calculating apparent diffusion coefficients (ADCs) of intracranial tissues using a two-point versus a six-point regression technique. Echo planar diffusion-weighted MRI was performed at 1.5 T in three standard locations and in pathologic regions in 10 subjects using gradient strengths corresponding to b values of 1, 100, 200, 500, 800, and 1,000 s/mm2. Estimation of ADCs was made using two methods: a nonlinear regression model using measurements from the full set of b values (six-point technique) and linear estimation using b values of 1 and 1,000 only (two-point technique). A high correlation between the two methods was noted (R2 = 0.999), and the mean percentage difference was 0.84%. These results suggest there is little error in estimating brain ADCs using a two-point technique.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Brain / pathology*
  • Brain Neoplasms / diagnosis
  • Cerebral Hemorrhage / diagnosis
  • Cerebral Infarction / diagnosis
  • Diffusion
  • Female
  • Hematoma / diagnosis
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Magnetic Resonance Imaging / statistics & numerical data
  • Male
  • Middle Aged
  • Reproducibility of Results