Correcting positron emission tomography data for cerebral atrophy
Journal of Cerebral Blood Flow & Metabolism
To the Editor: We agree with Herscovitch et al. (1986) that the problem of correcting positron emission tomography (PET) data for cerebral atrophy is an important one. To our knowledge, their approach represents the best treatment of the subject in the literature to date. However, by neglecting axial resolution effects (treating the axial dimension as equivalent to the transverse plane), they introduce a source of error of unknown size into their results. Moreover, their technique is not appropriate for metabolic images derived from nonlinear models (i.e., CMR02), and their correction may not be valid for individual regions of interest.
Strother S.C. & Rottenberg D.A.