MRI guided segmentation and quantification of SPECT images of the basal ganglia: a phantom study

Due to the limited resolution of single-photon emission computed tomography (SPECT) imaging devices, tissue interfaces are not well defined in the rec onstructed image, even though resolution recovery techniques may be used du ring reconstruction. Therefore, segmentation of a particular region and qua ntification of the tracer uptake in that region is critical due to spillove r effects, when based on the SPECT image only. In this study, we present tw o methods for quantification of tracer uptake in a SPECT image, defined by a matched high resolution structural magnetic resonance image. We show prel iminary results of both techniques, when applied for quantifying regional u ptake in the different compartments of a phantom simulating the basal gangl ia. These results indicate that the quantification method, which takes into account the blurring by the SPECT imaging device, promises to be perform b etter in the presence of background activity. (C) 2001 Elsevier Science Ltd . All rights reserved.