Detection of Recurrent Brain Tumor: Comparison of MR Registered Camera-Based and Dedicated PET Images

The purpose of this study is to compare the quality of images and the results of camera-based and dedicated position emission tomography (PET) in the same patients with suspected recurrent or persistent brain tumor after therapy. Both PET studies were interpreted using registration with contrast-enhanced magnetic resonance imaging (MRI) studies. Twenty-three patients with 24 contrast-enhancing lesions by MRI were included. Camera-based PET images were more difficult to register and resulted in less accurate automated determination of the edge because of image noise. Dedicated PET images demonstrated better gray matter to white matter discrimination in every patient. Camera-based PET identified tumor in 17 of 19 lesions that were abnormal for tumor by dedicated PET. Camera-based PET identified absence of tumor in 4 of 5 lesions considered negative for tumor by dedicated PET. Thus, despite the limitations related to camera-based PET, the overall concordance of interpretation using MRI registered images is good.