Hybrid imaging: applications of PET-MRI in neurodegenerative disorders

Clinical techniques are limited in its evaluation of neurodegenerative disorders due to its low clinical accuracy in the early diagnosis of these disorders. Nuclear imaging has the advantage via SPECT, SPECT-CT or PET-CT imaging to detect functional changes in the brain before they are fully manifested clinically. However, these modalities have limited anatomical details that can easily miss contributing or underlying pathology that may underwrite to patient presentation. The simultaneous acquisition of Fluorodeoxyglucose Positron Emission Tomography together with Magnetic Resonance Imaging (FDG PET-MRI) localizes pathological areas of interest adding significant anatomical and structural detail, and improves diagnostic accuracy. In addition, PET-MRI may show an underlying tumor, epileptic focus, inflammatory processes, or vascular causes of patient symptoms such as multi infarct dementia. Overall FDG PET-MRI of the brain demonstrates additive value in evaluating patients with suspected dementia by increasing diagnostic confidence, limiting radiation compared to CT, and providing more comprehensive information not normally obtained on PET-CT. PET-CT can be used to distinguish the myriad of comorbidities contributing to patient symptoms and incidental findings in which further follow up is warranted. The focus of this talk will be to discuss principles, techniques and clinical applications of simultaneous FDG PET-MRI in evaluating neurodegenerative conditions. Furthermore, key imaging findings resulting from neurodegenerative disorders and inflammatory conditions will be presented