Browsing by Author "Fleisher, Adam S."

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    Clinical use of amyloid-positron emission tomography neuroimaging: Practical and bioethical considerations
    (Elsevier, 2015-09) Witte, Michael M.; Foster, Norman L.; Fleisher, Adam S.; Williams, Monique M.; Quaid, Kimberly; Wasserman, Michael; Hunt, Gail; Roberts, J. Scott; Rabinovici, Gil D.; Levenson, James L.; Hake, Ann Marie; Hunter, Craig A.; Van Campen, Luann E.; Pontecorvo, Michael J.; Hochstetler, Helen M.; Tabas, Linda B.; Trzepacz, Paula T.; Department of Neurology, IU School of Medicine
    Until recently, estimation of β-amyloid plaque density as a key element for identifying Alzheimer's disease (AD) pathology as the cause of cognitive impairment was only possible at autopsy. Now with amyloid-positron emission tomography (amyloid-PET) neuroimaging, this AD hallmark can be detected antemortem. Practitioners and patients need to better understand potential diagnostic benefits and limitations of amyloid-PET and the complex practical, ethical, and social implications surrounding this new technology. To complement the practical considerations, Eli Lilly and Company sponsored a Bioethics Advisory Board to discuss ethical issues that might arise from clinical use of amyloid-PET neuroimaging with patients being evaluated for causes of cognitive decline. To best address the multifaceted issues associated with amyloid-PET neuroimaging, we recommend this technology be used only by experienced imaging and treating physicians in appropriately selected patients and only in the context of a comprehensive clinical evaluation with adequate explanations before and after the scan.
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    Topographic staging of tau positron emission tomography images
    (Elsevier, 2018-02-14) Schwarz, Adam J.; Shcherbinin, Sergey; Slieker, Lawrence J.; Risacher, Shannon L.; Charil, Arnaud; Irizarry, Michael C.; Fleisher, Adam S.; Southekal, Sudeepti; Joshi, Abhinay D.; Devous, Michael D., Sr.; Miller, Bradley B.; Saykin, Andrew J.; Alzheimer's Disease Neuroimaging Initiative; Radiology and Imaging Sciences, School of Medicine
    Introduction: It has been proposed that the signal distribution on tau positron emission tomography (PET) images could be used to define pathologic stages similar to those seen in neuropathology. Methods: Three topographic staging schemes for tau PET, two sampling the temporal and occipital subregions only and one sampling cortical gray matter across the major brain lobes, were evaluated on flortaucipir F 18 PET images in a test-retest scenario and from Alzheimer's Disease Neuroimaging Initiative 2. Results: All three schemes estimated stages that were significantly associated with amyloid status and when dichotomized to tau positive or negative were 90% to 94% concordant in the populations identified. However, the schemes with fewer regions and simpler decision rules yielded more robust performance in terms of fewer unclassified scans and increased test-retest reproducibility of assigned stage. Discussion: Tau PET staging schemes could be useful tools to concisely index the regional involvement of tau pathology in living subjects. Simpler schemes may be more robust.