Feasibility of short imaging protocols for [18F]fluordeprenyl-D2 PET in autoimmune encephalitis and multiple system atrophy

Tagnin, Lisa ; Dorneich, Julia S.; Zeinaki, Marianthi; Vogler, Letizia; Sanzo, Laura; Gnörich, Johannes S. ; Katzdobler, Sabrina ; Masouris, Ilias ; Jäck, Alexander; Bernhardt, Alexander M. ; Rauchmann, Boris-Stephan ; Stoecklein, Sophia ; Simmet, Marcel; Joseph, Emanuel; Lindner, Simon ; Koglin, Norman; Mueller, Andre; Stephens, Andrew W.; Bischof, Gérard N.; Frontzkowski, Lukas Karl; Franzmeier, Nicolai ; Werner, Rudolf A.; Gernert, Jonathan A. ; Hopfner, Franziska ; Höglinger, Günter U. ; Perneczky, Robert ; Kurz, Carolin ; Kümpfel, Tania ; Kerschensteiner, Martin ; Thaler, Franziska S. ; Levin, Johannes und Brendel, Matthias (2026): Feasibility of short imaging protocols for [18F]fluordeprenyl-D2 PET in autoimmune encephalitis and multiple system atrophy. In: European Journal of Nuclear Medicine and Molecular Imaging [Forthcoming]

Abstract

Introduction: [18F]fluorodeprenyl-D2 ([18F]F-DED) positron emission tomography (PET) imaging detects reactive astrogliosis in patients with autoimmune encephalitis (AIE) and multiple system atrophy (MSA). Although dynamic 60-min acquisitions are established, shorter static imaging protocols are desirable for severely impaired patients. This study investigated the feasibility of short static time windows for [18F]F-DED PET imaging in AIE and MSA.

Methods: Dynamic 60-min [18F]F-DED PET scans were analyzed in 20 patients with AIE, 20 patients with MSA (MSA-P/MSA-C), and 16 controls (CTRL). Disease-related lesions were manually segmented based on visually detectable positive PET-signal in AIE and MSA predilection sites (i.e. mesial temporal lobe, posterior putamen, cerebellar deep white matter), and standardized uptake value ratios (SUVr; cerebellar cortex as a reference tissue) were calculated for consecutive 10-min intervals. Advanced kinetic parameters (DVR, VTr) were derived using Logan plot and a one-tissue compartment model (1TC2k) with image-derived input functions, both applying the cerebellar cortex as a reference tissue.

Results: Static images acquired between 10 and 60 min p.i. showed good image contrast and signal-to-noise ratio. SUVr of lesions increased over time and approached a plateau at approximately 50–60 min p.i.. The strongest agreement between SUVr and DVR was observed between 30 and 50 min p.i.. Late-phase SUVr outperformed kinetic parameters in discriminating lesions from healthy tissue in both AIE and MSA.

Conclusion: Short static [18F⁸ ]F-DED PET acquisitions are clinically robust for detecting neuroinflammation in AIE and MSA. A late static acquisition between 30–50 min p.i. provides the optimal balance between accuracy and scanning efficiency.

• Item Type: Journal article
• Faculties: Medicine > Biomedical Center; Medicine > Institute for Immunology; Medicine > Munich Cluster for Systems Neurology (SyNergy); Medicine > Institute for Stroke and Dementia Research (ISD); Medicine > Institute for Diagnostic and Interventional Neuroradiology; Medicine > Medical Center of the University of Munich > Neurological Clinic and Polyclinic with Friedrich Baur Institute; Medicine > Medical Center of the University of Munich > Clinic and Polyclinic for Nuclear Medicine; Medicine > Medical Center of the University of Munich > Clinic and Polyclinic for Psychiatry and Psychotherapy; Medicine > Medical Center of the University of Munich > Clinic and Polyclinic for Radiology
• Subjects: 600 Technology > 610 Medicine and health
• ISSN: 1619-7070
• Language: English
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 390857198