title: Brain perfusion SPECT in limbic encephalitis associated with autoantibody against the glutamate receptor epsilon 2.
abstract: OBJECTIVE
  The aim of this study was to elucidate the single-photon emission computed tomography (SPECT) pattern at the acute stage of disease in non-herpetic limbic encephalitis (NHLE) patients associated with the N-methyl-D-aspartate-type glutamate receptor epsilon 2 (GluR ϵ2) autoantibody using Z-score imaging system (eZIS) analyses.
  
  
  METHODS
  Brain magnetic resonance imaging (MRI) and brain perfusion SPECT using technetium-99 ethyl cysteinate dimer ((99m)Tc-ECD) were performed in eight patients with NHLE (5 men and 3 women; mean age 48.8±22 years) within 20days after clinical onset.
  
  
  RESULTS
  All patients had various clinical limbic-associated symptoms and no evidence of herpes simplex infection or systemic malignancies. Two of eight patients showed abnormally hyperintense lesions on diffusion-weighted images and significant hyperperfusion in ipsilateral cerebral cortex on eZIS analysis, whereas other patients showed normal MRI findings and significant hypoperfusion in one or both sides of the limbic and paralimbic areas.
  
  
  CONCLUSIONS
  We suggest that (99m)Tc-ECD SPECT study using eZIS analyses may be helpful to detect the neuronal dysfunction, particularly in NHLE patients without abnormal MRI findings.
authors: Department of Neurology and Neuromuscular Disorders, Oita University, Faculty of Medicine, Oita, Japan. Electronic address: noriyuki@oita-u.ac.jp.
authors: Noriyuki
authors: N
authors: Kimura
authors: Department of Neurology and Neuromuscular Disorders, Oita University, Faculty of Medicine, Oita, Japan.
authors: Toshihide
authors: T
authors: Kumamoto
authors: National Epilepsy Center, Shizuoka Institute Epilepsy and Neurological Disorders, Shizuoka, Japan.
authors: Yukitoshi
authors: Y
authors: Takahashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000276:immunology*; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D003545:Cysteine / Q000031:analogs & derivatives; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020363:Limbic Encephalitis / Q000000981:diagnostic imaging* / Q000276:immunology* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D016194:Receptors, N-Methyl-D-Aspartate / Q000276:immunology*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D055815:Young Adult
chemical_list: D001323:Autoantibodies; C121001:NR2B NMDA receptor; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D016194:Receptors, N-Methyl-D-Aspartate; C059659:technetium Tc 99m bicisate; D003545:Cysteine
keywords: Autoantibody against the glutamate receptor epsilon 2; Brain perfusion SPECT; Non-herpetic limbic encephalitis; eZIS analysis