RT Journal Article
SR Electronic
T1 FDG-PET and MRI in the Evolution of New-Onset Refractory Status Epilepticus
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 238
OP 244
DO 10.3174/ajnr.A5929
VO 40
IS 2
A1 Strohm, T.
A1 Steriade, C.
A1 Wu, G.
A1 Hantus, S.
A1 Rae-Grant, A.
A1 Larvie, M.
YR 2019
UL http://www.ajnr.org/content/40/2/238.abstract
AB BACKGROUND AND PURPOSE: New-onset refractory status epilepticus is a clinical condition characterized by acute and prolonged pharmacoresistant seizures without a pre-existing relevant neurologic disorder, prior epilepsy, or clear structural, toxic, or metabolic cause. New-onset refractory status epilepticus is often associated with antineuronal antibodies and may respond to early immunosuppressive therapy, reflecting an inflammatory element of the condition. FDG-PET is a useful diagnostic tool in inflammatory and noninflammatory encephalitis. We report here FDG-PET findings in new-onset refractory status epilepticus and their correlation to disease activity, other imaging findings, and outcomes.MATERIALS AND METHODS: Twelve patients who met the criteria for new-onset refractory status epilepticus and who had FDG-PET and MR imaging scans and electroencephalography at a single academic medical center between 2008 and 2017 were retrospectively identified. Images were independently reviewed by 2 radiologists specialized in nuclear imaging. Clinical characteristics and outcome measures were collected through chart review.RESULTS: Twelve patients underwent 21 FDG-PET scans and 50 MR imaging scans. Nine (75%) patients were positive for autoantibodies. All patients had identifiable abnormalities on the initial FDG-PET in the form of hypermetabolism (83%) and/or hypometabolism (42%). Eight (67%) had medial temporal involvement. All patients (n = 3) with N-methyl-D-aspartic acid receptor antibodies had profound bilateral occipital hypometabolism. Initial MR imaging findings were normal in 6 (50%) patients. Most patients had some degree of persistent hyper- (73%) or hypometabolism (45%) after immunosuppressive therapy. FDG-PET hypometabolism was predictive of poor outcome (mRS 4–6) at hospital discharge (P = .028).CONCLUSIONS: Both FDG-PET hypometabolism and hypermetabolism are seen in the setting of new-onset refractory status epilepticus and may represent markers of disease activity.ALEautoimmune limbic encephalitisEEGelectroencephalographyGABA-Bγ-aminobutyric acid BLGI1leucine-rich glioma inactivated 1NMDAN-methyl-D-aspartateNMDA-RN-methyl-D-aspartate receptorNORSEnew-onset refractory status epilepticusVGKCvoltage-gated potassium channel