"T1: low signal"
"T2/FLAIR: high signal in the basal ganglia (including the substantia nigra), midbrain, thalamus, cerebral peduncle and/or temporal cortex"
"T1 C+ (Gd): leptomeningeal and focal patchy enhancement"
"DWI/ADC: isointense without restriction of ADC"
"Encephalitis lethargica, also known as von Economo encephalitis, is a rare disease of unknown aetiology that affects the midbrain and basal ganglia. Modern cases of encephalitis lethargica are sporadic and clinically heterogenous 1,3,7, and the reliability of some these diagnoses has been questioned 7."
"The exact aetiology of encephalitis lethargica is unknown, but microscopically, there is perivascular lymphocyte infiltration of the midbrain and basal ganglia 1. It is thought that there may be an immune-mediated component, possibly triggered after a viral or bacterial (e.g. Streptococcus) infection 1,7."
"FDG PET-CT: increased glucose metabolism in the basal ganglia 3"
"Sydenham chorea"
"Symptoms are initially that of a viral prodrome (e.g. pharyngitis), followed by lethargy, sleep disorder (e.g. hypersomnolence), movement disorder (e.g. parkinsonism, dystonia, oculogyric crisis), and neuropsychiatric disturbance (mutism, depression, obsessive-compulsive disorder, catatonia, apathy, conduct disorders) 1,3,7."
"Symptoms are initially that of a viral prodrome (e.g. pharyngitis), followed by lethargy, sleep disorder (e.g. hypersomnolence), movement disorder (e.g. parkinsonism, dystonia, oculogyric crisis), and neuropsychiatric disturbance (mutism, depression, obsessive-compulsive disorder, catatonia, apathy, conduct disorders) 1,3,7."
"There may be autoantibodies against basal ganglia antigens (i.e. anti-basal ganglia antibodies), found to be present in the majority of cases in two modern case series 1,3. CSF analysis demonstrates mildly elevated protein, lymphocytosis and oligoclonal bands may also be positive 1,3."