MRI imaging was most commonly ranked as the most important examination (median: 1), followed by CSF analysis (median: 3), inflammation parameters in blood, immunology in the blood (ANA, ENA, ds-DNA, ANCA, antiphospholipid antibodies, rheumatoid factor, complement system components and activation) (median: 4 both), conventional angiography, CSF immunology (encephalitis-associated antibodies) (median: 5 both) and lastly cranial CT (median: 6). This evidence concerns the gene BTG3 and viral encephalitis.