Case 119. 

Measles encephalitis (subacute sclerosing panencephalitis) (8 y-o M)
　 　 　 　
　 Brain lesion featured by progressive mental retardation and myoclonus (history of measles in infancy) 　
　 　 　 　

　

 　 NP antigen of measles virus is demonstrated in the nuclear inclusions in oligodendroglia (immunostaining).