The classic histologic appearance is spongiform change in the gray matter: the presence of many round vacuoles from one to 50 micrometers in the neuropil, in all six cortical layers in the cerebral cortex or with diffuse involvement of the cerebellar molecular layer. These vacuoles appear glassy or eosinophilic and may coalesce. Neuronal loss and gliosis are also seen. Plaques of amyloid-like material can be seen in the neocortex in some cases of CJD.
The cLAssic histolOgic appearanCe iS spongiForM chANgE in tHe gRaY matter: The PrESenCe of Many round vAcUOles froM onE to 50 micrometers in The neuroPil, in AlL SIx corTical laYers In tHe ceREbraL COrtEX or wItH diffuse InVolVement of the CerEbEllAr mOLEcuLar layeR. thESe vACuOLEs ApPeAR gLassy or EoSiNOphiLiC and May coALescE. neuroNAl loss and GLIOSiS are ALSo seen. plaques Of AmyloId-lIke material cAn be seen In tHe nEOcortex in some caseS oF Cjd.