Table 3.1 Morphological changes that may been seen in the CNS with advancing age.

Reduced brain mass
Reduced number of neurones
Enlargement of the ventricles
Increased lipofuscin deposition in neurones
Leptomeningeal thickening
Reduced number (denudation) of dendritic spines
Astrocyte hypertrophy (gliosis)
Argyrophilic (senile) plaque formation
Corpora amylacea formation
Perivascular haemorrhage is reported to be common in very old dogs