Lissencephaly in two Lhasa Apso dogs.

Lissencephaly, a congenital absence of cerebrocortical convolutions, was discovered in 2 Lhasa Apso dogs by clinical and pathologic evaluation. Neurologic abnormalities, which became evident within the 1st year of life, included behavioral, visual, and convulsive disorders. The neurologic abnormalities were mild or delayed in onset after birth, indicating the dog is less dependent on the cerebral cortex for sensorimotor function than is man.