This consists in spasmodic involuntary oscillation of the eyeball in a
horizontal, lateral, oblique or rotary direction. In animals it has been
seen in connection with poisoning and brain diseases. Johné has observed
it in horses in cerebro-spinal meningitis, Wenderhold in epilepsy, and
Möller in chloroform anæsthesia. Möller has further seen it in puppies
with congenital microphthalmos, and Siedamgrotzky in swine which had
been poisoned by herring brine.
Slight cases of functional disturbance may improve under good hygiene,
open air life and tonics, cases due to poisons may recover spontaneously
when such poisons have been eliminated, but those which depend on
structural disorder of the brain are beyond remedy.