All feline and canine seizures are not caused by epilepsy. Seizures may be caused by factors other than feline and canine epilepsy and there are quite a few of them. A seizure is a fit, convulsion, epileptic attack or paroxysm. It cannot be predicted, ends suddenly and does not occur again. Epilepsy is a brain disorder where normal electric activity is disturbed. This sends out confusing nerve impulses from the brain causing scrambled messages to the muscles resulting in uncoordinated movements.
Genetic predisposition cannot be ruled out as a possible cause since it has been observed that some breeds of dogs are more susceptible to seizures than others. It is suggested that all dogs have a seizure threshold and a dog will have a seizure when this threshold is exceeded. Dogs that have a low threshold may suffer a seizure due to stimuli like hormones imbalance, injury, fatigue or hyperventilation (an increased depth and rate of breathing greater than demanded by the body needs and can cause dizziness and disruption of nerve impulses).
Seizures caused by brain injury are the easiest to diagnose. Any injury to the brain is liable to distort the structure of the cranium. This can result in dents that may apply pressure on specific areas of the brain. The resultant disruptions in the movement of nerve impulses can distort signals that are sent to the muscles finally resulting in seizures.
Besides head trauma, brain tumors, cysts and other brain disorders too can be a cause behind canine seizures. Hydrocephalus is an accumulation of cerebrospinal fluid inside the brain. In puppies it can cause an abnormally large head and a small face. In adult dogs, the symptoms are mostly neurological. It mainly occurs when the fluid path is obstructed and the fluid is not absorbed. Hydrocephalus can cause numerous neurological disorders including canine and feline seizures.
Toxic substances, metabolic diseases, and electrolyte imbalances or abnormalities can also cause abnormal neuronal activity in the cerebrum of the brain, which can result in seizures. Metabolic disorders like diabetes, liver or kidney failure bring along with them changes in the organic processes necessary for life and some of them can cause seizure in dogs. An insulin overdose can result in abnormally low blood sugar in diabetic dogs that can lead to seizures. Liver failure restricts the supply of blood and oxygen to the brain and thus may also cause canine seizures.
Certain diseases can indirectly cause seizures. For example, Cushing’s disease is usually caused by a microscopic tumor of the pituitary gland. But in some cases it can be large enough to pressurize the brain and induce neurological disturbances including seizures.
Whatever the cause, seizures are basically caused due to distorted and confusing signals sent by the brain to the muscles. The earlier a seizure is reported to a specialist, the better it is. This is because, if left untreated seizures can lead to severe manifestations and threaten life.References: