Hydrocephalus and epilepsy

Since the introduction of ventrlculo-atrial and/or ventriculoperitoneal shu nting for hydrocephalic patients, controversies have developed regarding th e Likelihood of epileptic seizures developing as a result of the shunting i tself and/or its complications. On the other; hand, hydrocephalus is not co mmonly recognized as a cause of seizures in general, although epilepsy is r eported to be frequently associated with shunt-treated hydrocephalus, espec ially in children. Several authors have reported an increased risk of epile ptic seizures after shunt placement, but the underlying mechanisms are stil l controversial. The insult to the brain at the time of ventricular cathete r insertion, the presence of the shunt tube itself as a foreign body, the b urr hole location, the number of shunt revisions after malfunction, associa ted infection, the etiology of hydrocephalus, and associated mental retarda tion are thought to be related to the risk of epilepsy. Age at the time of initial shunt placement also seems to be an important factor. Early shuntin g is a well-known determinant of risk in shunt obstruction, and children le ss than 2 years old are consequently at a higher risk of developing epileps y than older ones. It is reported that antiepileptic drug treatment is not so reliable as might be expected. Conscientious and more sophisticated EEG recording in those children may be beneficial during follow-up. The inciden ce of seizures in shunted children is reported to be quite high, ranging fr om 20% to approximately 50%, so that neurosurgeons should pay more attentio n to the issue of epilepsy in hydrocephalic children. Although ventriculo-e xtracranial shunts have been the standard treatment for hydrocephalus for d ecades, the long-term morbidity, including postshunt epileptic seizures, ha s to be taken seriously The use of neuroendoscopic techniques when indicate d may ameliorate this problem a great deal in the future.