Epilepsy and Hydrocephalus
Epilepsy is common in people with hydrocephalus. Of individuals with shunted hydrocephalus, an estimated 20% have epilepsy (Klepper et al., 1998). Epilepsy is a brain disorder that causes unprovoked, recurring seizures. A person experiences a seizure when there is excessive and abnormal brain cell activity. This often produces uncontrolled movements, decreased responsiveness, and/or unconsciousness.
In the United States, it is estimated that 1.2% of the population has epilepsy (Zack & Kobau, 2017). For people with shunted hydrocephalus, the risk of having epilepsy is related to the type or cause of hydrocephalus and to complications of its treatment.
Past studies have shown:
- 4.5% of people with normal pressure hydrocephalus (NPH) have epilepsy (Larsson et al., 2017).
- 11% of children with spina bifida and hydrocephalus have epilepsy (Persson et al., 2006).
- Up to 35% of children with congenital hydrocephalus (diagnosed before or at birth) have epilepsy (Persson et al., 2006; Fernell et al., 1988).
- 44-70% of children with posthemorrhagic hydrocephalus of prematurity have epilepsy (Battaglia et al., 2005; Tully et al., 2016).
Some studies have compared the rates of epilepsy before and after shunt placement. Studies suggest that shunt placement is associated with epilepsy; however, this may be because individuals with more severe hydrocephalus are more likely to get shunted and also to have epilepsy (Larsson et al., 2017; Tully et al., 2016; Bourgeois et al., 1999). Factors that alter the risk for developing epilepsy include the presence of a brain malformation (excluding Chiari II), repeated brain surgeries, and surgical infection (Tully et al., 2016; Bourgeois et al., 1999).
Past studies have shown:
- Surgical infection may double the risk of developing seizures (Tully et al., 2016).
- Children who have been shunted for hydrocephalus and who have a significant cognitive delay or motor disability are more likely to develop seizures than those without cognitive or motor delays (Hoppe-Hirsch et al., 1998; Bourgeois et al., 1999).
- Seizures are not likely to occur at the time of shunt malfunction (Johnson et al., 1996).
The relationship between hydrocephalus and epilepsy can also work in the other direction: Some patients with epilepsy who undergo a surgical procedure called functional hemispherectomy develop hydrocephalus as a consequence of the surgery. A significant portion of these patients develop hydrocephalus on a delayed basis, indicating the need for long-term surveillance (Lew et al., 2013).
Most children and adults with hydrocephalus and epilepsy take medication to control the seizures; however, approximately 30% of patients fail to respond to drug treatment (Bourgeois et al., 1999). This is similar to the epileptic population in general (Laxer et al., 2014; Kwan & Brodie, 2000). For these patients, surgical management of epilepsy may be an option.
For more information on epilepsy/seizures and hydrocephalus, follow the links provided in the text.
For additional support and educational resources, we encourage you to contact the Epilepsy Foundation or the Brain Recovery Project.
This article is designed to provide helpful information on the subjects discussed. It is not intended as a substitute for treatment advice from a medical professional. For diagnosis or treatment of any medical condition, consult your doctor.