An endoscopic third ventriculostomy (ETV) is a surgical procedure done on the brain to relieve pressure caused by the buildup of cerebrospinal fluid. This buildup of fluid is known as hydrocephalus, which if untreated can damage brain tissue. The endoscopic third ventriculostomy procedure involves the creation of a hole in the bottom of the third ventricle of the brain to allow cerebrospinal fluid to drain.
Cerebrospinal fluid circulates around the brain to provide nutrients to the tissue and to remove waste. This fluid passes through several open cavities in the brain known as ventricles. Any blockage in the path of this fluid causes it to accumulate, leading to hydrocephalus. A blockage can either develop in the brain of a newborn in the womb or it can be caused by a tumor in the brain.
The endoscopic third ventriculostomy is a minimally invasive procedure that does not remove a blockage in the brain but instead provides a new outlet for cerebrospinal fluid. Patients who need to have an endoscopic third ventriculostomy are first put under general anesthesia. The neurosurgeon drills a single hole in the skull and inserts a hollow instrument called an endoscope through the hole.
Surgical instruments and a camera are threaded through the endoscope to allow the neurosurgeon to view the brain and complete the surgery. The endoscope is carefully guided into the brain tissue and through an opening called the foramen of Munro. This opening leads to the third ventricle, which is in the lower center region of the brain. The neurosurgeon then punctures a hole in the bottom of the third ventricle with a blunt probe.
A balloon catheter is threaded into the endoscope and guided through the opening in the third ventricle. The balloon is inflated and serves to enlarge the hole. This opening in the ventricle allows excess cerebrospinal fluid to drain away from the brain. Once the procedure is complete, the patient should expect to stay a few days in the hospital. Recovery is typically rapid, letting patients return to normal activities in a few days.
The endoscopic third ventriculostomy is an alternative to the traditional shunt that is implanted in patients with hydrocephalus. Shunts serve to drain fluid out of the brain through a piece of tubing that extends into the abdomen. Surgery to implant a shunt is more invasive, and shunts can become infected over time. The ETV procedure is done to avoid implant of the shunt. If the ETV procedure is successful, patients should experience a decrease of pressure in the brain and fewer complications than those experienced with the shunt.