ETV stoma

What it is

The ETV stoma is the opening (from the Greek for mouth) created in the floor of the third ventricle during an endoscopic third ventriculostomy. It is the new pathway through which cerebrospinal fluid flows to bypass a downstream blockage.

Understanding ETV stoma

After an ETV, CSF drains from the third ventricle through the stoma into the CSF spaces at the base of the brain, bypassing the blockage. For the ETV to keep working, the stoma must remain open (patent). In some cases, the stoma can narrow or close over time, leading to ETV failure and a return of hydrocephalus symptoms — which is one reason people who have had an ETV need follow-up and should know the warning signs. The patency of the stoma and flow through it can be assessed with imaging, including CSF flow studies. Understanding the stoma helps families see both how an ETV works and why its function is monitored over time.

Why it matters

Understanding the ETV stoma helps families see how an ETV provides drainage through a created opening, and why that opening's continued patency matters — since it can close, causing ETV failure and a return of symptoms.