What is the medical term for a tube that drains excessive cerebrospinal fluid from the brain to the abdomen?

The medical term for a tube that drains excessive cerebrospinal fluid (CSF) from the brain to the abdomen is referred to as a shunt. A shunt is specifically designed to redirect fluid from one area of the body to another, which is essential in conditions where CSF accumulates, leading to increased intracranial pressure. This procedure helps to alleviate pressure on the brain and prevents potential damage or complications that could arise from prolonged buildup of CSF.

When considering other options, a fistula is an abnormal connection between two structures or organs, which does not specifically serve the function of draining CSF. A catheter is a flexible tube inserted into the body to allow for the drainage of fluids or delivery of medications, but it is often used in a more general sense and not specifically to refer to the system designed for CSF drainage. A stent is a device inserted into a vessel or duct to keep it open and facilitate the flow of bodily fluids, but it is not primarily used in the context of draining CSF. Thus, the term "shunt" is the most accurate choice for this particular function.