In medicine, a shunt is a device designed to drain excess cerebrospinal fluid from the brain and carry it to other parts of the body. A one-way valve is used, which usually sits outside the skull, but beneath the skin, somewhere behind the ear. A shunt is used in cases of Hydrocephalus.

Although a shunt generally works well, it may stop working if it disconnects, becomes blocked, or it is outgrown. If this happens the cerebrospinal fluid will begin to accumulate again and a number of physical symptoms will develop, some extremely serious, like seizures.

The shunt failure rate is also relatively high and it is not uncommon for patients to have multiple shunt revisions within their lifetime.

The diagnosis of cerebro-spinal buildup is complex and requires expertise.

The term shunt is also used to describe structural defects, allowing fluids to incorrectly flow from one part of the body to another. A rather common pathological shunt is the ventricular septum defect, allowing blood to flow from the left to the right ventricle through a hole in the septum , the muscular wall between the two ventricles.

Spitz-Holter

A common pediatric shunt is the Spitz-Holter shunt. The designer of the valve, John Holter, was unable to save his son Casey but his design, the Spitz-Holter valve/shunt, has helped millions around the world since the late 1950s.

See also

• Blalock-Taussig shunt
• Shunt in electronics
• Shunt resistors in ammeters