improvement in overall symptom rate and 90% cure rate for treatment of papilledema. Major complications only occurred in 3/207 people (1.4%). In the largest single series of transverse sinus stenting there was an 11% rate of recurrence after one stent, requiring further stenting. Due to the permanence of the stent and small but definite risk of complications, most experts will recommend that person with IIH must have papilledema and have failed medical therapy or are intolerant to medication before stenting is undertaken. Surgery Two main surgical procedures exist in the treatment of IIH: optic nerve sheath decompression and fenestration and shunting. Surgery would normally only be offered if medical therapy is either unsuccessful or not tolerated. The choice between these two procedures depends on the predominant problem in IIH. Neither procedure is perfect: both may cause significant complications, and both may eventually fail in controlling the symptoms. There are no randomized controlled trials to guide the decision as to which procedure is best. Optic nerve sheath fenestration is an operation that involves the making of an incision in the connective tissue lining of the optic nerve in its portion behind the eye. It is not entirely clear how it protects the eye from the raised pressure, but it may be the result of either diversion of the CSF into the orbit or the creation of an area of scar tissue that lowers the pressure. The effects on the intracranial pressure itself are more modest. Moreover, the procedure may lead to significant complications, including blindness in 1–2%. The procedure is therefore recommended mainly in those who have limited headache symptoms but significant papilledema or threatened vision, or in those who have undergone unsuccessful treatment with a shunt or have a contraindication for shunt surgery. Shunt surgery, usually performed by neurosurgeons, involves the creation of a conduit by which CSF can be drained into another body cavity. The initial procedure is usually a lumboperitoneal (LP) shunt, which connects the subarachnoid space in the lumbar spine with the peritoneal cavity. Generally, a pressure valve is included in the circuit to avoid excessive drainage when the person is erect. LP shunting provides long-term relief in about half the cases; others require revision of the shunt, often on more than one occasion—usually due to shunt obstruction. If the lumboperitoneal shunt needs repeated revisions, a ventriculoatrial or ventriculoperitoneal shunt may be considered. These shunts are inserted