Arachnoid Cyst Fenestration

Fenestration of arachnoid cysts is indicated in cysts that show significant increase in size or associated clinical symptoms. The size of an arachnoid cyst typically remains stable or increases over time, and associated symptoms are unlikely to resolve spontaneously. Symptoms may include headaches, craniomegaly, developmental delay, and seizures.

Surgical treatment of arachnoid cysts that are large enough to cause mass effect but that remain asymptomatic is controversial. One option is to observe these cysts, but many neurosurgeons believe that any arachnoid cyst causing significant mass effect should be treated to minimize the possibility of adverse developmental effects or the risk of subdural hemorrhage.

If initial fenestration fails or if the cyst is in an anatomic location that makes success with fenestration unlikely, a shunting procedure is indicated. Cyst-peritoneum, cyst-ventricle, or cyst-subarachnoid shunts all are possible shunting treatment options.

Most arachnoid cysts do not require treatment. Small and asymptomatic arachnoid cysts should be observed clinically without any intervention.

Incidentally found cysts that remain stable in size and do not have any associated symptoms or significant mass effect on surrounding neural structures should not be treated.