Outcome of Therapies for Arachnoid Cysts of the Head and Spine in Children

Outcome After Surgery for Intracranial Cysts

Fenestration

• Overall success: A 60% success rate is achieved, as measured by relief of symptoms and radiographic decrease in the size of the cyst. The success rate varies by age, however, and is lower in infants (24).
• Success if no hydrocephalus: The success rate may be as high as 90% in the absence of hydrocephalus, ventriculomegaly, or macrocephaly.
• Need for shunt: Reported rates of subsequent need for shunting are highly variable and range from 40–80%. In appropriately selected patients, the rates are probably 40–50%.

Shunting

• Dependency: In one study (24), 100% of patients with middle fossa cysts and hydrocephalus were shunt dependent, whereas 55% of patients with middle fossa cysts and nonspecific ventriculomegaly were shunt dependent.
• Rate revisions: 10–50% of cyst shunts require revision over the lifetime of the patient. Some patients (10% of total) may require multiple revisions.
• Survival: Average time to malfunction is 5 years.
• Risk of malfunction: Larger cysts are more likely to present with shunt malfunction, whereas smaller cysts may become obliterated after shunting and not require a long-term functioning shunt.

Outcome After Surgery for Spinal Cysts

• Majority successful: Cyst fenestration is efficacious in most cases.
• Recurrence symptoms due to local scarring: Cyst recurrence or delayed neurological deterioration may occur due to local scarring.