A population-based study of intracranial arachnoid cysts: clinical and neuroimaging outcomes following surgical cyst decompression in children.

OBJECT: If, when, and how children with arachnoid cysts should undergo surgery has been a matter of debate. In the present study the authors describe long-term clinical and neuroimaging results in children with intracranial arachnoid cysts, treated in accordance with the authors' policy of performing surgery in most of these cases.
METHODS: The study included 48 pediatric patients (age < 16 years of age) who underwent surgery for treatment of an arachnoid cyst at Haukeland University Hospital between January 1987 and September 2004. Forty-one patients underwent cyst fenestration to the basal cisterns and posterior fossa. Long-term results were assessed retrospectively on the basis of medical and neuroimaging records. Additional information was obtained by means of a check-box questionnaire completed by the patients and their parents. At their follow-up examinations, 82% of the patients had no or insignificant complaints, 14% reported no improvement, and 4% noted a worsening of symptoms. In 56% of the patients with appropriate imaging for analysis, the cyst was no longer visible on neuroimaging studies. In 23%, the postoperative fluid volume was reduced to less than 50% of the original cyst volume, and in another 19%, the volume was reduced but was larger than 50% of the original. The cyst was unchanged in only 2%. There was a significant association between a volume reduction greater than 50% and clinical improvement. Three patients (6%), all with temporal cysts, had minor complications that led to additional surgery in one patient. No complications caused permanent disability. Eight patients (17%) underwent additional surgery due to suspected or demonstrated treatment failure.
CONCLUSIONS: Most children who underwent cyst fenestration via a craniotomy experienced a good long-term outcome with no severe complications.