title: A population based study of intracranial arachnoid cysts: clinical and neuroimaging outcomes following surgical cyst decompression in adults.
abstract: BACKGROUND
  We have gradually adopted a liberal attitude towards surgical decompression of arachnoid cysts. This study describes the results from our institution.
  
  
  METHODS
  Long term clinical and neuroimaging results of 156 adult patients (aged > or = 16 years) operated on for arachnoid cysts in our department during the period January 1987 to September 2004 were assessed based on their medical and neuroimaging records, and on a questionnaire.
  
  
  RESULTS
  The clinical and/or neuroimaging results indicated that the cyst was successfully decompressed in all patients. 82% of patients were asymptomatic or had insignificant complaints at follow-up. 12% reported no symptom relief whereas 6% experienced worsening of symptoms. The cyst disappeared after surgery, or was reduced to < 50% of the preoperative volume, in 66% of cases. In another 24%, the postoperative volume was also reduced, but was larger than 50% of the original cyst volume. No reduction in fluid volume was observed in 10% of cases. There was no association between volume reduction and clinical improvement. A complication occurred in 26 patients (17%), all with temporal cysts, leading to reoperation in 11 patients (7.1%). In only two patients did the complication cause a permanent slight disability.
  
  
  CONCLUSIONS
  Decompression of arachnoid cysts yields a substantial clinical benefit with a low risk of severe complications.
authors.affiliation: Section for Neurosurgery, Department of Surgical Sciences, University of Bergen, and Haukeland University Hospital, Bergen, Norway. chhe@helse-bergen.no
authors.forename: Christian A
authors.initials: CA
authors.lastname: Helland
authors.forename: Knut
authors.initials: K
authors.lastname: Wester
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016080:Arachnoid Cysts / Q000175:diagnosis* / Q000453:epidemiology / Q000601:surgery*; D003388:Cranial Fossa, Posterior; D019299:Decompression, Surgical / Q000009:adverse effects; D003943:Diagnostic Techniques, Neurological; D005260:Female; D005500:Follow-Up Studies; D005625:Frontal Lobe; D006261:Headache / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D017060:Patient Satisfaction; D012086:Reoperation; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D013702:Temporal Lobe; D016896:Treatment Outcome