title: Long-term natural history of incidentally discovered cavernous malformations in a single-center cohort.
abstract: OBJECTIVE
  The aim of this study was to determine the prospective hemorrhage rate in a group of retrospectively identified patients in whom symptoms had an unclear relationship to an intracerebral cavernous malformation (ICM) or the malformation itself was an incidental finding.
  
  
  METHODS
  Patients with incidentally discovered ICMs diagnosed between 1989 and 1999 were identified from a previously published cohort. Those with ICMs having an unclear relationship with existing symptoms were also eligible for analysis. Updated clinical and radiographic data pertaining to symptomatic intracerebral hemorrhage related to the ICM or new seizures were obtained through medical chart review and mail survey. In select patients, phone calls were made and death certificates were obtained when possible. The prospective hemorrhage rate was calculated as the number of prospective hemorrhages divided by the number of patient-years of follow-up.
  
  
  RESULTS
  There were 1311 patient-years of follow-up among the 107 patients (49.5% male; mean age at diagnosis 52 years) eligible for this study. Forty-four patients died in the follow-up period, and the cause of death could be determined in 34 (77%). Two patients had a prospective hemorrhage, which was definitively related to the ICM in only one. Thus, the definitive prospective bleed rate was 0.08% per patient-year. No new seizures developed in any of the patients during the follow-up period.
  
  
  CONCLUSIONS
  The risk of prospective hemorrhage in patients presenting asymptomatically with ICM is very low. This information can be useful in managing such patients and may be most applicable to those with a single ICM.
authors.affiliation: Departments of Neurology and.
authors.forename: S Arthur
authors.initials: SA
authors.lastname: Moore
authors.forename: Robert D
authors.initials: RD
authors.lastname: Brown
authors.forename: Teresa J H
authors.initials: TJ
authors.lastname: Christianson
authors.forename: Kelly D
authors.initials: KD
authors.lastname: Flemming
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000401:mortality; D002543:Cerebral Hemorrhage / Q000209:etiology* / Q000401:mortality; D005260:Female; D020786:Hemangioma, Cavernous, Central Nervous System / Q000150:complications* / Q000175:diagnosis / Q000401:mortality; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors