title: Outcomes in pediatric patients with Chiari malformation Type I followed up without surgery.
abstract: OBJECTIVE
  The natural history of untreated Chiari malformation Type I (CM-I) is poorly defined. The object of this study was to investigate outcomes in pediatric patients with CM-I who were followed up without surgical intervention.
  
  
  METHODS
  The authors retrospectively reviewed 124 cases involving patients with CM-I who presented between July 1999 and July 2008 and were followed up without surgery. The patients ranged in age from 0.9 to 19.8 years (mean 7 years). The duration of follow-up ranged from 1.0 to 8.6 years (mean 2.83 years). Imaging findings, symptoms, and findings on neurological examinations were noted at presentation and for the duration of follow-up.
  
  
  RESULTS
  The mean extent of tonsillar herniation at presentation was 8.35 mm (range 5-22 mm). Seven patients had a syrinx at presentation. The syrinx size did not change in these patients on follow-up imaging studies. No new syrinxes developed in the remaining patients who underwent subsequent imaging. The total number of patients with presenting symptoms was 81. Of those 81 patients, 67 demonstrated symptoms that were not typical of CM-I. Of the 14 patients with symptoms attributed to CM-I, 9 had symptoms that were not severe or frequent enough to warrant surgery, and surgery was recommended in the remaining 5 patients. Chiari malformation Type I was also diagnosed in 43 asymptomatic patients who had imaging studies performed for various reasons. No new neurological deficits were noted in any patient for the duration of follow-up.
  
  
  CONCLUSIONS
  The majority of patients with CM-I who are followed up without surgery do not progress clinically or radiologically. Longer follow-up of this cohort will be required to determine if symptoms or new neurological findings develop over the course of many years.
authors: Department of Neurosurgery, University of Miami/Miller School of Medicine and Miami Children's Hospital, Miami, Florida 33155, USA.
authors: David
authors: D
authors: Benglis
authors: Derek
authors: D
authors: Covington
authors: Ritwik
authors: R
authors: Bhatia
authors: Sanjiv
authors: S
authors: Bhatia
authors: Mohamed Samy
authors: MS
authors: Elhammady
authors: John
authors: J
authors: Ragheb
authors: Glenn
authors: G
authors: Morrison
authors: David I
authors: DI
authors: Sandberg
mesh_terms: D001139:Arnold-Chiari Malformation / Q000150:complications / Q000473:pathology / Q000628:therapy*; D002420:Cauda Equina / Q000473:pathology; D002531:Cerebellum / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018450:Disease Progression; D004677:Encephalocele / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009422:Nervous System Diseases / Q000209:etiology; D009460:Neurologic Examination; D012600:Scoliosis / Q000150:complications; D013117:Spinal Cord Compression / Q000473:pathology; D016896:Treatment Outcome