title: Incidence, ocular findings, and systemic associations of ocular coloboma: a population-based study.
abstract: OBJECTIVE
  To describe the incidence, ocular findings, and systemic associations of coloboma in a population-based cohort of children.
  
  
  METHODS
  We retrospectively reviewed the medical records of pediatric (aged <19 years) patients diagnosed as having ocular coloboma from January 1, 1968, through December 31, 2007, as residents of Olmsted County, Minnesota.
  
  
  RESULTS
  Thirty-three children were newly diagnosed as having ocular coloboma (annual incidence, 2.4 per 100,000 residents <19 years old; prevalence, 1 in 2077 live births). Median patient age at diagnosis was 3.9 months (range, 2 days to 18.4 years), and 22 patients (67%) had unilateral involvement. Twelve patients (36%) had involvement of the anterior segment only, 13 (39%) of the posterior segment only, and 8 (24%) of both. During median ophthalmologic follow-up of 9.2 years (range, 13 days to 35.9 years), 19 patients (58%) had other ocular disorders, including amblyopia in 11 (33%) and strabismus in 10 (30%). During median medical follow-up of 16.8 years, 22 patients (67%) were diagnosed as having a nonocular disorder, including abnormal development in 12 (36%) and CHARGE (coloboma, heart defects, choanal atresia, retarded growth and development, genital abnormalities, and ear anomalies) syndrome in 4 (12%).
  
  
  CONCLUSIONS
  Ocular coloboma occurred in 1 in 2077 live births. More than half of the patients were diagnosed as having an ocular disorder other than coloboma, including strabismus and amblyopia in approximately one-third. Two-thirds of patients were diagnosed as having a nonocular disorder, including CHARGE syndrome in 1 in 8 patients.
authors.affiliation: Mayo Clinic College of Medicine, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA.
authors.forename: Kelly M
authors.initials: KM
authors.lastname: Nakamura
authors.forename: Nancy N
authors.initials: NN
authors.lastname: Diehl
authors.forename: Brian G
authors.initials: BG
authors.lastname: Mohney
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D000869:Anterior Eye Segment / Q000002:abnormalities*; D002648:Child; D002675:Child, Preschool; D003103:Coloboma / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008910:Minnesota / Q000453:epidemiology; D057972:Posterior Eye Segment / Q000002:abnormalities*; D012189:Retrospective Studies; D017678:Sex Distribution