title: [Measurement of orbital development in children from birth to 6 years of age].
abstract: OBJECTIVE
  An evaluation of orbital development in children from birth to 6 years of age was conducted in order to provide normal reference values for clinical use.
  
  
  METHODS
  Retrospective cohort study. By combining multi-section helical computerized tomography (CT) imaging with a computer-aided design system (BrainLAB, Munich, Germany; iPlan Cranial Software, version 2.5), we measured the orbital volume of 100 emergency children (200 eyes), who underwent computerized tomography (CT) scanning due to mild injury in Beijing Tongren Hospital and had normal CT findings. From birth to 6 years of age, according to the age of < 1 years of age for the treatment of 0 year old group, aged 1 years old and < 2 years old for 1 year old group, and so on, divided into 7 groups. Among the 50 male and female patients, the ages are 0-6 years. All of these were in order to analyze the relationship between the age and orbital volume with unary linear correlation and regression. The comparison of orbital volume between females and males was performed using two independent t-tests. Comparisons of bilateral orbital volumes were performed using a paired t-test.
  
  
  RESULTS
  The average orbital volume of children was initially (12.57 ± 3.80) cm(3) at birth, and then increased to (19.34 ± 1.86) cm(3) at 6 years of age, with an average annual growth of 1.13 cm(3). There was a positive linear relationship between orbital volume and age in children from birth to 6 years of age, yielding the regression equation: Y (orbital volume) = 13.582 + 1.042 × X(age). There is no statistic difference on the orbital volume between boys and girls (t = 1.073, 0.533, 1.808, 1.039, 1.346, 0.983, 1.774, P > 0.05). In addition, no statistic difference was found between the left and right orbital volume (t = 1.059, P = 0.292). The growth curves for all groups almost overlapped with each other.
  
  
  CONCLUSIONS
  There is a positive linear relationship between orbital volume and age in children from 0 to 6. The bilateral orbital volumes were almost the same. There is no statistic difference on the orbital volume between boys and girls.
authors.affiliation: Department of Ophthalmology, Beijing Jishuitan Hospital, Peking University 4th Hospital, Beijing 100035, China.
authors.forename: Guang
authors.initials: G
authors.lastname: Yang
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhang
authors.forename: Qinglin
authors.initials: Q
authors.lastname: Chang
authors.affiliation: Email: ldmlily@x263.net.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Li
mesh_terms: D000367:Age Factors; D000068476:Beijing; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D017076:Computer-Aided Design; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009915:Orbit / Q000254:growth & development*; D009929:Organ Size; D012016:Reference Values; D012189:Retrospective Studies; D012737:Sex Factors; D036542:Tomography, Spiral Computed