title: Computed tomographic measurements of orbital entrance dimensions in relation to age and gender in a sample of healthy Iranian population.
abstract: OBJECTIVE
  To determine the dimensions of orbital entrance in unaffected bony orbit by computed tomography (CT) in a sample of Iranian population.
  
  
  METHODS
  Radiologic features of 120 patients were gathered using standardized skull protocol by CT scan. We measured the distance between anterior lacrimal crest and orbital border of zygomatic bone, termed width, and the distance between the plane passing through the anterior orbital entrance to optic canal, termed depth, using horizontal sections of skull base CT scan. Sagittal sections were used to demonstrate the height, the distance between frontal and maxillary bone. Orbital index (height/width *100) was then calculated.
  
  
  RESULTS
  The mean values of orbital width, height, and depth were 28.49 ± 2.35 mm, 32.14 ± 1.57 mm, and 38.84 ± 3.90 mm, respectively. There was a significant difference in height (P = 0.001), depth (P = 0.004), and width (P = 0.012) between the right and left orbits. The mean value of the orbital index was 88.65 ± 8.90 mm in this population.
  
  
  CONCLUSIONS
  The orbital index of this sample Iranian people is Mesoseme according to our study results, the expected characteristic of the white race. The right orbits are determined to be larger than the left ones.
authors.affiliation: Arak University of Medical Sciences, Arak, Iran.
authors.forename: Zoha
authors.initials: Z
authors.lastname: Khademi
authors.affiliation: Arak University of Medical Sciences, Arak, Iran.
authors.forename: Parvindokht
authors.initials: P
authors.lastname: Bayat
keywords: Computed tomography (CT) scan; Orbit; Orbital index; Skull protocol