title: Lessons from the past: cribra orbitalia, an orbital roof pathology.
abstract: OBJECTIVE
  To define a computed tomography protocol that may be used in future clinical practice for the reliable detection and analysis of cribra orbitalia.
  
  
  METHODS
  Two osteological assemblages from the Museum of London were used to select 13 cribratous skulls and 5 non-cribratous skulls. Area of cribra orbitalia was measured using image analysis. Morphology of cribra orbitalia, orbital roof density and the associated optic canal diameter was analysed using computed tomography reconstructions.
  
  
  RESULTS
  The presence of cribra orbitalia was associated with changes in the internal diploë layer as well as the cortical bone table. A novel radiological grading system and protocol was developed to identify the pathology. A decrease in the orbital roof density by 210 Hounsfield units and a reduction in the optic canal diameter, up to 1 mm, were found to be associated with the presence of cribra orbitalia.
  
  
  CONCLUSIONS
  The occurrence of cribra orbitalia is found to be associated with stenosis of the optic canal, and could explain a proportion of cases ofoptic nerve entrapment. This study provides a guideline for radiologists and oculoplastic surgeons to help detect the presence of cribra orbitalia in suspected patients.
authors.affiliation: Division of Biomedical Sciences, St George's, University of London, UK.
authors.forename: Hasan
authors.initials: H
authors.lastname: Naveed
authors.forename: Saif F
authors.initials: SF
authors.lastname: Abed
authors.forename: Indran
authors.initials: I
authors.lastname: Davagnanam
authors.forename: Jimmy M
authors.initials: JM
authors.lastname: Uddin
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Adds
mesh_terms: D002102:Cadaver; D006801:Humans; D008131:London; D009915:Orbit / Q000000981:diagnostic imaging / Q000473:pathology*; D010164:Paleopathology; D011857:Radiographic Image Interpretation, Computer-Assisted; D012886:Skull / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*