Pediatric Orbital Roof Fractures: A Ratio of Orbital Dimensions Correlated to Prevalence of Fracture.

Objective  Orbital roof fractures are more likely to occur in younger children, specifically younger than 7 years. Cranium to face ratio decreases with age; however, there is no definition for measurement of the neurocranium or face. We propose using the length of the orbital roof as a measurement of the neurocranium and length of the orbital floor as a tool to estimate midface size. The purpose of this study is to test this measurement as a correlation rate of orbital roof fractures within the pediatric population. Design  This is a retrospective study. Setting  This study was done at the LeBonheur Children's Hospital. Participants  Sixty-six patients with orbital roof fractures were identified and stratified by gender and age, specifically younger than 7 years and 7 years or older. Main Outcome Measures  The main outcome measures were orbital roof length, floor length, and ratio thereof. Results  Mean orbital roof length was 43.4 ± 3.06 and 45.1 ± 3.94 mm for patients <7 and ≥7 years, respectively ( p  = 0.02). Mean orbital floor length was 41.3 ± 2.99 and 47.7 ± 4.19 for patients <7 and ≥7 years, respectively ( p  < 0.00001). The mean roof to floor ratio (RTFR) for patients <7 years was 1.051 ± 0.039 and for patients ≥ 7 years was 0.947 ± 0.031 ( p  < 0.00001). Conclusion  As children age, the relative length of the orbital roof decreases when compared with the orbital floor. The RTFR was more than 1.0 in children younger than 7 years. These differences were statistically significant when compared with children 7 years and older. This measurement shift follows the differences noted in orbital fracture patterns during childhood.