Revista chilena de radiología
versión On-line ISSN 0717-9308
CORONADO G, César et al. ESTIMATION OF THE ORBITAL VOLUME WITH CT IMAGES AND CAVALIERIS PRINCIPLE. Rev. chil. radiol. [online]. 2010, vol.16, n.2, pp. 59-63. ISSN 0717-9308. doi: 10.4067/S0717-93082010000200004.
Determination of the orbital volume has significance in cases such as facial injuries and lens implants where it is necessary to restore the normal position of the structures, since providing the patient with a volume-deficient orbit may result in enophthalmos. The aim of this study is to assess the volume of the orbit by using the Cavalieri s principle supplemented with sequential analysis of CT images on the computer screen. We conducted a series of CT images with a thickness of 1mm on 10 human skulls. After selection, initially random and then sequential, images were analyzed on a computer screen with a mesh test chart to determine orbital area. Once having identifed both area and thickness, we measured the volume of segments, and the total volume of the orbit was extrapolated by using a mathematical formula based on the Cavalieri s principle. Results were compared with the actual volume obtained by the displacement of fuid from printouts of the orbits. The result of this comparison suggests that the method is statistically reliable when considering that we assessed seven images of a randomly chosen orbit and then in a known sequence with a straightforward technique for orbital volume estimation.
Palabras clave : Cavalieris Principle; Computed Tomography; Images; Orbit; Volume.