The use of reformatted Cone Beam CT images in assessing mid-face trauma, with a focus on the orbital floor fractures

BACKGROUND AND AIM This study aims at evaluating the reliability on specific multi-planar cone beam computer tomography (CBCT) reconstruction in the orbital floor fractures. METHODS CBCT examination of the mid-face fractures area involving the floor of the orbit was performed in a number of 93 trauma patients by two independent radiologists. Both radiologists assessed the axial, coronal and sagittal sections and also the oblique coronal and sagittal extracted sections evaluating the location of the orbital fractures, its size and displacement, the involvement of the infra-orbital foramen, herniation of fat or muscle within the maxillary sinus, the overall type of the fracture and the implication of lateral or medial orbital wall. We also registered the section that provided better confidence of both examiners in visualizing the fracture of the orbit floor and the presence of herniated soft tissue, on different reformatted sectioning. RESULTS The presence of pure fracture of the orbital floor was detected in 11% of patients. The association of the orbital fractures with the zygomatic fractures was identified in the majority of the patients. In 86% of patients the displacement of the floor of the orbit was visualized, and in almost 30% of cases more than 50% of the orbital floor was involved in the fracture. Regarding the confidence between examiners, they were more confident using the oblique sagittal CBCT reformatted images for fracture detection and bone displacement evaluation, as for the soft tissue herniation the oblique coronal sections provided the highest level of confidence. CONCLUSION Mid-face trauma involves the orbital floor in the majority of situations. CBCT allows to obtain oblique images extracted from the three dimensional (3D) data that provide high confidence level in assessing pure orbital floor fractures.