Role of Two-Dimensional Computed Tomography, Multiplanar Reconstruction and Three Dimensional Computed Tomography in the Assessment of Facial Trauma

Background: Computed tomography (CT) has become the primary imaging modality for diagnosis of facial fractures. Spiral CT further simplified diagnosis of facial trauma by allowing multiplanar reformations and three dimensional reconstructions while reducing patient motion and registration artifacts. Objective: To evaluate the role of helical CT and three dimensional reconstructions in diagnosis of different patterns of facial fractures. Subjects and Methods: From June 2003 to February 2005, One hundred patients aging from 6-64 years (including 78 males 22 females) presented with a variety of facial injuries were included in the study. All patients were referred to our CT unit from the emergency department, Suez Canal University Hospital, Ismailia. All cases underwent a spiral CT study then, the image data were manipulated and analyzed. Results: Fracture detection by two dimensional computed tomography (2D CT) and multiplanar reconstruction (MPR) together was 100% (226 of 226 fractures), fracture detection by axial 2D CT alone was 220 of 226 fractures (97.3%) but fracture detection by 3D CT alone was 183 of 226 fractures (80.9%). Two cases of cribriform plate of ethmoidal bone fracture, one case of nasal septum fracture, one case of hard palate fracture, one case of orbital roof and one case with orbital floor fracture was done by coronal reformatted images and missed on axial 2D CT images. MPR was useful or determinant in 53 of 226 fractures (23.4%) of all fractures in comparison with direct axial 2D CT. Three dimensional computed tomography (3D CT) images alone never showed any more fractures than those seen on axial and coronalreformatted images. Conclusion: Fracture detection was always superior by 2D CT but perception of fragment displacement and resulting disruption of facial symmetry was superior on 3D CT. The greatest advantage of multiplanar imaging is the improved depiction of skeletal injuries along a horizontal plane, paralleling that of axial scans. The depiction of fractures of cribriform plate of ethmoidal bone and orbital roof floor was particularly useful from a clinical viewpoint. 3D CT images should be used as a useful complementary tool.