الفهرس 
ANATOMYOnly 14 pages are availabe for public view
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Abstract
Several bones contribute to the bony skeleton of the face including the mandible,which forms the only freely mobile joint of the skull. The frontal bone,maxilla, zygomata and mandible contribute most to the shape of the face.The orbits, nose and para nasal sinuses form bony cavities contained by the facial skeleton.
There has been a rising incidence of maxillofacial injuries during the past decade as a result of an increasing number of assaults and motor vehicle accidents. The maxillofacial region is one of the most complex areas of the human body.
Computed tomography is the imaging method of choice for an accurate diagnosis and for depicting the complex anatomic structures of the maxillo-facial region. Fracture lines, bony fragments, and associated skeletal deformities are clearly identified by CT scan.
Compared to the 3D CT of 1990s, the latest CT has made significant improvement thus resulting in higher accuracy of diagnosis. Multidetector CT represents a breakthrough in CT technology. It has transformed CT from a transaxial cross-sectional technique into a true 3D imaging modality that allows for arbitrary cut planes as well as excellent 3D displays of the data volume.
Previously, streak artifacts from surgical hardware made CT imaging almost impossible. With MDCT and improved reconstruction algorithms, imaging in the vicinity of hardware is much less of a problem.
MDCT is often the first and only imaging procedure a polytrauma patient will need. Each patient’s clinical findings should, however, serve as guidelines for the use of CT. Thus, the radiologist must be an active member of the trauma team.
To attain the best possible acute management of the midfacial trauma, it is imperative for the surgeon to understand the morphology and extent of the injuries CT scan images have replaced plain films as the main imaging tool to assist in the diagnosis and treatment planning for NOE fractures. CT scanning of the midface without contrast enhancement is considered the criterion standard for radiologic diagnosis of ZMC fractures and imaging of choice for Le Fort fractures.
It is important to analyze the whole face for fractures, including the entire mandible, because of the high rate of fracture of the upper and lower face when midface fractures occur.
With sagittal and coronal reconstructions, CT scans can depict all the portions of the mandible in 3 planes, but direct coronal views are always preferred. Besides identifying the fracture, it is easier to determine the degree of fragment displacement with CT scanning than with plain radiography.
CT scanning is considered to be the top choice in the imaging study for evaluating orbital trauma. The study should be performed with nonenhanced axial and coronal 3-mm cuts; multiplanar reformation sections are then performed.
Patients with traumatic injuries frequently require CT scans of the brain to evaluate intracranial injuries.
Preoperative photographs are important to document the degree of deformity. This allows the surgeon to estimate the distance of correction needed to approximate the preinjury state.
Reformatted CT images are also of high quality and have been shown to be reliable and accurate in surgical reconstructive efforts.
The use of computer-aided rendering of 3D images of the disease process or defects allows for the surgeon to manipulate the information in the preoperative setting to aid in the planning of the surgery. This preoperative planning is, in effect, a simulation of the planned surgery
Computer modeling and intraoperative navigation is a relatively new tool that can assist surgeons with reconstruction of the maxillofacial skeleton.