الفهرس 
PATHOLOGICAL CONSIDERATIONOnly 14 pages are availabe for public view
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Abstract
CT has proven to be of great value in detection of maxillary lesion. It allowed identification of
fracture sites correctly, relation of the fragments to vital structures.
The form of structural facial alteration was easily assessed, optimizing the pre-surgical plan or
reconstruction. In addition allowed simultaneous evaluation of associated brain and orbital mJunes.
In infectious processes, C.T. is used mainly to detect it’s
complications including osteomyelitis and intra-cranial extension of infection. Also C.T. easily
demonstrates, mucosal thickening, polyp formation as well as sclerosis and thickening of the sinus
walls, usually present in the infectious process. Inthis study, it was found that following the
approach proposed by P.M. Som, in 1985 although expensive but it helps to detect early tumors
of
antrum and maxilla.
In metabolic lesions, by the C.T. appearance of the bony lesion
along with the age of the patient as well as a survey for other
lesion in other sites of predilection, we can reach a diagnosis.
CT helps in differentiation between benign and malignant processes in neoplasia as
the malignant neoplasm tends to extent into various anatomical compartments with
excessive bon destruction, while a benign neoplasm does not show this picture. In benign
lesions, CT easily identify osteoma and ossifying
fibroma while in inverted papilloma, there is more bone destruction mainly of the medial wall of
the sinus.
CT helps in the diagnosis of mucocele and dentigerous cyst by
expansion of the sinus with bony erosions. It may show an impacted tooth in the dentigerous cyst or
a rim of enhancement in an infected mucocele (pyocele). High resolution computed tomography is an
ideal technique for evaluating the tumors of the maxilla and antrum, offering excellent morphologic
details of both the bones and soft tissue structures. CT can demonstrate the
tumor early in the course of illness and can be used to recognize the exact extent of a lesion,
particularly in the demonstration of soft tissue tumor in the pterygo-palatine, infra-temporal
fosse, brain and orbit. This is of particular value in assessing operability and the adequacy of
radiotherapy fields. Although the technique has proved reliable, however, because of the nature of
malignant disease, including microscopic infiltration into surrounding structures, minor errors in
assessment will continue to occur. CT plays an important role in the follow up of malignant tumors
and can be used for documenting residual or recurrent tumor accurately with high confidence level.
As for the 3D reconstruction it is very useful in imaging
traumatic lesions of the maxilla bone. It is clear that the major use of 3D imaging is in the
preoperative and postoperative assessment of posttraumatic injury to the maxilla bone. Although a
linear fracture could be easily seen by CT. When compared to thin sections axial CT scans 3D
reconstruction can be beneficial in evaluating the different structures and their relations to each
other and the extent of the fracture especially those involving multiple planes.