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Evaluation of the effectiveness of computed tomography in the diagnosis of orbital tumours in ibadan, southwest Nigeria.

BACKGROUND
The orbit is a bony cavity within the skull that is composed of many structures which may undergo neoplastic transformation. Failure to diagnose the tumour and determine its extent may lead to high morbidity and mortality. The aim of this study was to evaluate the role of computed tomography in the diagnosis of orbital tumours in our centre.


MATERIALS AND METHODS
Computed Tomography images acquired from a multi-sliced CT machine, tissue diagnoses obtained from histopathology reports and patients' clinical records were reviewed. The data were analyzed and presented using frequency tables, percentages and charts as appropriate.


RESULTS
Sixty six patients made up of 34 (51.6%) males and 32 (48.4%) females were studied. The ages ranged between 1 and 80 years with a mean of 35 years. Majority (50%) of the patients were in their 4th - 6th decades of life. While secondary orbital tumours were seen in 42 (63.6%) patients, primary tumours occurred in 23 (34.8%) cases. Metastatic deposit was seen in 1 (1.6%) patient. Bone was the most commonly affected orbital tissue. The CT diagnoses of benign and malignant tumours were accurate when compared with histopathological diagnoses in 80.6% and 96.7 % of the cases respectively.


CONCLUSION
Computed Tomography is useful in characterizing the nature, precise location of a lesion within the orbit and to demonstrate the extension of the orbital lesion into contiguous structures. This study showed that Computed tomography is also a useful imaging technique in the diagnosis of orbital tumours with high concordance rate when compared with histological diagnoses.