Multidirectional tomography and high resolution CT in lesions of the paranasal sinuses and the pharyngeal cavity.

In 18 cases of neoplasm and 18 of inflammatory lesion of the paranasal sinuses and the pharyngeal cavity the results of high resolution CT (HRCT) were compared with multidirectional tomography. In one third of the cases HRCT gave more information than tomography. The value of HRCT lay in the demonstration of thin bony structures and in the differentiation between decalcification and destruction. Soft tissue involvement of the infratemporal fossa and the pharyngeal cavity is demonstrable at an earlier stage by CT or HRCT than with tomography; the same applies to small lesions in the paranasal sinuses and in the nasal cavity. Lesions in the sphenoid and frontal bones need additional evaluation by a lateral tomography. A.p. tomography becomes necessary if frontal HRCT scans are insufficient.