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Computerized tomography (CT) of the brain has been available since 1973 and has changed neurological, neurosurgical and radiological practice beyond recognition. A rapid growth of literature has documented it role in the diagnosis of intracranial hematoma, cerebral atrophy, brain tumor, orbital lesions and postoperative tumor evaluation. This computerized method of image reconstruction is now also being applied to the rest of the body and to other diagnostic modalities such as isotopes and ultrasound. The initial impact of CT scanning in otolaryngology is largely in four areas: 1. Facial deformities either acquired or congenital as hypertelorism, fibrous dysplasia, ossifying fibroma and Crouzon's disease. 2. Tumors involving sinuses primarily or by secondary invasion. 3. Cerebello-pontine angle lesions as meningiomas, acoustic neuromas, and glomus jugulare tumors. The larger acoustic neuroma is well visualized by this technique rendering contrast myelography unnecessary. In CT scanning, subtle differences in position and an increase in density before contrast enhancement should allow a differentiation of angle meningiomas from acoustic neuromas; in addition, CT scanning has a very important role in the postoperative assessment of angle tumors. 4. Infections as cerebral abscess or cerebritis secondary to sinus or mastoid disease. The future holds changes that will allow much finer detail, re-orientation of the horizontal information into any plane, and much more accurate differentiation of tissue density. The principle of CT image reconstruction is being applied to both isotope and ultrasound scanning and should improve their accuracy and yield. If the rapid growth of the new technology over the past two years continues, even greater usefulness can be anticipated. [ABSTRACT FROM AUTHOR]

Conventional radiology and selective complex-motion tomography suffice for the diagnosis of isolated facial fractures. Complex facial fractures, however, require a more directed diagnostic approach, utilizing the imaging potential of computed tomography (CT). In the acutely injured but stable patient, unenhanced axial CT (preview-monitored under clinical orientation) provides the most effective, safe, reasonably rapid diagnostic examination. Direct coronal CT can also be utilized. The brain is studied by contiguous 10 mm slices; the facial skeleton is studied with contiguous 5 mm slices, which permits coronal and sagittal reformations. In suspected cervical spine injury (where direct coronal CT is contraindicated), the axial CT format above will provide essential diagnostic information and allow image reconstruction. The late complications of brain abscess and CSF leak are well imaged by CT; the latter is best assessed (during activity) by preview-controlled CT after intrathecal injection of metrizamide.

Occult disease of the skull base may present as an isolated neurogenic symptom in the absence of physical signs or radiologic findings. It therefore often remains undiagnosed until advanced. Computed tomography (CT) provides the potential for diagnostic imaging far beyond conventional radiology. Not only do current generation scanners provide exquisite bone detail, they also provide the capability of soft tissue imaging. In the past year, we have matched the diagnostic problem of occult disease of the middle fossa skull base and its foramina with the potential diagnostic imaging solution of CT. Five patients were referred with possible occult middle fossa skull base disease--all had persistent unilateral facial paraesthesia in the distribution of one of the lower two trigeminal nerve divisions (V2 V3) as their only complaint; all had previously been extensively investigated (including axial CT); all remained undiagnosed. Utilizing clinically-directed CT (based on acoustic neuroma diagnostic index of suspicion and imaging experience), 2 of the 5 patients were found to have small mass lesions involving foramen ovale. This presentation will demonstrate our experience based on image-manipulated CT, actively monitored by both radiologist and otolaryngologist.