Thin section computed tomography in the evaluation of naso-ethmoidal trauma.

We reviewed the computed tomography (CT) appearances, plain film radiographs and clinical findings of 17 patients who suffered fractures of the naso-ethmoidal complex. Six patients (35%) with diplopia were noted on CT to have lateral displacement of medial orbital wall fragments into the orbit (medial wall 'blow-in' fractures) leading to displacement of the globe or extra-ocular muscles. Medial displacement of ethmoid bone fragments (medial wall 'blow-out' fractures) with medial rectus entrapment was noted in a further two cases (11%) also. Multiple associated facial fractures were seen in all but one case with CT evidence of frontal bone fracture and intracranial injury in 12 (70%) patients. CT was judged to add valuable information to clinical findings and plain film radiography and was especially helpful where marked soft tissue swelling precluded detailed physical examination of the naso-orbital region. The CT features of naso-ethmoidal trauma are illustrated and discussed and the advantages of CT in the pre-operative evaluation of such injuries are emphasised.