Clear Sinus Sign on Head CT Scan: Reliable Criterion to Exclude Paranasal Sinus Fracture.

PURPOSE: The clear sinus sign has been described in facial computed tomography (CT) as an indication of the absence of fluid in the paranasal sinuses. It is a highly reliable criterion to exclude fracture involving the paranasal sinus wall. Very scarce data on this sign on head CT scan is currently available. We conducted the present study to assess the usefulness of the clear sinus sign on head CT scan to exclude paranasal sinus fracture. MATERIALS AND METHODS: A retrospective cross-sectional review of the medical records and head and facial CT images was performed for 80 trauma patients with a total of 640 paranasal sinuses. The presence and absence of paranasal sinus fracture was recorded and analyzed. RESULTS: The clear sinus sign was found in 207 paranasal sinuses (32.3%) on head CT, and none of these had a paranasal sinus fracture (P < .001). CONCLUSIONS: The presence of the clear sinus sign on head CT scans is an excellent indication for exclusion of a paranasal sinus fracture in trauma patients.