Effect of a topical vasoconstrictor on computed tomography of paranasal sinus disease.

Apparent ethmoid inflammation which resolved with alternation of the nasal cycle or following application of topical vasoconstrictors has been observed with magnetic resonance imaging. A similar phenomenon might occur to a lesser degree with computed tomography (CT), leading to overdiagnosis of limited sinus disease. The degree to which ostiomeatal complex disease is reversible by topical vasoconstrictors was investigated. Ten patients with histories of chronic or recurrent sinusitis underwent coronal CT studies of the paranasal sinuses before and after the application of a topical vasoconstrictor. Mucosal volume or thickness measurements were obtained from the turbinates, infundibulum, ethmoidal cells, and antrum. Vasoconstrictor application markedly reduced turbinate size and appeared to reduce mucosal thickening in the ethmoidal infundibulum. Minimal mucosal changes identified in the paranasal sinuses by computed tomography were not reversed by vasoconstrictors and therefore are likely to be pathologic.