Inflammatory paranasal sinus disease in Bell's palsy demonstrated by magnetic resonance imaging.

The paranasal sinuses of 20 consecutive young adult patients with a complete Bell's palsy were investigated by magnetic resonance imaging (MRI) to obtain more information on the etiology of the disease. A high signal intensity on T2-weighted MRI was demonstrated in the paranasal sinuses, mainly the maxillary sinuses, in 12 of 20 (60%) patients in the early stage of Bell's palsy. Eleven of the 12 patients with positive MRI were followed up after 2 to 8 months (median 3 months), and in six of these, the bright signal intensity had disappeared, in two patients there was a regress, and in three patients the signal changes were persistent. The MRI findings indicate that transient inflammatory paranasal sinus disease, which may be caused by a viral and/or bacterial infection, infrequently may be associated with Bell's palsy. However, the relationship to the pathophysiologic process in Bell's palsy is still uncertain.