Objective. The spreading of acute respiratory infection into the paranasal sinuses in children is poorly defined. The main objective of this study was to evaluate the frequency and spontaneous resolution of paranasal sinus abnormalities in children with acute respiratory infection using magnetic resonance imaging (MRI).
Methods. We examined 60 children with MRI (mean age: 5.7 years) with symptoms of acute respiratory infection. Twenty-six children with major abnormalities in the first MRI scan had a follow-up MRI taken 2 weeks later.
Results. The children had had symptoms of uncomplicated acute respiratory infection for an average of 6 days before the first examination (mean duration: 6.5; standard deviation: 3.0). Approximately 60% of the children had major abnormalities in their maxillary and ethmoidal sinuses, 35% in the sphenoidal sinuses, and 18% in the frontal sinuses. The most common abnormal finding was mucosal swelling. The mean overall MRI scores correlated significantly with the symptom scores (rs = 0.3). Of the individual symptoms, nasal obstruction, nasal discharge, and fever were significantly related to the MRI scores. Among the 26 children with major abnormalities in the first MRI, the findings subsequently improved significantly (mean [standard deviation] score: 12.7 [5.6] to 5.7 [5.2]), irrespective of the resolution of symptoms.
Conclusions. These observations indicate that acute respiratory infection mostly spreads into the paranasal sinuses of children in the form of mucosal edema and that these abnormalities tend to resolve spontaneously without antimicrobial treatment.