Clinical Course of Acute Maxillary Sinusitis Documented by Sequential MRI Scanning

Abstract
A prospective study was designed to assess clinical and mucosal changes that occur during resolution of acute maxillary sinusitis. Thirteen previously healthy subjects with symptoms of acute sinusitis and radiographic opacification of at least one maxillary sinus were entered into the study and treated with amoxicillin/clavulinate potassium. Assessment of clinical symptoms, clinical examination, and magnetic resonance imaging (MRI) of the maxillary sinuses were performed at baseline and at days 3, 7, 10, 14, 21, 28 and 56 after initiation of therapy. The T2 values from the MRI scans were analyzed to approximate the more viscous and more fluid-like components of the maxillary sinus contents. After three days of antibiotic therapy, there was marked improvement in facial tenderness, thickness of nasal discharge, volume of nasal discharge, headache, and nasal congestion. Ten to 14 days of treatment were required, however, for improvement in nasal patency. MRI analysis of the volume percentage of air in the involved sinuses showed that by 10 days, only half of the opacification (fluid and thickened mucosa) had resolved. By 56 days, the sinuses were only about 80% aerated. This improvement was attributed mainly to resolution of the more fluid-like component. This study shows that: (1) tissue/fluid changes in sinusitis can be followed with MRI, and (2) although treatment of acute maxillary sinusitis generally results in clinical resolution of symptoms within one week, mucosal changes can persist for 8 weeks or more.