Mucosal cysts in the paranasal sinuses: long-term follow-up and clinical implications.

BackgroundAlthough mucosal cysts in the paranasal sinuses (PSMCs) are commonly detected, the long-term follow-up studies of PSMCs are sparse. This study evaluated the natural course of PSMCs and identified risk factors for the disease progression.MethodsA total of 133 subjects with PSMCs who underwent health checkup including brain magnetic resonance imaging more than two times with an interval of ≥24 months between January 2000 and December 2009 were included. The characteristics of PSMCs were analyzed on the initial and follow-up images. Nasal symptoms, smoking status, and comorbid medical conditions were evaluated using structured questionnaires and medical records.ResultsThe mean follow-up duration was 40.38 months (range, 24.0–109.8 months). The mean size of PSMCs decreased from 15.07 to 12.73 mm. Only 8.3% of subjects showed an increase in size, whereas the size of cysts was decreased or unchanged in the remaining 91.7% of subjects. Six (4.5%) subjects complained of nasal symptoms during follow-up a...