Change of prevalence and clinical aspects of fungal ball according to temporal difference.

Fungal ball in paranasal sinus was reported to be rare, but these days we have encountered numerous cases. We retrospectively analyzed the data of 4,485 patients with chronic rhinosinusitis (CRS) who underwent sinus surgery from 1999 to 2010. Patients were categorized into group A (patients from 1999 to 2004) and group B (patients from 2005 to 2010). We compared the prevalence and clinical aspects of fungal ball between the two groups by analyzing the medical records, PNS CT findings, surgical findings, and pathologic reports. One hundred and twelve patients were diagnosed with fungal ball during the study periods. The prevalence of fungal ball was 0.9 % (23/2,333) in group A and 4.1 % (89/2,152) in group B, showing that it increased 4.6 times over 6 years. The prevalence of underlying diseases was 21.7 % (5/23) for hypertension and 8.7 % (2/23) for diabetes in group A, and 23.6 % (21/89) for hypertension and 14.6 % (13/89) for diabetes in group B. On PNS CT examination, calcification was identified in 78.2 % (18/23) of cases in group A and 44.9 % (40/89) in group B. The most involved paranasal sinus in group A was the co-involved maxillary and ethmoid sinuses at 26.1 % (6/23), whereas, the most prevalent involved sinus in group B was the maxillary sinus at 33.7 % (30/89). We found that the prevalence of fungal ball has increased steadily each year since 2005, accompanied by changes in the clinical aspects. These facts should be kept in mind when diagnosing and treating patients with medically intractable CRS.