Bony Changes in a Unilateral Maxillary Sinus Fungal Ball

Objectives: In the paranasal sinus fungal ball (SFB), changes that occur in the underlying bone have not been well described. Recently, bacterial coinfection has been reported in patients with paranasal SFB. We evaluated whether bone changes occur in patients with unilateral maxillary SFB, and also how bacteria in an SFB affect the bony wall of the sinus. Methods: A retrospective study of patients with a unilateral maxillary SFB undergoing endoscopic sinus surgery was conducted from July 2009 to December 2015. Preoperative computed tomography images of the patients were reviewed. Wall thickness (WT) and wall density (WD) of the diseased sinus were measured and compared to the normal sinus. Specimens of the sinus aspirates were obtained during surgery for aerobic and anaerobic cultures. Results: Forty-three patients were included (mean, 55.7 ± 12.8 years). Thirty-one cultures (72.1%) were positive for bacteria. Thickening was evident in the anterior, lateral, and posterior walls of the diseased sinus. The average WT was 1.69 ± 0.45 mm on the diseased sinus and 1.14 ± 0.31 mm on the normal sinus (P < 0.001). In the diseased sinus, the difference in the average WT between the culture-positive and culture-negative groups was not significant (P = 0.44). The average WD on the diseased sinus was higher than that on the normal sinus (P < 0.001). Conclusions: Osteitic change occurred in most patients with a unilateral maxillary SFB. The presence of bacteria in sinus secretions does not greatly affect the development of osteitic changes in unilateral maxillary SFB.