LAUSR

OBJECTIVE We investigated the computed tomography (CT) features of the maxillary sinus fungus ball and compared them with those of other maxillary sinus diseases. STUDY DESIGN The CT findings of 98 fungus ball lesions in 96 patients, with 35 cases of sinusitis confined to the maxillary sinus and 35 other sinus lesions confined to the maxillary sinus, were analyzed. RESULTS The most common CT feature of maxillary sinus fungus balls was calcification within the maxillary sinus (n = 77 [78.6%]), followed by complete opacification (n = 57 [58.2%]), partial opacification with an irregular surface (n = 36 [36.7%]), bony sclerosis (n = 16 [16.3%]), and partial opacification (n = 5 [5.1%]). A high probability of maxillary sinus fungus ball was found when the CT scans showed calcification within the maxillary sinus and partial opacification with an irregular surface (P < .05). CONCLUSIONS Maxillary sinus fungus balls show a higher frequency of calcification and partial opacification with an irregular surface on CT scans compared with maxillary sinusitis and other maxillary sinus lesions. Therefore, calcification and partial opacification with an irregular surface on preoperative CT scans suggest the maxillary sinus fungus ball as the first diagnostic consideration.