Objective: This study aimed to investigate the clinical characteristics of sphenoid sinus fungus ball (SSFB) to help increase the accuracy of diagnosis and efficiency of treatment.

Methods: We retrospectively analyzed the data of 77 patients who were histopathologically diagnosed with SSFB.

Results: The mean age of SSFB patients was 52.4 years (range 25-84), and 47 patients (61.0%) were female. Compared to age-matched and sex-matched chronic rhinosinusitis (CRS) patients, headache was more common in SSFB patients (79.2%; p < 0.0001). SSFB patients also had higher prevalence of diabetes than CRS (p = 0.0420). The features of computed tomography (CT) were sphenoid sinus opacification (100%), sclerosis (93.5%), calcification (76.6%), and bone erosion (41.6%). Functional endoscopic sinus surgery (FESS) was the best treatment option, and the trans-ethmoid (n = 64, 83.1%) was the most commonly used approach. No one experienced a recurrence of SSFB in 44 successfully contacted patients. Six months after FESS, 91.0% of patients (40/44) established proper drainage in the sphenoid sinus. The recovery rates for headache and nasal symptoms were 91.7% (33/36) and 77.8% (7/9) respectively.

Conclusion: SSFB is more prevalent in older women and usually presents as unilateral headache. Diabetes is a potential risk factor for SSFB. CT findings provide evidence for diagnosis and suggestions for surgical approaches. FESS is the optimal treatment for SSFB. After FESS, most patients had good prognosis with no recurrence of SSFB. However, regular endoscopic follow-up is required due to the possibility of the postoperative closure of sphenoid ostium.

Level of evidence: 3 Laryngoscope, 133:3292-3298, 2023.