Onodi cell mucocele with cholesterol granuloma is more likely to cause serious optic neuropathy, compared with simple Onodi cell mucocele.

Objective: The objective is to describe the clinical features, treatments, and outcomes of a case series of patients with Onodi cell mucocele, with or without cholesterol granuloma (CG).

Material and methods: We retrospectively reviewed the medical records of eight patients diagnosed with Onodi cell mucocele at a single tertiary care university hospital in Beijing, China, between January 2017 and September 2020. Data regarding nasal symptoms, ocular symptoms, sinus computed tomography findings, treatments, histopathological results, and clinical outcomes were extracted.

Results: We identified eight patients (six men and two women) of an average age of 48.1 (range, 26-70) years. Four patients presented nasal symptoms. Three patients presented ocular symptoms. Among them, one patient experienced concurrent nasal and ocular symptoms. Two patients were diagnosed based on a physical examination in the absence of nasal or ocular symptoms. All patients underwent endoscopic sinus surgery. The pathological specimens showed mucocele in four cases and mucocele with CG in the other four cases. Among the four cases with CG, three cases presented with decreased vision. After endoscopic sinus surgery, one patient recovered completely, and two patients showed significant improvement.

Conclusion: If Onodi cell opacity is observed, especially with optic neuropathy, mucocele and CG are important differential diagnoses. The combination of mucocele and CG is more likely to promote bone destruction and cause serious optic neuropathy than simple mucocele. Endoscopic sinus surgery is appropriate. Diagnoses, treatments, and follow-up should be performed by a multidisciplinary team.