Paranasal Sinus Calcification

• Fungal sinusitis: Usually Aspergillus. Central in the vast majority of patients with fungal sinusitis (compared to peripheral the vast majority of those with nonfungal sinusitis). Fine punctate calcifications (compared to round or eggshell calcifications in those with nonfungal sinusitis.
• Fungus ball:
• Osteoma:
• Fibrous dysplasia:
• Fracture:
• Inverted papilloma: Actually represent residual bone, not calcification.
• Olfactory neuroblastoma: Also known as esthesioneuroblastoma. Densities represent true calcifications.
• Osteosarcoma:
• Sinolith: Much less common than rinoliths and antroliths. Antroliths originate in the maxillary sinus, whereas sinoliths are found in the frontal and ethmoid sinuses. They are thought to be dystrophic calcification or ossification caused by chronic inflammation of the paranasal sinuses.

References

• Almasi M, Andrasovská M, Koval J. Sinolith in the ethmoid sinus: report of two cases and review of the literature. Eur Arch Otorhinolaryngol. 2010 Oct;267(10):1649-52.
• Som PM, Lidov M. The significance of sinonasal radiodensities: ossification, calcification, or residual bone? AJNR Am J Neuroradiol. 1994 May;15(5):917-22.
• Yoon JH, Na DG, Byun HS, Koh YH, Chung SK, Dong HJ. Calcification in chronic maxillary sinusitis: comparison of CT findings with histopathologic results. AJNR Am J Neuroradiol. 1999 Apr;20(4):571-4.