Incidental Sphenoid Sinus Pathosis Recognition in Cone Beam Computed Tomography

Objectives: The purpose of this study was to investigate the prevalence of radiographically recognized sphenoid sinus pathosis among patients who underwent volumetric Cone Beam Computed Tomography (CBCT) imaging for dental indications.

Methods: A retrospective radiographic evaluation of 227 dental patients was conducted. The radiographic interpretation was conducted by both a board certified oral & maxillofacial radiologist and oral & maxillofacial pathologist. The sphenoid sinus was assessed in coronal, axial and sagittal planes utilizing Xoran software^TM provided by the manufacturer with the ICAT^TM CBCT unit. Images were acquired employing 120 KV, 24mA, 20 seconds, and a field of view of 13cm providing voxel size of 0.3 mm. Non corticated dome shaped radiopacity was considered as a polyp. Partial or complete opacification of the sphenoid sinus with concomitant reactive osseous sclerosis was diagnosed as sinusitis. The anterio-posterior dimension of sella turcica was assessed in the sagittal plane for the presence of expansile lesions.

Results: Sphenoid sinus pathosis was observed in 11.9% of patients. The most common pathologies identified were sphenoid sinus polyps (7.9%), and sinusitis (3.1%). Sphenoid sinus polyps were associated with pathologies of the other sinuses in two-thirds of patients (Six had polyps in other sinuses: maxillary, ethmoid, or both). When sphenoid sinus polyps were associated with maxillary sinusitis, they were either restricted to the maxillary sinus or involved the ethmoid sinuses. Isolated sphenoid sinusitis was observed in 6 of 7 cases. One patient had concomitant ethmoid and frontal sinusitis. Additional findings included 1 pituitary adenoma and 1 erosion of the clivus.

Conclusion: Sphenoid sinus pathosis was incidentally identified in 11.9% of the CBCT scans reviewed. Patients with sphenoid sinus polyps were likely to have pathosis of the other sinuses. In contrast, the majority of patients with sphenoid sinusitis had no additional sinus involvement.