Obliterative sinusitis: An underreported clinical entity.

Obliterative paranasal sinusitis is a rare sequela and end stage of chronic rhinosinusitis, which is often overlooked on imaging. It is an exuberant form of neo-osteogenesis characterized by complete or partial obliteration of the sinus cavity by new bone formation. This article presents a series of cases of obliterative sinusitis involving the sphenoid and maxillary sinuses. It is important to comment on the presence of obliterative sinusitis in the radiology report and not confuse it for native bone, fibro-osseous lesion, or arrested pneumatization, as this may have clinical implications for patients being considered for surgery. Given its potential implications for severity of sinusitis as well as prognostic significance for outcomes following endoscopic sinus surgery, awareness and timely identification of this entity is important to guide referring clinicians.