Complete unilateral maxillary sinus opacity in computed tomography.

BACKGROUND/PURPOSE: Unilateral maxillary sinus opacity can be caused by many diseases, but an exact diagnosis is difficult to make. The aim of this study was to describe the pathological conditions and clinical features of patients with unilateral maxillary sinus opacity.

METHODS: From 2004 to 2008, 830 consecutive patients underwent sinus surgery or endonasal endoscopic biopsy at an academic tertiary care center. The preoperative computed tomography (CT) images for these patients were reviewed, and 11 6 patients were identified with complete unilateral maxillary sinus opacification. We then analyzed presenting symptoms, physical examinations, specific CT findings, and pathology.

RESULTS: The most frequent diagnoses were as follows: chronic rhinosinusitis (52.6%), fungus ball (29.3%), antrochoanal polyp (2.6%), benign tumor (10.4%), and malignancy (5.1%). Fungus ball was the most common diagnosis (10/18, 55.6%) in the subgroup of patients with isolated maxillary sinus opacity without disease in the other sinuses. Nasal discharge and foul-smelling breath were more common in inflammatory disease than in neoplastic disease. Neoplastic disease was more likely to present as epistaxis; a polyp or mass revealed by nasal endoscopy; mass effect in the cheek, palate, or gingiva; and bony erosion on CT. Erosion of the maxillary posterolateral wall and extra-sinus extension suggested malignancy.

CONCLUSION: Although unilateral maxillary sinus opacity is usually inflammatory in origin, fungal sinusitis and neoplastic disorder are also likely. A careful history-taking, a thorough head and neck examination including nasal endoscopy, and CT evaluation are all imperative for reaching a correct diagnosis.