Chronic Maxillary Atelectasis without Obstruction of the Maxillary Ostium - A Case Report.

Rationale: Chronic maxillary atelectasis (CMA) is assumed to be caused by negative pressure in the maxillary sinus secondary to the obstruction of the ostiomeatal complex.

Patient Concerns: A 49-year-old female patient first presented to our hospital complaining of right nasal congestion, rhinorrhoea and cheek pain.

Diagnosis: Computed tomography (CT) accidentally revealed the inward bowing of the left maxillary sinus, which is a typical sign of CMA or silent sinus syndrome despite the maxillary ostium being potent.

Treatment: We did not consider any intervention for CMA because she had no symptoms related to it.

Outcomes And Take-away Lessons: No progression was noted clinically or on CT at the 6-month follow-up. The pathogenesis of CMA in our patient was not explainable by the commonly accepted theory. Apparent hypertrophy of the left maxillary bone was confirmed on CT, thus osteitis with chronic rhinosinusitis might be the potential cause of CMA in the open maxillary sinus.