Concha bullosa is a common anatomical variation found within the nasal cavity that involves the structure known as a nasal turbinate. It is characterized by the pneumatization, or air-filling, of one of the turbinate bones, forming a hollow, air-filled sac. This variation is common, occurring in up to half of the general population, and is often an incidental finding on medical imaging. For many individuals, this structure does not cause any problems and remains asymptomatic. When it is large enough to interfere with normal nasal function, however, concha bullosa can be the source of chronic breathing difficulties and sinus issues.
Understanding the Nasal Anatomy and Location
The nasal turbinates, also called conchae, are curved, bony structures located inside the nasal passages that are covered by a layer of soft tissue. There are three pairs of turbinates—superior, middle, and inferior—which function to warm, humidify, and filter the air you breathe before it reaches the lungs. This process is accomplished by increasing the surface area within the nose and directing airflow.
Concha bullosa most frequently affects the middle turbinate, which is the structure positioned between the superior and inferior conchae. The condition represents an expansion of the middle turbinate bone due to the presence of an ethmoid air cell that has grown into the concha.
The air pocket within the middle turbinate can vary significantly in size and location, a factor that determines its clinical importance. Radiologists classify the variation based on the area of pneumatization within the turbinate. Types include the lamellar type, where only the vertical plate of the bone is air-filled, the bulbous type, or an extensive type where the entire structure is pneumatized.
Symptoms and Functional Impact
While most cases of concha bullosa are asymptomatic, a sufficiently large air-filled turbinate can lead to chronic functional problems within the nose. The most frequent complaint is chronic nasal obstruction or congestion, often felt primarily on one side of the nose if the condition is unilateral. This congestion is persistent and typically does not improve with standard cold or allergy remedies.
The enlarged turbinate can physically press against the nasal wall, leading to pressure-related symptoms. This pressure can manifest as facial pain or headaches, sometimes called contact headaches, which are concentrated around the nose and cheeks. These symptoms arise because the contact point irritates the lining of the nasal passage.
Furthermore, a large concha bullosa can obstruct the narrow drainage pathways of the sinuses. Specifically, it may block the osteomeatal complex, the common channel for the frontal, maxillary, and anterior ethmoid sinuses to drain mucus. When this pathway is blocked, mucus accumulates in the sinuses, creating an environment conducive to infection. This mechanical obstruction is why a symptomatic concha bullosa is associated with recurring episodes of rhinosinusitis.
Diagnosis and Management Strategies
The diagnosis of concha bullosa is most accurately confirmed through medical imaging, specifically a Computed Tomography (CT) scan of the sinuses. Unlike a standard physical examination, a CT scan provides detailed cross-sectional images of the bony structures and air-filled cavities inside the nose. The air-filled sac of the concha bullosa appears distinctly dark on the scan, allowing the physician to clearly visualize its size and the extent of its contact with surrounding structures.
This imaging is necessary to determine if the anatomical variation is truly the source of a patient’s symptoms or if other issues are present, such as a deviated nasal septum or chronic sinus inflammation. Treatment is only advised for patients who are experiencing noticeable symptoms like persistent obstruction or recurrent infections. For those without symptoms, no treatment is required.
The primary management strategy for a symptomatic concha bullosa is surgical reduction. This procedure is typically performed using an endoscopic approach, meaning a small camera and instruments are inserted through the nostrils. The surgical goal is to reduce the size of the enlarged turbinate, which restores the proper airflow through the nasal passage and reopens the blocked sinus drainage pathways.
One common surgical technique involves removing the lateral wall of the air-filled pocket while preserving the medial wall of the turbinate. This process allows the turbinate to collapse inward, effectively decreasing its volume without completely removing the entire structure. By reducing the size and removing the internal air cell, the procedure alleviates the mechanical obstruction and prevents the recurrence of sinus issues caused by poor drainage.