A secondary middle turbinate co-existing with an accessory middle turbinate: an unusual combination of two anatomic variations.

The anatomy of the nasal cavity lateral wall is quite complex; this is where most anatomical anomalies occur. The secondary middle turbinate, a bony projection that arises from the lateral nasal wall, is a rare variation, differing from the accessory middle turbinate by its distinct developmental origin. We report on an unusual case involving a combination of these two turbinate variations. We believe that detailed knowledge of anatomical anomalies in the sinonasal tract is critical for successful clinical management and important in allowing the surgeon to perform safe functional endoscopic sinus surgery.