Anatomy and pathology of the frontal sinus

The frontal sinuses are paired sinuses with significant variability. To fully understand the anatomy of the frontal sinus, it is important to understand the embryology as well as the complex and variable outflow tracts. As with other areas of the sinonasal cavity, the frontal sinuses can be affected by a variety of inflammatory as well as benign processes. However, malignant processes most often affect the frontal sinus by extension, and primary malignancies of the frontal sinus are rare. This chapter provides a review of the anatomy and embryology of the frontal sinus, followed by a description of several of the most common benign, inflammatory and malignant pathologies that involve this sinus.