Frontal sinusotomy is a broad term which encompasses both external and intranasal approaches to open and/or create a permanent communication from the sinus to the nose.

Endoscopic frontal sinusotomy is defined as creating a permanent opening from the frontal sinus into the nose. This simple definition includes a range from relatively simple to highly complex procedures (Weber, 2001). The complexity of endoscopic frontal sinusotomy is determined by the site of obstruction to the outflow tract or disease within the sinus, and variations in frontal and ethmoid sinus anatomy.