The frontal intersinus septum takedown procedure: Revisiting a technique for surgically refractory unilateral frontal sinus disease

Objectives/Hypothesis: Unilateral frontal sinus obstruction presents a surgical challenge when outflow tract osteoneogenesis or dense scarring is present. Frontal sinus obliteration is often employed as a last resort, but this procedure has potential long-term complications. In some cases, endoscopic modified Lothrop or unilateral drillout procedures may be effective options; however, restenosis rates are often high. Here we report our experience using frontal intersinus septum takedown (FISST) to address unilateral obstruction while preserving the opposite frontal outflow tract. Study Design: A retrospective review was performed of 12 patients with unilateral frontal sinus opacification due to irreversible frontal recess obstruction who underwent FISST. Surgical outcomes were assessed based on symptoms and computed tomography (CT) resolution of frontal sinus disease. Results: All 12 patients undergoing FISST had significant improvement in their symptoms. Ten postoperative CT scans were available for review, all showing continued patency of the interfrontal connection, and nine out of 10 with resolution of radiographic frontal sinus disease. Eleven of the procedures were performed via trephination, and one was achieved endoscopically. Conclusions: In patients with one obstructed frontal sinus and a functional contralateral sinus, removal of the intersinus septum allows for adequate sinus drainage and significant clinical improvement. The success of FISST may be surprising given knowledge of mucociliary clearance patterns, but may be effective because of the naturally dependent position of the frontal sinus ostium.