ABSTRACT
PURPOSE: Endoscopic sinus surgery (ESS) can manipulate sinus anatomy, but with limitations due to skull base and orbit anatomy. These anatomical structures dictate the maximal extent of ESS in the frontal recess and may limit surgical extent or operative duration. This study investigates the impact of these anatomical constraints on operative time and quality-of-life (QOL) outcomes. MATERIALS AND METHODS: Patients with medically refractory chronic rhinosinusitis undergoing Draf IIa frontal sinus surgery were prospectively enrolled. Anatomic measurements of the frontal sinus anatomy were collected during computed tomography review and included: widest distance between the frontal beak and posterior table, narrowest point in the ethmoid bed, Keros height, presence of an anterior ethmoid artery on a mesentery, and presence of inter-sinus septal cells. Primary outcomes included mean operative time and improvement in SinoNasal Outcome Test (SNOT-22) survey scores. RESULTS: 63 adult participants were enrolled and followed 13.8 (5.2) months on average. The ethmoid bed mean width was 7.2 (1.4) mm, the mean distance from frontal beak to the posterior table at widest was 9.0 (2.7) mm, and mean Keros height was 5.1 (1.8) mm. 49/63 (83.1%) of participants had inter-sinus septal cells and 30/63(50.8%) had anterior ethmoid arteries on a mesentery. Mean operative time was 121.5 (44.0) min while SNOT-22 scores significantly (p<0.001) improved 26.1 (21.6) on average. Anatomic measurements were not predictive of operative time or mean QOL change (p>0.050). CONCLUSIONS: Frontal sinus surgery is an effective treatment for a range of frontal and ethmoid sinus anatomy. Further study with larger sample size and measures of more restricted anatomy might elucidate treatment limitations of ESS.