Microscopic Draf 2a frontal sinusotomy relied on direct access. However, the modern-day endoscopic approach is hindered by the anterior–posterior dimensions of the frontal recess. The nasofrontal beak, angled endoscopes, and variable frontal recess anatomy make the surgery challenging. Carolyn's window frontal sinusotomy removes the limitation of anterior–posterior dimensions and is an endoscopic version of the microscopic Draf 2a. This study aims to compare the perioperative outcomes and morbidity from endoscopic direct access Draf 2a compared to angled access Draf 2a.

Consecutive adult patients (> 18 years) seen at a tertiary referral clinic who underwent Draf 2a frontal sinus surgery using either endoscopic direct access (Carolyn’s window) or endoscopic angled instrumentation were included. Patients who underwent Carolyn's window were compared to those with angled Draf 2a frontal sinusotomy.

One hundred patients (age 51.96 ± 15.85 years, 48.0% female, follow-up 60.75 ± 17.34 months) were included. 44% of patients used Carolyn's window approach. 100% [95% CI 98.2–100%] of patients achieved successful frontal sinus patency. Both groups were comparable for early morbidities (bleeding, pain, crusting, and adhesions) and late morbidities (retained frontal recess partitions). There were no other morbidities in the early and late postoperative periods.

The endoscopic direct access Draf 2a, or Carolyn’s window, removes the anteroposterior diameter limitation. The frontal sinus patency and early and late surgical morbidities of direct access Draf 2a were comparable with the angled Draf 2a frontal sinusotomy. Surgical modifications, often with drills and bone removal, can be successfully made to enhance access in endoscopic sinus surgery without concern for additional morbidity.