Key points: 1. This study seeks to look at the clinical effectiveness of treating patients with CRSwNP and CRSsNP with the intra-operative use of the PROPEL implant in the frontal sinus during either functional endoscopic sinus surgery (FESS) or computer assisted sinus surgery (CASS). It seeks to assess the change in SNOT22 scores post-operatively to evaluate the change in not only physical but also psychological symptoms in a UK district general hospital. 2. Results were obtained from a sample size of 23 adult patients who had PROPEL implants inserted between September 2021 and October 2023 at N. Patients either had PROPEL mini or PROPEL Contour implants inserted. 3. Clinical improvement was measured using pre- and 3-month post-operative SNOT22 scores with a mean clinical important difference (MCID) taken as 9 (8). Post-operative follow up was at one week for review and debridement, and then at 3 months where the patients were also assessed for frontal sinus patency. 4. The average reduction in SNOT22 score was 38 (range 1-75), with an average percentage reduction of 70%. No significant complications were reported throughout the follow up period for all patients. 5. This study has been able to demonstrate that within the limitations described, the use of the PROPEL implant for frontal sinus disease may confer a clinically significant reduction in the subjective symptoms and therefore an improvement in patients’ quality of life.