OBJECTIVE: To determine if a short 10-minute video of either CT images (Video1: V1) or CT and endoscopic surgical videos (Video 2: V2) could be used to improve sinonasal anatomy knowledge in medical students (Med) and otolaryngology residents (OtoR). BACKGROUND: YouTube is a widely used platform for surgical training, yet many educational videos are of poor quality. We developed and validated two 10-minute narrated videos of sinus anatomy, the first (V1) incorporated CT images of critical structures while the second (V2) combined CT images and surgical endoscopic video. In tandem, we developed a sinonasal assessment used to test sinonasal anatomy, surgical landmarks, and situational awareness. METHODS: We performed a multicenter, randomized IRB-approved educational study evaluating the efficacy of the V1 and V2 videos by comparing pre-test (PrT) and post-test (PoT) scores in Med and OtoR subject groups. Subjects then watched the alternate video and preferences were assessed. RESULTS: A total of 30 Med and 37 OtoR successfully completed the study at 6 different institutions. There were significant differences in pre-test knowledge with OtoR scoring higher than Med in all 3 pre-test subdomains [(S1: 4.3 v s2.9, CONCLUSIONS: Short, validated videos significantly improve sinonasal education and should be incorporated in modern training programs.