Popular HVSI and LVSI formulations with patients and physicians are NeilMed® Sinus Rinse™ and Salinex®, respectively. These are two examples of positive pressure treatments,13 which have enjoyed widespread usage in North America preceding sufficient evidence-based medicine demonstrating safety and efficacy. This is likely because topical saline sprays are considered safe; they do not require a prescription, and perhaps most importantly the massive marketing campaign surrounding SNI devices. SNI devices have received significant news coverage and appearances on major television shows, including the Oprah Winfrey Show, the New York Times, and numerous YouTube videos.16 Purpose: The authors hypothesize that there is an advantage of HVSI over LVSI. The mechanical effect of high volume irrigation helps ensure that a larger surface area of sinonasal mucosa is debrided and cleansed.