Recent discoveries make it necessary to reevaluate many of the traditional assumptions concerning sinusitis. Within the past 10 years, investigators have detailed the pathophysiology of sinusitis. Occlusion of the sinus ostia initiates the sinusitis cycle; untreated, this leads to chronic sinusitis. Anatomic abnormalities also predispose the patient to chronic sinusitis because of ostial blockage. Investigators have identified and detailed the prevalence of both aerobic and anaerobic environments within the sinuses, demonstrating that ostial blockage creates an ideal culture medium within the sinus. Keeping the ostial passageways open is essential to allow reversal of the sinusitis cycle, especially in the presence of predisposing factors.