Chronic sinusitis can result from persistent allergic rhinitis, recurrent unresolved acute sinusitis, or structural blockage. If chronic sinusitis is severe enough, it will require surgery. Surgery can be as limited as a nasal polypectomy; however, usually endoscopic sinus surgery is required. ENT surgeons in our practice specialize in endoscopic sinus surgery. Patient preoperative preparation for sinus surgery includes obtaining a sinus computer tomography CT scan or preferably a landmark CT scan. Peninsula Medical Center, as well as other facilities perform these specialized CT scans. Also, the Fusion Navigation System is used in the operating room, allowing for pinpoint accuracy in identifying disease tissue and normal anatomy. This technology greatly decreases the risk of complication in the critical areas adjacent to the sinuses, such as the eyes and brain.