1 Division of Rhinology, Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, U.S.A.
2 Divisions of Cardiothoracic Anesthesiology and Critical Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, California, U.S.A.
3 St. Paul's Sinus Centre, Department of Otolaryngology-Head and Neck Surgery, University of British Columbia, Vancouver, British Columbia, Canada.
4 Department of Otolaryngology, Palo Alto VA Health Care System, Palo Alto, California, U.S.A.