[1] Univ British Columbia, Fac Med, Vancouver, BC, Canada
[2] Farwaniya Hosp, Ear Nose & Throat Dept, Al Farwaniyah Governorat, Kuwait
[3] St Pauls Hosp, St Pauls Sinus Ctr, Room 2600,1081 Burrard St, Vancouver, BC V6Z 1Y6, Canada
[4] Univ British Columbia, Dept Surg, Vancouver, BC, Canada