[1] Hosp Sultanah Aminah, Dept Otorhinolaryngology Head & Neck Surg, Johor Baharu, Malaysia
[2] Lam Wah Ee Hosp, Nose & Throat Head & Neck Consultant Clin, Jelutong, Penang, Malaysia
[3] Univ Kebangsaan, Malaysia Med Ctr, Dept Otorhinolaryngology Head & Neck Surg, Kuala Lumpur, Malaysia
[4] KPJ Seremban Specialist Hosp, Nose & Throat Head & Neck Consultant Clin, Jalan Toman 1,Kemayan Sq, Seremban 70200, Negeri Sembilan, Malaysia