1. Department of Ophthalmology, Hospital Raja Permaisuri Bainun, Jalan Raja Ashman Shah, 30450 Ipoh, Perak, Malaysia
2. Department of Ophthalmology, Hospital Canselor Tuanku Muhriz, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Malaysia
3. Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur, Wilayah Persekutuan Kuala Lumpur, Malaysia