- Correspondence to Dr Chao Qu, Department of Ophthalmology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, 32 Road West 2, the First Ring, Chengdu, Sichuan, 610072, China;
- Received January 24, 2014
- Revised April 5, 2014
- Accepted May 9, 2014
- First published June 11, 2014.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.