night shifts and eye sight loss

Is anyone aware of night shifts only affecting the eye sight??? Could you let me know of related articles?
I am a physician hospitalist and I started night shift only work in January 2008 (12 hrs night shifts, 12 shifts a month). I am also farsighted, wearing glasses in the -7 range. My eye sight have been stable for many years and I got a visit and prescription for new glasses in December 2007 (broken frame) just prior to start night shifts only work. After 9 months of night shift only work my eyesight worsened greatly and I had another opthalmology visit in October 2008 which detected an unexplained eye loss (with normal cristallin lens and retina and pressure), with the need for a new prescription for glasses, this time in the -9 range. So I got a -2 acuity loss in 8 months, previously stable for many years, and the only new thing in my life is the starting of night only shifts in January 2008. I am otherwise healthy and take no medications. I made many searches on the web but I could not find specific article on the topic. Any help is appreciated. Thanks

[John C Hagan III, MD, FACS, FAAO]

Dear MD hospitalist:

1. You are myopic not farsighted if your RX is MINUS seven.
2. There is no way that your night shift work would cause these problems. Absolutely none. If that were the case long ago night workers would have increased rates of disease. They do not.
3. Your problem could be caused by an early cataract or corneal problems or retinal diease.
4. Intraocular pressure would not be a cause of glasses changed.

Get another opinion from another ophthalmologist.

John C. Hagan III MD FACS, FAAO, Board Certfied