Congratulations, Angela 1082 for having no side effects.
In answer to your question, the eye is the most delicate system in the human body. The manufadturer lists eye problems as one of the side-effects. Additionally, blood clots (possibly causing arterial occlusion which causes visual impairment) is listed as a side effect. Arterial bleeding doesn't surprise me either. Blood clots may be caused by vascular bleeding. The manufacturer doesn't specify.
Now, if I may now ask a question or two of you? You specifically state that you have absolutely no side effects with Levaquin and it's not the first time you've taken it. I'm curious how a healthy 23 year old found herself here on a board and why you feel compelled to push forward your lack of symptoms and your dismissive attitude (specifically towards occular problems) to a group of people who are so obviously having pretty serious side effects?