MATTHEW PERRONEWASHINGTON (AP) ¿ The Food and Drug Administration announced plans Thursday to study the scope of problems connected with laser eye-correcting surgery, which include blurred vision and dry eyes. The FDA says it will work with the National Eye Institute and the Department of Defense to determine the percentage of patients who experience negative side effects following surgery. The first phase of the project is already under way, with plans for an online questionnaire to help patients gauge their quality of life following surgery, according to an FDA statement. The project will also include a clinical trial tracking patients who undergo the procedure, which is expected to conclude by 2012. "This study will enhance our understanding of the risks of Lasik and could lead to a reduction in patients who experience adverse effects," said Dr. Jeffrey Shuren, the acting head of FDA's medical device division. An estimated 6 million Americans have undergone Lasik surgery, which permanently reshapes the cornea, a clear layer covering the eye. There are no guarantees of 20/20 vision and the long-term safety of the procedure is still unknown.