As she walked down the hall of the suburban Maryland federal building where she works as a medical researcher, Silvia Bacot would say, \"Hi, how are you?\" to everyone she passed, worried that if she didn\'t she might inadvertently snub someone she knew but couldn\'t see. She always sat in the front row at lectures and close to the screen in theatres. At crowded scientific meetings she tried to seem unwaveringly approachable, peering and squinting at name tags when their wearers got close enough. \"I would feel like an idiot,\" she said, referring to her practice of universal greeting. \"At scientific conferences you want to make connections, and if you can\'t see people, it\'s bad.\" Luckily her work was unaffected by her inability to see at a distance because as a bench scientist she focused on objects at close range. Bacot was frustrated that her ophthalmologist had been unable to correct her severe nearsightedness and the distortion known as astigmatism which often accompanies it. She assumed that her deteriorating eyesight was an inevitable result of ageing; her eye doctor offered no other explanation. It wasn\'t until the summer of 2010, while undergoing a work-up for laser eye surgery, that Bacot, now 38, learnt that her visual problems were not caused by the normal progression of myopia but in fact indicated something far more serious. \"I turned white as a sheet of paper,\" Bacot recalled, after corneal specialist Roy Rubinfeld told her that lasik was out of the question. \"I didn\'t even know I had anything wrong with me.\" The first time her eyesight caused problems, Bacot was 6 and had just started school in her native Costa Rica. She could not see the blackboard and began suffering from severe headaches, which her grandmother dismissed as fiction, saying that \"children do not get headaches\". But after the pain persisted, Bacot was taken to a doctor, who determined she was nearsighted and prescribed her first pair of eyeglasses. The headaches disappeared and for years she saw well with glasses. In 2004, Bacot noticed that the vision in her left eye seemed unaccountably blurry. Her eye doctor strengthened her prescription but she soon noticed that her vision was fuzzy again. \"I figured it was the best they could do,\" she said, noting that the pattern of visits to the eye doctor occurred every six months or so for six years, as her vision deteriorated and her prescription got progressively stronger. \"I settled for it because of my own ignorance.\" She tried wearing contact lenses but they were uncomfortable and her vision was poorer than with glasses. Driving, especially at night, became more difficult. At times her eyes felt swollen and Bacot developed headaches, just as she had as a child. Bacot thought laser eye surgery might be the answer. She was impressed by the experience of co-workers who had undergone lasik, which uses a laser to reshape the cornea, sharpening vision. In July 2010, she met Rubinfeld. \"He told me, ‘I have good news and bad news\',\" Bacot recalled. The bad news, she remembers him saying, was that she would not be having lasik. \"If I do it,\" he told her, \"you could lose your eyesight.\" The good news, he continued, was that her problem had a name — keratoconus — and he had a treatment, although it was experimental and therefore not covered by insurance. Keratoconus, a progressive thinning of the cornea caused by a defect in the collagen, affects about one in every 2,000 Americans, according to the National Eye Institute. The cause of the disorder is unknown, but the condition can be hereditary. In some cases, keratoconus, which causes normally rounded corneas to become cone-shaped, progressively distorting vision, results from years of wearing hard contact lenses or excessive eye rubbing. \"It used to be we\'d say to patients, ‘Boy, I hope you don\'t get worse\',\" Rubinfeld said, noting that corneal transplants have a long and sometimes difficult recovery period. For the past three years, however, eye surgeons in the United States, Rubinfeld among them, have been conducting clinical trials of a procedure widely used in Europe called corneal crosslinking. A report in the American Journal of Ophthalmology in 2010 by Italian surgeons found \"long-term stability ... without relevant side-effects\" in patients assessed four years after crosslinking was performed. \"I decided to do it,\" said Bacot, who paid $3,200 (Dh11,744) for the procedure, which was performed in August 2010. Bacot was back at work the following day; she said procedure and recovery were painless. In the past 16 months, she said, her vision has improved. \"I can see so much more clearly with my glasses, including who I\'m actually talking to,\" she said. Symptoms and signs Keratoconus is a progressive eye disease in which the normally round cornea thins and begins to bulge into a cone-like shape. This cone shape deflects light as it enters the eye on its way to the light-sensitive retina, causing distorted vision. Keratoconus can occur in one or both eyes and often begins during a person’s teens or early 20s. As the cornea becomes more irregular in shape, it causes progressive nearsightedness and irregular astigmatism to develop, creating additional problems with distorted and blurred vision. Glare and light sensitivity also may occur. –www.allaboutvision.com