Corneal ectasia is a disorder that appears just like keratoconus but develops after LASIK. It is also called secondary keratoconus oriatrogenic keratoconus. It is very rare, and its causes are uncertain. Some patients who develop ectasia after LASIK would have developed keratoconus even without LASIK surgery because of their genetic predisposition. Other patients develop it because the surgeon removed too much tissue during the procedure. Poor preoperative screening is often a factor in these cases. To prevent ectasia after LASIK, your surgeon will measure your corneal thickness before surgery. He or she should ensure that you have a minimum of 220 to 250 microns of tissue remaining after LASIK.
Corneal ectasia is very rare. Those who are at higher risk for developing ectasia include people with extreme myopia or whose eyes have an irregular preoperative shape or people who have a particularly thin cornea. It is important to note that corneal ectasia has occurred in patients with no risk factors and after LASIK procedures that appeared to be free of complications.
In its early stages, keratoconus and ectasia are often successfully managed with rigid gas permeable contact lenses. Patients often find they are able to use these lenses for many years with few problems. Intacs, tiny rings inserted into the cornea to correct nearsightedness, are also used to manage keratoconus in early stages of treatment. In more advanced cases, keratoconus may require a corneal transplant. Patients who cannot wear the rigid gas permeable contact lens may also need a transplant. Usually, corneal transplants are very successful. Unlike keratoconus, corneal ectasia is not usually progressive, so even patients who develop it do not usually require a corneal transplant.
Although infection is the most feared complication, it is extremely rare, occurring in about 1 in 10,000 surgeries done by an experienced surgeon. As with any surgery, proper technique is the best way to avoid infection. If your eye does become infected, it will likely occur during the first 48 to 72 hours after LASIK. This is why it is so important for the first week to avoid any contact with substances that may cause infection, such as eye makeup, hot tubs, and swimming pools. It is also essential to go to all of your follow-up visits, even if everything seems fine. To prevent infection, you will use antibiotic drops postoperatively for a few days to a week.