Dr. Jeffery J. Machat: Hello! I am Dr. Jeff Machat, Medical Director of Crystal Clear Vision. Today I am going to discuss the possible complications of LASIK. There are basically two types of complications; those arising from the surgical technique and those arising from your healing. Surgical complications with LASIK chiefly revolve around problems with the creation or placement of the corneal flap. There are two techniques to create the corneal flap. One involves the use of a bladed microkeratome, which is the traditional method. The second technique utilizes a femtosecond laser. The cornea is typically about 540 microns thick and the corneal flap about 100 microns thick. If you think of the cornea like a book composed of 540 pages. We open the book to page 100. We then remove about 12-15 pages for each diopter or unit of nearsightedness. The book is then closed and essentially looks untouched. If we use a blade to create the flap, the flap thickness can vary. Sometimes it is thicker; sometimes it is thinner; sometimes simply a poor quality. The laser technique is much more predictable and has much less variation. Healing complications can also be related to the corneal flap. Movement of the corneal flap during the first few days can produce wrinkles and blurred vision. This is managed by surgically relifting the flap and smoothing it. It is also possible that epithelial cells from the surface of the cornea can grow beneath the corneal flap. This is known as epithelial ingrowth. Typically this is harmless, but if significant it will require relifting the flap, usually by the end of the first month, and cleaning the cells. The most common healing problem however is dry eyes, which can produce significant and persistent irritation. All LASIK patients will have some dry eyes symptoms immediately after surgery. 95% of those patients will find their symptoms minimize or clear over six months. Both surgical and healing complications can produce irregular astigmatism, which results from corneal surface irregularity. It can reduce the quality and sharpness of vision in a very small number of patients. Severe persistent night glare, which was once one of the most feared side effects of LASIK is rarely encountered today, with the introduction of customized wavefront-based laser technologies. Although everyone experiences glare early on, the overall majority of patients find that not only does their night vision improve over the first few months of healing, but in many cases their night vision may even be better than it was preoperatively with their glasses and contact lenses. Lastly, corneal ectasia is the most feared complications with LASIK today. It is related to a preexisting genetic weakness in some corneas that is not always detectable preoperatively. This weakness can result in bulging of the cornea postoperatively. It can occur weeks, months, or even years later, and produces increased nearsightedness and astigmatism. Patients now can be treated with Collagen Cross-Linking to strengthen their corneas and possibly allow alternate methods to treat the prescription. The vision may never be perfect and may remain blurry. And in some cases a corneal transplant may even be needed. Be sure to consider these complications and discuss them with your eye doctor before moving forward with LASIK surgery.