What is the cornea and why are cornea transplants important?
Those who are suffering from an eye disease and have a severely damaged cornea may be a candidate for a cornea transplant. This is a procedure in which the diseased or injured cornea is replaced with healthy donor tissue. Understanding all you can about this surgery is important before deciding whether or not to proceed. This article will shed light on the basics of cornea transplants, including the indications for surgery, the surgery itself, and the potential risks and complications. We will also provide exceptional tips on preparing for surgery and what to expect after surgery.
What is cornea?
The cornea is a dome-shaped and clear surface that covers the front of an eye and helps to protect it from dust, bacteria, and other foreign particles. It also plays an important role in focusing light, as it bends or refracts incoming light rays to provide a clear image on the retina.
The cornea comprises several layers, including the epithelium, stroma, and endothelium. The epithelium layer is a thin layer of cells on the cornea's surface that helps keep it moist and protects it from infection. The stroma is the thickest layer of the cornea and consists of collagen fibers that give the cornea its shape and strength. The endothelium is a layer of cells on the cornea's inner surface that helps pump fluid out of the stroma and keep it healthy. Together, these layers keep the cornea clear and allow light to pass through so we can see clearly.
A cornea transplant is a surgery to replace a damaged or diseased cornea with healthy donor tissue. Cornea transplants are usually done when other treatments, such as eyeglasses, contact lenses, medicine, or surgery can't relieve severe cornea damage. An eye disease called keratoconus is the most common reason for a cornea transplant. keratoconus is a progressive disorder in which the normally round shape of your cornea becomes thin and cone-shaped. This cone shape deflects light as it enters your eye, causing distorted vision.
The transplant is also called keratoplasty. Different types of transplants may be performed depending on the amount of damage to your cornea.
During a full-thickness transplant, the entire thickness of your cornea is replaced. In a partial-thickness transplant, only a portion of your cornea must be replaced. A transplant of this type is also called a lamellar keratoplasty. Several methods can be used to perform a cornea transplant, including traditional surgery and newer techniques such as Descemet’s stripping automated endothelial keratoplasty (DSAEK) and Descemet’s membrane endothelial keratoplasty (DMEK).
During the procedure, the surgeon removes the damaged central portion of your cornea and replaces it with the donor tissue. The surrounding healthy tissue is then sutured (sewn) in place. After the surgery, you will likely experience some discomfort and may need to take medication for pain relief. You will also need to use antibiotics and anti-inflammatory eye drops to help prevent infection and inflammation. Most people experience an improvement in vision within a few months after surgery. Still, it may take up to a year for vision to stabilize.
Cornea transplant surgery generally takes one to two hours. You'll likely spend two to five days in the hospital after the surgery. Most people with a cornea transplant experience improved vision within a few months to a year after surgery. But it can take longer for some people to achieve their best vision post-transplant. In some cases, additional surgery may be needed.
Cornea transplants are usually successful in improving vision and can be performed on one or both eyes. However, like any surgery, there’s a risk of complications. These may include infection, rejection of the donor tissue and uncontrolled bleeding.
Graft rejection is one of the most common problems associated with cornea transplant surgery. Graft rejection occurs when the patient's immune system recognizes the donor tissue as foreign and attempts to destroy it. While this reaction is usually mild and can be treated with medication, it can sometimes lead to serious complications, such as infection or glaucoma. Additionally, there is a small risk of serious vision loss or blindness following surgery. Other risks associated with cornea transplant surgery include bleeding, infection, and damage to the surrounding eye tissue. With proper care and follow-up, most patients who undergo cornea transplant surgery experience excellent results and regain normal vision.
Thank you for reading!
Tandon, R., Singh, R., Gupta, N., & Vanathi, M. (2019). Corneal transplantation in the modern era. Indian Journal of Medical Research, 150(1), 7. https://doi.org/10.4103/ijmr.ijmr_141_19
Tan, D. T., Dart, J. K., Holland, E. J., & Kinoshita, S. (2012). Corneal transplantation. The Lancet, 379(9827), 1749–1761. https://doi.org/10.1016/s0140-6736(12)60437-1