With Deep Anterior Lamellar Keratoplasty (DALK), the front layers of the cornea (the stroma and epithelium) are removed but the innermost layer (the endothelium) is left in place. The procedure is suited to people with a healthy endothelium who are suffering from conditions that affect the other layers, such as keratoconus or corneal scarring. Traditionally, this has been treated with a full-thickness transplant; however, DALK is advantageous because the patients own endothelium is retained so the rate of graft rejection is lower and the cornea is stronger than with a full-thickness transplant.
Preparing for Surgery
Do not eat or drink anything for at least 8 hours prior to the time of surgery. Needed medications can be taken with a small sip of water. It is important to continue taking the medical eye drops (e.g. for glaucoma) that you would normally use on the same day as the surgery.
The DALK procedure usually takes about 45 minutes to complete is done with local anesthesia. The surgeon will remove an small (<1cm) circle which includes the top layers of your cornea and replace it with healthy donor tissue. Stitches will remain for up to 12 months following surgery.
Post-operative follow-up care
After surgery, the eye is patched overnight and minimal discomfort should be experienced. Standard over-the-counter pain medications can be taken, if necessary. Your surgeon may also give other medications for the eye, if indicated.
You will return to to see your doctor the later the day of surgery or the following day. The patch will be removed and your eye will be examined. You will continue preoperative antibiotic and steroid drops to prevent infection and to help with healing. This first visit after surgery will only take about 15 minutes, and is primarily to check the pressure and to verify that the donor tissue is remains in the proper position. Subsequent visits are scheduled one week and three months after surgery.
DALK and conversion to full thickness corneal transplants
Occasionally, the separation of the endothelium does not work as intended. In such cases, the surgeon can perform a full thickness corneal transplant. There is a slightly higher chance of donor tissue rejection, but the visual outcome and recovery is generally very good. Whether or not a standard corneal transplant will be required depends on your individual cornea, and your doctor will discuss this with you further.