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Deep Anterior Lamellar Keratectomy or DALK is a newer advanced surgical procedure now performed by Dr. Chu that has significant advantages over a traditional corneal transplant. (DALK) Deep Anterior Lamellar Keratoplasty, is a special type of corneal transplant in which only the anterior (front) part of the cornea is transplanted. The back layer of your cornea is retained. DALK allows for less chances of corneal rejection. This surgery theoretically reduces the risk of rejection and corneal transplant failure.

In traditional corneal transplantation, the entire cornea is removed and replaced with a donor cornea. This is certainly acceptable when the entire cornea is diseased, however, many times only a portion of the cornea is affected. Diseases of corneal shape (ex. keratoconus) and often diseases of corneal clarity (ex. corneal scars) are two such examples where only a portion of the cornea may be affected. Historically, the only option to address any of these conditions was a full thickness corneal transplant. For a large percentage of patients with such problems, DALK may be an excellent alternative to the traditional corneal transplant.

In DALK, only the diseased anterior layers of the cornea are removed and the important, healthy, innermost layer of the cornea (the endothelium) is retained. This is potentially a huge advantage over the traditional corneal transplantation procedure because – by preserving the healthy endothelium – the dreaded complication of rejection and its subsequent loss of corneal clarity is less likely to occur. Rejection is the cause for a large percentage of late transplantation failures in traditional corneal transplantation. This risk is largely eliminated with the DALK procedure.

When compared to a traditional corneal transplant where a large incision into the eye is made, the successful DALK surgical risks are greatly reduced because a large incision into the eye is avoided with this new procedure. Should you or someone you know be a candidate for the DALK surgery, Dr Chu has the training and expertise to provide this service for you.

When is DALK used instead of a corneal transplant?
• Keratoconus (a disease in which there is thinning and bulging of your cornea)
• Corneal Dystrophies
• Some corneal scars not involving the deeper layers of the cornea

The DALK cornea eye surgery procedure:

The DALK eye surgery usually takes about one and a half hours to complete. Most people are able to have the surgery without using general anesthesia. The anesthesiologist will put you to sleep for about five minutes while the doctor gives some shots to completely numb the eye.

• The descemet’s membrane of the donor’s cornea are removed to prepare a donor corneal button.
• The front surface of your cornea is cut. The surgeon will then remove an 8 to 9 mm circle from the front part of your cornea and replace it with a donor cornea.
• The stromal layers are separated from the descemet’s membrane. Fluid or air is injected to separate the layers. The diseased corneal tissue is removed and the donor corneal tissue is placed with fine stitches.
• The eye is then covered with a pad or a bandage soft contact lens is used.
• Patients will have stitches in your eye for several months following surgery.