For decades, patients with advanced keratoconus faced limited treatment options. Glasses and contact lenses could help in the early stages, but once the condition progressed, many patients were left with only one surgical path: a corneal transplant. While corneal transplantation remains a life-changing procedure for many, it is invasive, carries risks, and requires a lengthy recovery.
Today, an innovative approach is reshaping the way ophthalmologists address keratoconus: Corneal Tissue Addition Keratoplasty (CTAK). Developed right here at the Cornea and Laser Eye Institute, CTAK offers a new option for patients that preserves much of the natural cornea while still restoring vision. In this article, we’ll explore what the CTAK procedure is, how it compares to other corneal transplantation types, and why it represents an important step forward in eye surgery.
What Is CTAK?
Corneal Tissue Addition Keratoplasty (CTAK) is a relatively new surgical technique designed to treat keratoconus without requiring a full transplant. Unlike traditional penetrating keratoplasty, where the central cornea is completely replaced, the CTAK procedure involves adding a custom-shaped, sterilized corneal tissue inlay made from donor tissue into the patient’s existing cornea.
By reinforcing and reshaping the cornea rather than removing it, CTAK eye surgery reinforcesthe structure of the cornea, improves vision, and reduces irregular astigmatism. CTAK allows the surgeon to maintain the patient’s natural corneal tissue, which can lead to a faster recovery and a lower risk of rejection compared to traditional corneal transplant techniques.
CTAK for Keratoconus
Keratoconus occurs when the cornea progressively thins and bulges outward, distorting vision. In advanced stages, glasses and contact lenses cannot adequately correct vision, and historically, a penetrating keratoplasty (PK) — a full-thickness corneal transplant — was the most common surgical solution.
CTAK keratoconus treatment represents a significant shift in philosophy. Instead of replacing the entire cornea, the surgeon strategically inserts donor tissue to reinforce weak areas. This approach:
- Maintains more of the patient’s natural cornea.
- Preserves corneal innervation and biomechanics.
- Provides a safer alternative for patients who may not yet need a full transplant.
For many, CTAK surgery bridges the gap between early interventions (like corneal crosslinking) and more invasive procedures.
How CTAK Differs From Other Corneal Transplantation Types
There are several corneal transplantation types, each with its own indications and benefits.
- Penetrating Keratoplasty (PK): A full-thickness transplant where the entire central cornea is replaced with donor tissue. While effective, it carries higher risks of rejection and requires longer recovery.
- Deep Anterior Lamellar Keratoplasty (DALK): Involves replacing only the front layers of the cornea, sparing the endothelium.
- Endothelial Keratoplasty (EK): Includes DSEK and DMEK, which replace only the inner endothelial layer, typically for conditions like Fuchs’ dystrophy.
The CTAK cornea approach is different. Instead of replacing layers, donor tissue is added to reinforce structure. Because of this, it can preserve natural corneal layers while still correcting the cone-shaped distortion of keratoconus.
Key Benefits of CTAK
- Less invasive than a full transplant — Unlike penetrating keratoplasty, CTAK does not remove the central cornea. This means the patient’s native tissue is preserved, which may improve safety and outcomes.
- Lower risk of rejection — Because the body retains most of its own corneal tissue, and CTAK utilizes irradiated cornea tissue which eliminates most of the cell structure of the donor, the immune system is unlikely to reject the donor addition.
- Preserved corneal nerves and sensitivity — Full-thickness corneal transplants often disrupt corneal nerves, leading to issues like reduced sensation and dry eye. With CTAK, the nerves remain more intact.
- Faster recovery — Patients undergoing CTAK eye surgery may return to functional vision more quickly compared to those who receive a penetrating keratoplasty.
- Potential to delay or prevent a full transplant — For many keratoconus patients, CTAK offers a middle ground — improving vision and stabilizing the cornea without committing to a more invasive transplant prematurely.
Who Is a Candidate for CTAK Surgery?
Not every keratoconus patient will be suited for CTAK surgery, but ideal candidates often include:
- Individuals with moderate to advanced keratoconus.
- Patients who want to improve vision during times that they are not wearing contact lenses.
- Patients whose corneal structure is weakened but not so damaged that a full transplant is necessary.
- People who want to preserve their natural corneal tissue for as long as possible.
Our team of ophthalmologists will evaluate factors such as corneal thickness, disease progression, and overall eye health before recommending the CTAK procedure.
CTAK vs. Penetrating Keratoplasty: Which Is Better?
Both procedures have their place in modern ophthalmology. A penetrating keratoplasty remains highly effective for patients with severe scarring or very advanced disease, but it requires a longer healing process and carries higher risks.
For patients who still have viable corneal tissue, CTAK keratoconus treatment may offer many of the benefits of a transplant with fewer drawbacks. It does not rule out a future corneal transplant if needed, making it a strategic first step in surgical care.
The Future of Corneal Surgery
As surgical techniques evolve, preserving the patient’s natural tissue whenever possible has become a guiding principle. Corneal tissue addition keratoplasty reflects this trend — strengthening rather than replacing, preserving rather than discarding.
For patients living with keratoconus, this means more options, better safety, and hope for improved vision without immediately resorting to a full transplant.
If you’re interested in learning whether CTAK surgery may be right for you, we invite you to schedule a consultation here at the Cornea and Laser Eye Institute. As the pioneering center where corneal tissue addition keratoplasty was first developed, CLEI offers unmatched expertise in performing this innovative procedure. Not all eye surgeons have the same level of experience with CTAK, but by working with the team who helped invent it, you can feel confident knowing you’re receiving care from the true leaders in this field.
At CLEI, we’re also leaders in comprehensive keratoconus care. Whether your condition is mild or advanced, we create personalized treatment plans using our three-step approach: first, stopping disease progression; second, improving corneal shape — where procedures like CTAK may help; and third, enhancing vision. No matter where you are in your keratoconus journey, our team can guide you with the right plan for your unique needs.
