Corneal Collagen Crosslinking with Riboflavin (CXL) and Intacs for Keratoconus, Ectasia, and Infectious Keratitis
Corneal Collagen Cross-linking with Riboflavin (CxL) is a new keratoconus and ectasia treatment that has been proven outside of the US to strengthen a weakened corneal structure. CxL is currently in US Food and Drug Administration (FDA) clinical trials.
Keratoconus is a disease of the cornea which allows the cornea to become weak and it may gradually bulge outward. Most often, this bulging is in the lower half of the cornea and first presents as astigmatism. However not all astigmatism is due to keratoconus. In mild or early stages of keratoconus (forme fruste keratoconus), eyeglasses may still correct the astigmatic vision.
Keratoconus and ectasia create an irregular cornea that can be treated with CXL and/or Intacs / Keraring / Ferrara ring inserts.
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The 30-minute corneal crosslinking treatment is performed in the doctor’s office. During the treatment, custom-made riboflavin eye drops are applied to the cornea, which is then activated by ultraviolet light. This amazingly simple process has been shown in laboratory and clinical studies to increase the amount of collagen cross-linking in the cornea and strengthen the cornea. In published European studies, such treatments were proven safe and effective in patients.
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The theory behind CXL treatment is that the fibrils of the keratoconus cornea lose their ability to link to each other.
This treatment works by increasing collagen cross-linking, which form the natural “anchors” within the cornea. These anchors are responsible for preventing the cornea from bulging out and becoming steep and irregular, as found in advanced keratoconus.
UVA light is applied in precise amounts using a specialized device with LED lights.
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Nonprofit Lasik laser eye surgery patient advocacy with network of evaluated Lasik doctors and detailed laser eye surgery information.
CXL treatment causes more cross-linking of the fibrils, making the cornea stronger.
The abnormal curvature of the cornea due to keratoconus changes the cornea�€™s refractive error producing moderate to severe blurriness of vision. As keratoconus advances, rigid gas-permeable (RGP) contact lenses maybe the only non-surgical way to achieve clear vision. If keratoconus continues to advance, scarring of the central cornea may occur.
The image shows a map of an eye with keratoconus. The off-center red and yellow area shows the forward bulging due to keratoconus.
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Approximately half of keratoconus patients have no negative lifestyle effects beyond corrective lenses. The cornea stabilizes after a few years without ever causing severe vision problems. For others, the only resolution to keratoconus has been PKP (corneal graft), with a long healing period and unpredictable refractive error. Even after corneal transplant PKP, keratoconus can reoccur in the new donor cornea. Fortunately, there are these two new methods to treat keratoconus much earlier, which are much less invasive than a corneal transplant.
An established treatment for keratoconus is Intacs. Intacs are a medical device approved by the FDA for the correction of 1.00 to 3.00 diopters of myopia (nearsighted, shortsighted) and virtually no astigmatism. Intacs inserts are the only refractive surgery procedure that adds structural integrity to the cornea. This unique attribute made Intacs an ideal treatment for keratoconus.
Intacs are clear small semicircular plastic rings of various thickness that are inserted within the cornea at its outer edges. Insertions of these rings flatten the central area of the cornea and correct myopic refractive error. A major advantage of Intacs is that no tissue is removed and there is no ablation or incision across the visual axis.
Related Topic:
Intacs
Dr Millicent M. Grim
Specialist Ophthalmologist / LASIK Specialist
MBChB (Pretoria), DTM & H (WITS), MMed (Ophth) (Pretoria)
AAO, ASCRS, ISRS (US), GMC (UK)
