Dr. Niteen Dedhia

March 20, 2018

March 20, 2018

In the early stages, when the cornea is still regular, corrective prescription glasses or soft contact lenses can help the patient. As keratoconus advances, the corneal surface becomes increasingly irregular and these options do not help adequately. Treatment options can be broadly divided into stabilizing the cone and visual rehabilitation.

Stabilizing the Cone:

As keratoconus is progressive disorder, it needs to be stabilized or progression needs to be addressed.

Age

Usually it stabilizes naturally after the age of 40 years

C3-R TREATMENT (Corneal Collagen Cross Linkage with Riboflavin)

It is a non-invasive treatment for keratoconus. It strengthens the collagen tissue which forms the fabric of cornea. It is a simple 30 to 60 minutes in-office procedure. Eye drops containing Riboflavin (Vitamin B2) are applied on the cornea and then activated By Ultra-violet light. This increases the collagen cross linking causing strengthening of cornea thereby stopping it from bulging outwards and arresting keratoconus from progressing further.

The figures above show the parallel corneal layers (white) and the collagen cross-linking (Red) which are increased after C3-R treatment.

INTACS

Intacs Rings After Implantation

Insertion of Intacs In The Eye

Intacs is a minimally invasive surgical procedure that involves insertion of two tiny, clear crescent shaped implant made of special PMMA, into the cornea. They are reversible and cannot be felt by the patient. They require no maintenance. However, glasses or contact lenses may be required after successful INTACs implantation. They have shown to improve vision and stop progression of keratoconus by flattening the cornea.

Suitability:

Intacs is ideal for adults over twenty one years of age, who suffer from keratoconus. The intacs prescription inserts are advised for patients to correct myopia and astigmatism when contact lenses are no longer suitable.

Benefits

Simple, 10-minute outpatient procedure Marked improvement in vision Removable and exchangeable.

Minimally invasive as compared to corneal transplantation .

. Delays the progression of keratoconus.

The procedure allows you to undergo a corneal transplant if required, in the future.

In severe cases, C3-R treatment can also be combined with Intacs to achieve more flattening of the keratoconus cone.

Keratoplasty (Cornea Transplantation)

Keratoplasty is a corneal transplantation surgery, where diseased cornea of patient is replaced by healthy cornea from donor eye. As the cornea is replaced by healthy tissue, progression usually stops and then the patient can be visually rehabilitated.

Visual Rehabilitation

Glasses:

Early and mild cases can be corrected with glass prescription

Contact lenses:

Rigid Gas Permeable contact lenses: They are the treatment of choice when glasses fail to help the patient. They provide a smooth refractive surface replacing the irregular cone like surface of the cornea, thus enabling the patient to see clearly.

Lens fitting in keratoconus can be a demanding and time consuming process. It requires frequent visits to a good eye specialist to get a perfect and comfortable fit.

They are the treatment of choice when glasses fail to help the patient. They provide a smooth refractive surface replacing the irregular cone like surface of the cornea, thus enabling the patient to see clearly. Lens fitting in can be a demanding and time consuming process. It requires frequent visits to a good eye specialist to get a perfect and comfortable fit. “Piggyback” Contact Lenses: Some eye doctors practice “piggyback” where a soft contact lens is first placed on cornea to give it a cushion like effect and on top of it RGP lens is fitted. Thus, it combines the best features of both lenses in the sense that it makes the wearer comfortable and at the same time gives crisp clear vision. The fitting should be perfect to ensure good oxygen permeability to the cornea as the patient will be wearing two lenses. However, with newer high oxygen permeable lenses this is not a problem.

Some eye doctors practice “piggyback” where a soft contact lens is first placed on cornea to give it a cushion like effect and on top of it RGP lens is fitted. Thus, it combines the best features of both lenses in the sense that it makes the wearer comfortable and at the same time gives crisp clear vision. The fitting should be perfect to ensure good oxygen permeability to the cornea as the patient will be wearing two lenses. However, with newer high oxygen permeable lenses this is not a problem. Hybrid Contact lenses: Some manufacturers have come up with this unique design of contact lenses where the central visual portion is made up of high oxygen permeable rigid material and peripheral anchoring portion is of soft hydrogel material. This also maximizes the best features of both lenses and improves wearers comfort as well as visual performance in keratoconic eyes.

Some manufacturers have come up with this unique design of contact lenses where the central visual portion is made up of high oxygen permeable rigid material and peripheral anchoring portion is of soft hydrogel material. This also maximizes the best features of both lenses and improves wearers comfort as well as visual performance in keratoconic eyes. Mini- Scleral Lenses these are large-diameter gas permeable contacts — large enough that the periphery and edge of the lens rest on the "white" of the eye (sclera). Because the center of lenses vaults over the irregularly shaped cornea, these lenses don't apply pressure to the eye's cone-shaped surface for a more comfortable fit. These lenses also are more stable than conventional gas permeable contact lenses, which move with each blink.

New Vistas in surgical treatment:

In the last decade, with newer surgical and technological advances in treatment modalities for keratoconus, INTACS and C3-R have shown promising & encouraging results.

LASIK Xtra

In cases of early or suspected keratoconus with refractive error, LASIK can be combined with crosslinking to give good and stable visual outcome.

Implantable Collamer Lens (ICL):

ICL is mainly used for treatment of refractive error which is not amenable to LASIK. Recently it has become popular treatment modality for visual rehabilitation in cases of stable keratoconus or after C3R. It reduces the dependence on glasses/ contact lenses and is a reversible procedure. In this procedure a thin collamer lens is inserted inside the eye which corrects the refractive error upto -18D sphere and 6 D cylinders.

Toric IOLs (Toric Intra ocular lens)

In patients with stable keratoconus requiring cataract surgery, Toric IOLs is a good option. It can correct high degree of astigmatism and patient can have better visual clarity after cataract surgery.

Corneal Transplant:

This is a surgical treatment, which is reserved for advance cases of Keratoconus, where the vision cannot be improved with glasses or contact lenses. Here the central portion of the cornea is removed and replaced with a donor cornea of similar size. Of all diseases for which keratoplasty is done, keratoconus has the best prognosis. There are three types of keratoplasty

Penetrating Keratoplasty: where all layers of central part of patient’s cornea is cut and replaced by donor cornea.

Deep anterior lamellar keratoplasty (DALK): Lamellar keratoplasty is a more advanced form of Cornea transplant. In DALK, anterior four layers of patient’s cornea is removed very carefully sparing the inner delicate layers of Descemt’s membrane and endothelium and replaced by anterior four layer of donor cornea minus Descemet’s membrane. Sparing the Descemet’s membrane, risk of rejection and complications of intraocular surgery is minimized and it offers all the advantages of penetrating keratoplasty