Keratoconus - Know More About It!

Hello,

I am Dr. Vinay Agrawal, I am a cornea and ocular surface specialist. Today we will be talking about keratoconus,a problem we are seeing more and more often in our clinics now. Keratoconus is a progressive disease that can cause thinning of the cornea, causing it to bulge in front and therefore leading to a variety of visual issues. Usually, it would present at around about 20 years of age. Generally, we see it in a zone between the early teens, say 15 years onwards and can be up to 35-40 years of age. Keratoconus, as the name suggests causes the cornea to become conical, as it progresses, it can cause more and more distortion of vision leading to increase in the numbers like for example, these patients would have a minus number which keeps on increasing and along with that these cylinders keep growing up and then comes a stage, where in spite of any change in the number because of the corneal irregularity, it causes a distorted vision may be the patient may have increased glare, increased starburst, increased signs and the usual complaint of these patients is, no matter what glasses they get made, they are not able to see well.

Let’s come to what is the cause of keratoconus? Recent research has suggested that there would be an abnormality of the enzymes in the cornea of patients who present with this disease and an abnormality of these enzymes can cause the oxidative stress to increase and therefore leading to thinning of tissue and that presents the bulging of the cornea over a period of time. The other aspect of keratoconus is that it is now being more and more understood that chronic eye rubbing, exposure to ultraviolet light and chronic eye irritation can be factors that can precipitate keratoconus in a genetically predisposed individual. So therefore, the commonest instruction given to all such presenting patients is to stop eye rubbing and that is becoming the most important function as far as the patient management is concerned. Let’s now move to how do we manage patients who have shown or are now diagnosed with having keratoconus. Till about a decade back, we couldn’t really stop the progression of this disease, however now for the last ten years we are in a position to stop the progression of the disease with the treatment known as corneal collagen cross-linking, this treatment, which has become popular worldwide, achieves a very good success rate in most patients and it essentially functions by causing the strengthening of the tissue in the cornea, it is done with the help of ultraviolet light and vitamin B6 or riboflavin. When used simultaneously of they work together to induce what is known as photo-oxidation and that causes and that causes the cornea to become more strong or enhances the strength of the tissue and therefore allowing it to withstand the pressures of day to day life. Another modality that is being used to help change the shape of the curve of the cornea is intracorneal rings. These rings are sometimes used in combination with corneal collagen cross-linking to help change the curvature of the cornea. And therefore reduce the numbers in a given patient and arrest the progression of the disease.

It has been there for a pretty long time but by itself, it can not arrest the progression of the disease and that is an important part to understand that corneal collagen cross-linking is the only treatment modality that can arrest the progression of this disease. How do we improve the vision in such patients is the next question that we look at. The best method which is being devised and now with very advanced modalities is the usage of contact lenses. Usually, in early patients of keratoconus or patients with mild disease, regular soft contact lenses and glasses might be a good option but in patients with a disease which is more progressed like the moderate or the severe version, there is a variety of options of customized contact lenses that are now possible. You can use hybrid contact lenses, mini sclera contact lenses, cornea sclera lenses, corneal lenses, and scleral lenses. All of these need expertise that is available in our country and can help improve the vision of a patient to almost that of a normal patient. In addition, a variety of contact lens options also help us in fitting a different kind of cone which is individualiseable to a given patient, so customization in the true sense is now a possibility to help improve vision in the eyes of keratoconus patients. With the advances in cornea transplant, we can now do layered transplants. The treatment option known as deep anterior lamellar keratoplasty or DALK is now a preferred choice for the treatment of advanced keratoconus patients. The advantage of this method is that only the layers which are weak are replaced, therefore the risk of rejection is low and also the recovery periods are reduced significantly. Overall the management of keratoconus has improved very significantly in the last decade or so. The main advantage being the availability of corneal collagen cross-linking as a treatment modality. A variety of customized contact lenses and advances in cornea transplants have all come together to make keratoconus manageable, controllable and treatable diseases. I hope this has helped clear some of your doubts of keratoconus. If you have any further questions, please feel free to contact me through Lybrate.com or cornea transplant.net, both of which will reach me and I would be very happy to more than able to answer your questions.

Thank You!