Keratoconus: Causes and Symptoms

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Keratoconus and its causes

Keratoconus is a progressive, non-inflammatory corneal disease, that can lead to severe vision damages through an irregular astigmatism development and a progressive enlargement and thinning of the cornea, that goes from spherical to conical.

Normal Cornea

Keratoconus

In the past, it was common practice to classify keratoconus in phases from I to IV; the term “fruste keratoconus” represented an initial keratoconus form that was possible to spot only with a corneal topography: a normal ophthalmologic visit wasn’t enough.

Today, there are big news in keratoconus treatment. Minimally invasive keratoconus surgery, keratoconus cross linking, lamellar corneal transplant for keratoconus, laser and keratoconus, keratoconus contact lenses: an experienced ophthalmologist will advise you on the best procedure for you particular case. Dr. Badalà uses all the most modern techniques for keratoconus treatment in Milan and Catania.

Keratoconus causes

It appears most frequently in women; the causes seems to be related to the frailty of the collagen that forms the associated cornea. In some cases it can be due to repeated traumas.
It appear during teenage years and increases until it stabilizes in adulthood.

Prevention

Keratoconus is usually bilateral and once diagnosed in an eye, it is possible to ward off the worsening of the other eye by avoiding rubbing it and correcting wrong habits that can lead to repeated micro traumas, and lastly with corneal cross linking.

To slow down keratoconus progression, it is important to avoid rubbing the eyes and if it is in its initial phase, to consider cross linking. Cross linking treatment makes the cornea stronger: in this way it becomes more difficult for it to change shape. It can be performed only for specific cases.

Keratoconus symptoms

Everytime there is astigmatism that changes over time, it is mandatory to hypothesise the presense of keratoconus. Keratoconus diagnosis is made thanks to keratometry, topography, tomography and tachymetry. There are different keratoconus phases (I, II, III, IV). Corneal deformation is monitored with a special exam called “corneal topography”, essential to keep an eye on the disease progression and being able to create a customized contact lens.

The instrument project a series of bright rings and elaborates the image reflected by the cornea, outputting a printed chart with different colors in order to identify all the analyzed curvatures. Keratoconus symptoms usually consists in a variable vision quality paired with an irregular astigmatism.

Diagnosis can be confirmed with a corneal topography and a corneal pachymetry or with a corneal tomography performed with a tool like the pentacam, pretty useful in case of keratoconus.

It is best to do a few checkups:

  •  if you have relatives that have keratoconus
  • if wearing glasses you can’t reach twenty-twenty vision, even if your eyes are perfectly healthy
  • if you know to have astigmatism and you start to see not that well with your usual pair of glasses: that could be the conus changing shape.

Everytime there is a form of astigmatism that is changing over time, is it mandatory to at least think about the possibility of keratoconus. Keratoconus is classified in phases from I to IV; there is also a premature form called fruste keratoconus, that only corneal topography can spot.

Dr. Badalà, ophthalmologist in Milan and Catania, often organizes keratoconus screening campaigns, in order to facilitate early diagnosis.

Keratoconus Care

The first goal of keratoconus treatment is to stop the progression of the disease.

The first treatment is therefore to stop bad habits such as rubbing the eyes or sleeping on the stomach or on the side, which in themselves increase the risk of worsening the disease. The other therapy that has this goal is then Corneal Cross-Linking.

The second goal of keratoconus treatment is to improve vision.

For this there are many other options: the use of glasses, contact lenses of various kinds, implantation of intrastromal corneal rings (INTACS), laser to remove scars or nodules at the apex of keratoconus, and in severe cases full-thickness lamellar or perforating corneal transplantation.

Cross Linking Keratoconus

Cross linking in keratoconus has the rationale of slowing the progression of the disease. This treatment is indicated in individuals with keratoconus in the early stages to prevent worsening. The procedure aims to increase the bonds between the collagen fibrils that make up the cornea to thus make it stronger and less deformable.

The operation takes about an hour in which the cornea is imbibed with a substance called riboflavin and then the cornea is illuminated with ultraviolet A rays.

The result of corneal cross linking surgery is usually observed after several weeks or months. Improvement is described up to one year after the procedure. The aim is not to improve vision but to prevent worsening of vision with the progression of keratoconus. Cross linking in keratoconus has the rationale of slowing the progression of the disease.

This treatment is indicated in individuals with keratoconus in the early stages to prevent worsening. Cross linking surgery aims to increase the bonds between the collagen fibrils that make up the cornea to thus make it stronger and less deformable.

Cross linking with riboflavin can be done by removing the corneal epithelium (epi-OFF) or by leaving the corneal epithelium intact (epi-ON). The two methods have advantages and disadvantages that will need to be discussed in the individual case. Some level of discomfort in the eye for at least a couple of days after the procedure is to be expected.

Possible complications of treatment include ultraviolet damage to the cornea, lens, and retina, so when keratoconus is advanced and the cornea is very thin, treatment is contraindicated.

Contact lenses for keratoconus

It is first necessary to dispel a very common myth, that contact lenses slow the progression of keratoconus.

Contact lenses do not slow the progression of keratoconus they only serve to see better. There are different types, soft, rigid, semi-rigid, variable geometry, the contact lens specialist in consultation with the ophthalmologist will be able to recommend the most suitable contact lens for your keratoconus.

Corneas with keratoconus are very different from each other, it can be said that each keratoconus is different from each other; there are also differences in sensitivity from person to person.

For this reason, the various manufacturers currently make a large number of contact lenses for keratoconus available to the wearer: gas permeable with very diverse bearing geometries and even very high oxygen passage, soft shimmed, and hybrid contact lenses such as Janus, which are gas permeable in the center and soft in the periphery. Hybrid (piggyback) fits are also possible: a soft contact lens on the cornea and a gas permeable one on the soft.

Hybrid solutions are used when there is a need to improve lens comfort and centration. Lenses age and deteriorate with use. They are replaced at different times depending on the type, at most after two years. If there have been changes in keratoconus, one takes advantage of the replacement to change the contact lens parameters to match the new corneal topography. It is rarely necessary to replace a lens after a few months because of a rapid change in the cone.

Corneal transplantation

When keratoconus is in a more advanced stage or contact lenses are not tolerated, the best solution for keratoconus treatment is an anterior lamellar corneal transplant also called DALK (Deep Anterior Lamellar Keratoplasty), which can be performed with different techniques.

In DALK anterior lamellar transplantation, the diseased part of the cornea is removed and the endothelium of the patient’s cornea, which is healthy, is left. The advantage is faster convalescence and fewer complications.

Which are the best keratoconus treatment centers

There are numerous keratoconus treatment centers in Italy. It pays to rely on a treatment center that performs all methods of keratoconus care. The various options complement each other in fact.

Keratoconus Treatment Centers that perform DALK anterior lamellar transplantation are few and selected because this method is technically complex but allows faster recovery and fewer complications. Centers that combine Cross linking with Laser are also selected.

It is worth asking the keratoconus patient association or specialized centers which specialist is closest to your location; early diagnosis and timely treatment are the key to a good result.

Risks

Keratoconus is an eye disease that, if not treated properly, can lead to severe visual impairment.

In the early stages, the lowered vision can be corrected with glasses, contact lenses, Laser surgery or Cross linking but in the advanced stages it is permanent and necessarily requires a corneal transplant.

Corneal transplantation in keratoconus has a very good success rate with current techniques, however if the patient continues to rub the eye or sleep on their stomach or side the keratoconus may recur even after transplantation.

Corneal transplantation in keratoconus has a low risk of rejection however it is an ever-present possibility if appropriate anti-rejection therapies are not performed.

In conclusion, periodic visits and checkups at a specialized center are recommended to avoid all the problems that keratoconus can cause. At our centers in Milan and Catania we routinely perform specialized checkups to prevent and treat keratoconus.

Testimonials

You might also be interested in the following testimonials from Dr Badala's patients: