How to deal with KERATOCONUS?
How to cope up with KERATOCONUS?
How to fix KERATOCONUS?
How to fight KERATOCONUS?
The smartest way to defeat an enemy is to first understand your enemy well. So, to deal with a serious medical condition like keratoconus, you must understand the disease first. So, educate yourself about the condition and consult the Keratoconus Specialists.
To help you in understanding your condition, all the major aspects of keratoconus are discussed here.
What is Keratoconus?
Keratoconus is a serious eye disorder in which the patient’s cornea thins and bulges out into a conical shape which leads to several vision anomalies like distorted or blurred vision, near-sightedness, astigmatism, glares, halos and increased sensitivity towards light. The cornea is the dome shaped part in the front section of the eye, which acts as a window to focus light on to the screen of the eye called retina. The major reason for concern for a keratoconus patient is the progressive nature of the disease.
Keratoconus is the most common type of corneal ectasia (dilation or distension in the cornea) and usually affects a person in the second decade of life and advances up to the fourth decade. It can affect any person irrespective of the gender or ethnicity. According to a survey, keratoconus affects 1 in every 2000 persons in the general population. It usually affects both eyes but individually and to different extents.
Why does keratoconus occur?
The exact cause behind keratoconus is still unknown but doctors consider that the oxidative damage caused due to the free radicals and reduction in the antioxidant levels could be the culprits behind the weakening of the tiny fibers called collagen in the corneal tissue. Free radicals are the highly reactive molecules which can damage the biological molecules like fibers (proteins) by oxidizing them. The damage caused due to these radicals is continuous and progressive until they react with stabilizing molecules called antioxidants. Antioxidants react with these free radicals and prevent the oxidation of the fibers (and other biological molecules) in the non- diseased condition.
When the fibres present in the cornea weaken, they become unable to hold the corneal tissue in its normal intact structure which causes the cornea to bulge out into a cone-like structure. Some of the common factors which contribute to the oxidative damage and hence to the progressive anomaly keratoconus are:
- Genetic predisposition– Keratoconus often occurs in more than one member of the family which support the theory that it is a genetic disorder and can thus pass from parents to their children.
- Enzymatic imbalance – Recent research and reports suggest that the cause of the disorder could be the imbalance in the levels of enzymes present in the cornea which regulates the cumulative process of oxidative damage.
- Ultraviolet rays –Ultraviolet irradiation also appears to contribute to the development of keratoconus due to the enhanced generation of the free radicals in the eyes.
- A history of poorly fitted contact lenses – Poorly fitted lenses causes continuous irritation and discomfort in the patient’s eyes which increases the risk for the development of keratoconus.
- Eye rubbing: Eye rubbing is a common response to even the slightest discomfort in the eyes. Chronic eye rubbing is found to be associated with the development of keratoconus.
How is Keratoconus Diagnosed?
When a person suffers from vision anomalies it is highly recommended that he/she consults an eye specialist like Dr. Irwin Azman so as to get an accurate diagnosis and proper evaluation of the condition.
Keratoconus progresses in two manners: one when the smooth surface becomes wavy and leads to irregular astigmatism and the other when the front corneal surface expands to cause nearsightedness. When a person visits a doctor, his/her eyes will carefully be examined for any corneal irregularities. If the doctor suspects keratoconus, he/she may ask for the diagnostic tests like Topography and/or Optical coherence tomography (OCT) for confirming the diagnosis. Topography is a non-invasive medical imaging technique for mapping the surface curvature of the cornea. OCT is a non-invasive imaging technique which assists a doctor to see cross-sectional images of the patient’s cornea.
What are the available treatment options for keratoconus?
At the initial stages of keratoconus, the patient may benefit from regular contact lenses or eyeglasses but the patient may have to experience prescription change at almost every visit to the eye specialist. As the disease progresses and exacerbates with age, the patient will need more specific treatments and the regular eye glasses or contact lenses do not remain effective enough to provide clear vision.
The choice of treatment option for keratoconus depends on various factors like the current state of patient’s eyes, patient’s medical history, doctor’s expertise and sometimes patient’s preference. So the doctor can suggest from any of the available treatment options, surgical or non-surgical, as described below.
Contact Lenses for Keratoconus (Non-surgical Treatment Options)
- Gas permeable contact lenses–
When regular eyeglasses and contact lenses are not able to control the vision anomalies in a keratoconus patient, gas permeable lenses are the usually preferred solution. These lenses are made up of rigid material which enables them to vault over the corneal surface. Thus, the irregular shape of the cornea is replaced by a smooth and uniform surface of the lens which helps the patient to get a clearer vision.
- Custom soft contact lenses-
Custom soft contact lenses are the lenses which are prescribed to treat patients with mild to moderate keratoconus. As the name suggests these lenses are soft and more comfortable than the rigid gas permeable lenses. They are made with a soft material like silicone hydrogel. Although the cost is a bit higher than gas permeable lenses, they could be worn full time. These lenses are designed specifically on the basis of the detailed measurements of patient’s affected eye.
- Piggybacking –
Gas permeable lenses are an effective option for aiding a keratoconic eye but the process of fitting these lenses over a cone-shaped cornea is quite uncomfortable. Thus, the doctor might suggest a better option known as piggybacking in which two different types of lenses are used together on the same eye. The doctor will first place a soft contact lens over the cornea above which the rigid but effective gas permeable contact lens are placed. Cushioning gas permeable lens with soft lens increases the comfort of the wearer.
- Hybrid contact lenses–
These types of lenses are designed to get the benefits of both the gas permeable lenses and the soft contact lenses. The center of the hybrid lenses is similar to that of the rigid gas permeable lenses whereas the periphery is made up of the soft material as used in the soft contact lenses. The softer peripheral surface increases the comfort level of the patients while putting on the lenses over the cornea while giving the efficiency of gas permeable lenses.
- Scleral and semi-scleral lenses-
Scleral lenses are actually the gas permeable lenses with a diameter which is large enough that the peripheral surface of the lens rests upon the scleral (white layer) layer of the eye while the center of the lens vaults over the irregular corneal surface. Semi- scleral lenses are also similar to the scleral lenses but they comparatively cover a smaller area. These lenses do not exert pressure on the cornea and provide more comfortable fit for the patient’s keratoconic eye. In addition to comfort, these lenses are also more stable than the conventional ones, which usually tend to shift with each blink of the eyes.
- Custom Scleral lenses –
Similar to regular scleral lenses, Custom Scleral lenses, use different techniques to design a custom fit for each individual eye. Examples of custom scleral lenses include EyePrint PRO which uses a molding technique to design the lens and PVR PROSE which utilizes digital technology via an Optical coherence tomography (OCT) to design the lens down to the micron. When a custom scleral lens is fitted properly surgery can be avoided most of the time!
Surgical Treatment Options for Keratoconus are a Last Resort
For patients with keratoconus who can’t tolerate rigid contact lenses for keratoconus or who reach a point where even these lenses could not benefit the patient, the doctor might suggest any surgical option as discussed below. But this should be the last resort!
- Topography-guided conductive keratoplasty –
In topography-guided conductive keratoplasty, the corneal surface of the patient’s keratoconic eye is surgically smoothened to make it uniform. The procedure is guided by an imaging technique known as corneal topography in which a small probe (which uses radio waves) is applied at several points on the peripheral surface of the cornea and the curvature of the cornea is measured. This helps the doctor to make changes in the corneal surface according to the specific need of the patient’s eye.
- Corneal cross-linking (CXL)
Corneal cross linking (CXL) is a surgical procedure done to strengthen the weak keratoconic cornea so as to cease bulging of the corneal surface. The surgery is designed to stop further progression of corneal ectasia (or thinning), which is typically seen in patients with keratoconus and in patients who have had LASIK or RK eye surgery.
Progression slows with age, and in some cases, keratoconus progression halts as early as the age of 20. As a result, patients over the age of 20 will generally have less successful outcomes from CXL. CXL is recommended only for patients whose corneal topography scans show that their keratoconus is progressing or for those who are at particularly high risk of worsening keratoconus (for example, those under the age of 20).
There are two ways of performing the procedure:
- Epithelium off: In epithelium off cross linking, epithelium, which is the outer layer of the cornea, is removed to allow the passage of riboflavin (vitamin B) into the cornea. This is followed by activation of the compound using ultraviolet (UV) radiation.
- Epithelium on: In epithelium on corneal cross linking the epithelium is left undisturbed and compound riboflavin is applied directly to the corneal surface followed by UV treatment.
The CXL procedure strengthens the cross linking of the collagen fibers of the cornea thus it is sometimes also referred as collagen cross linking.
Corneal cross linking (CXL) only marginally improves visual acuity, and in some cases, visual acuity declines. Because of this, patients who undergo CXL often still need corrective lenses.
- Intacs –
Use of intacs, the tiny plastic inserts, is also an effective treatment option to deal with keratoconus. These inserts are surgically placed under the peripheral surface of the cornea thus reshaping it for clearer vision. The procedure can be opted when regular contact lenses or eyeglasses are no longer effective for obtaining clear vision. The use of intacs might delay the requirement of the corneal transplant.
- Corneal transplant–
When all other options are not effective, a corneal transplant is the final treatment option to be considered. The procedure involves the replacement of the keratoconic cornea with a healthy cornea, surgically. The procedure is also known as penetrating keratoplasty.
Although there are a good number of treatment options for the treatment of keratoconus, it is necessary that a person who suspects to suffer from keratoconus or who is experiencing regular prescription changes for eyeglasses should consult a keratoconus expert at the earliest. Early and accurate diagnosis with proper evaluation of the eyes is incumbent for choosing the right treatment option.
Remember! The earlier you find, the earlier you can fight.