Keratoconus –
General Information by the Leading Oak Lawn Eye Doctors

Keratoconus is a condition in which the cornea of the eye is “cone shaped”. A normal cornea has a smooth, regular curvature which resembles a section of a sphere or, in cases of astigmatism, somewhat the shape of a football. The keratoconic cornea with its cone-like bulge has an irregular shape, and in its moderate to advanced states causes blurred, distorted vision which cannot be properly corrected by regular glasses. As the shape of the cornea bulges out it becomes thinner and no longer can support itself. No longer having the support the cornea will kink causing the irregular astigmatism leading to distortion.Keratoconus is one of a group of corneal degenerations that is characterized by corneal thinning. These conditions are termed “Ectasias” of the cornea.

Keratoconus is a non-inflammatory condition, and is usually caused by a progressive thinning of the central corneal tissues. Occasionally it may have other causes such as improperly fitting rigid contact lens or trauma. Usually the trauma is caused by intense rubbing and itching. The etiology of the corneal thinning is not known, although when looking at the corneal tissue microscopically the support fibers are missing.In some cases it appears to be hereditary starting around puberty. Keratoconus usually occurs in both eyes, though one eye may be more affected than the other.

Keratoconus is a relatively rare condition, and is said to afflict less than 1 person out of 2 thousand. However, because the severity of Keratoconus varies greatly, milder cases are not always diagnosed.

Keratoconus condition

Keratoconus is suspected when frequent changes in glass prescription are characterized by increasing near sightedness and marked increase in astigmatism. The condition may be easily diagnosed by using instruments such as the topographer which measures the central and peripheral corneal curvature. As the condition progress the curvature readings become steeper and begin to appear irregular. The entire shape and thickness of the cornea can be measured by an OCT instrument which measures the size and the configuration of the cone. At some point in the disease process your doctor will note visible thinning of the cornea under the biomicroscope along with folds in the cornea (called “striae”). Other clinical signs include the deposition of iron in the cornea (“Fleisher’s Rings”), corneal scars, large increases in astigmatism, and reduced correctable vision with glasses.

Normal Cornea
Keratoconic Cornea

Because the corneal surface of a keratoconic eye is distorted and irregular, the best visual acuity can only be achieved by replacing the primary refractive surface. This can usually be achieved by covering the corneal surface with a contact lens or replacing its central section with a corneal transplant supplied by a donor. Refractive surgery techniques such as LASIK are contra-indicated in cases of Keratoconus, because removing more tissue for the already thin cornea may cause it to collapse.

Corneal Topography

When contact lenses are used, special design lenses are the lens of choice rather than soft disposable lenses which are thin and flexible and follow the contour of the eye, and therefore are usually not effective when used as a correction for Keratoconus. Very occasionally, soft disposable lenses are used in conjunction with hard lenses which are “piggy backed” on top of the soft lens surface.

Treatment for Keratoconus

The early stages of keratoconus, conventional eyeglasses can correct the mild myopia (nearsightedness), and astigmatism that develops. At these stages vision is often correctable to 20/20. As the disease progresses a loss of best corrected glasses vision occurs. It is then that special keratoconus contact lenses are required to achieve clear vision. The contact lenses function to “mask” the irregularity of the corneal surface, thus increasing the quality of vision in comparison to the vision through glasses. For many years the only method to correct vision well in keratoconus was with the use of hard contact lenses and then eventually rigid gas permeable contact lenses.The preferred materials for use in fabricating lenses for keratoconus isrigid gas permeable plastic which permits oxygen to pass through the lens and therefore help maintain the normal metabolism of the corneal surface. These lenses must be custom made to provide the optimum fit over the irregular corneal surface of a keratoconic cornea. In cases where the lens is not fit properly the surface of the lens will put pressure on the tip of the caone causing the disease process of keratoconus to progress leading to scar tissue formation or perforations. Unfortunately, the recent advances in the plastic used for lenses are not always combined with the best in custom fitting, and many contact lens wearers with Keratoconus suffer unnecessary discomfort and sometimes even the inability to wear the lenses that they depend on for normal vision 24 hours a day.

Patients with keratoconus today have many options for treatment including rigid gas permeable lenses, hybrid SynergEyes lenses, special design soft lenses for keratoconus and scleral lenses to provide excellent visual results in many cases.

Rigid Gas Permeable Lenses

KBA bi-aspheric, S-Cone, B-Cone, C-Cone (Essilor Labs)
IKone bi-aspheric, V-Cone, K Vault (Valley Contax)
McGuire designs, AO Cone, Rose K Designs (Alden)
Soper designs (Soper International)
C-cone, E-cone, X-cone (ABB Optical Group)
Horizon Cone (Accu Lens Inc)
Naturalens VIP Cone (Advanced Vision Group)
CentraCone, Rose K Designs (Blanchard)
Conforma-K (Conforma Labs)
Danker K (Danker Labs)
Dyna Cone, Quad SymDyna Cone (Lens Dynamics)
ComfortKone (Metro Optics)
K-Max (Visionary Optics)
Apex (X-Cel Contacts)
“Piggy-back” lens systems (combinations of soft disposable lenses and any gas permeable lens)lenses fit over the soft lens for improved comfort and fitting)

Special Design Soft Lenses for Keratoconus

Kerasoft IC (Bausch and Lomb)
Hydrokone (Visionary Optics)
NovaKone (Alden)
Concise K (ABB Optical Group)
Biopermkeratoconus (Orion Vision)
Soft K and NaturaSoft (Advanced Vision Technologies)
Continental Cone (Continental S L)
Keratoconus Lens (Gelflex USA)
TricurveKeratoconus and Flexlens (Xcel Contacts)
Solus (SLIC) and UCL-55 keratoconus (United Contact Lens)

Hybrid SynergEyes (Gas Permeable Center Soft Skirt)

SynergEyes KC
Clear Kone
Ultra health

SynergEyes has developed a unique hybrid lens design for vision and comfort that have a highly oxygen rigid gas permeable central area and a soft periphery. Failures with rigid lenses generally are caused by long wearing times and the inability of the tears to lubercate the cornea causing discomfort and chaffing. The goal is to provide the same crisp optics of a rigid gas permeable lens and the comfort and positioning stability similar to a soft contact lens. The most recent development in hybrid designs is the Ultra Health lens. The Ultra Health has unique geometry of both the rigid center and soft periphery. The result is a lens that vaults the central cornea and aligns with the soft periphery from the peripheral cornea out to the sclera. The lens has excellent centering, movement, and comfort characteristics. Davis EyeCare has been able to fit patients with keratoconus who have failed with many other lens designs. Light blue rigid center and soft skirt of a Synergeyes lens.

Scleral Lenses

Jupiter Scleral, Europa Scleral (Visionary Optics)
Macrolens (Dakota Vision)
Mini Scleral Design, Onefit C, Onefit P & A (Blanchard)
Intra-Limbal design, Dyna SEM-Scleral (Lens Dynamics)
Comfort SL (AccuLensInc)
AVT Scleral, ALC Scleral (Advanced Vision Technologies)
SO2Clear Corneal Scleral Design, Rose K XL Semi Scleral ( Art Optical)
SEM Scleral, EB 15.0, Jupiter Scleral (Essilor)
Digiform Scleral (TruForm Optics)
Titan, Atlantis Scleral (C-Cel Contacts)

Scleral contact lenses are large diameter gas permeable lenses that vault the cornea and align to the peripheral sclera of the eye. Most of the discomfort from a rigid lens is caused by the lids. Scleral lenses are fit where the lens is tucked underneath the upper and lower lid resembling a soft lens.

Also, there are few nerve endings on the cornea, therefore scleral discomfort is rarely experienced. The vaulting of the cornea leaves a healthy tear layer between the back of the lens and the front of the cornea. This prevents any lens induced irritation or material getting underneath the lens causing discomfort on the corneal surface and promotes excellent “wetting” of the front of the eye. We utilize numerous sclera lens designs and laboratories which are selected based on the specific requirements of the individual patient.

Corneal Transplantation

Advanced Keratoconus may result in corneal scars and opacities which may lead to the need for a corneal transplant. It is important that the transplant be performed before the area surrounding the central cornea becomes too thin. All told, approximately 10,000 corneal transplants are performed each year in the United States for various conditions, including Keratoconus. Corneal transplant surgery is an art as well as a science, and it is important that those seeking such surgery find an experienced and successful surgeon. Davis EyeCare co- manages corneal transplant surgery with some of the leading surgeons in the United States. Today eye banks allow for surgeries to be scheduled without a waiting list. The rejection rate of this tissue transplant is extremely low due to the cornea being a vascular. When performed properly, the surgery is relatively non-traumatic, and is over 90% successful. After the surgery many Keratoconus patients experience normal vision though most will require the additional use of contact lenses or glasses.


Intacs are small semicircular shape implants that can be surgically placed between the layers of the corneal tissue to attempt to change the shape of the cornea to a more regular configuration. Initially developed for the correction of myopia (nearsightedness), doctors began to utilize Intacs for certain cases of keratoconus to provide a relatively more regular front surface. By changing the shape of the cornea from its distorted configuration improves vision in many cases. Many patients corneas shape changes to a more normal configuration allowing a more stable contact lens fitting. Davis EyeCare co-manages with the leading corneal surgeons in the country who perfected this technique. Dependent on your individual case we will discuss with you this options and our expectations for success.

The corneal in Keratoconus does not have the supporting tissue to support the corneal structure. Collagen Cross Linking with Riboflavin (C3-R) adds the support by increasing the stiffness and rigidity of the cornea and stabilizescorneal structure. This procedure is extremely useful for patients with mild keratoconus to stop the progressive of corneal thinning (ectasia). It is not known whether the stabilizing effect of C3-R® on keratoconus is permanent, but the C3-R® treatment could potentially be repeated if it was necessary.

The bulk of the cornea is made from collagen fibers which are arranged in bundles. The strength and rigidity of the cornea is partly determined by how strongly the fibers are linked together. Over the course of a lifetime the cornea becomes progressively stiffer due to natural cross-linking between the fibers. Patients with keratoconus has been shown to be absent of these natural cross-linking fibers.

Patients with keratoconus

Riboflavin (vitamin B2) is a naturally occurring compound which strongly absorbs UV light. By applying riboflavin to the cornea at the same time as exposing it to a UV light source, the riboflavin not only enhances the cross-linking effect of the UV light, but also absorbs the light to an extent that the inner layers of the cornea and intra-ocular structures are protected from the potentially damaging effects of the light rays.

Davis EyeCare has worked with the leading surgeons who have developed this technique. The ongoing investigations are evaluating the safety and efficacy of C3-R for keratoconus. Davis EyeCare will discuss with you the advantages of this new treatment.

Keratoconus Symptoms and Medical Necessity for Contact Lenses

Keratoconus (ectatic corneal dystrophy) is a progressive, debilitating bilateral eye disease in which degenerative thinning of the cornea results in complex irregular bulging of the normally round, spherical cornea (the clear covering in front of the eye). Keratoconus results in grossly distorted vision, causing ghosting and glare similar to looking through a windshield while driving in a rainstorm without using windshield wipers. Keratoconus is characterized by thinning and protrusion of the central cornea, resulting in visual distortion, photophobia, halos around lights, decreased vision, and monocular diplopia (double-vision).

car lights

Those with keratoconus suffer from decreased vision which cannot be corrected with spectacles or conventional contact lenses. However, most keratoconic patients can achieve functional vision with specially designed therapeutic contact lenses.

Keratoconus is one of the few conditions where contact lenses are a medical necessity (other conditions include unilateral aphakia, post corneal transplant, and very high myopia). It is well documented that rigid gas permeable contact lenses or a combination of rigid gas permeable lens riding on a soft lens configuration are the treatment of choice for keratoconus.

These uniquely designed keratoconic lenses improve vision by providing a clear optical lens that masks the distorted areas of the cornea creating a smooth, regular optical surface over the patient’s very irregular, cone-shaped cornea. These lenses can mask the distorted vision caused by keratoconus and can provide the required visual acuity necessary to perform daily routines. Without these corrective lenses these patients are visually handicapped. They would not be able to hold a job and therefore support themselves and their families. They would not be able to perform even the simplest tasks of daily life: read, drive a car, attend school or even recognize a face across the room.

Spectacles cannot achieve these results. The lenses in a pair of glasses are too far away from the optical surface of the cornea to create the smooth refractive surface necessary to translate the image clearly to the back of the eye and therefore to the brain.

parking sign

These therapeutic contact lenses are not cosmetic. They are specially designed devices that treat a medical problem. Just as a leg brace helps a lame patient to walk, these therapeutic contact lenses provide a treatment plan to improve the quality of life.

The only other therapeutic option for rehabilitating vision in the keratoconus patient is penetrating keratoplasty (corneal transplant surgery). Because of the inherent risks with surgery and high cost, this option is only reserved for patients who cannot receive treatment from contact lenses.

Based on the above information about keratoconus, we trust that you will deem these corrective lenses medically necessary and worthy of insurance coverage for the diagnosis of keratoconus.

For more information consult Dr. Robert Davis of Davis Eyecare.

Quality of Life for the Patient with Keratoconus

Keratoconus patients are desperate to find a solution to their visual problems that most people take for granted. People don’t think of vision as being problematic. Keratoconus patients must contend with contact lenses or contemplate a surgical procedure to improve the quality of their life. Eyeglasses usually do not provide adequate sight to perform most daily tasks. So the keratoconus patient must rely on a visual device on the already fragile cornea, due to the thinning of the cornea to gain optimal acuity. It is an understatement to state that the lifestyle is altered due to this corneal abnormality. Navigation at night is difficult and the questionable constant conscious state of comfort and vision plagues the keratoconus mindset.

The Cost of Keratoconus

Cost for therapeutic devices for the keratoconus patient can limit the solutions. Major medical insurance companies should cover this medical anomaly. The attitude of the insurance companies is to force the patient to go through barriers before payment is guaranteed. It is my experience that most keratoconus patients are so hopeful of the expected outcome that they pay for the care and take on the insurance companies by themselves. This usually results in the keratoconus patient giving up on the insurance companies because of the time it takes to convince the insurance company that the procedure is not a cosmetic procedure but a medical necessity. The goal of this article is to provide the keratoconus patient with the ammunition to gain payment for this medical procedure.

Keratoconus gradually causes the central area of the cornea to weaken, thin or bulge. It eventually distorts from its more spherical shape to a cone shape. This distortion may cause significant changes in vision which may begin in the late teen years and may not stop until age 40. While keratoconus can be an inherited bilateral (two eye) condition, many patients have no clear inheritance pattern. It has been estimated to occur in 1 out of every 2,000 persons.

The earliest changes of keratoconus may require frequent changes of glasses. As the corneal distortion worsens, contact lenses may be required to obtain adequate vision. In this case, contact lenses mask the warp or cone-like changes of the underlying cornea. Generally, most keratoconus patients can be safely managed with contact lenses yielding good vision and comfort.

In more advanced cases of keratoconus, vision in an eye can be suddenly, yet usually temporarily, lost through an event called “hydrops.” During this process, the stretching cone-area of the cornea cracks, swells and in some cases scars.

When contact lenses can no longer correct vision adequately, or when highly specialized contact lenses can no longer be made to remain comfortably on the eye surface, surgical replacement of the distorted corneal area may be considered with no guarantee of success. Surgical treatment is found to be necessary in only about 10% of the cases. This surgery is performed using donor cornea tissue to return the eye surface to a more normal shape. Patients who handle their keratoconus problems successfully develop their own coping mechanisms. Sunglasses are advised to reduce glare symptoms. The condition may be easily diagnosed by using instruments such as the corneal topographer which measures the central corneal curvature. As the condition progresses the curvature readings become steeper and begin to appear irregular. Computerization of this corneal mapping process adds sophisticated algorithms to the intricate process of understanding the complex surface of the front of the eye. Corneal topography is a modern invaluable tool to assist in the diagnosis and treatment of keratoconus.

Cosmetic Versus Medical Procedure

Approximately 85% of all contact lenses are worn for either convenience or appearance and 15% are worn for the visual advantages possible with certain conditions such as severe nearsightedness, severe astigmatism, and following cataract removal. Although the contact lenses are of great benefit for those with severe visual conditions, eyeglasses can still be worn as an alternative, although vision might not be as good. With keratoconus, however, eyeglasses cannot provide adequate vision because of the conically deformed cornea. The only non-surgical method to provide adequate vision for the keratoconus patient is replacing the deformed cornea with a regular front surface for the eye -this is accomplished by the fitting of a special rigid contact lens. If contact lenses cannot be worn, then the only alternative is corneal transplant surgery. This is the key in getting the insurance companies to pay attention to the nature of the therapeutic remediation. The choice you are giving the insurance company is either the less expensive contact lens or the more expensive corneal transplant. Both are medical procedures for the anomaly of keratoconus.

Insurance Coverage for Keratoconus

Insurance coding is another important procedure that must be included in the submission for insurance coverage. There are two parts included for insurance submission. The first is the diagnostic code and the second is the examination and treatment. The (International Classification of Disease 9th Revision Clinical Modification) ICD-9-CM code is 371.61, 371.70 defined as bilateral bulging protrusion of anterior cornea, often due to non-inflammatory thinning. The (Current Procedure Terminology) CPT code is 92070 defined as fitting of contact lens for treatment of disease, including supply of lenses. Another approach is to submit for the evaluation including corneal topography (92499), the contact lens fitting and instruction (92310) and the lens material separately (V2511). Symptoms associated with keratoconus can be described to enhance the submission such as blurred vision (368.8), irregular astigmatism (367.22), monocular diplopia (368.2), Photopobia (368.13), Cornea striae (371.32), Corneal scarring (371.00) and/or Corneal Fleischers Ring (371.11). Most insurance carriers verify that the visual acuity through contact lenses will be an improvement over glasses for full coverage under the medical umbrella.


Patients who have major medical coverage pay monthly premiums in the event that they are afflicted with a health anomaly to minimize their financial responsibility. Premiums increase yearly as the insurance companies’ gamble that their incidence will offset their liabilities. Insurance statistics provide the risk analysis that quantifies the monetary exposure for the diagnosis and treatment of keratoconus. It is necessary that we educate the underwriters that keratoconus is no less severe than any other medical disorder. A contact lens is essential to provide a smooth optical surface on the cornea for optimal vision. The topographical map is an objective test defining the corneal disorder. The contact lens is not cosmetic but is a prosthetic device, which allows the patient to continue to perform daily activities.

For more information please consult Dr. Robert Davis at our Oak Lawn office.