What is Keratoconus? Understanding Early Signs, Causes, Epidemiology, and Modern Treatments

Keratoconus is a progressive eye disorder in which the cornea, normally round and dome-shaped, thins and begins to bulge into a cone-like shape. This causes distorted vision and increased sensitivity to light.

Usually starting in adolescence or early adulthood, keratoconus can significantly impair vision if left untreated.

Dr. Mark Deist, an ophthalmologist in Sandton, Johannesburg, uses the most modern and scientifically validated treatment options to manage this condition, aiming to halt progression and improve visual function.

Early Signs of Keratoconus

The initial symptoms often include blurred and distorted vision that cannot be fully corrected with regular glasses due to irregular astigmatism. Early signs are frequent changes in eyeglass prescriptions, glare, halos around lights especially at night, and sensitivity to bright lighting.

Patients may also experience ghost images or double vision in one eye. Early ophthalmic evaluations reveal asymmetric corneal curvature irregularities using topography and keratometry to detect these subtle changes.

Causes and Risk Factors

Keratoconus is believed to arise from a combination of genetic predisposition and environmental factors. A family history of keratoconus increases the likelihood, and environmental factors such as chronic eye rubbing, allergies, and exposure to ultraviolet rays contribute to disease onset and progression.

Certain systemic conditions like Down syndrome and connective tissue diseases can increase the risk.

The underlying mechanism involves weakening of the corneal collagen structure leading to progressive thinning and bulging.

Epidemiology of Keratoconus in South Africa

The prevalence of keratoconus in South Africa is notably high compared to global averages, with estimates ranging from about 10% to over 30% in certain populations, particularly among Black African and female patients.

Hospital-based studies in Johannesburg indicate a substantial number of patients presenting with moderate to severe disease stages, reflecting challenges in early detection and intervention. These figures suggest a significant public health concern requiring increased awareness and access to modern management strategies within South Africa.

Initial Treatment Options

Early-stage keratoconus management begins with conservative, non-surgical options. Spectacles are often prescribed initially to correct mild refractive errors and astigmatism. As the disease progresses and spectacles become insufficient due to irregular corneal shape, specialized hard (rigid gas permeable) contact lenses are introduced to provide better vision correction by creating a smooth refractive surface over the irregular cornea. These lenses are a mainstay for many patients and can significantly improve visual acuity and comfort.

Modern Surgical and Advanced Treatments When contact lenses are no longer adequate or the disease progresses, Dr. Deist offers advanced surgical treatments tailored to the patient's condition:

• Corneal Collagen Cross-Linking (CXL): This technique uses riboflavin eye drops and ultraviolet light to strengthen corneal collagen fibers, halting progression. Success rates typically exceed 90% in stabilizing the disease and preventing further corneal thinning.
  

• Photorefractive Keratectomy (PRK): Often combined with CXL, PRK reshapes the corneal surface to reduce irregular astigmatism and improve vision. Studies show combination treatments have superior outcomes compared to either treatment alone, with significant improvements in visual acuity and corneal stability.
  

• PACE Procedure (Photorefractive Assisted Collagen Cross-linking): This combines corneal reshaping and cross-linking in one session, providing expedited visual recovery and enhanced corneal strength.
  

Advanced treatments provide substantial improvement in vision and quality of life, especially when applied early. In more severe or scarred cases, corneal transplantation may be necessary but is increasingly rare due to advances in early intervention.

Success Rates

• Spectacles: Effective initially but limited as keratoconus progresses.

• Hard Contact Lenses: High success in improving vision for moderate stages, but fitting can be challenging.

• CXL: Over 90% effective in halting progression.

• PRK combined with CXL: Superior visual outcomes and stability, with significant improvements in acuity and refractive error.

• PACE: Emerging data suggests excellent combination benefits, with reduced recovery times and improved corneal biomechanics.
  

Dr. Mark Deist’s expertise ensures patients in Johannesburg receive personalized care combining established and cutting-edge therapies to best address individual keratoconus challenges.