What is Keratoconus?
Keratoconus is a progressive condition in which the cornea (the clear front surface of the eye) gradually thins. Due to this thinning, the cornea loses its structural integrity and begins to bulge outward into a cone-like shape, as it is unable to withstand the natural fluid pressure inside the eye
This structural change results in what is known as irregular astigmatism, which severely distorts light as it enters the eye. Because of the irregular shape, conventional glasses are typically not adequate to correct vision and achieve a satisfactory standard of clarity. Risk factors for keratoconus include genetics (family history), eye rubbing and atopia (including conditions such as asthma and eczema).
Diagnosis
(Corneal Topography)
Keratoconus is often identified during the course of a routine eye examination. The primary method for confirming and monitoring the progression of keratoconus at Acuity Eyecare is Corneal Topography. This non-invasive imaging technique provides a precise, three-dimensional map of the cornea. This mapping is invaluable, as it assists our optometrists in determining the exact extent of the bulging and monitoring for any subtle progression over time.
Treatment & Management
Collagen Cross-Linking: Treatment to prevent progression of keratoconus involves collagen cross-linking. This is a medical procedure designed to strengthen the corneal collagen fibres to prevent further thinning and halt the progression of the condition. While this does not "cure" the existing shape, it is vital for stabilising the eye.
Visual Correction: Once the cornea has developed an irregular shape, glasses are often insufficient for clear vision. Speciality contact lenses are required to "mask" the imperfections caused by the corneal thinning. Rigid Gas Permeable (RGP) lenses, or hard contact lenses, provide a perfectly smooth front surface that rests over the eye. The tears or solution filling the space between the lens and the cornea create a "liquid lens" that effectively cancels out the irregular corneal shape, allowing light to focus correctly and providing life-changing clarity.
Speciality Keratoconus Lenses
Our optometrists specialise in fitting advanced lenses customised to the unique topography of your eye. These are critical for achieving clear vision where glasses have failed.
The design and diameter of these lenses vary depending on the severity of the corneal bulge:
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Small RGP Lenses: Traditional hard lenses, typically 8mm or smaller in diameter.
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Miniscleral Lenses: Larger designs (approximately 12mm) that provide increased stability and comfort.
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Scleral Lenses: Measuring 16mm and larger, these lenses "vault" entirely over the sensitive cornea and rest on the white part of the eye (the sclera).
By holding a constant reservoir of fluid over the cornea, these advanced lens designs provide life-changing clarity and comfort for our patients.