1 in 2,000 of humanity gets this condition, varying from minor impact on life to utterly devastating for visual quality. The clear dome in front of the iris is called the cornea; it is composed of long strands of collagen crossing from border to border in parallel layers, somewhat akin to spaghetti strands before cooking. These strands are cross-linked to each other like the wire straps between double-brick walls. Should these cross-linkages fail the curve of the cornea slowly prolapses creating irregular focus that eventually cannot be accurately managed by spectacle or soft contact lens. The clarity of the world just gets messier to the point of ‘very very poor’.
What causes conical cornea?
Conical cornea is only partly genetic – it more frequently affects those with multiple allergies and is especially prevalent in asthmatics that suffer with eczema.
1. EVERYONE should stop eye-rubbing, use of medications at hay-fever season, antihistamine tablets, eyedrops, Rx drugs of whatever potency it takes to reduce eye-fire itchiness.
2. Minor cases – spectacles or soft contact lenses for vision as necessary, keep photographing eye curves with topographer for comparison studies.
3. Consider collagen cross-linking by specialist corneal ophthalmologist to bind layers more tightly, usually STOPPING PROGRESSION immediately. This procedure usually does pull the apex back a little, unfortunately not yet in a predictable or controllable degree.
4. If / when spectacle or soft contact lenses do not give acceptable clarity of vision for holding driving license etc, we have customised rigid contact lenses of many designs to consider. Solid lens ‘vaults’ the irregular eye curve, filled with fluid ( tears/ saline) and the irregular maths are cancelled out, the front surface of the contact lens becomes the dominant refractive effect, we get CRISP VISION again.
5. Designs for RGP lenses include Gelflex KORB, Aspheric, Capricornia KBA, Epicon, ICD-16, U/H Hybrid, and occasionally I employ piggy-back of a disposable lens + RGP on top ! Every situation is an Individual EyeCare Solution. All these lens types require a specific cleaning and care regime and replacement on schedule.
6. WORSE CASE SCENARIO – becoming a lot less common, but cornea graft surgery is sometimes necessary. I will never hesitate to refer people to the corneal specialist surgeon if I suspect this to be a consideration. This is a HEAVY DECISION when undertaken.