Keratoconus - Causes, symptoms and treatment. MF.

Keratoconus is a disease of the cornea not of inflammatory origin, characterized by its thinning, protrusion and turbidity. It is mainly found in middle-aged and young people of 20-40 years, almost always a two-way process.

Schematic diagram of keratoconus

Reasons for keratoconus

Factors predisposing to the appearance of pathology:

- genetic( for example, in certain hereditary diseases such as Ehlers-Danlos's disease, Leber's amaurosis, blue sclera syndrome, etc.),
- exposure to ultraviolet by eye(more common in the inhabitants of the mountain and southern regions),
- corneal diseases,
- use of incorrectly selected contact lenses

In keratoconus, the cornea in the central zone is thinnedAccording to this last one it is associated with increased apoptosis, i.e. programmed cell death), the front pressure chamber and the moisture it bulges turbid with time.

Symptoms of keratoconus

Keratoconus can be acute and chronic. Sudden keratoconus is rare and occurs in later stages due to the fact that the Descemet's membrane is torn and the moisture of the anterior chamber infiltrates the stroma. There are severe pains, a sharp loss of vision due to corneal edema. Its perforation is possible.

Acute keratoconus

Stages of keratoconus:

I-II - minor morphological changes in the cornea, nerve endings are well visualized;
III - corneal opacities in the region of the apex of the cone, crack descemet cladding;
IV - opacification and thinning of most of the cornea;
V - almost complete corneal opacity

Symptoms that can be suspected of developing keratoconus: decreased visual acuity, frequent glasses change( as the cornea continues to bulge and myopia and astigmatism increase), distortion of objects( due to the development of astigmatism), canthere is pain, photophobia and lacrimation.

Diagnosis of keratoconus

The correct diagnosis can be made only by an ophthalmologist after carrying out certain research methods:
- external examination - protrusion of the cornea in the form of a cone with a top directed downwards;
- definition of visual acuity with correction and without;
- when refractometry is detected, incorrect astigmatism and myopia due to protrusion of the cornea;
- biomicroscopy - a thin cornea, may be its opacities, descemet membrane cracks( Vogt lines), deep anterior chamber;in the late stages appears the deposition of hemosiderin at the base of the keratoconus( Fleischer's ring);
- for skiascopy is characterized by a specific movement of the shadows towards each other;
- ophthalmoscopy in the transparent environment of the eye;
- ultrasound;
- keratopachymetry - determination of the thickness of the cornea;
- optical coherence tomography;
- computer keratotopography - the configuration and refraction of the cornea in its different parts;

Keratotopography

- confocal and endothelial microscopy allows diagnosis in the first and second stages of the disease

It is very difficult to diagnose at the initial stage of the disease.

Treatment of keratoconus

Treatment should be started immediately after the detection of keratoconus. There are conservative and surgical methods.

At the beginning of the disease, soft or hard contact lenses are selected. Conservative therapy also involves the use of drugs that improve the metabolic processes in the cornea. These include Taufon, Quinaks, Oftan-katakhrom, retinol, sea buckthorn oil. Bury 3 times a day all the time. It is also possible to use subconjunctival and parabulbar injections of emoxipin, ATP.Inside must take vitamin preparations. A good effect of physiotherapy, for example, phonophoresis with tocopherol, magnetotherapy.

Emergency care is needed in case of acute keratoconus to keratoplasty. Bury the mydriatic( Mezaton, Midratsil, Tropicamide), use a 5% ointment of sodium chloride and apply a pressure bandage to prevent corneal perforation. Also locally applied antibacterial drops( Tobrex, Floxal), anti-inflammatory non-hormonal( Indocollir, Diclof, Naklof) and hormonal( rp dexamethasone, for example, Maxidex), and hypotensive drugs - Timolol( Arutimol, Kusimolol) 1-2 times a day.

One of the modern methods of therapeutic treatment of keratoconus is cross-linking. First anesthetize and remove the upper layer of the epithelium, then saturate the cornea with riboflavin multiple instillations. Then they are exposed to ultraviolet rays using a Sailer lamp. A number of biochemical reactions take place in the cornea, as a result of which collagen fibers are strengthened and flattened. After cross-linking, a therapeutic contact lens is worn for several days. The entire procedure takes about an hour, the curative effect lasts up to 10 years.

With intolerance of contact lenses or ineffective correction due to corneal opacity, surgical treatment is resorted to - through keratoplasty( corneal transplantation).With an absolutely transparent transplant, recovery occurs in more than 90% of cases. Rejection is almost impossible, becausein the cornea there are no vessels. The only drawback is that after the operation, you have to wear contact lenses for quick healing.

Intrastromal segments of

rings The method of implantation of intra-stromal corneal rings or their fragments is applied. A small incision is made at the periphery of the cornea and several rings of a certain radius and thickness are placed in the stroma. They stretch the cornea, and thus the degree of keratoconus decreases.

Endoscopic keratoplasty

In the initial stages with sufficient thickness of the cornea, it is possible to perform such operations as photorefractive and phototherapeutic keratectomy. These methods allow not only to restore visual acuity and correct astigmatism, but also strengthen the front layers of the cornea, which slows the progression of keratoconus.

Complications of keratoconus

Treatment should begin as soon as possible after diagnosis to prevent the progression of the disease and the development of complications such as corneal perforation, its turbidity, the emergence of acute keratoconus.

Doctor ophthalmologist Letyuk T.Z.