It is an ocular pathology that consists in the deformation and progressive change of the cornea, which is the transparent tissue located in front of the iris and pupil.
In keratoconus, corneal thinning occurs due to normal eye pressure that pushes the weakened surface and deforms it. The normal round shape of the cornea becomes conical, whereby it is also known as “Conical Cornea”. This deformity causes significant visual changes in the patient, leading to blurred and distorted vision. The extent of this disease is from mild to severe. The progress is variable, generally slow and can stop at any time. Only in extreme cases it may cause blindness. Keratoconus is a rare eye condition. It is estimated to affect 1 in 4,000 people but it occurs more often in patients with Down syndrome, allergies or amaurosis. Keratoconus may be suspected when the patient requires too frequent changes in graduation of his eyeglasses, which generally leads to astigmatism and/or myopia. A Pentacam examination is recommended for these patients, which allows using several parameters and/or values to consider through observation, the need to place Intrastromal rings, cross linking, or corneal transplantation. Below is a description of each one of these treatments:
Is a new treatment option that comes up with the use of collagen cross-links for keratoconus and the placement of Intrastromal rings or both, in order to decrease visual problems. The cross linking treatment involves scraping the patient’s cornea to apply Riboflavin (vitamin B2), a substance that sensitizes the collagen. Then, the creation of these new bridges or bonds between the long chains of collagen is stimulated by radiation of special light within the ultraviolet range of a given wavelength, which applies a specific energy at a given distance for a preset time (30 minutes).
Its purpose is to correct keratoconus, totally or partially, improving visual acuity in most cases. It is a corneoplastic surgery because its main purpose is to correct the deformity of the cornea. Cylindrical segments of plastic are placed in the cornea in the shape of a full ring or half-ring, as appropriate. They are implanted under anesthesia with drops and the patient can return to his normal activities in four days. Although rings have high tolerance, they can be removed without difficulty if necessary. Keraring rings assume that the greater the thickness, the greater the correction; also, the smaller diameter of the implanted segments, the greater the dioptric correction. They modify the tensional forces on the tissues and maintain corneal sphericity. In turn, they change the forces between the distal ends of the segments lifting the tissue comprised between them. The surgery is ambulatory, that is, that the patient leaves the clinic the same day of the operation, after a 30-minute observation period following anesthesia with pseudoanalgesia administered by an anesthesiologist to reduce patient’s anxiety. Topical anesthesia is also administered by a few eye drops in both eyes at once, because the procedure does not require the use of any dressing. It is important that the patient is accompanied by a person of trust. Once the anesthetic drops have been applied, a 1-mm incision will be made in the peripheral cornea to form two semicircular tunnels where the rings are inserted.