Myopia - Causes, Symptoms, Diagnosis and Treatment
Myopia (Myopia) - refractive eye anomaly strength (refraction), characterized by the image of subjects focusing not on the retina, but in front of her. When myopia bad people distinguish distant objects, but can clearly see close; celebrated visual fatigue, headache, night blindness, progressive deterioration of visual acuity. Diagnosis of myopia include visometry, skiascopy, refractometers, ophthalmoscopy, biomicroscopy, ultrasound of the eye. When myopia required to comply with hygiene, wearing glasses with spread lenses, contact lenses; surgical correction of myopia surgical methods (lensektomiya, implantation of phakic lenses, radial keratotomy, keratoplasty, kollagenoplastika) or with laser surgery (LASIK, SUPER LASIK, LASEK, PRK, and others.).
Myopia
ophthalmology myopia has another name - myopia.
myopia in children develops in 50% of cases; parents with normal vision - only 8% of children.
A common cause of promoting the development of myopia, acts of non-compliance with hygiene requirements: visual excessive load duration at close range, low light workplace, long-term work at the computer or watching TV, reading in public transport, wrong planting in reading and writing.
Often precedes the development of true myopia false myopia caused by congestion of the ciliary (accommodative) and muscle spasm of accommodation. Myopia may be accompanied by other oftalmopatologiya - astigmatism, strabismus, amblyopia, keratoconus, keratoglobus.
The adverse impact on visual function have borne infections, hormonal fluctuations, intoxication, birth injuries, brain injury, worsening the microcirculation in the eye membranes. Contributes to the progression of myopia deficiency of trace elements such as Mn, Zn, Cr, Cu, etc., Has identified an incorrect correction of myopia.
Diabetes, corticosteroids, sulfonamides, in the early stages of cataract development.
According refractometry and strength necessary correction in diopters myopia distinguish between mild, moderate, and high:
The degree of high myopia can reach significant values (-15 and -30 diopters).
headaches, aching in the eyes, pain in the eye sockets. Against the background of myopia can develop Heterophoria, monocular vision and divergent strabismus friendly.
When progressive myopia patients are forced to frequently change the glasses and lenses to stronger, because after a while they no longer correspond to the degree of myopia and correct vision. Progression of myopia is due to the stretching of the eyeball, and often occurs in adolescence. Lengthening the anterior-posterior axis of the eye with myopia accompanied by an expansion of the optic fissure, which leads to a small bug-eyed. The sclera in tension and thinning takes on a bluish tinge because of the translucent vessel. Floater can be shown "flying flies" feeling "of skeins of wool", "yarn" in front of his eyes.
When you stretch marked elongation of the eyeball ocular vessels, violation of retinal blood circulation, decrease in visual acuity. Friability blood vessels can lead to bleeding in the retina and vitreous. The most severe complication of nearsightedness can be a retinal detachment and its accompanying blindness.
ophthalmic tests, inspection structures of the eye, the refraction studies of ultrasound eye.
Visometry (visual acuity test) is carried out on a table with a set of trial spectacle lenses and is subjective. Therefore, this type of research should be complemented with myopia objective diagnosis: skiascopy, refractometers, which are conducted after cycloplegic and allow us to determine the true value of refraction of the eye.
Carrying ophthalmoscopy and biomicroscopy with Goldmann lens, eyes with myopia is necessary to identify changes in the retina (hemorrhage, degeneration, myopic cone spots Fuchs), protrusion of the sclera (staphylomas), clouding of the lens, and so forth.
To measure the anterior-posterior axis of the eye and the size of the lens, assessment of homogeneity vitreous, retinal detachment exceptions shown holding ultrasound eyes.
Differential diagnosis between true and false myopia and transient myopia.
laser therapy, magnetic therapy, massage of cervical area, reflexology).
In the treatment of myopia used orthoptic methodology: training ciliary muscle of the negative lens, hardware and treatment (training accommodation, laser stimulation, color impulse therapy, etc.).
For the correction of myopia made selection of contact lenses or glasses with scattering (negative) lenses. To maintain a reserve accommodation with myopia, as a rule, carried out an incomplete correction. When -3 diopters of myopia above shows the use of two pairs of glasses or glasses with bifocal lenses. In high myopia glasses are selected based on their portability. For the correction of myopia orthokeratology (night) lenses can be used weak moderate.
Today Ophthalmology developed more than twenty methods and laser refractive surgery for the treatment of myopia. Excimer laser correction of myopia involves correcting vision by changing the shape of the cornea, giving it a normal refractive power. Laser correction of myopia is held with myopia up to -12-15 diopters and is performed on an outpatient basis. Among the methods of laser surgery for myopia most widely used LASIK, SUPER LASIK, EPILASIK, FemtoLASIK, LASEK, photorefractive keratectomy (PRK). These methods differ in the degree of exposure and method of forming the surface of the cornea, however, essentially identical. Complications of laser treatment of myopia can be hypo- or overcorrection, the development of corneal astigmatism, keratitis, conjunctivitis, dry eye syndrome.
By the refractive lens replacement (lensectomy) resort with a high degree of myopia (up to -20 diopters) and the loss of the natural accommodation of the eye. The method consists in the removal of the lens inside the eye and placing an intraocular lens (artificial lens) having the desired optical effect.
Implantation of phakic lens, as a method of treatment of myopia, is used in preserved natural accommodation. When this lens is not removed, but additionally, in the front or posterior chamber implants special lens. By implantation of phakic lens correction is carried out is very high (up to -25 diopters) degrees of myopia.
Radial keratotomy method due to the large number of restrictions in modern surgery of myopia is rarely used. The method involves applying to the periphery of cornea of radial non-through incisions which fusing, change shape and the optical power of the cornea.
Scleroplastic surgery for nearsightedness is carried out in order to stop the growth of the eye. During scleroplasty for fibrous tunic of eyeball infest strip biological grafts covering the eyes and prevent its extension. In the eyes of deterrence growth aims, and other operations - kollagenoskleroplastika.
In some cases, it is advisable to hold with myopia keratoplasty - transplant donor cornea, which is attached to a specific form using a software simulation.
The optimal method of treatment of myopia can be determined only qualified eye surgeon (laser surgery), taking into account the individual characteristics of visual impairment.
Prediction and prevention of myopia
With proper correction of myopia stationary most cases it is possible to maintain high visual acuity. With progressive or malignant myopia prognosis is determined by the presence of complications (amblyopia, stafilom scleral hemorrhages in the retina or vitreous degeneration or retinal detachment).
With a high degree of myopia and changes in the fundus is contraindicated in hard physical labor, heavy lifting, work associated with prolonged eyestrain.
Prevention of myopia, especially in children and adolescents, requires the development of skills of hygiene, the special exercises for the eyes and restorative measures.
Important role played by preventive examinations aimed at detection of myopia in high-risk groups, clinical examination of patients with myopia, preventative measures, rational and timely correction.