Shortsightedness (Myopia): Treatment, symptoms, advice and help
About Shortsightedness (Myopia)
Myopia is a refractive defect of the eye in which far away objects appear blurred and near objects appear clearly.
Myopia: Incidence, age and sex
Myopia (or nearsightedness) affects 20% to 30% of the population. The incidence of myopia increases during the school years, especially during the pre-teen and teen years. The degree of myopia also increases with age during the growing years.
Causes and prevention of myopia
In myopia, parallel rays of light come to focus anterior to the retina. This may result because the antero-posterior diameter of the eye is too long or the refractive power of the cornea or lens is greater than normal. In most cases, myopia is not a result of pathological alteration of the eye and is referred to as simple or physiologic myopia. A hereditary tendency to myopia is observed, and children of myopic parents should be examined at an early age. Some children may have pathological myopia, a rare condition caused by a pathologically abnormal axial length of the eye. Tears or breaks in the retina may occur as it becomes increasingly thin, leading to the development of retinal detachments. Myopia may also occur as a result of other ocular abnormalities, such as keratoconus, ectopia lentis, congenital stationary night blindness, and glaucoma. Myopia is also a major feature of the Stickler syndrome.
Signs & symptoms of myopia: Diagnosis
The principal symptom is blurred vision in relation to distant objects. The patients may complain of headaches, eyestrain, squinting or fatigue when driving, playing sports, or looking more than a few feet away. A diagnosis of myopia is typically confirmed during an eye examination by an ophthalmologist, optometrist and an orthoptist. Frequently an autorefractor or retinoscope is used to give an initial objective assessment of the refractive status of each eye, then a phoropter is used to subjectively refine the patient's eyeglass prescription.
High myopia increases the risk of retinal detachment, glaucoma and cataract.
The LASIK (laser-assisted in situ keratomileusis) procedure uses either a microkeratome or a femtosecond laser that forms an epithelial stromal flap permitting the underlying corneal tissue to be ablated to correct vision; the flap then recovers the area of the cornea. Correction of vision is usually degrees of myopia (>10 diopters).
Complications are lowest with more experienced surgeons.