Myopia
    
Share |
 
  

Diseasereference.net - Comprehensive articles covering over 1,700 topics. The articles are organized by the disease, condition overview, symptoms, treatment, and prevention.


Drugs search, click the first letter of a drug name:
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | 1 | 2 | 3 | 4 | 5 | 6 | 8 | 9

Terms search, click the first letter of a term name:
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Online medical services

Medical dictionary Med-Terms.net is a searchable dictionary of medical terms from medicine and related fields. Search for medical terms with our medical dictionary.

Drugs & Medications Search our drug database for comprehensive prescription and patient information on 24,000 drugs online. Drugspedia.net - The Internet Drug Index for prescription drugs and medications.

PMS blog Premenstrual syndrome (PMS), PMS headache


Blue waffles disease, blog. Blue waffle infection, blue waffle disease pictures.

  

 

Disease Reference

Click on the first letter in the disease name:

| 4 | 5 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z



     

Myopia

Definition

Nearsightedness is when the eyes focus incorrectly, making distant objects appear blurred.

Alternative Names

Myopia; Shortsightedness

Causes

A nearsighted person sees near objects clearly, while objects in the distance are blurred. As a result, someone with myopia tends to squint when viewing far away objects. This characteristic is the basis of the word "myopia," which comes from two Greek words: myein, meaning shut, and ops, meaning eye.

A nearsighted person can easily read the Jaeger eye chart (the chart for near reading), but finds the Snellen eye chart (the chart for distance) difficult to read. This blurred vision results when the visual image is focused in front of the retina, rather than directly on it.

It occurs when the physical length of the eye is greater than the optical length. For this reason, nearsightedness often develops in the rapidly growing school-aged child or teenager, and progresses during the growth years, requiring frequent changes in glasses or contact lenses. It usually stops progressing as growth is completed in the early twenties.

Nearsightedness affects males and females equally, and those with a family history of nearsightedness are more likely to develop it. Most eyes with nearsightedness are entirely healthy, but a small number of people with myopia develop a form of retinal degeneration.

Symptoms

  1. Blurred vision or squinting when trying to see distant objects (children often cannot read the blackboard, but can easily read a book).
  2. Eyestrain.
  3. Headaches (uncommon).

Exams and Tests

A general eye examination, or standard ophthalmic exam may include:

  1. Visual acuity, both at a distance (Snellen), and close up (Jaeger)
  2. Refraction test, to determine the correct prescription for glasses
  3. Test of color vision, to test for possible color blindness
  4. Tests of the muscles which move the eyes
  5. Slit-lamp exam of the structures at the front of the eyes
  6. Measurement of the pressure of fluid in the eyes
  7. Retinal examination

Treatment

Nearsightedness is easily compensated for by the use of eyeglasses or contact lenses, which shift the focus point to the retina. There are several surgical procedures that reshape the cornea, shifting the focus point from in front of the retina to the retina.

Radial keratotomy is a surgical procedure popular in the recent past. Now it has been almost completely replaced by LASIK, in which an excimer laser is used to reshape the cornea.

Outlook (Prognosis)

Early diagnosis of nearsightedness is important, because a child can suffer socially and educationally by not being able to see well at a distance.

Possible Complications

  1. Complications may be associated with the use of contact lenses (corneal ulcers and infections )
  2. Complications of laser vision correction are uncommon, but can be serious
  3. Although it is rare, people with myopia may develop retinal detachments or retinal degeneration

When to Contact a Medical Professional

Call for an appointment with your ophthalmologist if your child shows these signs, which may indicate a vision problem: sitting close to television, holding books very close when reading, or having difficulty reading the blackboard in school or signs on a wall.

Call for an appointment with your ophthalmologist if your child is having difficulties at school that may be caused by a vision problem.

Call for an appointment with your ophthalmologist if a person with nearsightedness experiences flashing lights, floating spots, or a sudden loss of any part of the field of vision.

Prevention

There is no way to prevent nearsightedness. Reading and watching television do not cause nearsightedness. In the past, dilating eye drops were proposed as treatment to slow development of nearsightedness in children, but they have never been proved effective.

The use of glasses or contact lenses does not affect the normal progression of myopia in the growth years -- they simply focus the light so the nearsighted person can see distant objects clearly.

Email to a Friend


Your Name:

Friend's Email:



More about Myopia - Drugs.com
   Myopia
Oppositional defiant disorder
Measles
Acute colonic ileus
Toxoplasmosis
Mallory-Weiss tear
Lactic acidosis
Night terror
Essential tremor
Perirenal abscess



 
  
Medical dictionary | Natural mosquito repellents | Dust mites pictures | Prescription Drug Information | new 401k rules | Hyperkeratosis pilaris treatment
© Copyright by Diseasereference.net 2006-2007. All rights reserved