Eye Problems Diagnosis

The purpose of diagnosing an eye problem is to confirm the underlying problem. A preliminary diagnosis is mainly done on the basis of appearance of the eye and other related physical symptoms. Various tests are required to confirm the results of the preliminary diagnosis. The treatment can be initiated only when the cause of eye problem is diagnosed.

Diagnosis of Eye Problems

Refraction
Refraction is the test to diagnose focusing errors. Vision impairments such as nearsightedness, farsightedness, astigmatism, presbyopia etc. can be diagnosed using this test. This test mainly determines the clarity of vision at 20 feet. For instance, a person with a vision 20/200 sees an object at 20 feet as clear as a person with a perfect vision of 20/20, sees at 200 feet. Snellen chart is a major tool used to determine the visual acuity of a person. This chart consists of illuminated rows of letters, arranged in a peculiar order. The chart needs to be read from a standard distance to confirm the type of focusing error. Automated refraction is done with a machine, which measures the response of an eye when a beam of light enters the eye.

Visual Field Testing
Visual field testing involves finding out the scope of vision of the person, including the peripheral vision. Visual scope of each eye is determined separately in this test. Visual field testing may often be a part of routing eye testing. However, sometimes visual testing has to be done in detail, if a person complains of a peculiar vision field problem. For instance, if a person keeps on bumping on objects that are on one side, then visual field testing may be required to confirm the cause. Visual field testing can be done manually as well as using devices such as Amsler grid or Goldmann perimeter.

Ophthalmoscopy
Ophthalmoscope is a hand-held device which resembles a small flashlight with magnifying lenses. A beam of light is shone directly in the eye of the person, so that the ophthalmologist can study various components of eye such as cornea, lens, vitreous humor, retina, optic nerve and the retinal veins and arteries. Often eye drops are used to dilate the pupils, so as to get a better view of the eye. A person may experience a few side effects of the eye drops such as blurring of vision and increased sensitivity to light, for few hours. Ophthalmoscopy is often a part of routine physical examination.

Electroretinography
This test is performed to examine the functionality of photoreceptors, which are the light sensing cells in the eye. A recording electrode which is in the form of a contact lens is placed on the dilated cornea. The other electrode is located somewhere on face, preferably cheeks. The room is darkened and the flashes of light are frequently shone in the eye. The response of eye, in terms of electrical activity is recorded by the electrodes. This method is most effective in the diagnosis of diseases such as retinitis pigmentosa.

Computed Tomography and Magnetic Resonance Imaging
These tests provide the detailed computerized images of the internal structure of the eye. They are effective in locating any foreign objects in the eye. They are also useful for studying the bony structures around the eye.

Accurate eye problems diagnosis is important for effective treatment. Often, eye problems are not of serious consequence, but it is always wiser to get yourself routinely examined to detect and correct such problems on time.