WHAT TO EXPECT DURING A COMPREHENSIVE EYE EXAM

KLEINWOOD VISION

DID YOU KNOW???

Getting your annual eye exam can detect early symptoms of diabetes, high blood pressure, shingles, tumors, stroke, high cholesterol, hypertension, arthritis, HIV… and that’s just to name a few.

Your eye are the windows to your health!

Optometrist use a wide variety of tests and procedures to examine your eyes.

Here are eye and vision tests that you are likely to encounter during a comprehensive eye exam.

SNELLEN EYE CHART The Snellen Eye Chart is the standard in

measuring the eye’s ability to distinguish detail and sharpness (visual acuity).

The chart is based on the work of a Dutch ophthalmologist, Dr. Hermann Snellen, who designed this system in 1862.

The smallest row of letters that the patient reads accurately determines visual acuity in the uncovered eye. The test is repeated with the other eye, and then with both together.

“Normal” vision is 20/20. A person who can clearly read a one-inch letter at a distance of 20 feet.

All measurements obtained from the use of the Snellen Chart are a comparison to that standard.

Persons who have 20/40 vision, for example, can read at 20 feet what people with normal vision can read at 40 feet.

COLOR BLINDNESS

A screening test that checks your color vision

In addition to detecting hereditary color vision deficiencies, color blind tests also can alert your eye doctor to possible eye health problems that may affect your color vision.

A more precise term is Color Vision Deficiency (CVD).

Color blindness can be misleading if taken literally, because colorblind people can see colors, but cannot make out the difference between some couples of complementary colors.

Red/Green color vision deficiency is by far the most common form, about 99%

Approximately 8% of all men and 0.5 percent of all women suffer from CVD.

AUTOREFRACTORS

The autorefractor has been in use since the 1970’s.

A diagnostic tool used to measure a person’s refractive error and prescription for eyeglasses or contact lenses.

The autorefractor prints a detailed reading that determines visual acuity and the need for any type of corrective lenses.

This is achieved by measuring how light is changed as it enters a person’s eye. The automated refraction technique is quick, easy, simple, and requires no feedback from the patient.

TONOMETER

A Tonometer is an instrument used to measure the pressure of the eye.

Some doctors use the air-puff tonometer, also know as non-contact tonometry, or NCT.

Based on your eye’s resistance to the puff of air, the machine calculates your intraocular pressure (IOP). If you have high pressure, you may be at risk for or have glaucoma.

VISUAL FIELDS A visual fields test is a method of measuring

an individual’s entire scope of vision, that is their central and peripheral vision. It maps the visual fields of each eye individually.

Visual field testing is most frequently used to detect any signs of glaucoma. In addition, visual fields tests are useful for detection of central or peripheral retinal disease, eyelid conditions, optic nerve disease, and disease affecting the visual pathways within the brain.

COVER TEST

While there are many ways for your eye doctor to check how your eyes work together, the cover test is the simplest and most common way.

During a cover test, your eye doctor will have you focus on a small object across the room and then they will cover each of your eyes alternately while you stare at the target.

While doing this, your eye doctor will asses whether the uncovered eye must move to pick up the fixation target, which could indicate strabismus or a more subtle binocular vision problem that could cause eye strain or amblyopia (“lazy eye”). The Test is then repeated up-close.

SLIT-LAMP EXAM

The slit lamp, also called a biomicroscope, allows your eye doctor to get a highly magnified view of the structures of your eye to evaluate your eye health and detect any signs of infection or disease.

A wide range of eye conditions and diseases can be detected with slit-lamp examination, including cataracts, macular degeneration, corneal ulcers, diabetic retinopathy, etc.

DILATION

To obtain a better view of the eye’s internal structures, your eye doctor instills dilating drops to enlarge your pupils.

Dilating drops usually take about 20 to 30 minutes to start working.

When dilated your pupils will be sensitive to light and you may notice difficulty focusing on objects up close. These effects can last for up to several hours.

Pupil dilation is very important for people with risk factors for eye disease, because it allow for the most thorough evaluation of the health of the inside of your eyes!

REFRACTION

This is the test that your eye doctor uses to determine your exact prescription.

During a refraction, the doctor puts the instrument called a phoropter in front of your eyes and shows you a series of lens choices. They will then ask you which of the two lenses in each choice looks clearer.

Based on your answers, your eye doctor will continue to fine-tune the lens power until reaching a final prescription.

The refraction determines your level of hyperopia, myopia, astigmatism, and presbyopia.