(No posing or flexing required)

These tests evaluate the muscles that control eye movement. The doctor is looking for weakness, poor coordination or abnormal movement. Muscle issues could be as simple as muscle weakness or an issue such as stabismus (i.e., being cross-eyed).

Although it sounds rather technical, muscle testing is actually an essential part of a comprehensive eye exam.

This is the part of an eye exam people are most familiar with. You will read an eye chart to determine how well you see at various distances. You cover one eye while the other is being tested. This exam will determine whether you have 20/20 vision or not.

The doctor will begin with a technique called retinoscopy. This procedure measures any refractive error by evaluating the movement of a light reflected by your retina.

The doctor will then fine-tune this assessment by having you look through a phoropter. A device that contains hundreds of different lenses. He or she will then ask you to judge which combination of lenses gives you the sharpest vision.

Assessment of any refractive error found helps the doctor determine the prescription that will give you the sharpest, most comfortable vision. The assessment may also determine that you don’t need corrective lenses.

A retinal examination — sometimes called ophthalmoscopy or funduscopy — allows your doctor to evaluate the back of your eye, including the retina, the optic disk and the underlying layer of blood vessels that nourish the retina (choroid). This is important in the detection of certain systemic diseases and diseases that primarily affect the eye. Before the doctor can see these structures, your pupils must be dilated with eyedrops that keep the pupil from getting smaller when your doctor shines light into your eye.

The doctor may use one or more of these techniques to view the back of your eye:

• Direct exam. Your eye doctor uses an ophthalmoscope to shine a beam of light through your pupil to see the back of the eye. Sometimes eyedrops aren’t necessary to dilate your eyes before this exam.
• Indirect exam. During this exam, you typically lie back in the chair. The doctor examines the inside of the eye with the aid of a special lens and a bright light mounted on his forehead. This exam lets your doctor see the retina and other structures inside your eye in great detail and in three dimensions.

The slit-lamp is a low-power microscope combined with a high-intensity light source that can be focused into a thin beam. The doctor uses this device to examine the eyelids, lashes, cornea, iris, lens and fluid chamber between your cornea and iris.

The doctor may use a dye, most commonly fluorescein (flooh-RES-een), to color the film of tears over your eye. This helps reveal any damaged cells on the front of your eye.

Your visual field is how wide of an area your eye can see when you focus on a central point.

A visual field test can determine if you have blind spots (called scotoma’s) in your vision and where they are. A scotoma’s size and shape can show how an eye disease, or a brain disorder is affecting your vision.

The two most common types of visual field tests are:

• Confrontation exam. Your eye doctor sits directly in front of you and asks you to cover one eye. You look straight ahead and tell the doctor each time you see his or her hand move into view.
• Automated perimetry. As you look at a screen, lights will blink in various areas. You press a button each time you see a light blink.