Eye examination

A doctor can check your eyes.

They see how well you see. They check if you can see far away. They check if you can see things close up.

Doctors use charts with letters. You look at the letters to show what you see.

They also use a light. The light helps them see your pupils.

They check how your eyes move. This helps them see if your eyes work well together. They may also check the pressure inside your eye.

It is good to get these checks. They can find problems early. This helps keep your eyes healthy.

Checking your eyes helps you see the world.

An eye exam is a set of tests.

Doctors use these tests to check your vision. They see how well you focus on things. They also check the health of your eyes. Doctors like optometrists or ophthalmologists do these tests.

First, a doctor asks about your history. They ask about your past eye problems. They may ask about your family too. This helps them find risks early. Some diseases run in families.

Next, they check your visual acuity. This is your ability to see fine details.

You might look at a chart with letters. This shows if you see clearly at a distance.

Doctors also check your pupils. They use a light to see how they react. They check if your pupils are round and equal. They also check how your eye muscles move. This helps see if your eyes work together.

Finally, they check the pressure inside your eye. This is called intraocular pressure. They use a tool called a tonometer.

This test helps find problems like glaucoma. Regular exams help keep your eyes healthy.

An eye examination is a series of important tests. These tests check your vision and how well you can focus.

Doctors use them to see if you can spot objects near or far. They also look at the overall health of your eyes. Many eye diseases have no symptoms at first. This means you might not even know you have a problem. Because of this, doctors recommend regular checkups as part of routine care. Experts like optometrists, ophthalmologists, or orthoptists usually perform these exams.

A full exam follows several specific steps to be thorough. First, the doctor looks at your medical history. They ask about past injuries or surgeries like cataract surgery. They also ask about your family to find genetic risks. Next, they test your visual acuity, which is your ability to see fine details.

They might use a Snellen chart with letters or symbols. Then, they check your pupil function using a light. They look to see if your pupils are equal and round. They also test how your eye muscles move in different directions.

Finally, they may check the pressure inside your eye using a tool called a tonometer.

History shows how important these tests are for health. In the past, eye exams were used for many people.

For example, military recruits in 1917 underwent eye exams. Today, we know that certain medicines can affect the eyes. People taking hydroxychloroquine for lupus need annual exams. This is because the medicine can cause eye changes after five years. Doctors also watch for side effects from corticosteroids. These medicines can raise the pressure inside your eye.

There are many specific facts about eye health to know. A healthy person might get an exam once in their 20s. They may get them twice during their 30s. Normal eye pressure is between 10 and 21 mmHg. If a person has 20/20 vision, they see at 20 feet what a normal person sees at 20 feet. If they see at 20 feet what a normal person sees at 40 feet, it is called 20/40 vision. Some conditions, like diabetes, can lead to diabetic retinopathy. High blood pressure can also damage the tiny blood vessels in the retina.

Eye exams connect to many things you might already know. You might have worn glasses to help you see better. This is called a corrective lens. During an exam, doctors check your "best corrected visual acuity." This means the best vision you can get with glasses. They also check your peripheral vision, which is what you see out of the corners of your eyes.

This is like looking through a window. You want to make sure you can see everything around you. Keeping your eyes healthy helps you enjoy the world clearly.

An eye examination is a specialized series of clinical tests. These tests assess visual acuity and the ability to focus on near and far objects. They also evaluate the overall health of the ocular structures. Professionals such as optometrists, ophthalmologists, or orthoptists typically perform these evaluations. Regular examinations are vital because many eye diseases are asymptomatic. This means a person may have a disease without feeling any symptoms.

For a healthy individual, routine exams might occur once in their 20s and twice in their 30s.

A comprehensive eye exam begins with a detailed medical history. This is an essential first step for identifying systemic health connections. Many eye conditions are linked to diseases in other parts of the body. For example, diabetes mellitus can lead to diabetic retinopathy or early cataracts. Longstanding hypertension can cause microvascular damage in the retina, known as hypertensive retinopathy. Severe malignant hypertension can cause papilledema, which is swelling of the optic nerve. This condition is a medical emergency that can lead to blindness.

Providers also ask about personal history, such as eye trauma or previous surgeries like cataract or glaucoma procedures.

After the history, the examiner moves through specific clinical steps. The first step is measuring visual acuity, which is the ability to see fine details. This is often done using a Snellen or LogMAR chart.

If a patient cannot read the chart, clinicians use alternative methods. They might use "count fingers" (CF) or "hand motion" (HM) tests. In severe cases, they check for "light perception" (LP) or "no light perception" (NLP). Visual acuity is recorded as a fraction, such as 20/20. This means the person sees at 20 feet what a normal person sees at 20 feet.

The next step involves checking pupil function and eye movement. Doctors use the mnemonic PERRLA to check if pupils are equal, round, and reactive to light and accommodation. A swinging-flashlight test can help detect an afferent pupil defect, also called a Marcus Gunn pupil.

This test is useful for assessing optic nerve anomalies. The examiner also tests extraocular motility, which is how the eye muscles move. They check the nine cardinal directions of gaze to test muscles like the rectus and oblique muscles. They may also check saccades, which are the quick "jumps" the eyes make between targets. This helps ensure the eyes can move smoothly for tasks like reading.

Pressure within the eye must also be measured. The eye is an enclosed compartment with circulating fluid that maintains internal pressure. This is measured using tonometry. A common method is Goldmann applanation tonometry (GAT).

During this process, the clinician uses a prism to gently flatten the central cornea. The tear film is often stained with fluorescein dye to help the view. The normal range for intraocular pressure is between 10 and 21 mmHg. High pressure is a concern because certain medications, like corticosteroids, can increase it and lead to glaucoma.

Examiners also check the visual field and the external structures of the eye. Confrontational visual field testing assesses the peripheral vision.

The patient covers one eye and counts fingers flashed in different quadrants. This helps detect issues like scotoma, which is an area of reduced vision, or hemianopia, where half the field is lost. Finally, an external examination inspects the eyelids and surrounding tissues. The doctor looks for things like ptosis, which is an asymmetry in eyelid position. They may also perform a slit-lamp examination or a fundoscopic examination through a dilated pupil to see the internal structures clearly.

Understanding eye health requires looking at genetics and medication use. Certain diseases, such as glaucoma or age-related macular degeneration, often run in families.

Medications also play a significant role in eye health. For instance, patients taking hydroxychloroquine for lupus or rheumatoid arthritis need annual exams after five years of use. This is because the drug can cause ocular side effects. By combining medical history, muscle testing, and pressure measurements, eye exams provide a complete picture of ocular and systemic health.