a professional optometrist is doing an eye test to a middle-aged man

/ CHILDREN'S VISION DEVELOPMENT

Eye Exams for All Ages

For both adults and children alike, eye exams are an important part of one’s general health maintenance and assessment. Your eyes should be checked regularly to ensure that you are able to see as best as possible.

Regular eye health exams will also check for signs of eye disease or conditions that can affect not only your vision but your overall health. Vision and eye health is such a critical part in learning and development, therefore, we highly recommend eye exams for infants and children.

/ PROFESSIONAL EYE EXAMINATION

The Importance of Eye Exams

Vision screening vs. an eye exam

When we recommend regular eye exams, this should not be confused with a vision screening. A vision screening is a basic test that indicates if you have difficulty seeing and require further assessment and corrective measures. It can be performed by anyone, whether it is a school nurse, a pediatrician or even a volunteer at a vision clinic. A vision screening usually only checks vision, it does not check eye health. Also, most vision screenings for kids only check for nearsightedness (when you can not see far), but what happens when the majority of children are farsighted? Most of the time many of these kids get overlooked.

A comprehensive eye exam on the other hand, can only be performed by an eye doctor as it requires special knowledge and equipment to look around and into your eye to check your eye and vision health. Such an exam can assess whether there are underlying causes for vision problems and whether there are any signs of disease which can threaten your site and the health of your eye. A comprehensive eye examination can also diagnose symptoms of diabetes, high blood pressure, high cholesterol, tumors, cancer, autoimmune disorders, and thyroid disorders. A comprehensive eye examination will also provide an accurate prescription for eyeglasses or contact lenses.

Eye exams for eye health

Eye exams are critical because many vision threatening eye diseases such as glaucoma, macular degeneration, cataracts, or diabetic retinopathy have no or minimal symptoms until the disease has progressed. In these cases, early detection and treatment is essential to halting or slowing down the progression of the disease and saving eyesight. During a comprehensive eye examination, your eye doctor will be looking for initial signs of these diseases. If a problem with your eyes arises such as red eyes, eye allergies, dry eyes, eye swelling,eye pain, always seek an eye doctor as your first doctor to call since they are specifically trained to treat eye diseases.

Eye exams and children

If your child is having developmental delays or trouble in school there could be an underlying vision problem. Proper learning, motor development, reading, and many other skills are dependent upon not only good vision, but your eyes functioning together. Children that have problems with focusing or hand-eye coordination will often experience frustration and may exhibit behavioral problems as well.

Often they don’t know that the vision they are experiencing is abnormal so they aren’t able to express that they need help. Many conditions are much easier to treat when they are caught early while the eyes are still developing, so it is important to diagnose any eye health and vision issues as early as possible.

Eye exams over 40

Just like the rest of our bodies, our eyes begin to weaken as we age. There are a number of common age-related eye conditions such as presbyopia, cataracts, and age-related macular degeneration that can begin to affect your vision and your daily life. While some of these conditions are more of an inconvenience, others could lead to vision loss and dependency.

In addition to regular yearly eye exams, it is important to be aware of any changes in your eye health and vision. Also know your potential risk factors as well as your family ocular and medical history. Over half of the vision loss worldwide is preventable with proper treatment and care.

What to expect

For regularly scheduled eye exams, expect to talk about any changes in your medical history since the last time you saw your eye doctor. And if this is your first time in a new practice, you’ll be asked to provide a more complete medical history, including a list of medications you’re currently taking, and any vision problems your parents may have experienced.

In addition, you’ll undergo a series of vision and eye tests that help determine the overall health and quality of your vision. These tests also help to check that your current prescription glasses or contacts (if you have one) is still meeting your vision needs. Your eye doctor will also check your eyes for signs of any potential vision problems or eye diseases. In many instances, your pupil may be dilated (opened) using special drops so that your eye doctor can better see the structures of the eye.

You’ll then have an honest discussion about the current state of your eye health and vision, and your eye doctor may “prescribe” vision correction for you in the form of eyeglasses or contact lenses. Any health concerns or possibly serious vision complications will also be discussed, including the next steps you must take to preserve and protect your sight.

In general, a routine eye exam will last less than an hour depending upon the number of tests you have, and may be partially or completely covered by many vision insurance plans.

Visiting eye doctors as a result of a vision screening is also common, but remember: vision screenings offered by health clinics, pediatricians, public schools or local charitable organizations are not a substitute for comprehensive eye exams. Be sure to bring the findings from your screening to your eye doctor—it’s a great way to begin the discussion of your current eye health.

For eye doctor visits that result from eye pain, eye discomfort or vision problems you actually can see, expect to take many of the steps involved in a routine eye exam, but specific to the symptoms you’re having. There may be a number of additional tests required as well, so it’s important—especially when suffering pain or discomfort—to allow for as much time as possible for a complete, comprehensive eye exam.

And if you feel you are in an emergency situation with your eyes or your vision—don’t wait. Seek immediate emergency medical treatment.

Remember the following for your next eye doctor visit:

  • Know your medical history and list of current medications
  • Know your current symptoms and be able to describe them—write them down if necessary
  • Know your family history—some eye diseases like glaucoma and cataracts are hereditary
  • Ask in advance about your particular vision insurance plan, and if a co-pay will be due
  • Bring your insurance card, identification and method of payment, if necessary
  • Bring your most recent prescription for glasses or contact lenses
  • Bring your corrective eyewear to the exam
  • If undergoing a test using dilation eye drops, bring proper eye protection, like sunglasses, for after your appointment

Most importantly, remember that eye doctors—and everyone within the eyecare practice—are there to help you see your best and feel your best.

What to ask

It’s essential, too, that you make the most out of your exams. We’ve included a range of questions for you to ask during your next eye exam, or if necessary, before your exam to avoid any miscommunication. We hope you find these helpful and that the information contained in our EyeGlass Guide 2.0 will help to facilitate a comprehensive and informed dialogue between you and your eye care professional.

Questions to ask before your eye exam…

  • Do you accept my insurance plan’s vision coverage?
  • Is payment required at the time of service?
  • What will my eye exam entail?
  • How long should I expect to be there?
  • Will my pupils be dilated?
  • What should I bring with me?

Questions to ask at your eye exam…

  • Given my age, eye condition and other risk factors, how often should I have my eyes examined?
  • At what age should I start to schedule my children for regular eye exams?
  • What lens designs and options are a good fit for me?
  • Can my glasses block UV rays?
  • Do all sunglasses protect my eyes from UV rays?
  • What are photochromic lenses and are they a good option for me?

Things to remember

It’s always a good idea to bring any of the following (if available) to your eye exam appointment:

  • Your insurance card/insurance information
  • A list of all medications, vitamins and other supplements you are taking
  • All pairs of prescription glasses you currently own
  • If you have it, a copy of your latest eyeglass prescription
  • Information on frames you like, or lenses you’ve researched

Don’t forget, if participating in a flexible spending account program, you may be able to use the account to pay for portions of your eye care not covered directly by your insurance plan.

To create a printable personal eyeglass suggestion based on your own preferences and lifestyle, use our interactive tool.

  • + For Contact Lenses
  • + Preparing for an Eye Exam
  • + Comprehensive Eye Exam
  • + Common Tests
  • + Medications
+ For Contact Lenses
a pair of contact lenses

/ CONTACT LENSES

Eye Exams for Contact Lenses

Contact lenses are a great alternative to wearing eyeglasses. An often unknown fact is that not all patients wear contact lenses as their primary source of vision correction. Each patient is different, with some patients wearing contact lenses only on weekends, special occasions or just for sports. That is the beauty of contact lens wear, the flexibility it gives each individual patient and their lifestyle.

If you decide to opt for contact lens wear, it is very important that the lenses fit properly and comfortably and that you understand contact lens safety and hygiene. A contact lens exam will include both a comprehensive eye exam to check your overall eye health, your general vision prescription and then a contact lens consultation and measurement to determine the proper lens fit.

The importance of a comprehensive eye exam

Whether or not you have vision problems, it is important to have your eyes checked regularly to ensure they are healthy and that there are no signs of a developing eye condition. A comprehensive eye exam will check the general health of your eyes as well as the quality of your vision.

During this exam the eye doctor will determine your prescription for eyeglasses, however this prescription alone is not sufficient for contact lenses. The doctor may also check for any eye health issues that could interfere with the comfort and success of contact lens wear.

The contact lens consultation

The contact lens industry is always developing new innovations to make contacts more comfortable, convenient and accessible. Therefore, one of the initial steps in a contact lens consultation is to discuss with your eye doctor some lifestyle and health considerations that could impact the type of contacts that suit you best.

Some of the options to consider are whether you would prefer daily disposables or monthly disposable lenses, as well as soft versus rigid gas permeable (GP) lenses. If you have any particular eye conditions, such as astigmatism or dry eye syndrome, your eye doctor might have specific recommendations for the right type or brand for your optimal comfort and vision needs.

Now is the time to tell your eye doctor if you would like to consider colored contact lenses as well. If you are over 40 and experience problems seeing small print, for which you need bifocals to see close objects, your eye doctor may recommend multifocal lenses or a combination of multifocal and monovision lenses to correct your unique vision needs.

Contact lens fitting

One size does not fit all when it comes to contact lenses. Your eye doctor will need to take some measurements to properly fit your contact lenses. Contact lenses that do not fit properly could cause discomfort, blurry vision or even damage the eye. Here are some of the measurements your eye doctor will take for a contact lens fitting:

  • Corneal Curvature

In order to assure that the fitting curve of the lens properly fits the curve of your eye, your doctor will measure the curvature of the cornea or front surface of the eye. The curvature is measured with an instrument called a keratometer to determine the appropriate curve for your contact lenses. If you have astigmatism, the curvature of your cornea is not perfectly round and therefore a “toric” lens, which is designed specifically for an eye with astigmatism, would be fit to provide the best vision and lens fit. In certain cases your eye doctor may decide to measure your cornea in greater detail with a mapping of the corneal surface called corneal topography.

  • Pupil or Iris Size

Your eye doctor may measure the size of your pupil or your iris (the colored area of your eye) with an instrument called a biomicroscope or slit lamp or manually with a ruler or card. This measurement is especially important if you are considering specialized lenses such as Gas Permeable (GP) contacts.

  • Tear Film Evaluation

One of the most common problems affecting contact lens wear is dry eyes. If the lenses are not kept adequately hydrated and moist, they will become uncomfortable and your eyes will feel dry, irritated and itchy. Particularly if you have dry eye syndrome, your doctor will want to make sure that you have a sufficient tear film to keep the lenses moist and comfortable, otherwise, contact lenses may not be a suitable vision option.

A tear film evaluation is performed by the doctor by putting a drop of liquid dye on your eye and then viewing your tears with a slit lamp or by placing a special strip of paper under the lid to absorb the tears to see how much moisture is produced. If your tear film is weak, your eye doctor may recommend certain types of contact lenses that are more successful in maintaining moisture.

  • Contact Lens Trial and Prescription

After deciding which pair of lenses could work best with your eyes, the eye doctor may have you try on a pair of lenses to confirm the fit and comfort before finalizing and ordering your lenses. The doctor or assistant would insert the lenses and keep them in for 15-20 minutes before the doctor exams the fit, movement and tearing in your eye. If after the fitting, the lenses appear to be a good fit, your eye doctor will order the lenses for you. Your eye doctor will also provide care and hygiene instructions including how to insert and remove your lenses, how long to wear them and how to store them if relevant.

  • Follow-up

Your eye doctor may request that you schedule a follow-up appointment to check that your contact lenses are fitting properly and that your eyes are adjusting properly. If you are experiencing discomfort or dryness in your eyes you should visit your eye doctor as soon as possible. Your eye doctor may decide to try a different lens, a different contact lens disinfecting solution or to try an adjustment in your wearing schedule.

+ Preparing for an Eye Exam
an ophtalmologist is explaining the eye shape to an elder man

/ EYE EXAM IN SAN FRANCISCO

Preparing for an Eye Exam

For both adults and children, an eye exam is a critical part in maintaining your overall health and well-being, and therefore, regular eye exams should be incorporated into your health routine. Comprehensive eye exams assess your vision and the health of your eye, looking for early signs of disease that may not have obvious symptoms. You should not wait until you experience a vision problem or symptoms of an eye condition to schedule a routine exam.

Depending on your age, family history, general health and eye health, it is recommended to have an eye exam every one to two years. Of course if you experience any serious symptoms that affect your eyes or your vision, you should contact your eye doctor immediately.

The difference between an optometrist (OD) and an ophthalmologist (MD or DO)

Confusion about the difference between optometrists and ophthalmologists is common, and many people are not aware of how the two eye care professionals differ.

Optometrists

Optometrists or Doctors of Optometry attend optometry school which is usually at least four years of graduate level training. They are able to perform eye exams, provide prescriptions for eyeglasses and contact lenses, and diagnose and treat eye diseases as as glaucoma, dry eyes, or eye infections that may require medication or drops. They can consult with and co-manage patients in pre- or post-op surgical care, however they do not perform surgery.

Ophthalmologists

Ophthalmologists are medical doctors that attend medical school and later specialize in ophthalmology. They are able to do all of the services mentioned above but also perform eye surgeries such as cataract surgery, refractive surgery such as LASIK and deal with more urgent eye conditions such as retinal detachment.

Infant and child eye exams

According to the American Optometric Association (AOA) children should have their eyes examined by an eye doctor at 6 months, 3 years, at the start of school and then at least every 2 years following. If there are any signs that there may be a vision problem or if the child has certain risk factors (such as developmental delays, premature birth, crossed eyes, family history or previous injuries) more frequent exams are recommended. A child that wears eyeglasses or contact lenses should have his or her eyes examined yearly.

Adult eye exams

Healthy adults under 40 with good vision and who do not wear eyeglasses or contact lenses are recommended to have an eye exam at least every two years. Those that do use vision correction or have a health issue such as diabetes, high blood pressure or another health condition that can have an impact on your eye health should schedule a yearly exam, unless the eye doctor recommends more frequent visits.

Once you reach 40, you become susceptible to a number of age-related eye conditions such as presbyopia, cataracts or macular degeneration, therefore annual or bi-annual exams are strongly recommended.

As you continue to age, particularly after age 55, the risks of eye disease increase, and early detection can be critical to preventing significant vision loss or blindness. Scheduling a yearly eye exam can make all the difference in maintaining your independence and quality of life.

How to prepare for your eye exam

Prior to your exam you should decide whether you will be seeking special services such as a contact lens exam or LASIK consultation. These services may cost extra. Check with the doctor’s office or your insurance provider to see if they cover any of the exam expenses.

You need to know if you have medical insurance, vision plan coverage or both. Medical insurance usually does not cover “wellness/refractive” exams for glasses or contact lenses. Vision plans will cover exams for glasses or contacts, but usually cannot be used for red eyes, floaters, or other medical eye health problems. Please bring your insurance cards with you.

In addition to bringing your current pair of glasses or contacts if applicable, it is important to be aware of your personal and family history and to have a list of medications or supplements you are currently taking. Your pupils will probably be dilated as apart of your exam, so plan accordingly.

+ Comprehensive Eye Exam
a professional opthalmologist is doing an eye examination to a woman

/ COMPLETE EYE EXAMINATION

Your Comprehensive Eye Exam

Your eyes are one of the most complex organs in your body. A comprehensive eye exam to assess your visual system and eye health involves a number of different of tests. Unlike a simple vision screening, which only assesses your vision, a comprehensive eye exam includes a battery of tests in order to do a complete evaluation of the health of your eyes and your vision.

The tests that you will undergo in a comprehensive eye examination may vary from eye doctor to eye doctor but here are are some common exams that you may encounter:

Patient background and history

One of the most important parts in a comprehensive eye exam is your patient health history. This information will alert your doctor to any conditions that should be monitored closely, such as an allergy to any medications, current or family history of systemic or eye pathology or environmental conditions that could be affecting your vision or eye health. This will also help your doctor to determine any preventative eye care measures that are relevant to keep your eyes healthy for years to come.

Visual acuity

Visual acuity is a measurement of your vision using an eye chart, the Snellen Eye Chart. In this test the patient is seated at a standard distance and is asked to read letters or symbols of various sizes, which get smaller as you move down the chart. The results are the familiar ratio of 20/20, 20/40 etc. which is a comparison of your vision compared to the average person with good vision, which is typically 20/20.

For example, a patient that has 20/40 vision, can only see at 20 feet what the normal person can see from a distance of 40 feet. This test is a preliminary test of how clearly you are seeing in each eye but it does not give you a prescription for corrective lenses.

Refraction

Those who don’t have 20/20 vision have what is referred to in most cases as a “Refractive Error.” The patient may have nearsightedness, farsightedness, astigmatism or other eye conditions that prevent the patient from seeing 20/20. A refraction will tell the doctor which prescription lenses will correct your eyesight to achieve 20/20 vision or whichever amount your vision is correctable to.

Retinoscopy

Retinoscopy is a test that allows the doctor to obtain an approximate prescription for eyeglasses. In this test the doctor uses a hand-held instrument called a retinoscope that shines a light into the patient’s eye. The doctor then analyzes the reflex of the light from the patient’s eye to determine the patient’s prescription for glasses.

An instrument called a phoropter is something most patients associate with an eye exam. This space age appearing instrument, positioned in front of the patient’s face during the eye exam, gives the doctor the ability to determine the patient’s focusing ability as well as their eye alignment. The phoropter also determines which, out of the hundreds and hundreds of potential eyeglass prescriptions, will help the patient see as clear as possible. Using the phoropter, the doctor will ask the patient which series of lenses makes their vision the clearest.

While retinoscopy is quite effective for children and nonverbal patients, there are now a number of computerized or automated instruments available today to help doctors accurately determine a patient’s eyeglass prescription.

Autorefractors and aberrometers

Autorefractors and aberrometers are computerized machines that are able to measure your refractive error to determine your prescription for glasses or contact lenses. These instruments are usually used in addition to testing described earlier:

  • An autorefractor is similar to retinoscopy, which electronically analyses the light reflex from the patient’s eye.
  • An aberrometer measures distortions or aberrations in the cornea and lens of the eye that disrupt proper focus of light on the retina. Using wavefront technology, the instrument measures the rays of light as they pass through your eye to look for imperfections which may indicate a refractive error.

Eye focusing and eye teaming test

During the comprehensive eye exam, your eye doctor will also want to test how your eyes function individually and together from a mechanical perspective. In order to see clearly and comfortably, your eyes need to work together as a team.

Eye health

The final and most important aspect of a comprehensive eye exam is a check of your overall eye health. These tests (below) are done to identify any eye conditions or diseases, both inside the eye as well as the external parts of the eye, that could affect your vision and general health.

  • Slit Lamp Test

The slit lamp or biomicroscope is an instrument that allows the doctor to examine the internal and external parts of the eye in detail, such as the conjunctiva, iris, lens, cornea, retina and the optic nerve. The patient rests their forehead and chin on a headrest to stabilize the head, while the doctor looks into the eye with the slit lamp microscope, which is magnified with a high-intensity light. A slit lamp test enables the doctor to evaluate the eyes for signs of normal aging and eye pathology, such as conjunctivitis, cataracts, macular degeneration or retinal detachment. Early diagnosis and treatment of eye diseases are essential for preventing vision loss.

  • Tonometry

Tonometry is a test to detect glaucoma by measuring the pressure inside your eye or IOP (intraocular pressure). Glaucoma can cause vision loss and even blindness if the IOP in the eye is too high and damages the optic nerve.

The applanation tonometer, typically attached to a slit lamp, is one of the most common instruments used to measure the pressure in the eye. Prior to doing this test the doctor will numb the patient’s eyes using an anesthetic, before gently applanating (putting pressure on) the patient’s cornea to measure the pressure in the eye.

  • Pupil Dilation

During your comprehensive eye exam, your doctor may decide to do a dilated eye exam. In this test, your doctor will instill dilating drops in each eye, which would enlarge your pupils to give the doctor a better view of certain parts of the back of the eye. Dilation is done at the discretion of the doctor, with some patients dilated every year and others at specified intervals; the frequency of dilation will vary for each patient.

Typically the drops take around 20 to 30 minutes to take effect and may last up to several hours following the exam; each patient is different. Since more light enters your eyes when your pupils are dilated, you will be more sensitive to bright light, especially sunlight. Although your doctor may provide disposable sunglasses, you may want to bring a pair of sunglasses to wear after the exam to make it more comfortable until the drops wear off.

A comprehensive eye exam is an important part of your overall general health maintenance and should be scheduled on a regular basis. The findings from your comprehensive eye exam can give your doctor important information about your overall health, particularly diabetes and high blood pressure.

+ Common Tests
a middle-aged woman getting her eyes tested

/ EYE TEST IN SAN FRANCISCO

Common Eye Tests

While there are some basic eye vision tests common to most eye exams, children and young adults have different vision testing needs than say, a healthy middle-aged adult, or an adult with a history of eye problems.

Vision testing equipment ranges from simple tools like the “Big E” eye chart (Snellen Chart) and a hand-held penlight and eye cover, to more complex devices that swap lenses in front of your eyes or use special lamps to view the eye’s structure.

A comprehensive eye exam includes vision testing, and vision testing equipment that is common to almost all eye exams, but is often tailored to your age, your specific need, or your individual symptoms. The following are some common tests you may be given during a routine eye exam.  

Autorefractor

If you’ve discovered you might need vision correction during your eye examination, it’s vital to determine just how “much” your eyes need to be corrected with lenses or contact lenses. This is called measuring your “refraction.

Autorefractors automatically measure this value during an eye examination.

While seated with your chin in a stabilizing chinrest, you’ll be asked to focus on an image or point of light. The autorefractor automatically determines the correction needed to place your “focus point” on top of the retina, the light-sensitive area at the back of the eye responsible for correctly processing images.

The measurement taken by an autorefractor can be translated into a prescription for eyeglasses.

In eye exams for small children, or for people with special needs who may have trouble sitting calmly during an extended exam, or verbally describing their vision problems—autorefractors give highly accurate measurements used to determine vision correction needs, automatically.

How do autorefractors work?

Autorefractors only take a few moments to determine each measurement for each eye. What’s more, autorefractors are quite reliable and are sometimes used in conjunction with a machine called a phoroptor to manually switch lenses in front of your eyes to provide ideal vision correction.

Eye dilation

A truly comprehensive eye exam almost always includes eye dilation—the addition of special eye drops that “open up” the pupil at the front of the eyeball. This allows for a maximum amount of light to enter the eyeball, giving your eye doctor the best possible visibility during a variety of specific eye tests.

Eye dilation is common during an eye exam after preliminary testing of visual acuity, pressure testing, and any vision-correction measurements have been taken. Your eyes are dilated using special drops, by far the most effective way to examine the structures inside the eye, and the light-sensitive retina at the back of the eye.

Most eyecare professionals agree: eye dilation is a critical component of a comprehensive eye exam, and vital to the detection of symptoms of eye disease like macular degeneration, diabetic eye disease, glaucoma, cataracts and more.

Having your eyes dilated doesn’t hurt—it just feels a little strange. Your pupil at the front of your eye automatically adjusts to light intensity, closing when light is more intense, and opening in lower lighting conditions—much like an automatic camera adjusts to take photos indoors or outdoors.

The drops used to dilate your eyes don’t wear off immediately, that’s why it’s recommended you bring sunwear with you to a comprehensive eye exam. And if you’re driving, you may want to consider having a friend with you to help you drive home, or assist you if you feel slightly disoriented. (Remember, your eyes won’t automatically adjust to changing light conditions until the drops wear off.)

Can I have an eye exam without having my eyes dilated?

In short, yes. Most vision screenings done at a pediatrician’s office, health clinic or community health organizations don’t include eye dilation. But these basic vision tests cannot help you diagnose eye disease, and are certainly no substitute for a regular and thorough eye exam from a qualified eyecare professional.

Most eye doctors will tell you with very few exceptions, dilated eyes mean the best possible eye exam environment.

Glaucoma test

Glaucoma is the generalized name for a group of eye diseases that damage the optic nerve of the eye, preventing the eye from sending accurate visual information to the brain.

Glaucoma tests are designed to test your eyes for one of the key symptoms of the disease—increased eye pressure—however only a comprehensive eye exam can reveal whether or not you have glaucoma.

Increased pressure inside the eye is often a key indicator of glaucoma, though not exclusively so. Eye doctors can use a number of tests for eye pressure, but will, by default, check for signs of glaucoma as part of a detailed examination of the retina—the light sensitive area at the back of the eye responsible for processing images.

How Does Glaucoma Testing Work?

A glaucoma test is usually part of a routine eye exam. Both types of glaucoma tests measure internal pressure of the eye.

One glaucoma test involves measuring what happens when a puff of air is blown across the surface of the eye. (A puff test) Another test uses a special device (in conjunction with eye-numbing drops) to “touch” the surface of the eye to measure eye pressure.

While increased eye pressure is a key indicator of the disease, it does not necessarily mean you have a glaucoma diagnosis. In fact, the only way to detect glaucoma is to have a detailed, comprehensive eye exam that often includes dilation of the pupils.

So “true” glaucoma testing actually involves examining the retina and optic nerve at the back of the eye for signs of the disease.

Glaucoma can cause slight to severe vision loss, and is often discovered only after the disease is present—that’s why glaucoma testing is so important.

Ophthalmoscope

While an ophthalmoscope may seem similar to the retina scope, it has a different purpose. This is a handheld device that combines a light source with built-in mirrors and lenses so that your eye doctor can examine the interior structures of the eye. An ophthalmoscope is particularly useful for examining the structures of the retina—the light sensitive area at the back of the eye responsible for processing images.

Traditionally part of almost every eye exam, ophthalmoscopes can identify healthy structures within the eyeball, and easily help your eye doctor see symptoms or indicators of diseases of the eye.

In some instances, your eye doctor will use an indirect ophthalmoscope to gain a broader view of your eye’s internal structure, especially the retina.

With indirect ophthalmoscopes, your eye doctor wears a head visor (like a jeweler) that projects a bright light. By holding different handheld lenses in front of your eye, your doctor can better see, and magnify, the inside of your eye.

How does an ophthalmoscope it work?

Your eye doctor will dim the lights of the room and ask you to focus on a fixed point on a far wall. Using direct or indirect ophthalmoscopes, your eye doctor will examine the structures of your eye. Sometimes, special drops are used to “open up” (dilate) your pupils to aid your eye doctor in the exam.

Your eye doctor is looking for signs of a healthy retina, and also for indicators of any number of potential eye problems like cataracts or macular degeneration.

Optomap

For many eyecare patients, having pupils dilated (opened up) using eye drops can be a bother. But as an integral part of a truly comprehensive eye exam, those drops are highly recommended. Dilation gives your eye doctor the widest view of the internal structures at the back of the eye—the optic nerve, retina, even blood vessels.

That’s where Optomap technology comes in. Using low-power laser technology, your eyecare professional can take a wide, instantly-viewable and detailed digital scan of your retina (the area responsible for processing images). All in real time. And in no time. Without the use of pupil-dilating eye drops.

How does Optomap work?

It’s very similar to sitting down in a type of photo booth and leaning forward to have your picture taken. Except in this instance, the picture being taken is a larger, wide-field image of the inside of your eyeball. Optomap takes around a minute.

Since retina scanning is so important in the early detection of cataracts, diabetic eye disease, glaucoma, age-related macular degeneration and more, it’s pretty easy to see why Optomap technology is so promising.

Optomap retinal exams are not available everywhere, however. And in some instances, these scans may not be covered by traditional insurance due to cuts in eye doctor reimbursements.

Check with your eyecare professional and ask if an Optomap eye exam is right for you.

Peripheral vision test

As part of a comprehensive eye exam or vision screening, eye doctors almost always include a peripheral vision test. Your peripheral vision is the visual field at the “outside” of your vision. That means, while your eyes may be “focused” on an object directly in front of you, you should still have the ability to see and recognize objects to your left, right, up and down—not directly in your line of sight.

Since peripheral vision loss can be a sign of a number of eye diseases, including glaucoma and other optic nerve disorders, side vision must be tested regularly.

How does a peripheral vision test work?

A peripheral vision test takes little time and is usually incorporated into the early portion of the eye exam. The most common type of peripheral vision testing is “confrontational” peripheral vision testing, where your eye doctor asks you to focus on a target directly in front of you (the doctor’s eye, or an upraised finger, for example). With one eye covered, and your focus trained on the target, you’ll be asked to describe things you see in the “side” of your vision.

What’s important to remember is to keep focus on the main target and honestly describe what you see. You’ll then cover the other eye and repeat the procedure.

Peripheral vision loss indicates there may be an eye problem present, one that can then be tested for in greater detail during your eye examination.

There are additional types of peripheral vision testing using automated machines with a series of blinking lights in the outer visual field, or special cards with specific lines and patterns that create forced optical illusions.

No matter what the form of test, know that peripheral vision loss is a serious symptom that needs to be evaluated by a qualified eyecare professional.

Phoropter

If, during an eye examination, your doctor has discovered a vision problem like nearsightedness, farsightedness or astigmatism, it’s likely that one of the next steps you’ll take will involve a phoropter. A phoropter is special machine used to switch multiple lenses in front of your eyes to correct your vision.

Phoropters look imposing—like space-age visors—but are really an ingenious way to quickly determine the exact vision correction needed by your individual eyes.

By having you look through the phoropter at a visual reference, image, or the “Big E” chart (the Snellen chart), your eye doctor will help guide you toward lenses that correct your vision impairment by switching lenses within the machine on the fly.

How does a phoropter work?

The process of switching lenses in front of your eyes is less involved than it may look, given the imposing nature of the device. A phoropter is used to manually determine “refraction”—exactly how a lens must be shaped and curved to correct your vision to a normal state, nothing more.

Phoropters are subjective however, based on your visual perception and response to your eye doctor’s questions. Is your vision better, or worse? With this lens, or this lens? How about now?

There are other procedures and technologies available that automatically measure the refraction needed within your eye and produce a “prescription” measurement without your input. These are called autorefractors and aberrometers.

Puffer Test

Most people who’ve had a comprehensive eye exam are familiar with the puffer test. A puffer test is what it sounds like: With your head resting in the chinrest of a diagnostic machine called a slit lamp, your eye doctor uses a puff of air across the surface of the eye to measure the intraocular pressure, “inside” pressure, of the eye.

High pressure is a key indicator of glaucoma, a series of eye diseases that attacks the optic nerve.

How does a puffer test work?

Puff tests are quick and largely without discomfort. You’ll look at a light inside the machine while your eye doctor blows a gentle puff of air across the surface of your open eye. A device called a tonometer measures the eye’s resistance to the air, and calculates your internal eye pressure.

This usually takes only a few moments, and while your eye might water slightly, the procedure is generally over before you know it!

A puffer test is a part of glaucoma testing, and is a routine part of a comprehensive eye exam. Glaucoma is a serious disease of the optic nerve, and often doesn’t present itself until vision becomes impaired—that’s why it’s so important to have a puffer test to measure your intraocular pressure.

Retina Scope

A retina scope is a handheld device used by eyecare professionals to determine whether your eyes are “20/20,” or have difficulties in seeing things up close or far away. Technically speaking, retina scopes help eye doctors determine if you have “refractive errors” like nearsightedness or farsightedness.

By shining a light back and forth across your eye, eye doctors are able to determine (usually with great accuracy) if your vision needs corrective lenses by “dialing” the retina scope so that the light focuses properly at the back of the eye on the retina. The measurement taken by retina scopes is often the first step toward using other calibrated eye exam equipment (phoropters and slit lamps, for example).

A retina scope is particularly handy for examining younger children and people with special needs who might have problems accurately describing “what’s wrong” with their vision. In addition, retina scopes can be used to test how well your eyes work together.

How does a retina scope work?

Your eye doctor will dim the lights of the room and ask you to focus on a fixed point on a far wall. The eye doctor scans the light of the retina scope back and forth across your eyes as fine adjustments are made to the lenses in the retina scope’s light source.

This usually takes only a few moments, and while your eye might water or tear slightly, the procedure is generally over before you know it.

If your eye doctor discovers a potential vision problem, you’ll likely be asked to use other equipment to determine the exact prescription you need for corrective lenses, and look for general indicators of eye health, or potential eye problems.

Other high-tech equipment like autorefractors are becoming more common as well, as they take retinoscope measurements automatically in just a few seconds.

Retinoscope

A retinoscope is a handheld device used by eyecare professionals to determine whether your eyes are “20/20,” or have difficulties in seeing things up close or far away.

By shining a light back and forth across your eye, eye doctors are able to determine (usually with great accuracy) if your vision needs corrective lenses by “dialing” the retinoscope so that the light focuses properly at the back of the eye on the retina. This simple procedure is called a retinoscopy.

During a retinoscopy, if light focuses in front of or behind your retina, you have what is called a “refractive error” of the eye. This means you may have difficulty seeing things up close (farsightedness) or difficulty seeing things in the distance (nearsightedness). And means you likely need prescription lenses or contact lenses.

Many times, your eye doctor can determine your exact prescription by using only a retinoscope, though other equipment during an eye exam will be used to completely study your eye health, and verify any refractive errors that require you to get glasses or contact lenses.

How does a retinoscope work during retinoscopy?

Retinoscopy is a relatively quick and pain-free procedure, though your eyes may water or tear up slightly when exposed to the light within the retinoscope.

Other high-tech equipment like autorefractors are becoming more common as well, as they take retinoscopy measurements automatically in just a few seconds.

The retinoscope is a handy examination tool that can automatically detect a possible vision problem. A retinoscopy can be especially good for young children or people with special needs who might have problems accurately describing “what’s wrong” with their vision.

Slit lamp exam

If you’ve ever had a comprehensive eye examination, chances are you’ve had a slit lamp exam. Slit lamp tests are designed to help your eye doctor magnify and examine the eye from front to back.

With your head resting in a machine called a slit lamp, your eye doctor can use a combination of bright light and different magnifying lenses to view your eye’s structure. A slit lamp examination helps your eye doctor see the entire physical structure of your eye from the inside.

A slit lamp test is designed to have your eyes tell a story that might indicate the presence of many types of eye diseases and potential vision problems.

How does a slit lamp exam work?

A slit lamp examination is relatively quick and largely without discomfort, though your eye may tear or water and you’ll have to resist the urge to blink frequently.

With your head resting in the chin rest of the slit lamp, you’ll look at a light inside the machine while your eye doctor performs a meticulous scan of your eyes using different lenses, much like on a microscope. Slit lamp tests are ways to magnify what’s happening on the surface of your eye, at the front of the eye, inside the eye, and at the all-important retina at the back of the eye.

A slit lamp test is one of the most common procedures in a comprehensive eye exam because it tells your eye doctor so much about the state of your eye health, and can be used to spot indicators of a wide variety of diseases and conditions including cataracts, glaucoma, diabetic eye disease, age-related macular degeneration, even blood disorders and certain cancers.

Snellen chart

Hopefully by now, we’ve all seen one. The projected or wall-mounted Snellen eye chart, usually topped by the big letter “E”, is a common visual acuity test used to measure your sharpness of vision at multiple distances.

Arranged as a pyramid of sorts, the letters in the Snellen chart are specifically chosen and arranged to test your sharpness and clarity of vision at a baseline distance of 20 feet. During a visual acuity test, the Snellen eye chart is viewed as a projection, or mounted on a wall. Handheld versions of Snellen charts are used for testing near vision as well.

By viewing or reading each line from top to bottom (with one eye covered at a time), your eye doctor can gain a general approximation of the quality of your visual acuity, or sharpness. Where a line of characters begin to become difficult to see is the approximate measurement of your vision. The Snellen chart serves as a beginning—not an end—to a comprehensive eye examination.

What does “20/20” vision mean?

Snellen charts help to determine a baseline for your vision in each eye—a baseline typically measured against “20/20” vision. This means when you are 20 feet away from an object, you can comfortably see details that most people with normal vision can also see at 20 feet distance.

If you have 20/30 vision, that means what you see comfortably at 20 feet, can be seen by a person with “normal” vision at 30 feet. Your vision is weaker, in other words.

Conversely? In the rare instances where vision may test better than normal on a Snellen chart, a value of 20/10 vision means that you can see clearly from a distance of 20 feet, what a person with normal vision sees well at a distance of 10 feet. Make sense?

In fact, if you look closely at a Snellen eye chart, you’ll see the vision values associated with measuring your vision on the right or left side of each line of characters.

Vision screening

What’s the difference between a vision test and a vision screening? If you consider the vision test as the “goal” of having a comprehensive eye exam at regular intervals throughout your life, then a vision screening is one way to reach that goal. Vision screening sometimes determines an immediate need for vision testing.

It’s important to not confuse the two. A vision screening is not a substitute for a vision test or comprehensive eye exam performed by an eyecare professional. But it can play an important role in helping numerous groups get the vision testing they need.

What is vision screening?

A set of simple eye tests to help identify people who may have certain eye problems. Often performed by pediatricians, school nurses, assisted living caregivers and other healthcare professionals and volunteers, vision screening usually includes a vision test for your ability to see clearly at distances using the “Big E” chart (Snellen chart).

A vision screening may also include testing of your eye’s reaction to light, muscle coordination, or by viewing simple images and graphs that could reveal colorblindness or other hidden problems. The vision test you take to get your driver’s license is an example of a vision screening.

Community health organizations, public schools, wellness clinics, and assisted living facilities often offer vision screening as part of their services. Given at important intervals in life, such as early childhood, pre-teen years, and as you age, vision screening can help monitor the quality of your vision, and possibly identify common vision problems. But they’re not a substitute for a complete vision test given by an eyecare professional.

What is vision testing?

A comprehensive set of eye tests performed by an eyecare professional in a controlled office setting with equipment that goes far beyond what’s available at a vision screening.

Often performed with eyedrops that help the pupil “open up” (dilation), vision tests commonly include testing of vision at multiple distances, peripheral vision testing, and a series of procedures designed to check the structures of the eye for evidence of eye disease or eye problems like age-related macular degeneration, glaucoma, cataracts or diabetes.

A vision test from a qualified eyecare professional is important because many of the things hidden or unknowable at a vision screening, reveal themselves under closer professional observation.

And just as importantly, only an eyecare professional can direct you to the treatment necessary to improve your vision or protect your eyes—a prescription for corrective lenses, medications to treat common eye problems, or a wide variety of surgical options now available to people with eye problems.

How often should you have a vision test?

As a general rule of thumb, it’s a good idea to have a comprehensive eye exam and vision test at least every two years. This especially includes children below the age of 5, who may not fully understand that they’re even having a vision problem until they undergo a professional vision test.

Vision can change rapidly throughout childhood. Regular vision testing is a quick and smart way to keep up with those changes.

In many instances, more frequent vision testing is recommended. If you have diabetes, for example, you are at higher risk for developing glaucoma, cataracts and diabetic retinopathy–damage to the blood vessels in the retina. After age 35, the risks increase for a host of age-related eye problems or diseases such as presbyopia, macular degeneration, and cataracts.

A comprehensive eye exam every year is not unheard of. Vision tests are convenient and protect your eyes in the short term, and long term.

Vision testing

Vision testing at the eye doctor is as individual as you are. When it comes to vision testing, no two eye exams are alike, because no two people are alike. In fact, it’s those differences that often determine what types of vision testing—and vision testing equipment—are used during any given examination.

Types of vision testing

  • Visual acuity testing: The Snellen Chart (the chart with the big E at the top) is used to test each eye for visual acuity or “sharpness” at a distance. A smaller, hand-held chart is used to test near vision.
  • Visual field testing: Manual and automatic testing designed to measure the quality of your side vision (peripheral vision). This type of test usually involves covering one eye and focusing the other on a fixed point in front of you, while describing what you can see on the “periphery” of your vision.
  • Cover testing: By having you focus on a distant object within a room, and then alternately covering each eye, your eyecare professional can see if your eyes work together, or must refocus slightly.
  • Color-blind testing: Using a series of multi-colored dots arranged within a circle, color-blind vision testing “hides” numbers within the overall pattern of dots. These numbers will appear as easy-to-see colored numbers to everyone except those few people who suffer from various degrees of color-blindness—the inability to perceive certain colors or color combinations.
  • Refraction testing: Refraction errors like nearsightedness and farsightedness are the most common eye problems. Vision testing is used to determine how strong your prescription glasses must be to see clearly, based on how your eyes react while using the vision testing equipment.

Phoropters are machines that allow your eye doctor to “switch” lenses during your exam to see if your focus is better, or worse. Autorefractors are machines that automatically check the lens power needed to clearly focus images on your retina for the best possible vision.

  • Slit lamp testing: This piece of vision testing equipment combines a simple chin rest with a light source that produces a “slit” of light that’s used scan your eye. Your eye doctor (with the help of special viewing lenses) can look into the internal structure of your eye to potentially diagnose a host of eye problems and diseases.
  • Tonometry (Glaucoma) Testing: There are two types of glaucoma vision testing, each with the goal of measuring the internal pressure of the eye. Increased eye pressure is a warning sign for glaucoma, a series of eye diseases that damages the optic nerve of the eye, limiting and sometimes eliminating vision.
  • The “Puffer” Test: A light is beamed into your eye while a gentle puff of air is blown across the eye’s surface. A special machine measures the resistance of the eye to the puff of air, and then calculates internal eye pressure.
  • The Touch Test: Using a machine called an applanation tonometer, a special probe makes gentle contact with the eye’s surface to measure internal eye pressure. Your eye doctor may numb your eye in advance.
  • Dilation testing: Sometimes, your eye doctor will use special drops to “open up” your pupil (dilate it) so that as much light as possible can enter the eye. Using special magnifying lenses and other vision testing equipment, your eye doctor can diagnose a host of eye problems and see internal structures that indicate the presence of eye diseases.

Vision testing is both thorough and painless, though there may be some discomfort from direct beams of light momentarily. In addition, the drops used to dilate pupils may take a little time to wear off, so you will be sensitive to bright light, and may need assistance driving after vision testing that includes pupil dilation.

+ Medications
a man with eyeglasses

/ EYE DOCTOR

Medications

In addition to being “windows to the soul”, your eyes are also a clear indicator—or window—to your overall general health. That’s why it’s so important to understand the relationship between your eyes and any medications you may currently be using.

Since eye doctors can use your eye health as a predictor or measure of your general health, all medications that could affect your eyes need to be discussed with your eye care professional.

Can non eye-related medications affect my eyesight?

Yes, they can. Because of its rich blood supply and relatively small mass, the eye is susceptible to certain drugs and toxic agents. Many medications, both prescription and nonprescription (over the counter) can alter the quantity or the quality of your vision, or pose a threat to your future eye health.

Your current medications and healthy sight actually go hand in hand, and need to be discussed with your eye doctor.

How can medications affect eyesight?

Potential adverse effects of medications on your eyes can be classified into three basic categories:

  1. Medications that can cause blurred vision or alter your eyes’ ability to adjust to the environment can affect your quantity of vision.
  2. Medications that can induce glare, increase light sensitivity, or impair light-dark adaptation affect your quality of vision.
  3. Medications that can contribute to the development of ocular disorders. Certain medications can become a factor in developing disorders such as: cataracts, keratopathies, retinopathies, maculopathies, optic neuropathies, and glaucoma. These potential effects of certain medications are typically long term, potentially more serious, and pose a greater threat to vision. However, their progression can usually be prevented (or limited) if recognized early and the offending agent is discontinued or the dosage reduced.

Are there other factors to consider connecting medications and eyesight?

There is a growing body of experimental and epidemiological evidence connecting chronic UVR exposure with vision-threatening ocular disorders such as cataracts. Medications that either dilate the pupil (increasing the amount of UV entering the eye) or increase the effects of UV on the eye (photosensitizers) may increase the risk of developing UV-related eye disease.

If you are concerned about the effects your medications may have on your eyes, or experience any eye-related side effects, you should consult your primary care doctor or eye care professional.