Please use the following information to learn more about common health problems, and musculoskeletal conditions and the amazing treatments modern optometrists can offer. If you have any questions, please consider one of "America's Best Optometrists" for a consultation, examination and care.

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What is an Optometrist?

What is an Optometrist?

Doctors of Optometry treat, and manage disorders, diseases and injuries to the visual system. They diagnose ailments of the eye, its associated structures, and general systemic conditions that may affect the eye. Optometrists prescribe medications, perform vision therapy and rehabilitation, prescribe glasses and contact lenses, and perform specific surgical procedures. They are experts in counseling patients regarding non-surgical and surgical alternatives to treat sight and vision problems.

Optometrists are highly trained professionals who have completed four years of college, followed by an additional four years of education at professional school of Optometry. Optometrists may continue to complete residency training in a specialty area of practice.

Amblyopia (Lazy Eye)

Amblyopia (Lazy Eye)

Amblyopia, often called “lazy eye” occurs when the central vision in one eye diminishes or does not develop as it should; so that the brain fails to recognize the image transmitted by the affected eye. Peripheral vision is not impacted, and the amblyopic eye is not considered void of sight. However, vision in the affected eye tends to worsen over time. Amblyopia cannot be corrected solely with glasses or contact lenses. The condition affects keen depth perception and limits an individual’s ability to participate in activities that require such perception.

Causes of Amblyopia

Amblyopia is typically seen in children under 8 years of age and may impact up to 4% of children. It is rare for an adult to develop amblyopia. The primary cause of this condition is inadequate development of vision. Low birth weight and premature birth are risk factors, as well. Amblyopia can also result or be associated with:

  • Cataracts or another eye impediment
  • Eyes that are crossed
  • Both eyes not being used together
  • Having a great degree of farsightedness in one eye and a great degree of nearsightedness in the other

Amblyopia Symptoms

Typically, few symptoms are present with amblyopia, and the symptoms may not be easily noticed. A child may tend to look at things with one eye versus the other or bump into things on the side with the affected vision.

Diagnosing & Treating Amblyopia

A thorough examination by an optometrist is needed to diagnose amblyopia. Most children are unaware they suffer from this condition. Therefore, children should attend eye exams at six months of age and three years of age in accordance with guidelines established by the American Optometric Association. Another check prior to a child entering school is recommended, as well.

Amblyopia will not resolve without treatment and will in fact worsen. The possibility of total recovery increases with early diagnosis and treatment. Intervention in pre-teen to adult years yields less beneficial results. Amblyopia treatment may include:

  • Prescription glasses
  • Vision therapy that helps both eyes work in tandem
  • Prisms
  • Wearing an eye patch on the unaffected eye some or all of the time
  • A combination of these treatments

Anterior Uveitis

Anterior Uveitis

The condition called anterior uveitis occurs when the eye’s middle layer, containing the iris and the ciliary body, becomes inflamed. Swelling of the retina, cataract formation, or glaucoma can result and cause significant damage to the vision, including vision loss.


Generally, an underlying cause of anterior uveitis cannot be found. However, the following conditions may contribute to anterior uveitis:

  • Complications of another disease
  • Eye trauma
  • Health conditions such as mumps, rubella, and rheumatoid arthritis


  • A small pupil
  • An eye that is sore, inflamed, and appears red
  • Blurred vision
  • Light sensitivity

Anterior uveitis symptoms can mimic those of other eye condition, so it is important to see an optometrist for a thorough exam and diagnosis.


Treatment for anterior uveitis can consist of anti-inflammatory medication coupled with prescription eye drops for several days to many weeks.



Astigmatism is a condition when vision is blurred because of an abnormally shaped cornea or lens. The result is that light cannot focus correctly on the retina, causing fuzzy near and far vision. Astigmatism is a common condition that is often seen in tandem with nearsightedness or farsightedness. Because these conditions impact an eye’s ability to refract (bend) light, they are called refractive errors.

No treatment is needed for small degrees of astigmatism, as vision may not be significantly impacted. Higher degrees of astigmatism usually require care, to renew visual acuity or to alleviate headaches or eye discomfort that may occur.

Causes of Astigmatism

Typically, astigmatism is inherited or exists at birth. It can increase or decrease as time passes. Other factors that influence astigmatism include eye surgery, eye injury, and an uncommon corneal condition called keratoconus.

Diagnosing & Treating Astigmatism

A thorough vision test allows an optometrist to determine a diagnosis of astigmatism. Components of the exam may include:

  • A test of visual acuity (accuracy)
  • A measurement of refraction
  • Keratometry, which measure the cornea curvature
  • Corneal topography, which is an assessment of the shape of the cornea

Treatment for astigmatism may include:

  • Eyeglasses
  • Contacts
  • Laser eye surgery (photorefractive keratectomy [PRK], laser in situ keratomileusis [LASIK])
  • Non-invasive corneal modification, called orthokeratology (ortho-k)



Blepharitis is an inflammation of the eyelids causing red, irritated, itchy eyelids and the formation of dandruff-like scales on eyelashes. It is a common eye disorder caused by either bacteria or a skin condition such as dandruff of the scalp or acne rosacea. Blepharitis affects people of all ages. Although uncomfortable, it is not contagious and generally does not cause any permanent damage to eyesight.

There are two classifications of blepharitis:

  • Anterior blepharitis: Impacts the outside of the front edge of the lid, near the lashes.
  • Posterior blepharitis: Impacts the inner edge of the lid, near the eyeball.

The types of blepharitis included in these classifications are:

  • Meibomian blepharitis: The lining of the eyelids may appear red, oil glands are blocked, and tears may be of diminished quality. This type of blepharitis is associated with posterior blepharitis.
  • Seborrheic blepharitis: Eyelids may appear red, and greasy flakes are present at the eyelash base.
  • Staphyloccal blepharitis: Eyelids may stick together and appear thick. Eyelashes may be missing or pointing in different directions.
  • Ulcerative blepharitis: Matting appears around eyelids, leaving sores when removed. Eyelash loss may also occur, as well as ongoing tearing and eyelids that appear distorted along the edges. The cornea may become swollen in severe cases.


Factors that may contribute to the development of blepharitis include:

  • Acne rosacea
  • Allergies
  • Bacterial growth
  • Dandruff on the scalp and eyebrows
  • Erratic oil production in the eyelid glands
  • Eyelash infestation


Blepharitis symptoms can be mild, or they can become severe and impact vision, cause gaps in the lash line, and create corneal swelling. Other symptoms include:

  • A burning sensation in the eye
  • Abnormal tearing
  • Crusting along the eyelids
  • Dry eyes
  • Eyes that are swollen and red
  • The feeling of grit in the eye
  • Itchiness


The type of treatment recommended for blepharitis depends on the type. Often, regular cleaning of the eyelids and washing of the scalp and face can keep the condition in check. Once blepharitis occurs, it usually does not resolve completely and can recur following treatment. Treatment can include:

  • Anti-dandruff shampoo
  • Artificial tears
  • Eliminating eye makeup and discontinuing wearing contact lenses while blepharitis is present
  • Eyelid massage
  • Eyelid scrubs
  • Lubricating ointments
  • Medications, including antibiotics
  • Warm compresses



The lens sits behind the iris of the eye and focuses light on the retina. A cataract forms when the proteins and water that make up the lens change and cause clouding. Cataracts can impede vision – depending on where they are located and how big they are – by inhibiting the ability of the lens to properly focus light on the retina. Generally, cataracts form very slowly and affect both eyes, with one eye sometimes experiencing more negative symptoms of cataract than the other.

Cataracts typically impact people 55 years of age and older; however, young children and even infants can develop cataracts.

Types of Cataracts

Cataracts can form in the outer, middle, or inner layers of the lens. The location of the cataract determines its type.

  • Posterior capsular cataracts form in the outer layer and typically develop quickly.
  • Cortical cataracts form in the middle layer of the lens and are wedge or spoke-shaped.
  • Nuclear cataracts form in the innermost layers of the lens and may cause the nucleus of the lens to become yellow or brown.

Cataract Symptoms

  • Vision that is blurred or appears hazy
  • Refractive changes
  • Dimming of the appearance of colors
  • Increased difficulty dealing with glare, especially during night driving
  • Diminished ability to see at night

Factors that May Contribute to Cataract Formation

  • Age
  • Alcohol consumption
  • Diabetes mellitus
  • Eye injury or eye surgery
  • Low levels of antioxidants in the diet
  • Unprotected exposure to UV light
  • Smoking

A mother who develops an infection, such as rubella, during pregnancy can have a baby born with cataracts. Cataracts may also be inherited.

Diagnosing & Treating Cataracts

A comprehensive eye exam is conducted to determine a diagnosis of cataracts. Aspects of the exam typically include:

  • A discussion of current vision difficulties and health history
  • Refraction
  • Measurement of visual acuity
  • Use of magnification to assess the condition of the lens and identify cataracts
  • Eye pressure measurement
  • Eye dilation to assess the condition of the retina
  • Glare sensitivity testing
  • Color vision testing
  • Other testing, as needed, to determine if a condition other than cataracts is affecting vision

Treatment for cataracts includes:

  • No treatment (if vision is not impacted or is only slight affected) followed by careful monitoring and regular exams
  • Increased light when reading
  • Eyeglass prescription change
  • Anti-glare coating on eyeglass lenses
  • Surgery

Cataract Surgery

Surgery may be performed to address cataracts that significantly impact vision and prevent a person from pursuing a normal routine. During cataract surgery, the lens of the eye is removed and an artificial lens put in its place. This new lens can replicate the focusing ability of a healthy eye. Considered one of the safest surgeries performed in the US, cataract surgery can be extremely effective, with 90% of recipients reporting improved vision. If a new lens cannot be placed in the eye, eyeglasses or contact lenses may remedy vision difficulties.

Types of cataract surgery include:

  • Extracapsular surgery, in which a large incision is made in the cornea to remove the lens core wholly.
  • Small incision cataract surgery, in which a tiny probe is inserted in the eye through a small incision on the side of the cornea in order to project ultrasound waves that fragment the lens; these fragments are then suctioned out.

Risks of cataract surgery including bleeding, infection, and retinal detachment.

Preventing Cataracts

While it may not be completely possible to prevent cataracts, there are ways to reduce risk:

  • Stop smoking or reduce the number of cigarettes you smoke
  • Wear glasses that block UV light exposure
  • Increase consumption of foods and/or supplements containing vitamins C and E, lutein/zeaxanthin, and zinc



A chalazion typically starts out as a small swollen area on the upper eyelid. It may be red in color and feel sore. After a few days, a lump that may grow to pea-size may appear. Chalazions form when oil glands in the eyelid become blocked, fail to drain and form a lump. After some time  buildup may cause the gland to burst. Eye irritation can develop when oil is released.  

Chalazions usually impact adults in the 30-50 age range. A chalazion is often confused with a sty but chalazions can develop following sty formation. Most chalazia disappear without treatment in several weeks to a month. However, they often recur. Rarely, they may be an indication of an infection or skin cancer.


  • Small bump on the eyelid
  • Tearing eyes
  • Vision that is blurred

Risk Factors:

  • Acne rosacea
  • Chronic blepharitis
  • Seborrheic dermatitis
  • Tuberculosis
  • Viruses

Treating Chalazions:
Oftentimes, a chalazion will resolve without medical treatment. Warm compresses applied to the affected eye several times a day for 10 to 15 minutes may help by softening the oil in the blocked gland and encouraging drainage. Gentle massage of the eyelid may also be beneficial. Chalazions that do not resolve after a month need to be seen by an eye doctor.

Color Vision Deficiency

Color Vision Deficiency

Sometimes called color blindness, color vision deficiency occurs when a person cannot tell the difference between certain colors; the most common being inability to discern shades of red and green. Blue and yellow deficiency is a less common form. In severe cases, affected individuals  cannot see any colors, only black and white or different shades of gray. This is called achromatopsia.

Color vision deficiency occurs when the cones found in the retina of each eye lack a pigment enabling them to see certain colors such as red, green, or blue. If the condition is inherited, both eyes are typically affected. If illness or injury results in color vision deficiency, then one eye may be impacted. Color vision deficiency is usually not a threat to vision.

Often, a person may not know that they have color vision deficiency, so children should receive a comprehensive eye exam performed by an optometrist prior to beginning school.

Types of Color Vision Deficiency

  • Red-green: A person with this color vision deficiency has a hard time determining gradations of red and green. It does not mean that they cannot see the colors.
  • Blue-yellow: People with this condition often have red-green color vision deficiency as well and typically see a gray or neutral shade in place of these colors.

Causes of Color Vision Deficiency
This condition can be caused by disease or injury to the retina or optic nerve. More commonly, though, it is inherited, typically passed from mother to son. Color vision deficiency affects approximately 8% of white males and is present at birth. Diseases that can result in color vision deficiency include:

  • Alcoholism
  • Alzheimer's disease
  • Diabetes
  • Glaucoma
  • Leukemia
  • Macular degeneration
  • Multiple sclerosis
  • Parkinson's disease
  • Sickle cell anemia

Other causes include aging, certain medications, and exposure to certain fertilizers and chemicals, such as styrene. To help “identify” colors, affected people may have someone help them organize or label objects such as clothing; or work to remember the order of colors, such as on a traffic light.

No treatment exists for color vision deficiency that is inherited, although specially tinted contacts or glasses may help. For color vision deficiency caused by disease or injury, certain treatments may result in color vision improvement.

Computer Vision Syndrome

Computer Vision Syndrome

Working at a computer for longs periods of time places a high level of demand on the eyes, making them work harder and causing a variety of eye symptoms, with longer periods of use making symptoms worse. Grouped together, these eye issues are called “Computer Vision Syndrome” (CVS). People with untreated vision problems – such as presbyopia, farsightedness, problems with eye coordination, and other issues – run a higher risk of developing CVS.

Symptoms of CVS

  • Vision that appears blurred
  • Discomfort in the neck and shoulder regions
  • Dry or strained eyes
  • Headaches

Factors that contribute to these symptoms include computer screen glare, improper lighting, not sitting an appropriate distance from a computer, and poor posture when occupied on the computer. Working at a computer for two hours or more at a time increases the risk of CVS.

The good news is that many CVS symptoms go away when a person is not on a computer. However, some symptoms may linger, or worsen if not properly addressed.

Diagnosing & Treating CVS
An optometrist will conduct a thorough eye exam to determine a diagnosis of CVS. During the exam, the doctor may ask about health history, current symptoms, your home or work environment, and medication use. Other elements of the exam may include:

  • A test of visual acuity
  • Assessment of eye movement and focus
  • Refraction

Treatment may consist of:

  • Recommending more regular vision checkups
  • Prescription glasses or contact lenses specially made for computer use
  • Vision therapy to improve eye coordination and focus
  • Changing the positioning of your chair and/or computer to control distance, glare, and lighting issues

Changes Regarding Computer Use

  • Properly locate the computer screen 4-5 inches below the level of the eyes.
  • Sit in a comfortable, well-padded chair so that your feet rest easily on the floor and your wrists do not rest on the keyboard.
  • Minimize computer screen glare by adjusting the lighting in the room or using a screen on your computer.
  • Place needed materials (papers, books, etc.) so that they can be viewed without moving the head.
  • Keep eyes moist by blinking regularly.
  • Factor in breaks to ease strain: (Look into the distance for 20 seconds every 20 minutes when on the computer. Take a 15-minute break every 2 hours.



The tissue that lines the inner surface of the eyelid is called the conjunctiva. Conjunctivitis occurs when this layer of tissue becomes infected or inflamed. Commonly known as “pink eye,” conjunctivitis is typically considered a minor infection of the eye. However, it can turn serious. Conjunctivitis occurs commonly in the population, especially among children. Some types of conjunctivitis can spread rapidly to others.

Symptoms of Conjunctivitis
The following symptoms may occur in one or both eyes:

  • The white of the eye appears pink
  • A feeling of sand or another gritty material in the eye
  • Eyes that tear more than normal
  • Discharge from the eye
  • Burning or itching
  • Lids that swell
  • Sensitivity to light

Types & Causes of Conjunctivitis

  • Allergic conjunctivitis is, as the name implies, triggered by allergies, especially in people who suffer from season allergies. This type of conjunctivitis typically affects both eyes.
  • Bacterial conjunctivitis is typically caused by streptococcal or staphylococcal bacteria, usually from a person’s own body. Other causes of bacterial conjunctivitis include bacteria transmitted by touching other people, bacteria carried by insects, not washing hands before touching the eyes, and bacteria in cosmetics. 
  • Chemical conjunctivitis results from exposure to chemicals, such as those used in pools, toxic chemicals, and air pollution.
  • Giant papillary conjunctivitis occurs when a foreign body is present in the eye for long periods of time, such as a soft contact lens worn for multiple days or weeks, a hard contact lens, or a prosthetic eye.
  • Ophthalmia neonatorum affects newborns and is caused by exposure to gonorrhea or Chlamydia during the birthing process. This type of conjunctivitis can cause permanent damage to the eyes if treatment is not rendered immediately following birth.
  • Viral conjunctivitis usually stems from exposure to contagious viruses linked to the common cold – either by another person sneezing or coughing or by the virus spreading through the mucous membranes of the body.

Diagnosing & Treating Conjunctivitis
Diagnosing conjunctivitis may consist of:

  • A discussion of symptoms, as well as environmental or health conditions that may play a role in conjunctivitis
  • A thorough exam of external and inner eye structures
  • Examination with magnification and bright light
  • A test of visual acuity
  • A conjuctival tissue culture or smear

The goals of treating conjunctivitis are to lessen discomfort, prevent the spread of conjunctivitis, and reduce the amount of time the eye is impacted. Treatment may include:

  • Allergic conjunctivitis can be addressed by determining and eliminating the source of irritation. Treating the area with cool compresses, artificial tears, antihistamines, non-steroidal anti-inflammatory medicines, or prescription eye drops can alleviate symptoms.
  • Bacterial conjunctivitis is typically remedied with prescription ointments or eye drops.
  • Chemical conjunctivitis mandates using saline solution to flush the eye, following by the use of topical steroids. This type of conjunctivitis can be deemed a medical emergency, especially if it is caused by a chemical that can burn, scar the eye, or cause loss of vision.
  • Viral conjunctivitis must run its course, as there are no medications that cure viruses. Artificial tears, cool compresses, and steroid eye drops may help relieve symptoms.

If you wear contact lenses, you may need to stop wearing them until your conjunctivitis goes away. Conjunctivitis caused by contact lens wear may require using a new brand of solution to disinfect lenses or wearing a different type of lens that requires more frequent cleaning or disposal.

If you have been diagnosed with conjunctivitis:

  • Wash hands often and thoroughly
  • Avoid touching or rubbing your eyes
  • Use a new towel each day
  • Don’t share towels with others
  • Wear contact lenses for the length of time recommended by your doctor
  • Don’t wear eye makeup while you have conjunctivitis
  • Throw away old eye cosmetics
  • Never use someone else’s makeup or eye care items

Diabetic Retinopathy

Diabetic Retinopathy

Diabetes can negatively impact the retina’s circulatory system. Diabetic retinopathy occurs when blood vessels in the retina leak causing swelling in the eye and cloudy vision. The risk of developing diabetic retinopathy increases with the length of time a person suffers from diabetes. Diabetic retinopathy typically impacts both eyes and can result in blindness, if not addressed.

Types of Diabetic Retinopathy

  • Non-proliferative diabetic retinopathy (NPDR): This is early-stage diabetic retinopathy in which weakened blood vessels develop bulges called micro-aneurysms. Fluid from these micro-aneurysms can leak into the retina and cause macular swelling.
  • Proliferative diabetic retinopathy (PDR):  This is a more advanced stage of diabetic retinopathy in which problems with circulation deprive the retina of oxygen. This causes new blood vessels to form that can leak into the vitreous of the eye. Clouded vision, along with retinal detachment and glaucoma can occur. Untreated PDR can result in significant loss of vision or blindness.


  • Blurry vision
  • Central vision that seems to have an empty or dark spot
  • Poor night vision
  • The formation of floaters or spots when looking at objects

Who is at Risk:

  • People with high blood pressure and cholesterol levels
  • Women who are pregnant
  • People with Type 1 or Type 2 diabetes
  • Prevalence is higher in African Americans and Hispanics

Treating Diabetic Retinopathy
The specific treatment for an individual with diabetic retinopathy depends on the progression of the condition. Treatments include:

  • Monitoring and control of blood sugar levels
  • Laser surgery
  • Injectable medicines that inhibit blood vessel formation or lessen swelling
  • Surgical removal and replacement of the vitreous
  • Surgery to repair retinal detachment
  • Special lenses and devices to accentuate remaining vision

If you have diabetes, the American Optometric Association recommends a yearly comprehensive exam that includes eye dilation to detect diabetic retinopathy. When identified and treated in the early stage, significant loss of vision can be deterred.

Additionally, people with diabetes should:

  • Avoid alcohol
  • Exercise on a regular basis
  • Keep blood pressure under control
  • Stop smoking
  • Maintain a healthy diet
  • Take their medication

Dry Eye

Dry Eye

The condition known as dry eye is a common condition that may become a chronic one in people over the age of 65. It occurs when a person does not produce enough tears for nourishment and lubrication of the eye. Poor quality tears can also contribute to the condition of dry eye. Tears help keep eyes healthy and aid in vision by keeping the cornea smooth and moist, eliminating external matter that may get in the eye, and decreasing infection risk. Tears that are not used simply drain into small ducts in the corner of the eye.

Causes of Dry Eye

  • Keratoconjunctivitis sicca (KCS), also called dry eye syndrome, in which tears do not contain sufficient water
  • Inadequate tear production
  • Certain eye conditions
  • Hormonal changes
  • Diminishment of tear production due to age, specific medications, or certain medical issues
  • Smoke exposure
  • A dry, windy climate that causes tears to quickly evaporate
  • Excess time between blinks, such as when working at a computer
  • Long-term contact lens wear
  • Eye surgery

Symptoms of Dry Eye

  • Excessive watering of the eye
  • Eyes that burn, itch, or feel gritty
  • Vision that appears blurred
  • Vision and eye damage in extreme cases

Diagnosing & Treating Dry Eye
Diagnosis typically entails a thorough examination of the eyes, a discussion of healthy history and current medication use, testing tear quality and quantity, consideration of potential environmental causes, and other measures which may include:

  • Examination of the structure of the eyelid
  • The use of magnification and bright light to evaluate the condition of the eye
  • Assessment of the way you blink
  • Instilling dye to evaluate tear function

Treatment for dry eye may include:

  • The use of artificial tears
  • Eyedrops and supplements to improve the production of tears
  • Eyedrops to decrease inflammation
  • Blocking the tear ducts to conserve tears 

Caring for Dry Eye at Home

  • Increase humidity levels in home and work environments
  • Blink regularly
  • Supplement your diet with essential fatty acids
  • Use sunglasses when outside
Drink 8 to 10 glasses of water per day



A person who is farsighted cannot clearly focus on close objects but can see distant objects clearly. Hyperopia, which is the medical term for this condition, occurs when light is not focused properly as it enters the eye, either as a result of a cornea that is not curved enough or an eye that is too short from front to back.

Hyperopia is a common, typically naturally occurring condition. It is only deemed a problem when it severely impacts vision. Reports show that more than 50% of glasses wearers do so to correct farsightedness.

Signs of Farsightedness

  • Trouble seeing close objects clearly
  • Headaches
  • Eye strain
  • Eye tiredness
  • Eyes that burn or ache
  • Tenseness or a nervous feeling after periods of concentration
  • Blurred vision

Causes of Farsightedness

  • An eyeball that does not have the proper distance from front to back
  • Not enough cornea curvature
  • Heredity
  • Environmental reasons

Diagnosing & Treating Farsightedness
An exam by an optometrist or a vision screening can provide information to diagnose farsightedness.

Minimal farsightedness may not require treatment. Prescription glasses or contacts can correct farsightedness for many people.



Spots that appear to drift across the eye are called floaters. These specks reside in the vitreous fluid inside the eye. Floaters can appear as thin strands, dots, or web-like structures. If you attempt to focus your vision on a floater, it appears to move. This is because the floaters exist within the eye itself.

Causes of Floaters
Floaters can be caused by specks of protein or another biological substance formed in the eye prior to birth or from aging, eye injury, or disease in the eye. In the cases of injury, disease, and aging, the vitreous in the eye can break down and cause bits of vitreous material to appear as floaters.

Generally, the spots known as floaters are not indicative of vision damage, and they don’t harm vision. However, if you experience an increase in floaters or a change in the appearance of floaters, it is advised that you see an optometrist to rule out a more serious eye condition.

Diagnosing & Treating Floaters
An eye examination by an optometrist can diagnose floaters. This condition typically requires no treatment.



Glaucoma is actually the name for a group of eye issues. It occurs when pressure builds up in the eye as a result of an inadequate drainage angle in the eye, although the exact cause of glaucoma is unknown. Glaucoma typically impacts people age 40 and over (although there is an infantile form of glaucoma) and is the second leading cause of blindness in the United States. It is the primary cause of blindness among Hispanics. Glaucoma causes degenerative optic nerve damage. Because the optic nerve is responsible for sending signals to the brain from the eye, damage to the nerve from glaucoma ultimately causes vision loss.

It is important to note that not all pressure changes in the eye cause glaucoma and that some people with normal eye pressure will be diagnosed with the condition. Glaucoma will occur when eye pressure increases beyond the degree a person’s optic nerve can withstand.

Glaucoma Risk Factors

  • Being over the age of 60 or an African American over the age of 40
  • Being of African American, Hispanic, Asian (for angle-closure glaucoma) or Japanese (for low-tension glaucoma) descent
  • Having certain medical conditions, such as high blood pressure, heart disease, or diabetes
  • Having glaucoma in your family history
  • Sustaining an eye injury
  • Having an unusually sensitive optic nerve
  • Having one or more of the following eye conditions: thin cornea, eye tumors, retinal detachment, eye swelling, excessive nearsightedness
  • Experiencing diminished blood flow to the optic nerve, such as caused by atherosclerosis

Types of Glaucoma

  • Primary open-angle glaucoma is the most common form. It typically starts slowly, generally first impacting peripheral vision and then progressing to diminish central vision. Because it may not present symptoms at the onset, sufferers may be unaware that they have it until they experience major vision loss. Diminishment of vision in both eyes and, potentially, blindness may occur if this type of glaucoma is not treated.
  • Acute angle closure glaucoma is a less common form of the disease. Caused by an increase in the pressure in the eye that usually occurs rapidly, acute angle closure glaucoma must be treated as a medical emergency to prevent vision loss. Symptoms include eye redness, significant eye pain, upset stomach, vision that appears blurred, and the appearance of colored rings forming around lights.
  • Angle-closure glaucoma may occur as an acute or chronic condition. It develops acutely when aqueous fluid drainage is completely blocked, causing an increase in eye pressure.
  • Normal-tension glaucoma occurs when the optic nerve sustains damage even though eye pressure never extends beyond the normal range.
  • Secondary glaucoma is generally caused by an eye disease, eye injury, certain medications, an abnormality in the formation of the eye, or – less commonly – eye surgery.

Diagnosing & Treating Glaucoma
A thorough eye exam is needed to diagnose glaucoma. The doctor will look for alterations in the optic nerve, nerve tissue loss, and vision loss over a period of time.

Testing for glaucoma may include:

  • A patient health history
  • Measurement of eye pressure, called tonometry; or serial tonometry, which requires frequent pressure testing
  • Examination of the retina
  • Testing of visual acuity
  • Measurement of the thickness of the cornea, called pachymetry 
  • Perimetry, or visual field testing
  • Eye angle anatomy assessment, called gonioscopy

Glaucoma can be controlled and the risk of vision loss lessened by medication and other treatments; however, it cannot be prevented or cured. Annual eye dilation is recommended by the American Optometric Association to screen for glaucoma.

Glaucoma treatment may include:

  • Medications to lessen eye pressure
  • Laser surgery
  • Conventional surgery 
  • Drainage valve implants

Treatment for acute angle-closure glaucoma is considered an emergency and may consist of numerous medications along with laser surgery to relieve pressure.

Glaucoma Outlook
Because there is no cure for glaucoma, treatment must continue for the remainder of a patient’s life. The degenerative affects of the disease may be halted or slowed through continued treatment and constant monitoring of eye pressure by a doctor.



The vision disorder known as keratoconus typically affects people who are in their late teens to early 20s. It is caused when the cornea thins and becomes cone shaped, distorting vision because light no longer focuses correctly on the cornea. The progression of keratoconus may last for up to 20 years and then slow. A person with keratoconus may experience different gradations of the condition in each eye.  Early-stage symptoms include:

  • Light and glare sensitivity
  • Blurred vision
  • Distortion of objects

As the condition progresses, the cornea may bulge, which causes a decrease in vision. Rarely, corneal swelling can contribute to a dramatic decrease in vision. This is caused by a crack forming in the cornea due to the strain of swelling. Ultimately, the crack, which may last for months, is replaced with scar tissue. Eye drops can be used if this occurs, but they will only provide relief from symptoms and will not halt the progression of keratoconus. Additional treatments for keratoconus include:

  • Prescription glass or soft contact lenses to addresses changes in vision due to astigmatism and nearsightedness
  • Rigid gas permeable contact lenses to correct more severe vision decreases
  • Corneal transplant to address severe keratoconus

Macular Degeneration

Macular Degeneration

Macular Degeneration, also called Age-Related Macular Degeneration (AMD), describes a condition in which the macula of the eye changes and causes loss of central vision. The macula resides in the inside back layer of the eye and is part of the retina. AMD typically impacts adults over the age of 50 and is this age group’s leading cause of significant vision loss. There are two types of AMD: wet and dry.

AMD tends to strike women earlier than it does men, and the Caucasian race suffers from AMD at a greater rate than other races. Reports from the Centers for Disease Control and Prevention state that almost 2 million people suffer from AMD. An estimated 7.3 million people run the risk of incurring major loss of vision due to AMD.

Types of AMD

  • Dry (atrophic) macular degeneration: In this most common form of the condition, macular tissue thins and, eventually, ceases to function.
  • Wet (exudative) macular degeneration: This lesson common form of the condition can cause rapid vision loss when blood vessels that form under the macula leak, impacting the central vision.

AMD Symptoms

  • A lack of vision or a dark shape in the central vision
  • Slow loss of visual acuity
  • Diminishment of color vision
  • The shape of things appears distorted

Diagnosis & Treating AMD
At the onset, AMD may not present symptoms. However, if any symptoms are experienced, it is important to see an optometrist for an eye exam and test to determine a diagnosis. Vision lost to AMD cannot be restored, but an optometrist can help to make the most of remaining vision.

  • No cure exists for dry AMD, although changes to the diet may decrease the progression of the condition. It is currently thought that consuming dark green leafy vegetables and foods low in fat, along with nutritional supplements, may help.
  • There is also no cure for wet AMD. Early detection, however, coupled with laser therapy to seal blood vessels leaking into the macula, Photodynamic Therapy (PDT) that utilizes medicine placed directly into the bloodstream and activated with a laser, or a new therapy involving an ingestible medication in the back of the eye may slow vision loss.

Lessen the Risk of AMD

To lessen the risk of AMD and other eyes diseases, it may be beneficial to consume foods high in zinc, lutein/zeaxanthin, and vitamins E and C.



The medical term for nearsightedness is myopia. This common eye condition causes difficulty clearly focusing on objects at a distance. It occurs as a result of excess cornea curvature or an eye that is too long from front to back. This causes images entering the eye to focus incorrectly and appear blurry.

Estimates show that approximately 30% of people in the US are nearsightedness. This condition is typically first noted in children of school age (although it can develop in adulthood) and continues worsening until approximately age 20. The first sign of nearsightedness in children is often trouble seeing in the classroom.

Night myopia causes blurred vision during nighttime. Pseudo myopia occurs after long periods of activity that require close focus with the eyes. Pseudo myopia is not permanent, but may cause vision diminishment over time.

Causes of Nearsightedness

  • Hereditary
  • Diabetes
  • Visual stress caused by working at a computer, reading, or other close work
  • Early-stage cataract
  • Environmental factors

Diagnosing & Treating Nearsightedness
A thorough eye exam conducted by an optometrist can determine a diagnosis of nearsightedness. The exam may include:

  • Testing visual acuity
  • Use of a phoropter and retinoscope to determine how the eyes focus light

Treatment for nearsightedness includes:

  • Eyeglasses or contact lenses worn all the time or only at certain times
  • Laser in situ keratomileusis (LASIK)
  • Lens implants
  • Orthokeratology (ortho-k)
  • Photorefractive keratectomy (PRK)
  • Vision therapy



Nystagmus is characterized by involuntary, repetitive eye movement – either in a circular motion, side to side, or up and down – that cause a person to be unable to focus steadily on an object. A person suffering my nystagmus may hold their head in an unusual position or nod their head to try to focus on an object. The condition can also cause decreased vision with regard to acuity and depth perception. Compromised depth perception may result in decreased coordination and balance skills.

Types of Nystagmus

  • Acquired: Can occur in late childhood through adulthood and can result from metabolic disorders, drug or alcohol toxicity, or central nervous system issues. Many times, however, the exact cause is not known.
  • Congenital: Typically develops when a child is approximately 2-3 months old and is characterized by eye movement that appears as a horizontal swinging motion. Congenital nystagmus is often seen in conjunction with albinism, underdevelopment of the optic nerve, congenital absence of the iris, and congenital cataract.
  • Spasmus nutans: Generally seen in children from 6 months of age to 3 years. It does not typically require treatment and may resolve on its own when a child is between 2-8 years old. Spasmus nutans nystagmus is characterized by head nodding and a head tilt with the eyes moving in any direction.

Nystagmus can also be distinguished by type of eye motion:

  • Jerk nystagmus: Eyes move slowly in one direction, then jerk back in the opposite direction.
  • Pendular nystagmus: Eyes move at the same speed in both directions.

While the exact cause of nystagmus is not known, nystagmus that develops in the early childhood years tends to be inherited and caused by an issue in the eye-to-brain pathway when no other medical problems are present. (Some types of nystagmus that occur in childhood can improve.) Nystagmus can occur in older individuals, as well, as a result of illness, injury, stroke, head injury, or multiple sclerosis. The condition may worsen from stress and fatigue. Usually, nystagmus accompanies an underlying medical issue or other eye problem.

Other causes include:

  • A high degree of nearsightedness or astigmatism
  • Albinism
  • Certain medications
  • Congenital cataracts
  • Diseases of the central nervous system
  • Inner ear swelling

Treating Nystagmus:
There is no cure for nystagmus. Treatments include:

  • Increased lighting
  • Instruction on how to position the head when looking at objects
  • Magnification, Large-print books
  • Prescription glasses and contact lenses to improve astigmatism, nearsightedness, or farsightedness
  • Prisms
  • Surgery
  • Treatment of underlying medical conditions

Ocular Hypertension

Ocular hypertension occurs when the pressure in the eyes increases beyond the normal range. This eye condition does not typically cause symptoms. However it can increase the risk of developing glaucoma, a damaging eye condition also characterized by elevated eye pressure. Therefore, patients with Ocular hypertension should receive regular eye exams to monitor the condition and lessen the risk of eye damage. No cure exists for ocular hypertension.

Who is at Risk?
Although ocular hypertension can impact all age ranges, the following groups are more frequently impacted by this condition:

  • Individuals with a family history of the ocular hypertension or glaucoma
  • Over 40 years of age especially African Americans
  • People with diabetes
  • Those who are extremely nearsighted



When the lens of the eye becomes inflexible, close objects become hard to see clearly. This condition is called presbyopia. It occurs as part of the aging process; therefore, it cannot be prevented. It may seem to sufferers of presbyopia that the change in vision occurs rapidly, usually after the age of 40. However, by the time diminishment of the ability to focus is noticed, the inflexibility of the lens has been occurring gradually over a period of years.

Symptoms of Presbyopia

  • Holding books and other items that require close focus away from your body in order to see them clearly
  • Headaches and eye fatigue following focused concentration on an activity
  • Inability to see text clearly at a distance at which words once were clear

Diagnosing & Treating Presbyopia
Visiting an optometrist for a thorough eye exam is the first step in diagnosing presbyopia.

Treatment for the condition may include:

  • Reading glasses
  • Prescription eyeglasses
  • Contact lenses

Presbyopia can occur in conjunction with astigmatism, nearsightedness, and farsightedness. Monitoring vision on a regular basis by attending checkups at an optometrist’s office can determine if changes in prescription or the type of eyewear used need to be made to accommodate vision changes.

Retinitis Pigmentosa

Retinitis Pigmentosa

An inherited eye disease, retinitis pigmentosa causes damage to the cones and rods in the retina. Cones contribute to central vision and ability to see colors. Rods are crucial to seeing at night and to peripheral vision. In retinitis pigmentosa, rods are impacted more than cones. While the progression of the disease is slow, ultimately loss of peripheral vision can occur. Many years may pass before the vision is significantly damaged.

Symptoms of this condition usually arise in childhood and the early teen years and include blindness at night, as well as a progressive loss of peripheral vision that results in tunnel vision.

Studies show that nutritional supplements containing lutein and vitamin A may slow the disease. Vision aids may also help compensate for the loss of side vision that occurs with this disease by maximizing existing vision.



The common term for strabismus is crossed eyes. This condition occurs when the eyes are not able to process or implement the directions sent by the brain telling them to work in tandem to focus on an object. One or both eyes can turn up, down, inward, or outward. Strabismus can occur as a constant condition, or it may occur occasionally as a result of fatigue, illness, or other circumstances.

A condition caused pseudo strabismus can make it seem as if a baby’s eyes are crossed. However, this is not true strabismus, as it is usually the result of a wide nasal bridge or excess skin covering the inner eye making it appear as if the eyes are crossed. The cross-eyed effect disappears as the child’s facial features grow.

True strabismus is typically noticed in children by the time they reach 3 years of age. However, strabismus can occur later, as a child matures and even in adulthood. Children do not outgrow strabismus, and the condition will only worsen if left untreated. Is it recommended that all children four months or older who exhibit signs of strabismus been seen by an eye doctor.

Causes of Strabismus

  • Inadequate eye muscle control
  • Problems with the signal transmission from nerves to the eye muscles
  • An issue in the control center of the brain responsible for movement of the eye
  • A family history of strabismus
  • Extreme farsightedness
  • Medical conditions, such as cerebral palsy, Down syndrome, and stroke
  • Eye or head injuries

Types of Strabismus
The types of strabismus are classified according to the following:

  • Hypertropia – the eye turns upward
  • Hypotropia – the eye turns downward
  • Esotropia – the eye turns inward
  • Exotropia – the eye turns outward
  • Alternating – the turning eye alternates between the left one and the right one
  • Constant – eye turning occurs all of the time
  • Intermittent – eye turning occurs occasionally
  • Unilateral – the same eye always turns

The two most common types of this eye condition are:

  • Accommodative esotropia is typically caused by untreated farsightedness. Signs of this type of strabismus include double vision, eyes that turn inward, the need to turn or angle the head to see an object, and need to close one eye when focusing on something close.
  • Intermittent exotropia generally occurs when the eyes cannot work together to focus on an object and, instead, focus beyond the range of the object. Symptoms can include difficulty reading, eye strain, headaches, and the need to close one eye when looking at something in bright sunlight or at a distance.

Diagnosing & Treating Strabismus
Proper diagnosis and treatment of strabismus is important to maintain good vision. If strabismus goes untreated, the brain begins to disregard images transmitted by the impacted eye. This can result is diminished vision and development of amblyopia, also called lazy eye.

Diagnosing strabismus entails a thorough examination of the eyes, especially how the move and how they focus on objects. Other aspects of the exam include:

  • An assessment of prior health history, medication use, and other factors that may contribute to eye symptoms
  • Testing of visual acuity
  • Refraction 
  • Eye health evaluation

Caught early, the prognosis for overcoming strabismus is excellent. Strabismus treatments include:

  • Prescriptions glasses
  • Prism lenses
  • Vision therapy at home or at an optometrist’s office
  • Surgery on the eye muscles


Anatomy of the Human Eye

Anatomy of the Human Eye

Eye Muscles

Eye Muscles

The Fundus

The Fundus

The Hypothalamus

The Hypothalamus

Visual Projection Pathway

Visual Projection Pathway