CAUSES OF HEARING LOSS IN ADULTS:

Hearing loss in adults has many causes such as, exposure to noise, disease or infection, ototoxic drugs, tumors, trauma and the aging process. Some examples of causes of hearing loss in adults are described below:

Presbycusis

Presbycusis is the most common cause of sensory hearing loss in the adult population. This loss is caused by some degenerative changes (in the auditory system) associated with the aging process. The hearing loss is progressive in nature with the high frequencies affected first. While the process begins after age 20-30, it is often at ages 55 to 65 that the high frequencies in the speech range begin to be affected.

Noise-Induced Hearing Loss

This is the second most common cause of acquired sensorineural hearing loss. Prolonged exposure to loud noise causes damage to the hair cells in the cochlea and results in this type of permanent hearing loss. The noise-induced hearing loss usually develops gradually and painlessly. Sometimes the hearing loss can occur as a result of an acoustic trauma, or a single exposure or very few exposures to very high levels of sound. When this happens, a complete breakdown of the Organ of Corti in the inner ear occurs. When the hair cells become damaged from prolonged exposure to loud noises such as music, machines, motors and other noise producing equipment or to a single but very loud noise exposure such as gunfire or an explosion, they are unable to be stimulated properly by an incoming sound signal. Once these hair cells have become damaged there is no way for them to be repaired.

Otitis Media

This is the condition often referred to as an ear infection. When otitis media occurs, fluid accumulates behind the eardrum in the middle ear space. This space is normally air filled in a healthy ear. The fluid arises because of the inability of the Eustachian tube to adequately function and keep the pressure equalized to atmospheric pressure in the middle ear space. The Eustachian tube dysfunction can be the result of allergies, infection in the upper respiratory tract.

Otosclerosis

This is a progressive ear disease involving the middle ear bony capsule, specifically affecting the movement of the stapes (one of the three small bones in the middle ear).

Meniere’s Disease

This is an inner ear disease and is characterized by progressive fluctuating sensorineural hearing loss, vertigo (dizziness) , and tinnitus (ringing in the ear).

Ototoxic Drugs

Drugs used to treat some diseases are damaging to the auditory system (ototoxic) and cause hearing loss. The more common drugs that are particularly toxic to the ear are certain antibiotics (such as Streptomycin, Kanamycin, Neomycin), Salicylates in large quantities (drugs containing aspirin), and quinine. Some drugs used in chemotherapy regimens are reported to be ototoxic. The damage caused by these drugs often depends on the dose administered and length of time used and is usually permanent.

Acoustic Neuroma

This is an example of a tumor that causes sensorineural hearing loss. Acoustic neuromas arise in the 8th cranial nerve (acoustic nerve). The first symptom could be a unilateral hearing loss, tinnitus in one ear, or vertigo.

Trauma

Trauma can cause a conductive, sensorineural or even a mixed hearing loss. Damage can occur to the as a result of trauma to the ear itself or to the side of the head. Examples include fractures of the temporal bone, puncture of the ear drum by foreign objects, , and sudden changes in air pressure.

Sudden Hearing Loss

This is an abrupt loss of hearing. Sudden hearing loss of known causes may be due to drugs, trauma, infection, or disease. There are, however, many instances when no cause can be found. There are two theories as to what happens in these cases: Vascular Occlusion which is the abrupt interference of blood supply to the cochlea and Viral Labrynthitis (viral infection of the inner ear), which produces damage to the inner ear structures.

SYMPTOMS OF HEARING LOSS:

Why is folic acid important?

Vitamin B9 includes both folate and folic acid and is important for several functions in the body.

Folic acid is vital for making red blood cells, as well as:

• the synthesis and repair of DNA and RNA
• aiding rapid cell division and growth
• enhancing brain health, although the evidence is mixed and more research is needed
• age-related hearing loss

It is particularly important for women who are pregnant to consume enough folic acid. This helps prevent the fetus from developing major congenital deformities of the brain or spine, including neural tube defects, such as spina bifida and anencephaly.

Women planning to get pregnant should take folic acid supplements for a full year before conception to reduce the risk of these developments.

Folic acid is thought to play a preventive role in a range of conditions.

Types of diseases which causes by deficiency of Folic acid as follows:

Autism

A recent study connected folic acid deficiency with autism. The investigators concluded: “Periconceptional folic acid [before conception and during early pregnancy] may reduce [autism spectrum disorder] risk in those with inefficient folate metabolism.”

Cleft lip and palate

A literature review carried out in 2014 concluded that folic acid supplementation might reduce the risk of a cleft palate.

Rheumatoid arthritis

Folic acid is often used to support a methotrexate prescription for rheumatoid arthritis.

Methotrexate is an effective medicine for this condition. However, it is also known to remove folate from the body. This can cause gastrointestinal symptoms for between 20 and 65 percent of people who use the drug.

However, folic acid supplements have been shown to reduce the gastrointestinal side effects of methotrexate by 79 percent. Speak to a doctor for recommendations on how much to take, and how often. 1 milligram (mg) per day is often prescribed.

Deficiency

Folic acid deficiency occurs when not enough folate or folic acid is present in the body.

Aside from anemia and congenital deformities, folic acid deficiency can result in other health problems, including:

• a higher risk of developing clinical depression
• possible problems with memory and brain function
• a higher risk of potentially developing allergic diseases
• a higher potential long-term risk of lower bone density

The Medical Journal of Australia advised in January 2011 that the prevalence of folate deficiency in the country had dropped considerably since introducing the compulsory fortification of wheat flour in breadmaking.

Deficiency anemia

Individuals can develop folic acid deficiency anemia if they do not consume enough folic acid.

As folate is important for producing and maintaining red blood cells, inadequate levels can mean that there are not enough red blood cells to supply the body with a healthy level of oxygen.

This condition can appear in people who require higher quantities of folate and are not taking supplements, such as women who are pregnant and lactating.

Folic acid deficiency anemia can occur in people with underlying conditions, such as sickle cell anemia. It can also affect people with conditions that affect folate absorption. Alcohol abuse or kidney disease can reduce the ability of the body to effectively absorb folate.

Some medications, such as those used for treating rheumatoid arthritis, cancer, and seizures, may increase the risk of folic acid deficiency anemia.

The signs and symptoms of folic acid deficiency disease include:

• fatigue
• feeling weak
• sores around the mouth
• memory and cognition difficulties
• irritable mood
• loss of appetite
• weight loss

People with folic acid deficiency anemia are given folic acid pills for daily use. Once folate levels return to normal, the body can produce enough blood cells to allow normal function.

Side effects

There are no serious side effects when taking folic acid. In rare cases, individuals report an upset stomach.

Even if a person takes more folate than needed, there is no cause for concern. Because folic acid is water-soluble, any excess will be naturally passed in urine.

Who should take it?

All women who are pregnant or planning to become pregnant should consume more folic acid, according to March of Dimes, a research organization focused on preventing deformity and death in newborn infants.

They also recommend that women take folic acid before getting pregnant as well as during the first 4 weeks following conception.

Every woman capable of getting pregnant should be taking daily folic acid supplements. Women over the age of 14 years should take 400 micrograms (mcg) per day, and this should increase to 600 mcg during a pregnancy.

Women should maintain a daily intake of 500 mcg.

Multiple Sclerosis – Literally, “many hardenings,” MS is a disease of unknown cause that manifests as multiple hard plaques of degeneration of the insulating layer of nerve fibers in the central nervous system. The loss of insulation allows “short circuiting” of nerve impulses. Depending upon where the degeneration occurs, patients may suffer paralysis, sensory disturbances or blindness.

Cerebrovascular accident (CVA) – the fancy name for a “stroke”. A blood vessel in the brain may burst causing internal bleeding. Or, a clot may arise in a brain blood vessel (a thrombus), or arise elsewhere (embolus) and travel to get stuck in a brain vessel which then deprives brain tissue of oxygen. Depending upon the area of the brain involved, the patient may suffer paralysis, loss of speech or loss of vision.

Transient Ischemic Attack (TIA) – “Ischemia” was introduced previously in the circulatory diseases module referring to the heart. It literally means “not quite enough blood”. A short period of insufficient blood supply to the brain can have the same signs and symptoms as a stroke such as weakness in an arm, a partial loss of vision, but the problem lasts less than 24 hours. People who get TIA’s are at increased risk of having a stroke in the future.

Epilepsy – a Greek word for “seizure.” Convulsions is another term used. Seizures may have many causes and not all seizures are epilepsy. High fevers in young children may trigger seizures which are short in duration, easily controlled and, typically, have no permanent aftereffects. Epilepsy is a specific condition which may occur at any age, seizures are more intense, longer lasting in duration, and recur with some frequency. The condition may be controlled with medication, or if unresponsive to drugs, may require surgery.

Aphasia – loss of speech. The speech centers are located on the left side of the brain in a majority of people. If someone suffers a “stroke” (cerebrovascular accident-CVA), or traumatic brain injury, and it involves the left side of the brain, they may suffer speech impediments that vary over a spectrum of problems from difficulty in finding the right word, speaking slowly and with difficulty, or complete loss of speech. Actually, there are two speech centers. Injury described above involves the motor speech area, the area of the brain that produces language by integrating thoughts of speech with the movements of the larynx, lips and tongue. There is a second speech area, the receptive or sensory area, that enables us to understand speech. Injury to the latter results in still fluent speech, but the individual does not understand what they are hearing.

 

Anencephaly occurs early in the development of an unborn baby. It results when the upper part of the neural tube fails to close. Why this happens is not known. Possible causes include environmental toxins and low intake of folic acid by the mother during pregnancy

Causes:

Anencephaly is one of the most common neural tube defects. Neural tube defects are birth defects that affect the tissue that grows into the spinal cord and brain.

Anencephaly occurs early in the development of an unborn baby. It results when the upper part of the neural tube fails to close. Why this happens is not known. Possible causes include environmental toxins and low intake of folic acid by the mother during pregnancy.

Anencephaly occurs in about 1 out of 10,000 births. The exact number is unknown, because many of these pregnancies result in miscarriage. Having one infant with this condition increases the risk of having another child with neural tube defects.

This rare type of headache doesn’t stop. It causes pain on one side of your face or head.

Doctors don’t know what causes this “continuous headache.” But women seem to get it more often than men.

With the right treatment, though, most people can get nearly complete relief from the pain.

Symptoms

People with hemicrania continua describe a dull ache or throb that’s interrupted by pain that is:

• Jolting
• Sharp
• Stabbing

These attacks usually happen three to five times a day.

Some people will have these headaches steadily for months or years. For others, the pain will go away for weeks or months, then come back.

The headaches often have some of the same symptoms as other kinds. This overlap can make them tricky for doctors to diagnose.

Like migraines, they can cause:

• Nausea or vomiting
• Sensitivity to noise or light
• Throbbing pain

Hemicrania continua also shares features of cluster headaches. For example, people who have it may have problems with how part of their nervous system works. That causes symptoms that happen on the painful side of the face and head, including:

• Stuffy or runny nose
• Nosebleeds (which are rare)
• Tearing, redness, or irritation of the eyes
• Drooping eyelids
• Sweating

Some things tend to make symptoms worse, such as:

• Stress
• Changes in sleep patterns
• Bright lights
• Fatigue
• Overdoing exercise
• Alcohol

About 10% of people have symptoms when they:

• Feel pressure on their neck
• Flex or rotate their neck

Doctors can make a diagnosis of hemicrania continua if you’ve had pain consistently, without it switching sides or disappearing even briefly, for at least 3 months.

Treatments

Some anti-inflammatory medications ease hemicrania continua headaches. Indomethacin, a nonsteroidal anti-inflammatory drug (NSAID), often gives fast relief. One way doctors know that you have hemicrania continua is if your headaches go away after a dose of the drug. But some people may need more testing — such as an MRI — to look into their symptoms.

Daily doses of indomethacin for hemicrania continua typically range from 25 to 200 milligrams. A common side effect of the drug is irritation of the lining of the stomach and digestive tract. So, people who take it may also need medication to help their stomach make less acid.

If the side effects of indomethacin are too much for you, another NSAID, celecoxib, may also help.

Tricyclic antidepressants, like amitriptyline, can also prevent these headaches.

What is ALS?

Amyotrophic lateral sclerosis (ALS) is a rare group of neurological diseases that mainly involve the nerve cells (neurons) responsible for controlling voluntary muscle movement. Voluntary muscles produce movements like chewing, walking, breathing and talking. The disease is progressive, meaning the symptoms get worse over time. Currently, there is no cure for ALS and no effective treatment to halt, or reverse, the progression of the disease.

ALS belongs to a wider group of disorders known as motor neuron diseases, which are caused by gradual deterioration (degeneration) and death of motor neurons. Motor neurons are nerve cells that extend from the brain to the spinal cord and to muscles throughout the body. These motor neurons initiate and provide vital communication links between the brain and the voluntary muscles.

Messages from motor neurons in the brain (called upper motor neurons) are transmitted to motor neurons in the spinal cord and to motor nuclei of brain (called lower motor neurons) and from the spinal cord and motor nuclei of brain to a particular muscle or muscles.

In ALS, both the upper motor neurons and the lower motor neurons degenerate or die, and stop sending messages to the muscles. Unable to function, the muscles gradually weaken, start to twitch (called fasciculations), and waste away (atrophy). Eventually, the brain loses its ability to initiate and control voluntary movements.

Early symptoms of ALS usually include muscle weakness or stiffness. Gradually all muscles under voluntary control are affected, and individuals lose their strength and the ability to speak, eat, move, and even breathe.

Most people with ALS die from respiratory failure, usually within 3 to 5 years from when the symptoms first appear. However, about 10 percent of people with ALS survive for 10 or more years.

Causes and types

It is unclear exactly what causes ALS. There are different types, according to their signs and symptoms and whether or not there is a clear genetic association.

ALS can be sporadic or familial.

Sporadic ALS occurs randomly, and it accounts for 90 to 95 percent of cases. There is no clear risk factor or cause.

Familial ALS is inherited. Around 5 to 10 percent of cases are familial. The child of a person with ALS will have a 50 percent chance of developing the condition. Rarely, it can affect a person in their teens. Researchers are investigating which genes are involved.

Other possible causes of ALS include:

• Disorganized immune response: The immune system may attack some of the body’s cells, possibly killing nerve cells.
• Chemical imbalance: People with ALS often have higher levels of glutamate, a chemical messenger in the brain, near the motor neurons. Glutamate in high quantities is known to be toxic to nerve cells.
• Mishandling of proteins: If proteins are not processed correctly by nerve cells, abnormal proteins could potentially accumulate and cause the nerve cells to die.

Possible environmental factors

Environmental factors may also play a role.

One study has reported that military personnel deployed in the Gulf region during the 1991 war were more likely to develop ALS than military personnel deployed elsewhere.

Some possible links have been found between ALS and exposure to:

• mechanical or electrical trauma
• military service
• high levels of exercise
• high levels of agricultural chemicals
• high levels of a variety of heavy metals

However, there is no conclusive evidence that specific lifestyle changes can decrease the risk.

Signs and symptoms

The symptoms of ALS usually appear when a person is in their late 50s or early 60s, but it can happen at other ages.

Progression varies between individuals. In the early stages, signs and symptoms may be barely noticeable, but the weakness becomes more visible over time.

Common symptoms include:

• difficulty carrying out daily activities, including walking
• increased clumsiness
• weakness in the feet, hands, legs, and ankles
• cramping and twitching in the arms, shoulders, or tongue
• difficulty maintaining good posture and holding the head up
• uncontrolled outbursts of laughing or crying, known as emotional lability
• cognitive changes
• slurring of speech and difficulty with voice projection
• pain
• fatigue
• problems with saliva, and mucus
• difficulty breathing and swallowing, in the later stages

Progressive muscle weakness occurs in all cases of ALS, but this may not be the first indication of the condition.

Early symptoms often include clumsiness, abnormal limb fatigue, muscle cramps and twitches, and slurred speech. Symptoms will spread to all parts of the body as ALS progresses.

Some people may have problems with decision-making and memory, eventually leading to a form of dementia called frontotemporal dementia.

Emotional lability can cause fluctuations in mood and emotional response.

Treatment and prevention

There is no cure for ALS, so treatment aims to alleviate symptoms, prevent unnecessary complications, and slow the rate of disease progression.

ALS can cause a range of physical, mental, and social changes, so a team of specialists will often help patients manage their symptoms and care, improve their qualify of life, and prolong survival.

Riluzole (Rilutek) was approved for ALS treatment by the Food and Drug Administration (FDA) in 1995, and it appears to slow the progression of the disease. It may work by reducing the body’s levels of glutamate, an excitotoxin that has been linked to neuronal damage.

In May 2017, Radicava (Edaravone) was approved to treat ALS. It may slow the decline in physical function by one third.

A number of research projects are looking at ways to use new and existing drugs to treat different aspects of ALS. Doctors can also prescribe medications to treat the different symptoms.

Therapy

Physical therapy can help people with ALS manage pain and address mobility issues.

A physical therapist can provide help and information with:

• low-impact exercises to enhance cardiovascular fitness and overall well-being
• mobility aids, such as walkers and wheelchairs
• devices to make life easier, such as ramps

Occupational therapy can help a patient maintain their independence for longer by:

• helping patients choose adaptive equipment and assistive technologies to help them keep up their daily routines
• train them in ways to compensate for hand and arm weaknesses

Breathing therapy may be needed in time, as the respiratory muscles get weaker.

Breathing devices can help the patient breathe better at night. Some patients may need mechanical ventilation. One end of a tube is connected to a respirator, while the other end is inserted into the windpipe through a surgically-created hole in the neck, or tracheostomy.

Speech therapy is useful when ALS begins to make it harder to talk. Speech therapists can help by teaching adaptive techniques. Other methods of communication include writing and computer-based communications equipment.

Nutritional support is important, as difficulty with swallowing can make it hard to get enough nutrients. Nutritionists can advise on preparing nutritious meals that are easier to swallow. Suction devices and feeding tubes may help.

Mastoiditis is a bacterial infectionof the mastoid  air cells surrounding the inner and middle ear. The mastoid bone, which is full of these air cells, is part of the temporal bone of the skull. The mastoid air cells are thought to protect the delicate structures of the ear, regulate ear pressure and possibly protect the temporal bone during trauma.

When the mastoid cells become infected or inflamed, often as a result of an unresolved middle ear infection (otitis media), mastoiditis can develop. Because so many vital structures pass through the mastoid, infection may spread outside of the mastoid bone and cause serious health complications.

Acute mastoiditis typically affects children, but adults can also be affected.

Some people have chronic mastoiditis, an ongoing infection of the middle ear and mastoid that causes persistent drainage from the ear.

Mastoiditis Causes

As mentioned above, mastoiditis most often develops as a result of a middle ear infection. Bacteria from the middle ear can travel into the air cells of the mastoid bone. Less commonly, a growing collection of skin cells called a cholesteatoma, may block drainage of the ear, leading to mastoiditis.

Mastoiditis Symptoms :

Mastoiditis symptoms may include:

• Fever, irritability, and lethargy
• Swelling of the ear lobe
• Redness and tenderness behind the ear
• Drainage from the ear
• Bulging and drooping of the ear

Mastoiditis Complications :

Mastoiditis complications may include:

• Facial paralysis
• Nausea, vomiting, vertigo (labyrinthitis)
• Hearing loss
• Brain abscess or meningitis
• Vision changes or headaches (blood clots in the brain)

Mastoiditis Treatments :

Antibiotic therapy is the mainstay of treatment for both acute and chronic mastoiditis.

If you or your child is diagnosed with acute mastoiditis, you may be put in the hospital to receive treatment and care by an otolaryngologist, a doctor who specializes in ear, nose, and throat disorders. Antibiotics will be given through an IV (intravenous line) to treat the infection.

Surgery may also be needed to drain the fluid from the middle ear, called a myringotomy. During a myringotomy, the doctor makes a small hole in the eardrum to drain the fluid and relieve pressure from the middle ear. A small tube may be inserted into the middle ear to to keep the hole from closing so as to allow for continued drainage. Typically, the tube will fall out on its own after six to 12 months.

 

If the symptoms don’t quickly improve on IV antibiotics, or complications, like an abscess or bone erosion are present, surgery to remove the infected mastoid bone may be recommended. This is called a mastoidectomy.

Chronic mastoiditis is treated with oral antibiotics, eardrops, and regular ear cleanings by a doctor. If these treatments do not work, surgery may be necessary to prevent further complications.

If left untreated, mastoiditis can cause serious, even life-threatening, health complications, including hearing loss, blood clot, meningitis, or a brainabscess. But with early and appropriate antibiotic treatment and drainage, these complications can usually be avoided and you can recover completely.

If you have an earache, discharge or trouble hearing, see your doctor.  He will decide if you need antibiotics to help prevent mastoiditis and other serious health complications.

Spinal fractures caused by trauma represent a serious orthopedic injury. Fractures that occur as a result from a high velocity accident are most commonly in the mid to low back. High velocity accidents are associated with trauma from motor vehicle accidents, a fall from height, or sporting accidents. Patients with high energy trauma or who lose consciousness require urgent emergency evaluation and treatment. The most common symptom of a spinal fracture is moderate to severe pain in the back that is increased with movement.

Fractures of the neck usually occur as a result of high energy trauma and are uncommon in other situations. There are seven bones in the neck and a break in any of those bones may be referred to as a “broken neck.” Any fracture in the neck has serious consequences because the spinal cord runs through the center of the cervical vertebrae. Damage or injury to the spinal cord can result in paralysis or death. All patients with trauma who develop cervical fractures should be evaluated in an emergency room setting.

FRACTURES  :

Low Energy Fractures

People can develop spinal fractures unrelated to trauma; they usually have weakened bones from osteoporosis, tumors, or other medical conditions. Fractures that occur during daily activities are most commonly associated with conditions that may weaken the bone including osteoporosis, spinal tumors or spinal infections. For patients with low energy fractures due to osteoporosis these fractures are called a compression fracture. Treatment options include observation, bracing, and pain management. For some patients a minimally invasive procedure including vertebroplasty and kyphoplasty may improve pain and help to prevent further compression.

Types of Spinal Fractures

There are several types of spinal fractures based on pattern of injury and the extent of spinal cord injury. Below are the more common fractures.

Compression Fracture: This is often caused by osteoporosis or a tumor and rarely has spinal cord or nerve involvement. The front of the vertebra fractures and loses height however the back, posterior, part remains stable. It can be painful or asymptomatic and is usually a stable fracture.

Axial Burst Fraction: This is usually caused from a fall from a significant height, landing on the feet. The vertebra loses height on both the front and back side; depending on the stability of the fracture this may require surgery.

Chance Fracture: This fracture is known as a “seat-belt injury” and is caused by a violent forward flexed injury.  The vertebra is pulled apart, often from a car accident where the upper body is pulled forward while the pelvis is stabilized by a lap only seat belt

PREVENTION

Prevention from high impact accidents can save your life. Always wear a seat belt when riding in a car. Always wear protective equipment when playing sports, riding bicycles, motorcycles or even horses. Obey all regulations in place for your safety. Never dive head first into shallow pool or swimming area.

TREATMENT

Treatment for spinal fractures will depend on the location and type of fracture as well as other the amount of neurologic compression. Minor fractures can be treated with cervical bracing. More complex fractures or fractures with spinal cord compression may require traction, surgery, or some combination of the above. For patients with neurologic compromise or unstable fractures, surgical intervention may be appropriate in order to stabilize the fracture, remove any nerve compression and assist with healing. For most patients, non-operative treatment is appropriate. Rehabilitation is an essential part to the treatment plan once the spinal fracture has healed. Rehabilitation allows patients to reduce pain and minimize disability with a hopeful full return to their functional level before the injury.

 

Strabismus is a failure of the two eyes to maintain proper alignment and work together as a team.

If you have strabismus, one eye looks directly at the object you are viewing, while the other eye is misaligned inward (esotropia, “crossed eyes” or “cross-eyed”), outward (exotropia or “wall-eyed”), upward (hypertropia) or downward (hypotropia).

Strabismus can be constant or intermittent. The misalignment also might always affect the same eye (unilateral strabismus), or the two eyes may take turns being misaligned (alternating strabismus).

To prevent double vision from congenital and early childhood strabismus, the brain ignores the visual input from the misaligned eye, which typically leads to amblyopia or “lazy eye” in that eye.

According to the American Association for Pediatric Ophthalmology and Strabismus, approximately 4 percent of the U.S. population has crossed eyes or some other type of strabismus.

Strabismus Symptoms And Signs

The primary sign of strabismus is a visible misalignment of the eyes, with one eye turning in, out, up, down or at an oblique angle.

When the misalignment of the eyes is large and obvious, the strabismus is called “large-angle,” referring to the angle of deviation between the line of sight of the straight eye and that of the misaligned eye. Less obvious eye turns are called small-angle strabismus.

Typically, constant large-angle strabismus does not cause symptoms such as eye strain and headaches because there is virtually no attempt by the brain to straighten the eyes. Because of this, large-angle strabismus usually causes severe amblyopia in the turned eye if left untreated.

Less noticeable cases of small-angle strabismus are more likely to cause disruptive visual symptoms, especially if the strabismus is intermittent or alternating. In addition to headaches and eye strain, symptoms may include an inability to read comfortably, fatigue when reading and unstable or “jittery” vision. If small-angle strabismus is constant and unilateral, it can lead to significant amblyopia in the misaligned eye.

Both large-angle and small-angle strabismus can be psychologically damaging and affect the self-esteem of children and adults with the condition, as it interferes with normal eye contact with others, often causing embarrassment and awkwardness.

Newborns often have intermittent crossed eyes due to incomplete vision development, but this frequently disappears as the infant grows and the visual system continues to mature. Most types of strabismus, however, do not disappear as a child grows.

Routine children’s eye exams are the best way to detect strabismus. Generally, the earlier strabismus is detected and treated following a child’s eye exam, the more successful the outcome. Without treatment, your child may develop double vision, amblyopia or visual symptoms that could interfere with reading and classroom learning.

What Causes Strabismus?

Each eye has six external muscles (called the extraocular muscles) that control eye position and movement. For normal binocular vision, the position, neurological control and functioning of these muscles for both eyes must be coordinated perfectly.

Strabismus occurs when there are neurological or anatomical problems that interfere with the control and function of the extraocular muscles. The problem may originate in the muscles themselves, or in the nerves or vision centers in the brain that control binocular vision.

Genetics also may play a role: If you or your spouse has strabismus, your children have a greater risk of developing strabismus as well.

Accommodative Esotropia

Occasionally, when a farsighted child tries to focus to compensate for uncorrected farsightedness, he or she will develop a type of strabismus called accommodative esotropia, where the eyes cross due to excessive focusing effort. This condition usually appears before 2 years of age but also can occur later in childhood. Often, accommodative esotropia can be fully corrected with eyeglasses or contact lenses.

Strabismus Surgery

In most cases, the only effective treatment for a constant eye turn is strabismus surgery. If your general eye doctor finds that your child has strabismus, he or she can refer you to an ophthalmologist who specializes in strabismus surgery.

The success of strabismus surgery depends on many factors, including the direction and magnitude of the eye turn. In some cases, more than one surgery may be required. The strabismus surgeon can give you more information about this during a pre-surgical consultation.

Strabismus surgery also can effectively align the eyes of adults with long-standing strabismus. In many cases of adult strabismus, however, a significant degree of amblyopia may remain even after the affected eye is properly aligned. This is why early treatment of strabismus is so important.

The earlier strabismus is treated surgically, the more likely it is that the affected eye will develop normal visual acuity and the two eyes will function together properly as a team.

Non-Surgical Strabismus Treatment

In some cases of intermittent and small-angle strabismus, it may be possible to improve eye alignment non-surgically with vision therapy.

For example, convergence insufficiency (CI) is a specific type of intermittent exotropia in which the eyes usually align properly when viewing a distant object, but fail to achieve or maintain proper alignment when looking at close object, such as when reading, resulting in one eye drifting outward. Convergence insufficiency can interfere with comfortable reading, causing eye strain, blurred vision, double vision and headaches.

There also is some evidence that suggests CI can cause attention problems and affect academic performance in children. A recent study conducted by Mayo Clinic researchers found that children with exotropia (including convergence insufficiency) at an early age were significantly more likely to develop attention deficit hyperactivity disorder (ADHD), adjustment disorder and learning disabilities by early adulthood.

Certain types of strabismus also have been associated with an increased risk of myopia. Another Mayo Clinic study published in 2010 followed 135 children with intermittent exotropia over a 20-year period and found that more than 90 percent of these children became nearsighted by the time they reached their 20s.

On the bright side, it appears non-surgical vision therapy can be an effective treatment for convergence insufficiency. In a study published in Archives of Ophthalmology, 73 percent of 221 children with symptomatic convergence insufficiency had a successful or improved outcome following a 12-week program of office-based vision therapy combined with eye exercises performed at home.

Sometimes, a strabismus surgeon may recommend a program of vision therapy for a period of time after strabismus surgery to treat amblyopia and minor binocular vision problems that might remain after surgery. In these cases, the term “orthoptics” (“ortho” = straight; “optics” = eyes) rather than “vision therapy” might be used to describe this treatment, which may be provided by an orthoptist working closely with the surgeon rather than by an optometrist.