Both children and adults can suffer from eye muscle disorders. Dr. Alan Scott is our Ophthalmology specialist for eye muscle disorders. Early detection in children can prevent vision loss.
Strabismus is a visual defect in which the eyes are misaligned. One eye may look straight ahead, while the other turns in or out, up or down. Approximately 4% of all children in the United States have strabismus. It occurs equally in males and females. The misalignment may be present all of the time or it can come and go. And, the misaligned eye can even change. The exact reason for the misalignment of the eyes leading to strabismus is not fully understood. Strabismus is a term that describes many eye muscle disorders. Strabismus in children with normal vision, both eyes aim at the same spot. The brain then puts the two pictures into a single, three-dimensional image. This blending or fusing of the two pictures gives us depth perception.
Esotropia is an eye misalignment where the eye turns inward towards the nose. It can affect one or both eyes and can alternate between the two eyes.
Exotropia is a misalignment in which the eye turns outward, away from the nose.
Hypertropia is an upward gaze or appearance of the eye while the other eye stays straight and fixates normally. When one eye turns, two different pictures are sent to the brain. In a child, the brain learns to ignore the picture from the misaligned eye, and sees only the image from the straight one. This causes poor vision in the misaligned eye. It takes away the ability to have and develop depth perception.
How is the diagnosis made?
Strabismus can be diagnosed during an eye exam. It is recommended that all children have their vision checked by their pediatrician, family doctor or ophthalmologist at or before their 4th birthday.
What are the treatment options?
In some cases, eyeglasses can be prescribed that may strengthen the weaker eye. Covering or patching the stronger eye is often used. Surgery may be required to realign or balance the eye muscles.
What can a parent look for?
Parents can watch for one-eyed squinting when the children go outside into the sun. Abnormal head positioning, such as a chin tuck, or the head tilting to one side or the back, could possibly indicate a possible muscle imbalance. Another technique for detecting strabismus in children is to watch for equal light reflexes in the child's pupils. Photographs with the child looking straight ahead at the camera, are good for determining if the light reflexes are equal or not. If there is any question about whether or not your child has an imbalance, a visit with a pediatric ophthalmologist would be the best way to know for sure.
The most important thing for parents to remember is that strabismus can cause permanent loss of vision. Early diagnosis and treatment can keep this from happening. Strabismus in adults as discussed earlier, strabismus is a condition in which the eyes are misaligned and pointed in different directions. Most adults that have strabismus have had it since childhood. However, strabismus can occur in adults that have had no childhood history of misalignment. If there has been no prior history, a doctor may evaluate the patient for medical or neurological causes such as: Diabetes, Thyroid disease, Brain tumors, Strokes, High blood pressure, Head trauma, Other neurological disorders.
What are the symptoms of adult strabismus?
If the strabismus has been present since early childhood, the symptoms are usually minimal. If it develops later, the most common symptom is double vision. Other symptoms may be eyestrain, headaches, discomfort while reading, or holding their head in abnormal positions to focus on an object.
How is adult strabismus treated?
There is a common misconception that strabismus in adults is difficult or impossible to treat. Actually, adults with strabismus have many different treatment options including: Eye exercises, Special glasses with prisms, BOTOX® Cosmetic injections, Eye surgery.
Amblyopia or "Lazy eye"
Amblyopia is poor vision in an eye that did not develop normal sight during early childhood. It is sometimes called "lazy eye". Usually, only one eye is affected. This condition is a common one, affecting about 2 or 3 out of every 100 people. Amblyopia is caused by any condition that affects normal use of the eyes and visual development. In many cases, the conditions associated with this problem are inherited. Children in a family with a history of amblyopia or misaligned eyes should have an ophthalmologist check them early in life. Amblyopia occurs most commonly with misaligned or crossed eyes. The crossed eye "turns off" to avoid double vision and the child uses only the better eye. An eye disease such as a cataract may also lead to amblyopia. Any factor that prevents a clear image from being focused inside the eye can lead to the development of amblyopia.
How is it treated?
To correct this problem a child must be made to use the weak eye by patching or covering the strong eye, often for weeks or months. Even after vision has been restored in the weak eye, part-time patching may be required over a period of years to maintain the vision. Eyeglasses can be used to treat amblyopia and may also be used along with patching to improve vision. In another form of therapy for amblyopia, the doctor may use special eye drops to blur the vision in the good eye, which would force the child to use the weaker eye for focusing. The good news is that the loss of vision is preventable. The success also depends on how severe the amblyopia is, and how old the child is when the treatment is started. If the problem is detected and treated early, vision can improve for most children.
Frequently asked Questions
Q. What is a pediatric ophthalmologist?
A. A pediatric ophthalmologist is a medical doctor (MD) who has completed at least 5 to 6 years of post-graduate training after 4 years of medical school. A pediatric ophthalmologist is specially trained to evaluate and treat both medical and surgical eye conditions in children. Because they are MD’s, they are trained to see your child’s eye conditions in the context of any other health issues.
Q. How long will my child’s eye exam take?
A. The first time your child visits our office a complete history is taken, followed by a thorough exam. This typically includes dilation of the eyes with eye drops and screening for refractive error (nearsightedness, astigmatism, etc.). Some children may take longer than others, depending on their age and cooperation, but a good rule of thumb is to allow 1 to 1 1/2 hours for your first visit.
Q. What is the "right" age for a first eye exam?
A. At any age, if there is a suspected problem. Otherwise, a general guideline is between three and four years of age, with the examination including measurement of visual acuity, eye alignment, motility, refraction, and fundoscopy (an examination of the back of the eye). One of the most important aspects of the examination is to identify conditions that are only treatable at an early age.
Q. My child seems to see fine. How can I tell if there is a problem?
A. Both you and you child may be unaware there is any problem since a decrease in vision in one eye is often compensated for by the other eye. If no problems are apparent, your child should receive a careful vision screening between the ages of three and four.
Q. How can the doctor effectively examine my stubborn two year old?
A. Patience, and a few tricks of the trade. Your child does not have to speak, or even be entirely cooperative to be examined. With special eye drops and equipment, the doctor can see into the eye and measure to see if your child needs glasses, even if they can’t read! The doctor will also check for any eye misalignment or other ocular problem.
Q. Do you prescribe “vision therapy”?
A. No. Ophthalmologists view the eye as a wonderfully complex organ which is, literally and physically, a direct extension of the brain and neurological (central nervous) system. For further information, we strongly recommend a review of the policy statement on learning disabilities and dyslexia published by the American Academy of Ophthalmology and American Academy of Pediatrics.
Q. My child complains of headaches. Is this an eye problem?
A. Maybe. Sometimes, a need for glasses will cause headaches, but there are a number of other ocular and medical conditions that can cause eye pain and headaches. These types of complaints should first be investigated by your pediatrician, who may refer your child to a pediatric ophthalmologist for additional investigation.
Q. My child sits close to the TV. Is there anything wrong?
A. Most children like to sit close to the TV because the picture is bigger the closer they are to the screen. Some of them may need glasses, but sitting close to the TV is not a definitive indication of eye problems.
Q. My child blinks a lot. Is there anything wrong?
A. Often, blinking is a nervous habit or tic. It is usually a good idea to make sure there is no underlying eye problem, especially if there are associated symptoms such as redness, tearing, rubbing, etc.
Q. I wear glasses. Does this mean my child will need glasses?
A. Maybe. Certain eye conditions are hereditary. If there is a strong family history of any eye condition, early examination by a pediatric ophthalmologist may be advisable.
Q. Does the doctor have to use eye drops to examine my child?
A. Usually, yes. Dilating the pupils with an eye drop allows the doctor to get a good look at the inside of the eye. In addition, the eye drop relaxes the “focusing muscles” that attach onto the lens of the eye. This lets them objectively measure refractive error (i.e., if glasses might be needed).
Q. Are there any long-term effects of the eye drops?
A. Depending on the drop used, your child’s pupils may be dilated up to a day or so. Near vision (for reading) might be blurred for several hours, and there can be a bit of sensitivity to direct sunlight. Most children return to school on the day of the eye exam.
Q. What types of surgery do pediatric ophthalmologists perform?
A. The most common surgeries are those that straighten eye alignment (strabismus or “eye muscle surgery). Another common procedure is probing and irrigation of blocked tear ducts. When necessary, the doctors also perform surgery on the eyelids and tissue around the eyes.