Pediatric Ophthalmology at Baltimore Washington Eye Center serving greater Baltimore & Washington, D.C.

Pediatric Ophthalmology is a subspecialty of Ophthalmology dealing with problems common to, or seen exclusively in, the pediatric or children’s age group.

Children’s eyes and vision are different than adult’s eyes and vision. The brain cells that control our vision are not fully developed, or mature, when we are born. These cells develop throughout the first decade of life. Because of the immaturity of a child's visual system, disorders that may have little effect on an adult’s ability to see can have a profound and life-long effect on a child's vision. Poor vision due to inadequate stimulation of these brain cells, amblyopia, is a common cause of loss of vision in this age group. Some disorders are only seen in children. Some disorders, such as certain types of tumors, may be found in both children and adults, but may have different effects when they occur in children.

The Pediatric Eye Exam

At Baltimore Washington Eye Center your child will have the following testing during the course of their eye exam:

• Visual Acuity
  Your child's vision will be checked. This is possible even in children who do not speak yet. For older children, picture charts, letter games and letter recognition can be used.
• Eye Alignment or Muscle Balance
  Various methods are used to test the alignment of the eyes and make sure the muscles, which move the eye, are functioning normally. This may be done using light reflexes or alternately covering each eye to make sure that they do not move from the straight ahead position.
• Binocular Vision
  These tests are used to make sure that the eyes are not only aligned correctly, but that the brain is using them together as well. If the eyes are properly aligned, it does not always follow that the brain is using them together.  Proper eye alignment is important for the development of depth perception, or the ability to see objects in 3D.
• Refraction
  A refraction is used to measure the "power" of the eye. It determines if your child is nearsighted, farsighted or has astigmatism.  This can be done in infants where they cannot cooperate to tell us how well they are seeing. A special light is placed into their eyes and the light is moved back and forth. The light enters the eye and "bounces" back to the examiner. The way the light behaves as it comes back out through the child's eye can be used to determine the refractive power of the eye. To obtain accurate measurements in young children, the focusing power of the eye must first be neutralized. This is done by placing drops into the eye to dilate the pupil and eliminate their focusing mechanism. These drops often take 30-60 minutes to work.
• Fundus Examination
  We will use specialized instruments, often worn on our head, to look into the back of your child's eye. The retinal blood vessels and the optic nerve, an extension of the brain, can be seen. Because this is an area where blood vessels and portions of the brain can be seen, it is very valuable in helping to diagnose many disorders that can affect the entire body.

Once the examination is complete, your child may be prescribed glasses. Treatment for other problems may also be addressed. If your child received drops, he/she may experience blurry vision until their effect has resolved (anywhere from three to 24 hours). The duration of this effect is dependent on the type of drop used, the color of his/her eyes and the refractive power of the eyes.

About Strabismus or Crossed Eyes

Strabismus is a misalignment of the eyes. It includes in-turned eyes, called Esotropia, out-turned eyes, called Exotropia and other eye muscle disorders. Sometimes children are successfully treated for strabismus only to redevelop strabismus later in life. This may be secondary to the inability of a person to use both eyes together (binocular vision) or other unknown causes. People who have one eye that does not see well when fully corrected with glasses, called Amblyopia, may develop strabismus with time. Most often, the poorer seeing eye drifts outward.

Types of Strabismus

• Congenital Esotropia
  This form of Esotropia (crossed eyes) is also known as Infantile Esotropia.  It usually develops before the child is six months old and is characterized by a large eye turn.  Unlike Accommodative Esotropia, glasses will not correct the eye turn. Amblyopia is common in children with Congenital Esotropia and should be treated early. Once the child's vision is equalized, treatment can be recommended for the eye turn. Eye muscle surgery is the treatment for patients with Infantile Esotropia. The surgery is usually performed on both eyes, although it may also be done on one eye.   The goal of treatment in Infantile Esotropia is to straighten the eyes so that the child can learn to use them together and develop "binocular vision”. The ability to use both eyes together will help to keep them aligned. Studies have shown that early surgical alignment improves the chances of developing binocular vision. Therefore, many pediatric ophthalmologists recommend surgery when the angle of crossing is stable and the vision in each eye is good.
  
  Many children with Congenital Esotropia develop other eye muscle disorders. This occurs even when their eyes have been successfully made straight with surgery. Recurrent Esotropia following surgery for Congenital Esotropia occurs in about 25% of patients. About 75%, can be treated with glasses and do not require further surgery. This is a different type of Esotropia than the original infantile crossing. Up to 75% of patients develop overacting Inferior Oblique Muscles or Dissociated Vertical Deviations. These can occur months to years after the original surgery.  Treatment may require surgery.
  
  As you can see, Infantile Esotropia is a complex disorder. Although surgery is required to treat it, it is only the start of the process. These children must be carefully followed for other problems during the visually immature period of their life.
  
  
• Accommodative Esotropia
  Most children are farsighted. In children, this means that they have the potential to see well at both distance and at near. However, they have to "focus" or accommodate to do so. This is usually not a problem as children have a large "focusing" ability. A reflex exists that makes the eyes want to cross when we try to focus. This normal reflex allows our eyes to maintain alignment when we focus to read material close to us, i.e. our eyes must both turn in a little to work together at near. However, if a child is very farsighted, their eyes will cross when they focus to see well. In this case, they must make a subconscious decision to see well or cross their eyes. The treatment for this type of strabismus is eyeglasses. The child is given glasses to correct their farsightedness. Because they no longer have to focus to see well, they will no longer cross their eyes. Amblyopia is very common in this setting. If Amblyopia is present, in addition to eyeglasses, treatment for the Amblyopia may be required as well. Many children lose some of their farsightedness as they get older and will outgrow their glasses. This is dependent on the initial level of farsightedness and the growth curve of the eye. It is very individualized and therefore it is hard to predict who will outgrow their need for glasses.
  
  
• Intermittent Exotropia
  Intermittent Exotropia is a type of strabismus where one, or both, eyes turn outward (Exotropia) intermittently. It usually begins in the 2-3 year age group. It is first seen infrequently when the child is sick or tired and only when they are looking into the distance. For this reason, in its early stages, it may not be seen in a pediatrician's office, when the child is examined only up close and is well rested.  It generally progresses in frequency and duration with the eye turn occurring earlier in the day and the deviating eye staying out for longer periods of time. Often, the child closes one eye to eliminate the double vision that it may cause. This is especially noticeable in sunlight. As the disorder progresses, the eyes will also start to turn out when looking at close objects as well, i.e. reading. If not treated, the eye may turn out constantly and binocular vision could be lost. Amblyopia can occur in intermittent Exotropia but is uncommon.

About Amblyopia

Amblyopia is the medical term for poor vision in one, or sometimes both eyes. Children are born with poor vision.  As they develop, the eyes send the message of what they see to the brain and the visual brain cells “learn” how to interpret these images.  Over time the brain learns how to fine-tune the images it is receiving and the vision improves.  If the image that is being sent to the brain is blurry then the brain will never learn how to see clearly from that eye.  The important piece in this problem is that the brain cannot “learn” how to see clearly after a certain age (that age is not known for certain).  We do know that the younger the patient is when he/she is treated the better the outcome will be.  So, Amblyopia should be treated as early as possible.

• Causes of Amblyopia
  The most common forms of amblyopia are strabismic and anisometropic. Strabismic Amblyopia occurs when a strabismus is present and the eyes are not aligned. The brain favors one eye over the other and the non-preferred eye is not adequately stimulated and the visual brain cells do not mature normally. Anisometropia refers to the condition when the eyes have an unequal "refractive power". As an example, one eye may be nearsighted and the other farsighted. Because the brain cannot "balance" this difference, it picks the eye that is "easier" to use and develops a preference for this eye only. Other causes of Amblyopia may include include: Cataracts, Ptosis and Trauma.
  
  
• Treatment of Amblyopia
  In most cases Amblyopia is treatable. However, the success of treatment is dependent upon the initial level of vision, the amount of time the vision has been poor and the age of the child. The most important factor in treating Amblyopia is compliance with the treatment protocol. Treatment requires "forcing" the brain to use the non-preferred eye. In most cases this means patching the better seeing eye for some part of the day. Glasses may also be required to "balance" an unequal refractive power between the two eyes. For some patients an eye drop can be used to blur the vision in the better seeing eye.  If a Cataract is present, this may need to be removed before Amblyopia treatment can be started. The initial treatment period may be difficult for the child, as he/she is being made to use their poorer seeing eye. This usually lasts a short period of time, as their vision usually improves rapidly.
  
  
• Prognosis of Children with Amblyopia
  The prognosis for kids with Amblyopia is quite good-if treatment is properly performed.  It cannot be overemphasized that the major reason for failure in the treatment of Amblyopia is poor compliance with the treatment protocol. Remember, Amblyopia can be treated only when a child is young. If it is delayed until the child is older and more understanding, it may be too late!

About Pediatric or Congenital Cataracts

A Cataract is an opacification or clouding of the normal Crystalline Lens.  Cataracts can occur at different ages in children.  The diagnosis of a Congenital Cataract (present at birth) can be made on the first day of life if a red reflex is not obtained in the newborn nursery. Early diagnosis and referral are important since irreversible damage can occur if a congenital cataract is not treated in the first few months of life. Congenital Cataracts can result from problems with the eye itself or from systemic disorders.  Because of this a thorough ocular and systemic evaluation should be performed in any child who presents with a Cataract. A genetic evaluation may be indicated in some cases as well.

• Treatment of Pediatric Cataracts
  If the Cataract is determined to be visually significant, surgery is indicated to remove the involved lens. Once the visual axis is cleared, the child will require optical correction to allow visual rehabilitation. This may include the use of glasses, a contact lens or an intraocular lens implant. Because of the small size of the infant eye, a high power optical correction is necessary, which often cannot be obtained by the use of glasses alone.
  
  Glasses may also not be appropriate in a child following unilateral cataract extraction because of their magnification effect.  This can result in difficulty with clarity of vision as well as problems with the development of binocular vision.  Because of these factors a contact lens is sometimes used.  These contact lenses should not be thought of as a substitute for glasses as they may be in adult patients. They are an absolute necessity for infants with cataracts or an older child with a unilateral Cataract. In some patients an intraocular lens can be implanted. Because of concerns regarding the immaturity and future growth of the infant eye, some surgeons prefer not to implant an intraocular lens in a very young child. Children with bilateral cataracts tend to do better than those with unilateral cataracts. Amblyopia is a major obstacle to the development of good vision in these children. Amblyopia therapy is an important issue in the management of childhood cataracts. A good visual outcome is highly dependent on the compliance with Amblyopia treatment.

About Retinopathy of Prematurity (ROP)

Retinopathy of Prematurity (ROP) describes problems with the development of the blood vessels in the Retina in preterm infants.  ROP describes a spectrum of problems from minimal changes to the periphery of the retina to uncontrolled growth of blood vessels centrally. ROP occurs almost exclusively in preterm infants. Retinal blood vessels begin developing at 16 weeks of gestation and are not fully developed until 40 weeks of gestation.  In infants born prematurely the blood vessels can grow irregularly.  These changes can be transient with small changes to the periphery of the Retina only.  However, they can also involve uncontrolled growth of blood vessels, which in the most severe cases can cause a detachment of the whole Retina.

The risk factors associated with ROP are not fully known, but prematurity and low birth weight are major factors.  Problems such as respiratory distress, bradycardia (low heart rate), heart disease, infection, hypoxia (low oxygen levels), anemia, and the need for blood transfusion are other risk factors. Generally, the lower the birth weight and the more medical problems with the infant, the greater the risk for ROP.

• Treatment and Prognosis of ROP
  In some cases ROP will need to be treated.  This is done using laser or cryotherapy-a form of “freezing” therapy.  In severe cases, surgery to correct a retinal detachment can be required. In more than 90% of infants with ROP there is spontaneous regression of the disease process, with little or no residual effects or visual disability. In less than 10% of infants there is progression toward severe disease.  Despite treatment some of these cases can lead to detachment of the retina, and impairment of vision. Over the course of their lifetime children with ROP are at increased risk for strabismus, amblyopia, nystagmus and refractive errors.

About Learning Disabilities

In general, learning disabilities are a problem of processing and understanding verbal and written language.  Dyslexia is one example of such a disability.  Keep in mind that these learning disabilities are not a problem of intelligence.  It is important to recognize their presence and help children learn to deal with the disability.  Also, do not forget to continue to provide support and encouragement to your child remembering to emphasize the areas where he/she excels. Causes of learning disabilities are not fully understood.  There is probably a genetic component so they can run in families.  There is no good evidence that suggests that learning difficulties are related to a child’s vision or visual system. Treatment of learning disabilities requires a multidisciplinary approach.  Educators, psychologists and physicians should all be involved. We will test the eyes to ensure that there are no refractive errors, strabismus, eye movement problems, or problems with focusing and convergence of the eyes.  Once these areas have been addressed emphasis should be placed on a solid academic program of working to improve your child’s areas of weakness.

About Nasolacrimal Duct Disorders

Tearing in children is a common finding.  There are many different causes of tearing and it is important to have your doctor check your child for some of the more serious problems.  Most often tearing is caused by a blockage of the nasal lacrimal duct (NLD) passageway.  This is a common finding in infants-studies have shown that about 6% of infants are born with a NLD obstruction. The most common cause of an obstruction is from a mucous membrane of the nose, which fails to regress during development.  Other causes of NLD obstructions include irregular development of the lacrimal drainage passageway, infections, trauma, growths and medications. Treatment initially involves massaging the lacrimal system, warm compresses and sometimes antibiotic drops.  If these interventions are unsuccessful, a nasal lacrimal duct probing may be necessary.  At times this procedure can be performed in the office and at times in the operating room.  Some children require the placement of a silicone tube in the nasal lacrimal duct system to keep the passageway open.  This tube remains in place for 6-12 months and can usually be removed in the office.  If this is unsuccessful a balloon cather can be used to dilate the lacrimal system in addition to the silicone tube placement.

Most obstructions will resolve on their own by one year of age.  However, some children have severe symptoms and require intervention before this age. Studies have shown that probing the system is most successful if performed prior to one year of age.  The next most successful group of patients is those undergoing a probing by 2 years of age.  Probing in kids over 2 years of age is also successful but less so than if performed at a younger age.

Baltimore Washington Eye Center provides pediatric and children's eye care for patients from Arbutus, Carney, Clarksville, Columbia, Dundalk, Edgemere, Essex, Ellicott City, Ferndale, Glen Burnie, Kenwood, Laurel, Linthicum, Lutherville, Millersville, Odenton Owings Mills, Reisterstown, Towson, Parkville, Randallstown, Rivera Beach, Pasadena, Severna Park, South Gate, and Woodlawn Maryland. To schedule an appointment for and examination or consultation for pediatric and children's eye care please call us at 800.495.3937.