Living with Optic Nerve Hypoplasia
When my daughter Serina was born on November 12, 2010. She was perfect with 10 fingers and 10 toes and had beautiful auburn hair. What I did not know was that she was born with an eye condition called Optic Nerve Hypoplasia or ONH. This, of course, was not apparent right away. She would sleep past her feeding time and was not sucking very well. I tried breast feeding but it was hard to tell if she was getting enough milk, the nurses would bottle feed her to supplement her food intake. She would not be able to leave the hospital unless she was eating at least 2 ozs every feeding and had a normal bowel movement. She was also jaundiced and not very responsive to stimuli. She would have to spend the next few days under the UV light until her bilirubin numbers went down. And finally, she did not pass her hearing test! This all within just a few days of her birth, not even a week old. The nursing staff assured me this would all pass and she would be just fine. At her first doctor’s appointment her pediatrician said she was normal physically but did not know why she failed her hearing test, not interested in eating or why she wanted to sleep so much. Her bilirubin dropped a little before she left the hospital but he still wanted me to expose her to sunlight as much as possible. Her lethargic state, weak sucking ability and the shaking of her eyes (which she was later diagnosed with nystagmus) was something her pediatrician was concerned about, so he referred me to a string of pediatric specialists that included an ophthalmologist, neurologist, ENT, genetics and endocrinologist. He also referred me to the Blake Foundation and Arizona School for the Deaf and Blind. He encouraged me to see the eye doctor first and she was immediately diagnosed with ONH, an eye condition that causes blindness. In fact, it is the leading cause of blindness today. He explained that during fetal development the optic nerve failed to develop completely and did not create enough nerve endings in the brain to detect light and allow for normal vision. He was 100% sure of her diagnosis and that both eyes were affected. What he could not tell me was if she was able to see or not because he did not know the severity yet. She would be considered blind by definition but each case is different. The severity depends on the number of nerves affected in that some children can see normally, some blurry and some not at all. This would have to be determined as she got older and how she reacted to various stimuli. He encouraged me to get in touch with ASDB and expose her to stimuli such as bright light, colors and contrasting black and white figures. Oh and one last thing, he said “this condition is permanent and could not be corrected by surgery”, it was part of the brain and she was just born that way! Plus, she may also have other brain abnormalities, hormonal and developmental issues, and I should immediately see a neurologist and endocrinologist.
Wow, this made my heart sink! My perfectly healthy beautiful baby girl is blind! What am I going to do?
This would be the first of the many Doctor’s appointments, MRIs and surgeries she would endure before she turned two years old. Luckily It turns out that she did not have any structural brain abnormalities but she did have one hormonal issue with her thyroid gland called hypothyroidism, she was also hypotonic (had low muscle tone) which could affect her walking and would be developmentally delayed. Her hearing never got any better and she continued to fail her hearing tests. She was diagnosed with a slight hearing loss Sensor Neural Hearing Loss, with her left ear being worse than her right. She will have to use hearing aids in both ears for the rest of her life. Despite all of this, she is the best thing that ever happened to me! She is very smart, ambitious and a very lovable little girl. She is perfect in every way and I feel very blessed to have her in my life. I am certain her condition will not stop her from living a normal fulfilling life. Optic Nerve Hypoplasia is the most common form of blindness and can be accompanied by various hormonal and neurological problems. These problems stemming from the anatomy and physiology of her brain. For example, the abnormal function of the pituitary gland, which is an endocrine gland that controls certain hormones we need to function properly, affects her thyroid by not producing enough thyroid stimulating hormone causing hypothyroidism affecting her thirst center and metabolism. She is constantly thirsty and can’t get enough to drink. She will have to take medication for this, which may get better in time but in the meantime it needs to be controlled and I have to monitor her fluid intake.
What Is Optic Nerve Hypoplasia (ONH)?
Optic nerve hypoplasia mainly affects the vision, it is the underdevelopment or absence of the optic nerve combined with possible brain and endocrine abnormalities. The optic nerve is a collection of thousands of nerve fibers that transmit visual signals from the eye to the brain, and develops and grows during intrauterine life. ONH is also known as septo-optic dysplasia. An ophthalmologist can diagnose optic nerve hypoplasia easily, by looking inside the eye with an ophthalmoscope to see if the front surface of the optic nerve appears smaller than normal. In some cases of ONH, children will have a nystagmus. The eyes may seem to move around with no real pattern or purpose. This occurs because the eyes are not able to focus enough to hold still. Optic nerve hypoplasia can affect one or both eyes, if both eyes are affected they may be affected to different degrees. Children with bilateral optic nerve hypoplasia typically present in infancy with poor vision and nystagmus. Children with one hypoplastic nerve, is typically turning in of the affected eye. Someone with this condition will undergo a number of eye examinations to determine his or her vision. The younger the child, the more difficult it is to tell the amount of vision present. It takes a number of years to be able to tell what a child's vision will be like. The vision does not worsen over time from ONH, however, it may improve over time. Vision impairment ranges from completely blind to very good vision and it can occur in one or both eyes. Most children with ONH experience some improvement in their vision during their early childhood years.
Although optic nerve hypoplasia has been associated with maternal diabetes, maternal alcohol and drug abuse, maternal use of anti-epileptic drugs, and young maternal age (20 years of age or less), most cases of ONH have no clear identifiable cause. There are no known racial or socioeconomic factors in the development of ONH, nor is there a known association with
exposure to pesticides. To this day there is no cure for ONH. There is no medical or surgical treatment, however, occlusion of the better seeing eye may improve vision in the other eye. In my daughter's case her left eye is the weaker eye, because she prefers to use her right eye her doctor has ordered me to patch her right eye to give her left eye a chance to be used, otherwise she will eventually lose all site in that eye, I will have to do this until she turns five years old. Children with significant vision loss in both eyes may benefit from early supportive attention by low vision specialists.
exposure to pesticides. To this day there is no cure for ONH. There is no medical or surgical treatment, however, occlusion of the better seeing eye may improve vision in the other eye. In my daughter's case her left eye is the weaker eye, because she prefers to use her right eye her doctor has ordered me to patch her right eye to give her left eye a chance to be used, otherwise she will eventually lose all site in that eye, I will have to do this until she turns five years old. Children with significant vision loss in both eyes may benefit from early supportive attention by low vision specialists.
This image is of the hypothalamus, a portion of the brain that contains small nuclei with a variety of functions, including hormone production, controlling body temperature, hunger & thirst, fatigue, and sleep. In children with ONH, it is often not functioning properly.
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This image is an MRI showing the midline of he brain from the side view. They grey crescent shape in the middle is the corpus callosum
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Visual and Behavioral Characteristics
- The child's vision is characterized by a lack of detail (depressed field), but this lack of detail is not comparable to the blurred reduction in vision when a person removes her glasses.
- In certain cases of ONH a specific field defect occurs. Children may not be aware of people or objects in the periphery.
- Children with ONH may be unable to locate objects in space precisely due to a lack of depth perception.
- Some children with ONH have mild photophobia. These children may squint, lower their head, avoid light by turning away, or resist participating in outdoor activities.
- When one eye is affected more than the other, an ophthalmologist may recommend a trial of patching the stronger eye, since the visual loss may be due to amblyopia.
- Some feeding issues are associated with hormonal problems. Lack of interest in eating may be due to absent or diminished sense of smell and taste. Children with ONH may have very restricted food preferences. Some children exhibit excessive lip smacking while eating.