De Morsier's Syndrome
What Is De Morsier’s Syndrome?
De Morsier’s syndrome is a rare disorder, present at birth, in which the optic nerve is underdeveloped (called “optic nerve hypoplasia” or “ONH”). The pituitary gland does not function properly, and often a portion of brain tissue is not formed. De Morsier's Syndrome, also known as septo-optic dysplasia, may cause visual impairment or blindness in one or both eyes and is also often accompanied by nystagmus (involuntary darting of the eyes) and various other symptoms. Some children with De Morsier's Syndrome have normal intelligence, while others may have a developmental delay or learning disability.
Vision loss is not progressive; in fact, vision may improve slightly over time, and nystagmus may decrease.
How Is De Morsier’s Diagnosed?
Parents may notice a lack of eye contact and visual responsiveness and will have their child assessed by an ophthalmologist; alternatively, the child will visit an ophthalmologist for a routine eye exam. When the child’s eyes are dilated, the ophthalmologist will note that the optic nerve is small and/or pale, and will diagnose optic nerve hypoplasia. Additional tests such as an MRI and bloodwork will be run to diagnose any brain and hormone abnormalities.
Are There Treatments for De Morsier’s?
At present, there is no treatment for condition of the optic nerve. However, if your child has a more severe visual impairment in one eye, the ophthalmologist may recommend patching (occluding) the better eye in order to encourage the weaker eye’s use. A doctor will also prescribe medication to control hormone levels.
How Would You Describe the Eyesight of One with De Morsier’s and How Will My Child Function with It?
While it is possible to have typical vision or total blindness with De Morsier’s, children and adults with ONH commonly experience poor visual acuity (blurriness) which is not correctable with glasses, peripheral field loss (tunnel vision), as well as sensitivity to bright light and glare (photophobia).
A child with poor visual acuity may have difficulty recognizing faces and facial expressions, as well as accessing near and detailed information. If this is the case, your child may benefit increased room and task lighting; assistive technology to more easily write, read, use the computer, and access information; and techniques and additional accommodations to perform activities with limited vision.
A child with loss of peripheral vision has some degree of “tunnel vision,” making it difficult to gather comprehensive visual information in an environment. He or she will benefit from learning visual efficiency skills such as scanning an environment in an organized manner. Additionally, such a child is likely to bump into side-lying and low-lying obstacles; he or she should learn Orientation and Mobility (travel) techniques, such as the use of a cane, to avoid obstacles.
A person with photophobia may benefit from specialized sunglasses (amber-tinted lenses), use of a brimmed hat while outdoors, and shutting blinds while indoors if glare is present.
If your child is totally blind, he or she must be taught to complete tasks without use of vision. Your child may be taught braille, screen-reading software to use the computer, and techniques for performing life skills and academic tasks.
Your child’s Teacher of Students with Visual Impairments should perform a Functional Vision Assessment to determine how your child uses his or her vision in everyday life and a Learning Media Assessment to determine which senses your child primarily uses to get information from the environment. These assessments, along with an Orientation and Mobility Assessment conducted by a mobility specialist, will give the team information needed to make specific recommendations for your child to best access learning material and his or her environment.
Resources for Families of Children with De Morsier’s
- Septo-Optic Dysplasia by Genetics Home Reference
- Optic Nerve Hypoplasia by the American Association for Pediatric Ophthalmology and Strabismus
- Optic Nerve Hypoplasia by the Children’s Hospital Los Angeles
- Optic Nerve Hypoplasia reprinted from the Blind Babies Foundation on the Texas School for the Blind and Visually Impaired website