If your child is at least 3 months old and doesn’t follow an object with their eyes or doesn’t recognize familiar faces, they may have an issue with their eyes that, in many cases, may be helped with glasses or other visual aids. In other cases, visual symptoms could be a sign of cortical visual impairment (CVI), also known as cerebral visual impairment. This complex neurological condition impacts children’s vision starting at birth, and can be a sign of a neurological disorder.
Symptoms can look different for each child. Savannah, who is 12 years old, takes in her world using her sense of hearing first, followed by touch and vision. “It’s very hard for Savannah to visually process and understand her visual world,” explains her mother, Lacey Smith, M.Ed., TVI. Smith is the community manager at the CVI Center at Perkins School for the Blind, where her daughter is a student. “She has difficulty integrating all her senses at once.” For example, Savannah, who has also an extremely rare genetic condition known as Ogden syndrome, is very in tune with sounds. When an instrument is played within arm’s reach, she reaches out to touch it instead of using her eyes to search for the source of the sound.
Because CVI is relatively rare, it’s often misdiagnosed or left undiagnosed, and, there isn’t a cure or a scientifically backed treatment that addresses the root cause. However, a number of promising practices can be very effective in helping children make progress in their functional vision, says Christopher Russell, M.S., Ed., TVI, a teacher of students with visual impairments in the New York City Department of Education.
What Is CVI?
While you might associate what you see with your eyes, your brain is actually where much of your vision happens. In order to see the world in front of you, the brain processes information it receives through light that enters your cornea and hits the retina in the back of your eye. The retina then turns this light into electrical signals, which travel through the eye’s optic nerve to the brain’s visual cortex. There, brain cells (called neurons) process and interpret this information, translating it into an image you recognize.
CVI occurs when this process isn’t functioning properly.
Children with typical vision can learn simply by observing what’s in front of them. That’s not the case for children with CVI, whose vision impairment means they can’t learn “incidentally” like others do, explains Christine Roman-Lantzy, Ph.D., who is an internationally recognized CVI expert, and actually defined it in 2007. “They can see something, but maybe they can’t interpret it,” she says. Dr. Roman-Lantzy estimates that 30-40% of children with visual impairments have CVI.
Symptoms associated with CVI often result in a misdiagnosis of autism or ADD. Instead, research shows that a high percentage of children with CVI actually have a neurological genetic disorder, cerebral palsy, and/or epilepsy, often alongside developmental delays. The National Institutes of Health (NIH) estimates that 10.5 percent of all kids with developmental disabilities have CVI.
Despite these numbers, the condition is frequently missed: Experts believe that only 20% of CVI cases are correctly diagnosed. In children with multiple complex conditions, understanding or even recognizing differences in vision may not be a top priority, says Russell.
A proper diagnosis is critical since it helps your child get referred to the right support and services. “The cost to society of missed diagnoses is astronomical, especially when treating a child for the autism they don’t have,” she says. “A child may need constant care, and as an adult, may never learn how to function independently. No one ever thought to address their visual needs.”
Signs of CVI
Children with CVI may exhibit certain behaviors. The Perkins School points to the following:
- Trouble with direct eye contact and social gaze: Your child doesn’t always seem to recognize you or identify features that make you “you.”
- Clumsiness: Your baby struggles to accurately reach for and grab objects. Older children may frequently trip and fall.
- Trouble sorting or picking things out in a crowd: Your child has trouble recognizing objects in clutter.
- Fatigue in everyday situations: Your child may seem quickly overwhelmed or tired in noisy and cluttered environments, even if they’re otherwise healthy and well-rested because using vision to process the world is hard work for children with CVI.
Dr. Roman-Lantzy’s internationally recognized “The 10 Characteristics of CVI” notes that children with CVI may have visual preferences that attract their attention, such as:
- Colors: Your child seems to notice a certain color more than others.
- Movement: For example, your child can’t pay attention in class when other kids are moving around.
- Light: Your child may be drawn to lights (such as lamps or phones). Or, they may seem to turn away from sources of light and get tired quickly when looking at screens.
- Nearby objects: Your child may pay more attention to things within reach, and they might have problems with distance viewing, Dr. Roman-Lantzy says.
How CVI Is Diagnosed
Russell says CVI is generally diagnosed between birth and age 21, “although it can be diagnosed at any age.” Because CVI is relatively unknown in the medical community, doctors often miss the diagnosis. “It would be much easier if everyone had the same symptoms and same problems,” says optometrist Nicole Ross, O.D., an associate professor of optometry at the New England College of Optometry, in Massachusetts.
As with any chronic health condition, getting the right diagnosis is important. “The earlier a family knows, the earlier meaningful interventions can start,” Russell says.
No one test diagnoses CVI. Diagnosis may require seeing several other specialists, such as a pediatric ophthalmologist, neuro-ophthalmologist, optometrist, and neurologist, who will take a comprehensive medical history and perform exams.
Your child should first visit an ophthalmologist, who can perform a comprehensive eye exam to determine whether the symptoms are due to a need for glasses and/or if other eye conditions are contributing to your child’s vision difficulties.
If the results don’t explain the symptoms, your next step is to see a CVI practitioner. Many times, your child may appear to have good vision (i.e., 20/20 vision), but may still have visual difficulties caused by CVI. This is because typical eye exams don’t show how the brain is struggling to process visual information, Russell says, and MRIs can’t show how CVI functionally impacts vision.
As the CVI practitioner oversees a functional vision assessment, they’ll consider your child’s medical, developmental, and educational history, including information gained from speaking with you, as well as potentially with teachers, therapists, and, when applicable, your child.
Why does CVI Happen?
CVI often occurs when the brain is deprived of blood flow and oxygen shortly before, during or after birth, such as due to conditions such as hypoxic-ischemic encephalopathy (HIE), periventricular leukomalacia, or stroke.
CVI can also be a symptom within hundreds of various genetic disorders, says Russell. He adds that there’s very little research connecting these conditions with CVI, but practitioners have noticed links in the children they see.
If your child’s doctor hasn’t identified a cause for CVI, especially if your child has other signs of a genetic disease, such as significant delays in meeting milestones, they may recommend genetic testing.
Interventions to Help Your Child
If your child has been diagnosed with CVI, your child’s CVI team will use various exercises to train your child’s brain to understand the signals coming from their eyes. Your child’s vision will improve over time with this training, “but CVI never completely resolves on its own,” given it’s caused by other factors, says Russell. Instead, he explains, personalized interventions should give your child opportunities “to learn to make sense of what they are seeing and interpret that visually.”
Your child’s practitioner will also assess your child to understand which accommodations and adaptations may support your child, in and out of the home. They’ll consider several factors, including the child’s spatial awareness and the overall impact of CVI.
Your larger care team members will each play a role. Those individuals may include:
- Teacher of the visually impaired, or special education teacher, who instructs children with visual impairments and blindness
- Occupational therapist, who assesses your child’s vision abilities and finds individualized modifications in their routines or environment to help them participate in everyday activities
- Orientation and mobility specialist, who teaches movement and orientation skills to help your child navigate their environment safely and confidently
- Physical therapist, who builds your child’s movement and gross motor skills with visual, balance, and mobility training
- Speech-language therapist, who helps improve your child’s language and communication skills, including for non-verbal children, and supports feeding issues associated with visual impairments
- Technology specialist, who recommends appropriate assistive technology (equipment, such as switches or tablets) and helps your child to use it
If your child is in school, they’ll receive an individualized education plan (IEP), so that the school curriculum and materials are accessible. Assistive technologies can also help. For example, Savannah uses the AbleNet BIGmack switch, which is a button that can play pre-recorded words when you press it, to make it possible to communicate.
Getting the right tools and care team in place can take conviction and persistence, Russell says. If any person with your care team is unable to offer meaningful treatments for your child, it’s time to seek a new practitioner.
Hope for Children with CVI
A lot of burgeoning research is giving the CVI community hope. The National Eye Institute at the National Institutes of Health made CVI a priority in its 2021 Strategic Plan, says Dr. Roman-Lantzy. Researchers there are creating a virtual reality tool with brain imaging to help understand the CVI vision process, and they’re developing new ways to test vision in infants and young children. Furthermore, the American Foundation for the Blind invites research for its 2024 Special Issue on Evidence-Based Interventions for CVI.
Meanwhile, for Lacey Smith, every day brings opportunities. “Savannah is my complex little beauty who I continue to learn from and who pushes me to be the best version of myself,” she says. “My hope for Savannah and all children with complex needs is that they always see the light and joy they bring to those who embrace them.”
References and Further Reading