American Action Fund for Blind Children and Adults
Future Reflections Convention 2022 NOPBC WORKSHOPS
Cortical Visual Impairment: Toward a Deeper Understanding
by Cindy Champagne
From the Editor: Cindy Champagne is a teacher of blind students (TBS) in Louisiana. In this workshop at the NOPBC Conference, she shares basic information about cortical visual impairment and points the way toward the interventions that are needed.
I'm a graduate of the Teacher of Blind Students program at Louisiana Tech University. My son Justin has retinitis pigmentosa, which is an ocular impairment. Through my son I got involved with the NFB. Ever since I made a career switch to teach blind students, I feel I'm walking the path that was intended for me.
During my training the prevailing thought in the field of blindness was that most students with cortical visual impairment (CVI) have additional disabilities, and that they were incapable of learning. People often made comments such as, "Blindness is the least of their problems."
Such thinking runs contrary to the philosophy of the NFB. Regardless of the type or extent of a student's disabilities, we have to assume capacity and competence. Our job as educators and parents is to work hard to remove barriers and give these kids the tools that will help them learn and communicate.
What is CVI?
The American Association of Ophthalmology and Strabismus defines CVI as a decreased visual response due to a neurological problem affecting the visual pathways in the brain. CVI is a brain-based impairment. Typically in these children the ocular structures are fine. There's nothing wrong with the eyeball; there's nothing wrong with the optic nerve. But when visual information reaches the brain, the brain has trouble interpreting what the child sees. When we work with these students it's important to remember that looking is not always seeing.
Like low vision caused by an ocular impairment, CVI is a permanent condition. It never goes away. The brain has sustained permanent damage to the visual pathways. CVI is a disability of visual access, and it's defined by deficits in typical visual function. We have to look at how the child's vision functions, just as we do when we conduct a functional vision assessment on a child with an ocular visual impairment.
Unlike children with ocular impairments, our students with CVI can improve their visual functioning by learning to use their sight. The term neuroplasticity means that the brain is capable of rewiring and healing itself. The more children with CVI use their vision, the more their functional vision will improve. They still have a visual impairment, but they can learn how their vision functions in order to use it more effectively.
Prevalence of CVI
CVI is now the leading cause of visual impairment in the industrialized countries. According to the 2021 Babies Count data, CVI is the leading cause of visual impairment in the birth to five population. Thirty per cent of children identified as having a visual impairment in this age group have been diagnosed with CVI. The National Institutes of Health website published a study demonstrating that CVI occurs in 10.5 percent of all children with developmental disabilities.
Scotland has one of the world's most sophisticated systems for reporting health information on children. Approximately 0.7 percent of all the children in Scotland have been diagnosed with CVI. One study looked at a group of children who had been red-flagged as having learning disabilities. These kids struggled in school and were going through the intervention process. The education team tried various strategies and modifications to build in the scaffolding that would help the children learn. It turned out that 31 percent of these children had CVI-related visual behaviors. The children in the study never had been identified before as having a visual impairment.
Here in the States we are very careful to screen children for visual acuity. However, we miss issues around visual processing. Screening for visual processing issues is critical for our kids who have multiple disabilities. Often they're not verbal, so they can't tell us what they see.
In one study, among children who were admitted to the NICU [neonatal intensive care unit] at birth, 51.6 percent were found to have CVI related visual behaviors. A small study of kids with autism found that 100 percent of them had optic ataxia. It's being misdiagnosed as a fine-motor issue. A 2021 study of kids with Down syndrome showed that 38.3 percent of them had undiagnosed CVI. These studies give an idea how widespread our undiagnosed population of kids with CVI really is.
Anything that causes an insult to the brain can damage the visual pathways. Asphyxia (lack of oxygen to the brain); periventricular leukomalasia (PLM), which has to do with white matter degeneration in the brain, often found among premies; cerebrovascular accidents; and trauma, including shaken baby syndrome—all of these conditions can damage the brain's visual pathways.
Many children with CVI had seizures and infantile spasms. Some who have had severe seizures present as functionally blind. Kids whose seizures were controlled at an early age generally have higher visual functioning. CVI may not be noticed in these children until they begin to struggle in school.
CVI is not always related to brain trauma. Kids with congenital brain abnormalities such as septo-optic dysplasia (SOD) and optic-nerve hyperplasia (ONH) have a wide spectrum of visual disabilities that may include CVI. CVI also occurs in children with certain chromosomal diagnoses. It can be part of the way the brain is formed.
Diagnosing CVI
To make a diagnosis, most doctors want to see the place in the brain where things aren't working properly. However, the causes of CVI don't always appear on an MRI. Medical professionals can make a diagnosis of CVI if the patient meets these four criteria:
- The child is at least six months of age.
- The vision loss cannot be explained through an eye examination or a known ocular impairment.
- The child has a medical diagnosis that affects the brain.
- The child shows at least one of the visual behaviors characteristic of CVI.
The Visual Behaviors of CVI
Dr. Christine Roman quantified a set of behaviors that are typical of children with CVI. She was a COMS with both TVI and orientation and mobility training, and she felt called to work with kids with multiple disabilities and health impairments. She began to notice a pattern of visual behaviors in these children, and she was able to quantify it through her studies.
Color Preferences: The first thing Dr. Roman noted was color preference. Typically, kids with CVI are drawn to red or yellow. They prefer highly saturated, very bright colors, especially when they're presented with contrast. Right now twelve kids on my roster have CVI. Some of them prefer green. They don't visually orient to red or yellow; they orient to green right now. It's important for me to know that! I'm not going to put a red Mardi Gras curtain on a light box to try to get them to use their vision right now. I'm going to use green Mardi Gras beads and green pompoms.
Visual Latency: The visual responses of children with CVI tend to be delayed. If you don't give them time, you might assume that the child sees nothing. The child needs a chance to notice that an object is there. Eventually the child will attend to the object, if the object is appropriate.
A Need for Movement: Children with CVI have a huge need for movement. They may be attracted to moving objects such as ceiling fans.
Two of my students are developing typically, apart from their vision. When they started to crawl, they'd be looking for a particular toy. They knew it was there, but they couldn't pick it out from the background. They'd get on all fours and start to rock. In that way they gave the property of movement to a stationary object. They stopped rocking as soon as they picked up the toy. In these children rocking is not a stimming behavior as we might suspect. It's a matter of the way their vision functions.
The Challenge of Complexity: Complexity is a big issue for kids with CVI. Kids with CVI have trouble using their auditory and tactile channels at the same time as their visual channel because using their vision is a difficult process. They have to work at seeing.
Visual Field Preferences: All children with CVI have visual field preferences. A typically sighted person has central vision straight ahead, left peripheral and right peripheral fields, and upper and lower fields. Kids who appear to be functionally blind typically don't do well in the central field. Typically they prefer far left or far right. Occupational therapists and physical therapists tend to present objects in the central field, where the child can't see them. It's important to tease out which field works best, left or right.
Eventually the upper field may start to resolve, but for most kids with CVI, the lower field never resolves. Issues with the lower field present challenges for orientation and mobility. These kids trip because they can't see changes in height. It's especially difficult when they're in a complex sensory environment.
A Need for Light: A lot of kids with CVI will gaze out windows and stare at overhead lights. Even when their functional vision begins to resolve a bit, they stare at lights when they're tired or sick. They engage their visual system through this behavior.
In the Ophthalmologist's Office
Ophthalmologists and optometrists work in a clinical setting with perfect lighting. They look at acuity and refractive error, trying to determine whether a child needs glasses. They tend to miss the kids with CVI who function with usable vision and don't present as blind.
Parents often face dismissal from the medical community. Ophthalmologists say, "There's nothing wrong with your child's eyes." This is the attitude we're trying to change. Often, related service providers are some of the first to notice that their patient is not using their vision in a functional way. Then they come to us, the educational community, and say, "Hey, can you help my child/student? My kid can't see!"
Currently the only ICD.10 [International Classification of Diagnoses] code that doctors can use for a diagnosis of cerebral cortical visual impairment is cortical blindness. Cortical blindness is a very old term. It was developed for soldiers coming back after World War I and World War II who were functionally blind due to traumatic brain injury. That's the code that is still being used! If your child is using their vision for some functions such as reaching and touching, but they can't interpret what they see, it's understandable that a doctor might not say they're blind. They will use the term "low vision," but it is very hard to get them to put "legally blind" on an eye report, especially when they don't see damage in the visual pathway on the MRI. We need to educate the professionals.
As a TVI I work closely with several ophthalmologists in town. I go to appointments with kids and their families, saying, "Okay, Doctor, this is what I'm seeing." The doctors are starting to understand that we're seeing things from a functional visual standpoint, not necessarily an acuity standpoint.
As TVIs we can do a better job of building bridges between families and eye doctors. If you build a personal relationship with a doctor, they will trust what you say. With a couple of doctors I'm now able to send in a functional vision assessment. I can say, "I'm not seeing any sign of an ocular impairment, but this is what I'm seeing." Unless we identify the child as being visually impaired, they can't get the help they need when they get to school. We need the doctor to say, "Okay, here's your diagnosis, put them on the registry as a student with a visual impairment." We can provide a lot of help to families, but we can't do anything without a diagnosis!
Helping Children with CVI
CVI is a visual impairment, which means it is covered under IDEA (the Individuals with Disabilities Education Act). Any impairment in vision that adversely affects a child's educational performance meets the criterion for the exceptionality of visual impairment. It doesn't matter that it's not an ocular impairment. Kids with CVI are unable to access typical materials in a typical classroom. CVI is a disability of visual access just like ocular low vision and blindness.
We are missing many of the kids we should be serving. Visual impairment may not be their primary exceptionality. We know about the neuroplasticity of the brain—the more a child uses their vision, the more they teach their brain, and their functional vision improves. However, it may not improve enough for the child to keep up with sighted peers in a typical classroom.
Under IDEA Braille instruction is required for a child with a visual impairment unless the IEP determines that it's inappropriate for that particular child. Braille may not be appropriate for some kids, but we need to keep the tools of blindness on the table.
Because kids with CVI have a visual impairment, they are entitled to instruction from a qualified TVI, and to instruction in all nine areas of the expanded core curriculum (ECC) to enhance their quality of life. The days are over for us to say, "We can't teach them the skills of blindness! Blindness is the least of their problems!"
For about half of the kids with CVI whom I work with, tactile learning is not an option. They don't have independent use of their hands. When we learn how they use their vision we may be able to make it possible for them to communicate. Maybe they can use an eye gaze device. We can adapt augmentative and alternative communication (AAC) devices so they can access them visually. Such a device can allow them to express their needs and wants independently. We have to do whatever we can to unlock the potential in these kids.
As TVIs we have an ethical responsibility to be the experts in vision on our teams. The service delivery model may look different for kids with CVI, but we can't say these kids are not our problem. It is unfair to say that helping these kids takes time away from our academic Braille readers. All of our students deserve the best help we can give them. Kids with severe and profound disabilities have the potential to learn, to have some degree of independence and communication.
The Need for Advocacy
It breaks my heart to hear stories of parents who have a TVI on their team as a "consult." The TVI pops into the profound/severe classroom for fifteen minutes and says, "How're you doing? Anything I can do for you?" Sometimes the TVI comes during nap time and never sees the child interacting in the classroom.
I know it's overwhelming to think about the population we could be serving. But if we don't identify the true need, we won't know how many more people we need in the profession. We won't be able to go to the people who control the funds and say, "This is what these kids need and deserve."
I urge us as TVIs to keep advocating along with parents for a proper diagnosis. It is a lot easier to get services with a diagnosis! Request a functional vision assessment if CVI is suspected. You should expect a report. The assessment tool should be CVI geared and CVI informed. Our standard functional vision assessments for kids with ocular impairments are not appropriate for our students with CVI. We have to understand how these kids use their vision.
A major reason we're seeing more kids diagnosed with CVI is the research being conducted by dedicated, informed parents. As members of the NFB we should give these parents our empathy and support. In the NFB we fight for Braille for our blind kids. We fight for accommodations and modifications, and we fight to ensure there are certified, qualified TVIs to serve them. We need to fight just as hard to get help for our kids with CVI. I'll say it again and again: we're better together, not apart. We must not see helping kids with CVI as a threat to our kids who have ocular impairments. We can serve all of our kids! We don't need to limit our services and concerns to kids with ocular impairment!
CVI and the ECC
As TVIs we need to perform ongoing functional vision and learning media assessments. We know that functional vision improves. If we only evaluate the functional vision of these kids every three years, when they come up for their re-evaluation, we'll miss the changes. If we see no improvement, we need to evaluate how we're accommodating and modifying to support visual access. All of our tools need to be available to these kids—the tactile, the auditory, and the visual tools. It's our responsibility to be the expert on the team who can help the child develop those tools and also support their IEP team.
It's also our responsibility to give these students an orientation and mobility screening and make a referral for O&M training. The child's lower visual field will remain atypical for life. In a complex sensory environment people with CVI have a hard time orienting and navigating. They cannot access the visual channel in those situations, so they may need to be situational cane users.
We have to do ongoing assessment of needs under the Expanded Core Curriculum. We should do it annually, prior to the new IEP. Once we've done these assessments and know what the child's needs are, we need to do a data-driven analysis to determine our service-level recommendations. We can't say, "I only have time to give fifteen minutes a month." We should ask, "What does this child need?" I highly recommend the Visual Impairment Scale of Service Intensity from the Texas School for the Blind and Visually Impaired. You do the needs assessment and plug in your data to find out the child's needs for direct instruction and what the team needs to do in each area.
Each child is different, and we need to do a lot of collaborative instruction. I do a lot of training with the team that works with my students who have additional disabilities. I work with the occupational therapists, physical therapists, and speech therapists. Every member of the team must be aware of CVI and how each individual child uses their vision. I find that other professionals are starting to call us in to do vision assessments on some of the kids they work with when they suspect that CVI may be an issue. We can't work in silos. We all need to work together.
Resources
https://www.perkins.org/cvi-now/ by The CVI Center at Perkins
https://pcvis.vision/ This is the website of the Pediatric Cortical Visual Impairment Society, started by parents, ophthalmologists, and optometrists
https://littlebearsees.org/ An organization begun by one of the first families that brought awareness and attention to CVI.