• CVI
  • Cerebral, Neurological Vision Impairment
  • Cortical Blindness

Cortical Visual Impairment

Cortical visual impairment (CVI) describes a type of partial blindness due to underlying injury to the brain’s visual processing centers. It is also known as cerebral or neurological visual impairment or cortical blindness. 

A child with CVI has eyes that respond to light, a fact that underscores how the condition is not physically related to the structure of the eye itself. Instead, CVI is due to problems interpreting and processing visual information as it is received by the brain. In effect, children with CVI have eyes that can see, but the brain’s visual center has difficulty interpreting what is being seen. For example, they may have trouble recognizing faces (face “blindness”), interpreting facial expressions and drawings, perceiving depth, or distinguishing between background and foreground. They also have a preference for movement and are typically able to see objects better when in motion. They often have better peripheral vision than direct vision, leading to a lack of direct eye contact or “social gaze”.

CVI can be mild or severe and may fluctuate widely day-to-day, even minute-by-minute. Partial recovery is possible over time with treatment.

CVI is caused by any process which damages visual processing centers of the brain, especially to the occipital lobe (the back of the brain). Traumatic brain injury, epilepsy, hydrocephalus, lack of oxygen or blood flow to the brain, encephalitis, brain lesions, meningitis, and metabolic dysfunction are all possible causes of brain damage leading to CVI in young children and infants. CVI often goes undiagnosed, because few medical professionals are aware of it. If your child is exhibiting symptoms, it’s ideal to have both a neurologist and ophthalmologist examine her. A diagnosis of CVI can be made using MRI scans and possibly EEG, after determining that the child’s vision problem is not anatomical. 

The severity of CVI can fluctuate daily, and partial recovery is possible over time with treatment.

Conventional Treatment

Because children’s brains are “plastic” - meaning that they are still developing and maturing - early treatment is crucial to improvement. Encouraging the formation of alternative neural connections can allow vision to improve over time. 

Conventional treatment involves both stimulating visual development and accommodating for disabilities. Children should be functionally assessed to precisely understand their visual impairments so that teachers and therapists can develop appropriate interventions and recommend support services. Assessment includes evaluating eye muscle coordination, the ability to find objects, and the ability to determine what an object is. 

Support

At The Brain Possible, our goal is to empower you to take a holistic approach to your child’s treatment. Below are ways in which you can support several aspects of your child’s recovery; before embarking on any, be sure to discuss them with your trusted health care providers.

Physical

Children with CVI may still have problems with the eyes themselves, and are often near-sighted; they should be evaluated by an ophthalmologist for corrective glasses.

Emotional/Social

Therapy sessions and school can be exhausting for children with CVI, as the brain exerts tremendous energy when visually processing. As such, teachers and caregivers should be sensitive to the child’s fatigue and attention span, and recognize when to take breaks and stop interventions. 

Sensory

Children with CVI may have an over- or under sensitivity to light, poor depth perception and struggle with identifying faces. Parents can help stimulate their child’s visual perception by installing mobiles or coloured moving lights, using touch or sound to attract their attention, presenting visual materials in an uncluttered manner, presenting objects at different angles, and giving the child extra time to respond to an object. 

In a 2006 study on the Rehabilitation of Cortical Visual Impairment In Children, parents were instructed on the necessary stimulation procedures which used light reflex and perception, outline perception and word card exercised performed in the participants’ homes.  The child’s visual function level dictated the visual stimulation program, “with specific stimuli and intensity, frequency, and duration assigned.” You can read more about the study and its findings in our article on types of visual stimulation therapy

Intellectual

Most children with CVI will benefit from extra accommodations at school, such as extended time for visual processing tasks and test-taking. If in public school, a child may qualify for an individualized education play (IEP) under the Individuals with Disabilities Education Act. They may benefit from working with high color-contrast materials and need to forgo pencil on paper and use black ink on white paper instead. Their teachers and caregivers may also help them find auditory learning tools, such as voice-activated readers and study guides, to compensate for their struggles with visual learning. Children with significant visual impairment may benefit from learning braille for reading. 

Nutritional/Environmental

Children with CVI often have a particular color preference (red and yellow are most common), which may provide comfort in the home environment. Color and contrast can help a child move in their surroundings: color-coding, adding contrasting and task lights, and decluttering a room can help a child navigate at home or at school. 

Physiological

A 2014 study showed that stem cell therapy created significant improvement for children with cerebral palsy and CVI. In stem cell therapy, stem cells - usually from bone marrow transplant or umbilical cord blood - are propagated to heal injured tissue.