The brain injury caused by an oxygen-depriving event can often cause impairment in a child’s vision and/or hearing. Generally, newborn babies are screened at birth for sensory impairment issues and then are screened periodically throughout their development. If parents have concerns about hearing or vision, they can speak to their child’s pediatrician about evaluations and interventions (such as glasses or a hearing aid). If the child needs assistance, they can then be referred to an ophthalmologist (for vision evaluation and care) or an audiologist (for hearing evaluation and care). These medical professionals can provide recommendations regarding what kind of interventions the child will need – sometimes this may involve glasses or a hearing aid, though there are certain circumstances in which surgical intervention may be appropriate.
Many children with HIE-related cerebral palsy are known to have vision impairments, which can include acuity loss, field loss, oculomotor problems, sensory processing difficulties, and hearing loss. Up to 13% of children with CP have hearing loss.
Hearing loss associated with HIE can fall into one of two categories: sensorineural or conductive. Sensorineural hearing loss is more difficult to treat because it means that the nerves that transmit signals to the brain are damaged. This can be remedied with a combination of a cochlear implant and hearing aid. The cochlear implant bypasses the injured nerves entirely, acting as a conduit for sound. Conductive hearing loss is simpler to treat, as it tends to involve damage to the physical portions of the middle ear rather than the nerves themselves. This damage is often caused by inflammation and fluid buildup. When this inflammation is addressed, the problem often decreases in severity. For severe cases or recurrent conductive hearing loss, hearing aids and surgery are also options.
What Signs Should Parents Look For If They Are Concerned About Their Child’s Hearing or Vision?
Signs of Visual Impairment
- Difficulties with focusing while looking at objects
- Blurred vision
- Field vision loss
- Problems making fast eye movement
- Trouble recognizing familiar faces
- Covering eyes while trying to read
- Slow speech and language development skills
- Moving the head while reading (as opposed to moving eyes)
- Underdeveloped hand/eye coordination
- Eye squinting when reading or focusing on objects
- Holding books or other materials close to the eyes when reading
- Frequent headaches
Signs of Hearing Impairment
- (In babies) Not reacting to human speech
- (In babies) Not being calmed by what should be a familiar voice
- (In babies) Not startling or waking up at loud noises
- Lack of response to simple requests
- Delays in language acquisition and speech
- Does not show signs of listening to stories or songs
- Not repeating sounds or words
- Does not respond correctly to questions
Strabismus Associated with Hypoxic-Ischemic Encephalopathy (HIE)
One sign of a visual disturbance is called ‘strabismus,’ a term that means a child’s eyes are improperly aligned, making them turn in different directions. When this happens, the set of muscles around one eye may work harder than the other. Because the eye muscles do not work together, the brain may have difficulty combining the visual images from the two eyes. This can mean that the individual may be more prone to an awkward gait, accidents or collisions with their surroundings because their eyes are sending inaccurate images of their surroundings to the brain. An ophthalmologist may be able to correct strabismus and ensure the eyes can work together properly.
When Should a Child be Referred Early to a Hearing or Vision Specialist?
There are certain HIE-associated diagnoses that indicate that a child should be referred to an ophthalmologist or audiologist early. These include:
Indications for Early Referral to an Ophthalmologist
- If a child has Stage III HIE
- If a child has Stage II HIE with either an abnormal neurological examination or reduced visual examination at discharge from the hospital
- If a child has an HIE-associated stroke
Indications for Early Referral to an Audiologist
- If a child has intrapartum asphyxia, they should be tested for sensorineural hearing loss after birth and before they are discharged from the hospital.
- If the child has persistent pulmonary hypertension (high blood pressure) along with HIE, the child may be at risk for late-onset hearing loss and should be tested repeatedly throughout childhood.
Vision and hearing are critical for a child’s development, as they are two of the most important sense through which a child perceives the world. Hearing is especially critical for language acquisition, making early intervention an important component of ensuring the child will be able to interact with family, friends, peers and teachers. If a child has some delays in language, speech or social development, hearing aids and glasses – in conjunction with intensive speech/language therapy, specialized educational interventions, and behavioral/social therapies – can help mitigate delays.
Additional Information on Visual Impairment
- Research: Visual Problems as a Result of Brain Damage in Children
- Visual Impairment and Cerebral Palsy
- Vision Screening in Young Children
Additional Information on Hearing Impairment
- Hearing Loss and Cerebral Palsy
- Checking for Hearing Loss in Young Children
- The Importance of Early Hearing
- CDC: Hearing Loss