A Brain Injury can occur in a second. A sports injury, a motor vehicle accident, or a fall can cause a head injury. This is termed a *Traumatic Brain Injury.* A *concussion* due to a school sports injury is a mild brain injury. Concussions can have an additive effect and several concussions can lead to major difficulties. Often what appears to be relatively minor or not obvious, can actually cause severe problems.
Vision and Brain Injury
Vision is the most important way we bring in information into the brain and then process that information. Injury to the brain can disrupt the visual process and then interferes with how information is taken in and processed.
These problems can include:
Vision can be compromised as a result of a neurological disorder such as a stroke, a brain tumor or Multiple Sclerosis. These are termed *Acquired Brain Injuries*.
Neuro-Optometric Rehabilitation at our vision center in Orange County and surrounding areas, CA is a specialized Vision Therapy program for those who have suffered a brain
injury. It effectively treats the visual problems of brain injury such as double vision, difficulty tracking, physically focusing, or maintaining attention. Once these vision problems are addressed, the effects of the injury are eliminated or reduced. The individual is then able to gain more from other therapies, such as occupational therapy, physical therapy, cognitive therapy, etc. If vision is not addressed, it is often difficult to recover or to reach greater potential.
When someone has a Traumatic Brain Injury (for example a car crash or a bad fall) or an Acquired Brain Injury (stroke or brain tumor), it is common to then have problems with vision. Making sense of what you see is one of the most important brain functions. Neuro-Optometrists help people individuals to solve the vision problems brought about by that brain injury. Addressing the vision problem often facilitates the benefits of other therapies. Neuro-Optometrists diagnose and treat in order to maximize the patient's outcome. The ultimate goal of these services is to improve the patient's quality of life.
There may not be an eye injury, but rather a problem of how the eyes move or how someone understands how they see. Some common problems include:
- Strabismus (eye turn)
- Binocular Vision Dysfunctions (the ability to coordinate the two eyes to work together)
- Reduced visual acuity at far (how clear the letters are at distance)
- Reduced visual acuity at near (how clear the letters are at reading distance)
- Accommodative Disorders (physically focusing the eyes)
- Difficulties in visual perception (are objects where I think they are?)
- Visual Field loss (not being able to see on the right side of the right eye, for example)
- Deficits in visual motor (eye movement problems)
- Ocular Motility disorders integration (putting together eye movement with body movement)
- Visual Information Processing (making sense of what you see)
These visual issues then affect how someone is able to function on a daily basis.
Common Visual Problems connected with Brain Injury
Common symptoms that people experience include:
- Double vision
- Blurred vision
- Eye strain
- Abnormal posture
- Head tilts or turns
- Eye turn
- Bumping into objects
- Closing or covering one eye
- Balance and coordination problems
- Reduced ability to sustain attention on visual tasks
- Poor judgment of depth
- Confusion related to visual tasks
- Reduced ability to accurately
- Difficulty reading localize objects
Top Three Vision Problems arising from Brain Injury or Stroke
Although there are many visual problems that arise from brain injury and stroke, three are more devastating and impairing than the rest. These are
visual field loss, intractable double vision, and visual / balance disorders.
Visual Field Loss
With a visual field loss the patient is literally blind to half of their field of vision. This places the person at increased risk of further injury and harm from bumping into objects, being struck by approaching objects, and falls.
A two fold approach is used to treat visual field loss. Visual rehabilitation activities are prescribed by the doctor and administered by the therapist to teach scanning of the hemianopic field loss. This is a difficult task. It is the act of seeing something that brings our visual attention and scanning to bear. However, these patients do not see to the field they are being trained to scan and attend. Therapy is aimed at teaching that and several approaches have been developed to assist in this, but remediation still requires a lot of effort and patience.
Special visual field awareness prism lenses are used in treating visual field loss. As the patient scans into the prism the optics are shifted so as to perceptually gain about 15 to 20 degrees of visual field recognition. Since diplopia is perceived when scanning into the prism, fixation in the prism must be brief. These are used as spotting devices only to determine if there is an object in the periphery that deserves further visual attention. When such an object is spotted, the patient turns their head to view it in detail with their intact central vision.
Double Vision ( Diplopia)
Double vision (diplopia) is a serious and intolerable condition that can be caused by strabismus, ophthalmoplegia, gaze palsy, and decompensated binocular skills in patients with brain injury, stroke and other neurologically compromising conditions. Prisms, lenses and / or vision therapy can oftentimes help the patient achieve fusion (alignment of the eyes) and alleviate the diplopia. If and when these means are not employed, the patient may adapt by suppressing the vision of one eye to eliminate the diplopia. If lenses, prisms, and / or therapy are not successful and the patient does not suppress, intractable diplopia ensues.
In this population of patients, patching has frequently been used to eliminate the diplopia. Although patching is effective in eliminating diplopia it causes the patient to become monocular. Monocular as opposed to binocular vision will affect the individual primarily in two ways; absence of stereopsis and reduction of the peripheral field of vision. These limitations will directly cause problems in eye hand coordination, depth judgments, orientation, balance, mobility, and activities of daily living such as playing sports, driving, climbing stairs, crossing the street, threading a needle etc.
A new method of treating diplopia that does not have these limitations has been successfully evaluated. It is called the "spot patch" (invented and
named by this author) and is a method to eliminate intractable diplopia without compromising peripheral vision. It is a small, usually round or oval, patch made of dermacil tape, 3-M blurring film (or another such translucent tape). It is placed on the inside of the lenses of glasses and directly in the line of sight contributing to the diplopia. The diameter is generally about one centimeter, but will vary on the individual angular subtense required for the particular strabismus, or gaze palsy.
Visual Balance Disorders
Visual balance disorders can be caused by a Visual Midline Shift Syndrome (VMSS), oculomotor dysfunction in fixations, nystagmus, and disruptions of
central and peripheral visual processing. A full description of these disorders is beyond the scope of this paper. The treatment will depend on the visual diagnosis and etiology. Lenses, prisms and visual rehabilitation activities are used in the remediation of these disorders.
Neuro-Optometric Treatment through Vision Therapy
Neuro-Optometrists have special training and clinical experience in this area and are able to help those who have vision problems related to brain
injury. Neuro-Optometrists understand how specific visual dysfunctions relate the to patient's symptoms and performance. They can provide solutions to these problems so that the entire rehabilitation program (OT, PT, Speech, etc.) is then more effective.
The evaluation of the patient with brain injury may include, but is not
limited to, the following:
- Comprehensive eye and vision examination
- Extended sensorimotor evaluation
- Higher cerebral function assessment of visual information processing
- Low vision evaluation
- Extended visual field evaluation
- Electrodiagnostic testing
Optometric management of the patient with brain injury may include the
- Treatment of ocular disease or injury either directly or by comanagement with other healthcare professionals
- Treatment of the visual dysfunction with lenses, prisms, occlusion, and optometric vision therapy
- Counselling and education of patient, family, or caregiver about the patient's visual problems, functional implications, goals, prognosis, and management options
- Consultation with other professionals involved in the rehabilitation and health care of the patient.