Traumatic Brain Injury (TBI)
Post Traumatic Vision Syndrome (PTVS)
PTVS involves a constellation of signs and symptoms that occur after certain types of concussions or after multiple concussions. Symptoms include light sensitivity, inability to concentrate and multi-task, memory issues, difficulty coordinating eyes, problems focusing, double vision, blurred vision, headaches, difficulty coping in busy or noisy environments and trouble with balance and coordination. More severe cases can even affect the ability to speak.
The Focal and Ambient Visual Systems
The visual system is composed of two parts:
The Focal System:
The focal system is the part of the visual system that allows you to identify objects in your environment and provides you with your sharp, central vision. It allows you to pay attention to detail in your environment.
The Ambient System:
The ambient system involves our peripheral awareness. It provides the perceptual scaffolding to allow us to orient ourselves in space.
The ambient system is particularly susceptible to damage during a concussion or whiplash injury. MRI’s normally do not show any sign of damage. We believe that the ambient system fibers are being stretched during the injury, resulting in a faulty flow of information to and from this part of the brain.
Damage to the Ambient System
The ambient system performs the following functions:
• The ambient system is a great anticipator. It is always ready for ‘what’s next’. Persons with great ambient systems are athletes. If I were to throw a ball towards a baseball player unexpectedly, he would catch it instinctively. If I threw a ball at a person with a damaged ambient system, it would just bounce off their body before they realized what happened. This causes a reduction in reflexes.
• The ambient system is also responsible for suppression. It is constantly preventing peripheral visual stimuli from interfering with vision. For instance, a person with an intact ambient system could pay attention to their TV set while children were running around the living room. A damaged ambient system results in an inability to cope in busy environments such as casinos. Peripheral stimuli appear to be occurring in front of you, rather than to the side, which can become overwhelming.
• The ambient system also helps our body know where it is in space. As children, our various senses began to work together to help us determine where our body is located. Our kinesthetic sense can ‘feel’ the chair we are sitting on, our inner ears give us information about location as does our ambient visual system. If the ambient system is providing faulty information to this finely-tuned system, the body may choose a new spot for its center of gravity, leading to Visual Midline Shift Syndrome. (VMSS) VMSS is a displacement of the midline of the body after a concussion which results in the world appearing ‘tilted’ to a patient so that they develop abnormal postures and gait as an adaptation response.
• The ambient system is an ‘unconscious’ system. It functions without your awareness or thought. If the ambient system becomes damaged, the ‘thinking’ part of the brain may attempt to take over its function. This means that your brain is now busy consciously operating an unconscious operation and has less ‘brain power’ available for activities that require thought. This results in difficulties with multi-tasking, memory, concentration and even speech.
If the ambient system were to disappear altogether, our world would become an incomprehensible mass of detail and tunnel vision… similar to what we see when driving through a snow storm at night.
Treatment for Post Traumatic Vision Syndrome
Neuro Optometric Rehabilitation
Bedford Eye Care is pleased to be able to offer assessment and treatment services for patients who have suffered a traumatic brain injury (TBI) or concussion.
Your neuro optometrist has spent a considerable amount of time learning how to treat TBI patients and is affiliated with the following organizations:
COVD (College of Optometrists in Vision and Development) Canada Chapter, NORA (Neuro Optometric Rehabilitation Association), COVT&R (Canadian Optometrists in Vision Therapy and Rehabilitation), OEP (Optometric Extension Program), the William Padula Institute of Vision and the College of Syntonic Optometry.
Neuro optometric rehabilitation involves a comprehensive evaluation of the patient’s oculo-visual system including a careful case history, determination of prescription and binocular vision assessment in order to determine if the patient suffers from Post Traumatic Vision Syndrome. The patient also undergoes extensive gait and posture analysis to determine if a Visual Midline Shift Syndrome (VMSS) exists.
This initial assessment takes almost 2 hours to complete.
The fee is $1,006.00*.
After a concussion, patients often experience elevated levels of anxiety and stress. This can be due to an over production of hormones and neurotransmitters associated with the sympathetic nervous system. The sympathetic nervous system is the part of the autonomic nervous system responsible for our ‘fight and flight’ reaction.
If you screen positively for Syntonics treatment, your neuro optometrist will prescribe a program designed to help calm down the over-stimulated brain and sympathetic nervous system.
The program involves breathing and relaxation techniques coupled with a therapy known as Syntonics. Syntonics utilizes selected light frequencies absorbed through the eyes to calm the sympathetic nervous system by way of the retinal-hypothalamus brain connection.
Syntonics therapy begins with an initial assessment to determine the correct wavelength of light required for therapy. Pupil responses and functional visual fields are also assessed.
Treatment consists of in-office Syntonics sessions (initial, week 2 & week 4), in addition to home therapy. Patients are provided with specialized tinted goggles and a bulb so that therapy is continued at home over a 5-week period. Approximately 20 Syntonics sessions at home are required.
Initial assessment (1 hour, 20 minutes): $220
Home therapy: $38.16 for the bulb, $27.50 per syntonic goggle (normally 3-5 goggles may be required)
2 week and 4 week follow-up visits & Syntonic treatments: (50 min) = $120 per visit
Neuro Optometric Reassessment after 6 weeks of Syntonics Therapy
Your neuro optometrist will perform a thorough reassessment, rechecking your pupil function and functional visual fields. Some patients may require an additional 6 weeks of Syntonics Therapy after taking a one to three-month break. (same fees apply)
In addition, specialized therapeutic glasses will be prescribed to allow for comfortable vision and to correct a Visual Midline Shift (VMS), if it is present. (Note: Patients may already received yoked prism glasses after the initial visit if they are required immediately. Reading glasses may have already been prescribed as well.)
You will then be referred to a physiotherapist who is qualified to provide Neuro Visual Postural Therapy. (NVPT)
Week 6 follow-up: (1 hour, 20 minutes) $520.00.
In order to treat PTVS, we often utilize prism glasses to help rehabilitate the damaged ambient system.
In most cases 2-3 pairs of glasses are prescribed.
1. Distance glasses with yoked prisms. These glasses are designed to help offset the ‘tilted’ world you are perceiving. They will help you to walk with more confidence, assist with balance and make the world appear more stable.
2. Sun clips with a dark tint to be worn over the distance glasses or a pair of prescription sunglasses with yoked prisms.
3. Near glasses with a reading prescription and base in or base down prism. These glasses will allow you to read more comfortably and clearly. They should only be worn for computer work and reading as they will blur your distance vision.
Your glasses (other than the sunglasses) will likely have a specialized, bluish tint to help stimulate your ambient visual system and also to help with light sensitivity.
Neuro Visual Postural Therapy (NVPT)
When the evaluation is completed, and you have received your specialized glasses, your neuro optometrist then contacts your physiotherapist to create a program of Neuro Visual Postural Therapy (NVPT) to help correct the visual imbalances and bring the oculo-visual system back to a more normal state. NVPT is a program of movement exercises, combined with ocular exercises that re-establish the damaged ambient visual system so that the focal system can once again be grounded by a working ambient system. NVPT should be performed with the correct specialty spectacles (usually involving prism) so that the visual world is correctly perceived by the patient. Patient’s symptoms reduce and many can return to a more normal life.
Reassessment after completion of Neuro Visual Postural Therapy
After the physiotherapist determines that you have successfully completed the program of NVPT, your neuro optometrist then re-examines you and reviews the entire oculo-visual system to determine the progress that has been made. In many cases, the prescription in the glasses can be modified (usually reduced).** In fact, many patients comment that their prism glasses and/or near glasses are now becoming uncomfortable to wear. This is often a sign of a successful outcome.
This visit involves a more thorough investigation of the binocular vision system to see if deficiencies are still present that require treatment via a program of Vision Therapy.
The follow-up appointment takes about an hour. The fee is $660.00*
*** Note: it is possible that patients may require more than one re-assessment after the initiation of NVPT as some patients have more than one change required in their therapeutic glasses before NVPT is completed.
Vision Therapy (VT) Program
Patients who are still symptomatic after the prescription of Syntonics, therapeutic glasses and NVPT, may be candidates for a Vision Therapy program if there are residual binocular vision problems still present.
Vision Therapy involves in-office therapy sessions (10-30) as well as prescribed home therapy which must be performed 3 times per week. Patients come to the office on a weekly basis for therapy sessions.
Vision Therapy is a series of activities that helps the patient to learn to align their eyes properly, move them as a team in a coordinated fashion, focus accurately at visual targets and maintain fusion for prolonged periods. In addition, VT utilizes methods that ensure integration of various sensory systems, including movement and balance as well as stabilization of the vestibular system with the ocular system. (helping to reduce dizziness and motion sensitivity)
In-office sessions are provided at by a qualified Occupational or Physiotherapist nearest to your home.
Your neuro optometrist will also evaluate your progress at week 5 to 10 (i.e. about ½ way during your therapy) and also after your therapy is completed. (VT over 20 visits, may require a 3rd follow-up visit.)
Vision Therapy: 1-hour session: fee to be determined by your therapist
Optometric follow up visits: (20 min) $220 per visit (1 to 2 required)
Reassessment after completion of Vision Therapy Program
Visual-Perceptual Processing Skills Assessment
Your neuro optometrist will completely reassess the status of your binocular system to ensure that maximum recovery has been achieved.
In addition, a screening of visual-perceptual skills will be performed.
Patients who continue to have visual perceptual processing issues will be provided with a take-home computerized activity program to boost skills in this area.
Optometric reassessment: (50 minutes) $330.
Visual-Perceptual skills program: $160
Final Neuro Optometric assessment after completion of Visual-Perceptual Home Program
Your neuro optometrist will perform a final assessment of perceptual visual skills to assess your progress and symptoms.
Patients who still experience Post Traumatic Vision Syndrome symptoms may be at their maximum stage of healing or may require referral to other health-care providers for additional therapies.
Optometric reassessment: (40 minutes) $220
What are my Chances of Success?
After treating hundreds of patients with concussion, we find that about 70-75% of patients are sufficiently recovered after the Syntonics, therapeutic glasses and Neuro Visual Postural Therapy treatments.
The remaining 25-30% of patients require additional rehabilitation treatments such as Vision Therapy and Visual-Perceptual therapy.
One must remember that we are dealing with a brain injury which may have caused irreversible damage to the neural networks in the brain. Many patients, although feeling much better after therapy, never return completely to their pre-injury ability levels.
Unfortunately, 5% of patients do not respond to prism glasses. If this is the case, and we are unable to fix the problem or adjust the prism prescription, then a full refund will be offered on the therapeutic glasses. (within 3 months of the initial visit) These patients may still benefit from Vision Therapy and Visual-Perceptual Processing Therapy.
* Many insurance companies will cover the cost of our assessments and follow-up visits.
** Bedford Eye Care offers a 6 month guarantee on the therapeutic glasses. Glasses are remade at no charge within 6 months of receiving the glasses if a prescription change is required. However, if an update to a different type of lens is required, the patient only pays the difference in cost. Any changes made to the lenses after 6 months and up to 2 years in the future will receive a 40% discount.
Dr. William Padula lectures on Post Traumatic Vision Syndrome
Dr. William Padula presented a lecture on Post Traumatic Vision Syndrome, including it's causes and treatment in Halifax in April of 2016. This lecture is meant for medical professionals; however, the video is free to watch for the general public.
Watch the lecture here. (3.5 hours in length)
Check out Dr. Merrill Bowan's Binocular Dissonance Grate on his Simply Brainy website.
(Warning: May cause visual distress. Hit the 'Back' button immediately, if it does.)
Many patients with Post Traumatic Vision Syndrome experience difficulty with visually 'noisy' environments.
This grate pattern of black and white stripes has been chosen to be the most disturbing to people with PTVS.
If you find it difficult or nauseating to look at the stripes, or they appear to move or swim, then you might have PTVS.