Visual field cuts are common among stroke survivors. This common consequence can cause safety issues, falls and loss of driving privilege. Assessing and understanding visual field cuts are discussed here. This post will discuss the techniques I use to improve visual field cuts following stroke and TBI.
Having the patient’s vision assessed by an eye doctor is always the first step. Understanding your patient’s vision history will be vital to understanding current visual complaints. Ideally, an Easterman assessment will be completed with the therapist getting a copy of the exam to be aware of the baseline. Periodic re-assessment of the visual field will be required to check for progress. I typically recommend reassessment after 10 visits. If no progress has been made at this point, I recommend the patient stop the treatment. In past cases, if no progress was made after 10 treatments and the treatment was continued, no progress was made after an additional 15 treatments.
Patient selection
Some patients with field cuts do better than others. In my experience, those with neglect, particularly those with poor awareness of their condition, tend to become frustrated with the interventions as they feel they are wasting time attempting to correct a condition they do not think they have.
I have had the most success with patients having fields cuts related to occipital lobe strokes as opposed to strokes caused by middle cerebral artery issues. These MCA strokes have a higher incidence of attention/neglect (particularly left side affected). While I have had more success with younger patients, age should not disqualify a patient. Medical instability and neurological history all play a role in reaching the patient’s goals with results not being as good for patients with more complex medical histories.
What is success?
The typical patient with field cut loss is wanting to resume driving. Many states have specific visual field requirements for driving (130 degrees in Florida). Investigation of this requirement will be a part of helping the patient with the visual field cut. As therapists know, driving is a complex task with adequate vision being only part of the skills needed to safety operate a vehicle.
While the patient may not show sufficient improvement to met the states requirement for driving, the patients do tend to show improved spatial awareness and safety during ambulation and basic ADLs. I explain all of these things to the patient during our initial assessment and explain that I do not guarantee the will be able to resume driving following our treatment.
The Treatment Session
In my clinic, I have a Sanet Vision Integrator (similar to Bioness Integrated Therapy, System, DynaVision and other large touch screen devices) which I use extensively in field cut rehabilitation.
In early sessions, I begin with monocular scanning with cuing to keep the head still during these tasks, usually focusing on central field scanning (a setting on the SVI that encompasses the middle 2/3rds of the screen rather than the full screen). The early goal is to facilitate searches in the missing field without head movement. I will also do quadrant loading in the affected field, continuing to monitor for head movement.
My goal with field scanning is to see quadrant times, get closer together with the goal being less than .4 of a second difference between the fastest and slowest quadrants.
The patient performs saccade strips with the red/blue letters (called monocular fixation in a binocular field-“MFBF”) starting with the strips close together and widening until the saccades become inaccurate (noted by difficulty finding the next line on the right to left sweep or head movement). We practice at this width until there is sufficient improvement to continue.
The hand speed task as well as the saccades 1 and 2 tasks on the Sanet are also useful in improving field scanning.
Having the patient do word searches on paper has been a useful addition to the field cut interventions as a home program. This may initially be frustrating but, with practice, the patient will improve.
I typically apply binasal occlusion to help improve peripheral awareness during the first session for the patient to wear at all times.
When available, Peli-Lens are added to the patients glasses to be used when outside of treatment sessions as well.
Other Vision issues
It is not unusual for the stroke survivor to report other visual issues. I commonly find that while patients have good fusion, the transition from near to far may be slow. This can be improved with convergence/divergence tasks.
Does it work?
I have successfully helped over half of my field cuts patients meet the state’s visual requirements for driving. Given the complex nature of driving, some have chosen not to resume driving for other reasons such as reduced reaction time or cognitive issues resulting from their stroke. Only the eye doctor can assess the patients visual filed and approve them to resume driving.
Without a device like the Sanet or Dynavision, field cut remediation would be much more difficult. Use of letter/number searches on a chalkboard may be helpful and worth trying. The saccades tasks on EyeCanLearn.com may also be helpful.
Not sure where you are located I would be interested in some low vision therapy work. My stroke was 9/4/2021 while I had Covid
I am Pensacola Florida. You can email me at visionrehabot@gmail.com for more information.
We recently found that our 17 year-old daughter has no left side peripheral vision in either eye. She is hemiplegic, suffering from an in utero stroke . In my online search for finding her the right help, I came across a neuro optometrist whose practice is about a 3 hour drive from our home. A friend also suggested that I consult with you and/or another optometrist who does vision therapy. I want to make sure we find the best match for helping my daughter regain some or all of her peripheral vision. Would you be so kind as to explain to me how your treatment would be similar to or different from a neuro optometrist or other optometrist for vision therapy? Also, based on her specific injury, what is the likelihood of success in restoring any portion of her peripheral vision?
Below I am copying the results of her original MRI (taken at 8 months). I will also mention that with a lot of physical and occupational therapy, as well as specialized reading instruction, she functions very well both physically and academically. She is a very hard worker, and if she is very receptive to any exercises or therapies that will help her to progress.
MR Imaging was performed on the brain using multiple pulse sequences in a closed high field strength MRI.
There is a porencephalic cyst identified involving the junction of the right posterior frontal and anterior parietal lobes extending to the ventricular system. This is not completely lined by gray matter but, instead, shows gliotic increased T2 signal intensity on the T2 weighted images and FLAIR images. There is volume loss within the entire right hemisphere with dilation of the temporal horn on the right lateral ventricle with atrophy of the temporal lobe. The posterior aspect of the right thalamus is not formed, and there is atrophy of the right cerebral penduncle.
There is no evidence of mass lesion or midline shift. No extra-axial fluid collections or acute hemorrhages are identified. There is no evidence of hydrocephalus.
IMPRESSION:
Phorencephalic cyst identified within the posterior right frontal lobe and anterior right parietal lobe with surrounding gliosis. There is volume loss within the entire right cerebral hemisphere with agenesis of the posterior aspect of the right thalamus and an atrophied right cerebral penducle. The findings are most suggestive of an in utero insult with resulting encephalomalacia. Though the finding has a similar appearance to an open lipped schizencephalic defect, the cystic structure is not entirely lined by gray matter greatly decreasing the likelihood that diagnosis.
Hi Connie
I am going to keep this post private.
There would not be much difference in the interventions offered by a vision therapy doc or a neuro optometrist. The neuro doc would have more specific training for a field cut, but this is not an uncommon condition so both would be similar. Be aware that either would most likely be cash based with insurance not be accepted.
My office is in Pensacola, Florida. I have had training from the Neuro Optometric Rehab association and have worked with many people with field cuts with varying results. Generally there were older (60 year old and over) patients. There are many factors that affect the outcome of field cut interventions.
I am an occupational therapist and I work at the Pearl Nelson Center. We take all insurance. I would be happy to assess your daughter and see if can help. The process starts with a physician referral from a doctor sent to my office. You can call 8504347755 and one of our team can help you through the process.
Have a great day
Robert Constantine
Visionrehabot@gmail.com