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Senior man with low vision after stroke

Hemianopsia - Vision Loss After A Stroke Or Brain Injury

Errol Rummel OD, FAAO, FNORA
Jackson, NJ

This protocol is only to be used when Rx’d by an optometrist or when under the in-person supervision of an optometric physician, a physical therapist, or an occupational therapist.

The Care Of Hemianopsia And/Or Neglect

Patients who have had a stroke or traumatic brain injury may lose one half of their side vision to the right or left. This is called “hemianopsia”. Patients who have a hemianopsia are usually very aware of the side vision loss.

“Neglect” (also known as hemi-spatial inattention) is the inattention to, or lack of awareness of visual space to the right or left and is usually associated with a hemianopsia. The symptoms and signs of hemi-spatial inattention are:

  • The patient cannot or does not, readily or spontaneously scan into the area of the hemianopsia.
  • The patient doesn’t have a conscious awareness of the existence of their field loss.
  • The patient consistently bumps into things on the side of the hemianopsia.
  • When reading, the patient misses parts of words on the side of field defect and/or during a visual acuity test, misses letters on the eye chart on that side.
  • The patient postures with a head or body orientation away from the side vision loss.
doctor using rummel rehab protocol with eye care patient
Rummel Rehabilitation Protocol

These procedures are not in any particular order. it is up to the healthcare professional to decide the order, based on the patient's interest and/or ability.

  • Train the patient to visually scan (pursuits and saccadics) monoculary in the direction of the field loss, but emphasize scanning with minimal head turning. When monocular scanning is performed well, then binocular scanning can be trained. After that, a head turn is acceptable as long as it always follows a visual scan.
  • Perform eye movements in the direction of the field loss re-enforced with auditory input (snapping the fingers or use of a "clicker" or bell).
  • Have the patient walk around the room in the direction of the affected side in order to create a visual-motor map of space on the neglected side.
  • Have the patient use a flashlight aimed alternately toward each foot while walking, to enhance vision with visual-motor reinforcement on the affected side. At first, the flashlight is held by the hand which is not on the side of the field loss. Later on, the hand on the side of the neglect should be used.
  • Encourage the playing of games like crossword puzzles and hard copy card playing (not computer games), but they must cross the midline toward the affected side.
  • Increase sensory awareness on the affected side. Have the patient squeeze a ball on the side of the field defect and then have them scan visually in that direction to find the ball. Have the patient trace a line that extends toward and through the field defect. Place the patient's finger in the area of neglect, with the therapist rubbing the patient's finger to stimulate sensory awareness on that side, and then have the patient scan visually to find the finger.
  • Tell the patient to forcibly/rapidly move it eyes as far toward the field loss while sensing the feeling of their eyes at the extreme gaze. Encourage the patient to become aware of the "feel" of their eyes when gazing toward that side.
  • To encourage frequent visual scanning toward the hemianopsia repeat with eyes closed while walking, have the patient wear a "beeper-timer" wristwatch set to beep at intervals, as a reminder to scan regularly toward the field deficit.
  • Teach patients with hemianopsia to visually scan about 20° toward the field loss, and only then to turn the head in the direction of the field loss. This prepares the patient for the scanning eye movements required when Rummel Side Vision Awareness Glasses are prescribed.
  • Use therapies to stimulate visual and physical movement into the area of neglect, like balloon catching/tossing, and also searching for predictive (and later non-predictive) stimuli in the neglected field.
  • Turning a page at a 45° angle will improve reading ability for some patients with hemispatial neglect who do not respond to other treatments.
  • Enhancing the potential "blindsight" of hemianopsia will allow a patient more spatial awareness (at a subconscious level) within their hemianopic field defect.

Some patients with blindsight, after a while may be able to detect the orientation of a vertical or horizontal line, the color of a green or red object, and/or can point to the approximate location of a moving object held within the area of the field loss. "Blindsight" awareness training should be attempted with every hemianopic patient.

  • Teach the patient to read while using a "Rummel Hemianopsia Reading Guide". These unique reading guides are much more effective (and more professional) than a line drawn with a marker down the edge of the patients reading the material.
  • Use "Rummel Hemianopsia Buttons" to instruct the patient's family to learn to sit on the side of the neglected field, in order to encourage the patient to attend to space on that side. The hemianopsia button is also worn by the patient in the OT/IDT treatment room, allowing busy therapists to be immediately aware of whether the patient they are treating has a right side or left side hemianopsia without having to refer to the chart.
scanning for signs of low vision after stroke
Procedure 1: (Desktop Scanning)
  • Have the patient sit in a chair with both feet flat on the floor. Spread a group of simple three dimensional shapes (i.e. Colored cubes or shape blocks) on a table in front of the patient within their physical reach.
  • Depending on the patient's ability level, either verbally call out the color and/or the shape and have the patient touch the called out target. It is very important to encourage reaching and touching of the target in order to provide the motor stimulation that aids in the development of the visual motor map of space, to enhance the accuracy of saccadic and pursuit eye movements.
  • Give the patient clues verbally and physically by waving your hand in the general location of the target if the patient is unable to locate to the target.
  • Encourage the patient to visualize the full visual field.
  • Encourage the patient to verbalize.
  • To make the exercise more challenging, add a cognitive demand. While the patient is searching for the targets, have him/her do math problems or sell words.
  • Perform the exercise timed and encourage increased speed.
  • Decrease the motor component of reaching and touching as target localization improves
man using low vision wall scanning device
Procedure 2: (Wall Scanning)
  • Have the sit or stand about 10 feet in front of a large uncluttered wall. Spread a group of targets (can be memory game card pictures, playing cards, word flash cards, math problems, etc. based on the patient's performance and cognitive level) on the wall in front of the patient. Place more targets in the missing or neglected visual field, but make sure there are least a few targets in all fields.
  • Have the patient hold a matching set of targets (memory card matches, corresponding suits of playing cards, or answers to math problems) in their hands.
  • Have the patient turn up a card in their hand and then visually locate its match on the wall.
  • Give the patient clues verbally and/or physically by waving your hand in the general location of the target if the patient is unable to locate the target.
  • Encourage the patient to visualize the full visual field.
  • Encourage the patient to verbalize.
  • To make the exercise more challenging, add a cognitive demand. While the patient is searching for the targets, have him/her do math problems or spell words. Make sure cognitive demand does not deter significantly from visual scanning performance.
  • Perform the exercise timed and encourage increased speed.
  • Add forward and backward walking and/and or add a balance board or beam.

"Side Vision Awareness Eyeglasses" (SVAG)

Eyes with painted colors around

Ordering Rummel Reading Guides And Rummel Buttons

Note: Please be in touch with your local low vision doctor as to how to obtain this device.

  • For Right Hemianopsia Buttons, Order # AFR225R
  • For Left Hemianopsia Buttons, Order # A=R225L
  • For Reading Guide Set (for Right and Leit Hemianopsia), Order #ER049

Hemianopsia is one of the most common side effects of a stroke or traumatic brain injury. It can leave the patient disoriented, and struggling just to make it through their day. Patients can find themselves afraid to go out, concerned about their safety. If you're suffering from side vision loss, or someone who cares for such a per­son, let your doctor know about SVAG.

Once a patient has learned compensatory visual scanning in the direction of the hemianopsia, advanced optical technology prescription Side Vision Awareness Glasses (SVAG) developed by Dr. Rummel should be considered for safer ambulation, and to enhance activities of daily living in the direction of the field loss.

Read What Some Patients Are Saying And Learn More About Side Vision Awareness Glasses

SVAG Bring The Objects Toward The Left Into My Vision

Most note­worthy has been spotting hanging traffic lights installed on the left-hand side of the street, bring­ing them into full view. Walking in rural or urban areas I am more aware of my surroundings and can better avoid bumping or tripping. On the lighter side when sitting in the passenger seat of the car, I am able to see the speedometer and monitor my husband's speed.

The Use Of SVAG Have Been Very Helpful When Shopping

The use of Side Vision Awareness Glasses have been very helpful when shopping, helping me to avoid items left by clerks on the floor. They also help me maneuver through obstacle courses of items such as carts or floor displays. Also while walking in the neighborhood, I can more easily watch for cars before crossing the street.

Hemianopsia Is One Of The Most Common Side Effects

Hemianopsia is one of the most common side effects of a stroke or traumatic brain injury. It can leave the patient disoriented, and struggling just to make it through their day. Patients can find themselves afraid to go out, concerned about their safety. If you're suffering from side vision loss or someone who cares for such a person, let your doctor know about SVAG.

SVAG Were De­veloped By Dr. Errol Rummel Of Jackson!

After years of treating people with stroke-related, or brain injury related hemianopsia (side vision loss). Dr. Rummel is Director of the Low Vision Care Cen­ter, Jackson NJ, and is the Director of the Neuro­optometric Rehabilitation Clinic at the Bacharach Institute for Rehabilitation, Pomona, NJ.

Having designed and prescribed hundreds of opti­cal systems to expand side vision, he realized a more effective optical field expansion device was needed, and that a detailed system was necessary for doctors to learn how to accurately examine, prescribe, and instruct a patient in using such a device. He learned what worked and what didn't work, and designed an advanced optical technology called SVAG (Side Vision Awareness Glasses) and devised a protocol to be used by doctors in order to effectively examine and prescribe the special glasses for those with hemianopsia.

SVAG Have Important Advantages

  • SVAG have a high ABBE value, so they reduce distracting color aberrations seen through other lenses.
  • They have a higher index of refraction, so SVAG is a thinner and more cosmetically acceptable lens, without an obvious line on the front of the lens, and without an unsightly thick button, or lens strip inserted through the front of the lens.
  • Thanks to better contrast sensitivity than found with Fresnel-lens based glasses, SVAG provide improved vision.
  • SVAG have the widest viewing area, allowing better field awareness in the direction of the hemianopsia than button lens systems. And because SVAG have a vertical edge, the person with hemianopsia just needs to move their eyes a couple of millimeters to get into the SVAG area of the lens, instead of having to travel past the curve of a button lens in order to find the widest possible viewing area.
  • SVAG are easy for people to use because they don't superimpose a narrow peripheral image over a per­son's central vision (which is confusing and difficult to learn to use).
  • SVAG are more attractive because the front of the lens is smooth. When the glasses are worn, the SVAG lens is barely noticeable.
  • SVAG are less likely to accidentally break because there is no glued seam splitting through the lens from front to back as found in older attempts at field expansion.

Hemianopsia can leave people disoriented, inse­cure, and struggling to make it through the day. In addition, there are hemianopsia-related safety is­sues, such as bumping into furniture, walking into people at the mall, falling off a curb, and difficulty performing other activities of daily living. SVAG can give those with hemianopsia more freedom, independence, and safety. Using SVAG may even allow some of those with hemianopsia to return to driving (which may require special on-the-road testing and Motor Vehicle Department approval, depending on state law).

How To Care For Stroke Patients

ODs Can Help These Overlooked Patients With Visual Needs


When it comes to op­tometric care, stroke survivors are often an under-served population especially when most of them have visual or ocular defi­cits. Stroke survivors with visual problems are often dead-ended in neuro-ophthalmology offices because the internists and cardi­ologists who refer them to neuro­ophthalmology don't know that ODs can treat stroke-related vi­sual/ocular challenges. Thus, many op­tometrists are unfamiliar with how they can help stroke survivors. Although a background in behavioral optometry, vision therapy, and/or neuro­optometric rehabilitation is helpful, pri­mary-care ODs can easily learn the ba­sics necessary to treat the most common visual problems of those who have had a stroke.

Almost 800,000 People Suffer A Stroke Every Year...

Almost 800,000 people suffer a stroke every year, and it is the most common dis­ability among American adults.' A stroke occurs when there is an interruption of the blood flow to an area of the brain.

There are two types of strokes: an isch­emic stroke, occurring when a blood clot blocks a blood vessel, and a hemorrhagic stroke, occurring when a blood vessel in the brain ruptures and causes dam­age. Some strokes are preceded by brief episodes of stroke symptoms known as transient ischemic attacks (TIA), which are temporary interruptions of blood supply to the brain. Because a TIA can occur hours, days, or weeks before a full stroke, it behooves us to be aware of the symptoms and signs—temporary episodes of weakness, numbness, paralysis of the face, arm or leg (especially on one side of the body), difficulty speaking or understanding simple statements, and loss of balance or coordination.' These symptoms can occur on only one side of the body. To that list should be added any re­port of momentary diplopia, transient loss of visual field, or a passing episode of blurry vision.

Every primary-care optometrist can—and should—as a minimum perform the following work-up on a patient present­ing with any signs:-    History of stroke-related signs and symptoms Best-corrected visual acuity-    Pupil reflexes Cover test, phorias, ocular range of motion-    Threshold visual field testing-    Dilated fundus examination-    Stethoscope auscultation of the ca­rotid arteries for bruitsWhether a clinical ocular deficit is discovered, any transient visual episode should trigger a call to the patient's inter­nist or cardiologist to urge the physician to schedule the patient for a physical. In addition, I proactively write the patient an Rx for carotid Doppler testing and/or a CT scan—this starts the ball rolling. When a patient presents with a known, previously documented stroke, pay at­tention to current complaints of persist­ing hemianopsia, diplopia, or eyelid dys­function. These conditions can often be treated by the primary-care optometrist.

Optometrists Are Able To Address The Visual Needs Of Stroke Survivors, An Underserved Population

Consider using alternate patching or prism for diplopia. For hemianopsia, prescribe separate pairs of glasses for both distance and near for or consider Side Vision Awareness Glasses designed by the author. Lid massage may help lid paresis.

Diplopia From A Recent Stroke Is Confus­ing To The Patient...

Because adaptation by a head turn or suppression has not yet occurred. Diplopia also causes symptoms of dizziness, poor balance, trouble read­ing, psychological stress, asthenopia, and headaches. Patients with double vision may mention those complaints but not say "double vision" unless asked.

Most stroke survivors with a known cerebrovascular accident (CVA)-related diplopia have been instructed to patch the deviating eye. This makes the patient happy because the patch resolves the dip­lopia. Unfortunately, patching the deviat­ing eye for too many weeks can embed the binocular dysfunction, reducing the possibility of gaining binocular vision.

Therefore, as a minimum, ensure that the eye patch is alternated daily from the right eye to left eye. To keep the schedule simple, I tell patients to patch the right eye on even-numbered calendar days and to patch the left eye on odd-numbered calendar days.

Keep in mind that when patching to compensate for diplopia, the patient may be annoyed or uncomfortable because of the reduced peripheral vision caused by the patch. In those cases, selective oc­clusion can be used by cutting a piece of Transport surgical tape into a small

rectangle to block central vision in front of the pupil of the deviating eye. The tape blocks double vision and allows the pa­tient to retain an awareness of periphery in the occluded eye, which feels more comfortable and is safer than a tradi­tional eye patch.

Some patients with obvious large an­gles of paretic strabismus do not complain of diplopia. That is because the angle of strabismus is so large that the patient can concentrate on the image straight ahead of the non-strabismic eye while ignor­ing (but not necessarily suppressing) the diplopic image located way off center. Although patients may not complain of diplopia, they may still have behavioral symptoms of confusion, poor balance, or poor ambulation due to visual con­fusion induced by the ambient diplopic image. This problem requires consulta­tion with an OD skilled in treating bin­ ocular vision dysfunction.

Stroke-related binocular dysfunctions with mild-to-moderate paretic angles of strabismus often are capable of gaining a wider range of motion of the effected eye. This can be achieved by having the patient monocularly track a moving tar­get (pursuits) in the direction of the re­strictions several times per day for a few weeks.

Prism Glasses As A Stopgap Measure To Help The Patient Feel More Comfortable...

Many patients are told by non-optometric doctors that double vision may resolve on its own within a vague timeline of months without mentioning vision ther­apy or prism. It is dismaying that people with stroke-related hemiplegia are rec­ommended to have physical and occupa­tional therapy, but patients with diplopia are given only an eye patch and not af­forded a chance for binocular rehabilitation. I suggest prescribing prism glasses as a stopgap measure to help the patient feel more comfortable.

Simple vision therapy procedures using a Brock string or red-green tranaglyphs may help until vision therapy is initi­ated. Never prescribe a ground prism into glasses until a two- to three-month trial with a Fresnel prism has shown the angle of deviation to be steady and that the double vision has been resolved.

It is important to prescribe the total amount of Fresnel prism with the pris­matic compensation broken up between the two eyes to allow the Fresnel-induced reduction in contrast to be distributed evenly between both eyes.

For example, if an esotropia-related diplopia is resolved with 20 D base-out prism, it may seem simple to prescribe a single 20 D base-out Fresnel prism before the deviating eye. However, the patient will usually complain of blur in the eye with the Fresnel prism. Two 10 D base-out prisms are a better choice because they equalize the 20 D Fresnel-induced poor contrast, which reduces patient complaints.

Furthermore, splitting the prism power between two eyes allows the freedom to fine tune the prism power when, or if, the patient's angle of deviation changes. Peel off one of the Fresnel prisms and replace it with another power as clinically in­dicated. Keep in mind that the angle of the paresis measured when viewing at distance may be very different than at near, so separate prismatic distance glasses and reading glasses are often required.

When prescribing compensating prism for vertical diplopias, remember that the angle of deviation usually varies depend­ing on head position. Be sure to prescribe the vertical prism with the patient's head in a straight-ahead position and warn the patient that a chin-up or chin-down head position will likely cause him to see double in spite of the prism.

A patient whose diplopia is resolved with prism may begin to complain again of diplopia in a few months. Never as­sume that a renewed complaint of diplo­pia implies a worsening of the condition. It may mean that the strabismic angle is decreasing.

Do not be disheartened if a rare patient can't fuse binocularly with any amount of prism. A prism bar may seem to neu­tralize the diplopia while the patient is in the chair, but you may find that when you prescribe Fresnel prisms, the patient still complains of double vision. At times despite re-measuring, fine tuning, and changing prism power, the patient con­tinues to not fuse the diplopic images.

Some neuro-related diplopias are diffi­cult to resolve because of damage in the brain pathways responsible for the binoc­ular vision reflex, and horror fusionalis, when it occurs, is difficult or impossible

What To Include In A Possible Stroke Workup

History Of Stroke-Related Signs And Symptoms Best-Corrected Visual Acuity Pupil Reflexes

Cover test, phorias, ocular range of motion Threshold visual field testing Dilated fundus examination Stethoscope auscultation of the carotid arteries for bruits to resolve—an alternating eye patch may be the only treatment available.

Stroke-Related Hemianopsia Is Reasonably Common...

Stroke-related hemianopsia is reasonably common. The field defect is obvious on a 24-2 threshold visual field test.

However, some stroke survivors have hemi-spatial inattention (also known as "neglect"), which is an inattention to or lack of sensory awareness of visual space to one side. It may or may not be associ­ated with a hemianopsia.

Patients with hemi-spatial inattention will usually be unaware of their inabil­ity to perceive space on the affected side, may not be able to follow a moving target in the direction of the neglect, and may say that their physician or occupational therapist "said" that they have visual con­cerns to the side (although the patient is not cognitively aware of the hemiano­pic like loss of visual field). That is a difficult concern to address and should be referred to an optometrist skilled in neuro- optometric rehabilitation.

Hemianopsia usually leaves a person disoriented and struggling to make it through daily living. People with hemi­anopsia are often afraid to leave their homes and are concerned about their safety. They are confused in a busy visual environment—such as the mall where they may bump into people—or have the fear of falling off a curb.

Hemianopsia can cause a sense of loss of independence due to discontinuing driving. Others find that ambulatory ac­tivities are more difficult. People with hemianopsia (but without hemi-spatial inattention) can often be helped by an optometrist.

As a minimum, recommend two sepa­rate pairs of glasses: one for distance and one for near. Separate pairs are needed because with hemianopsia, bifocals or progressive lenses limit the width of the seeing area through the glasses. In my experience, hemianopsia patients usually have fewer field-related complaints with full-field single-vision glasses.

I have prescribed specially-designed eyeglasses over the past 20 years to help those with hemianopsia. The optical care of hemianopsia is based on using prism to expand side vision awareness. Avail­able hemianopsia-related glasses I worked with were difficult to prescribe, difficult for the patient to use, or had optical de­sign flaws.

I learned what worked and what didn't work. I designed a prism technology called SVAG (Side Vision Awareness Glasses) that can be prescribed by any trained optometrist (See Figures 1 and 2).

Prior to developing SVAG, hemianopsia­related eyeglasses afforded only a limited circular viewing area. This limited the patients' appreciation of the expanded field awareness or required a highly-cog­nitive patient who could adjust to simul­taneously viewing straight ahead while noticing out-of-focus peripheral images caused by Fresnel prism.

I developed SVAG with a high Abbe value because patients with older hemi­anopsia glasses complained of distract­ing color aberrations. SVAG also have a higher index of refraction, making them thinner and more cosmetically accept­able. There is also no prism button or Fresnel lens strip on the front of the lens. SVAG provides clear side vision with a wide viewing area when looking through the prism lens.

Some Stroke Patients Develop Blepharopa­resis, While Others Develop Ptosis...

If there is ptosis, avoid disuse of the ptotic eye by taping it open about a centi­meter for five minutes a few times per day using Transpore surgical tape. Be sure to allow enough slack in the tape for blink­ing. Patients should instill an artificial tear every minute to prevent discomfort and drying during the interval the eye is taped open.

If there is a blepharoparesis and the eye won't close, be sure to use Transpore surgical tape to keep the eye closed to prevent corneal staining and discomfort.

After years of watching physical thera­pists work use massage with stroke pa­tients, I decided to try a similar massage technique on the eyelids. I found that some patients with stroke-related ptosis or blepharoparesis responded to an eye­lid massage.

The massage is conducted with your finger, using a brisk moderate stroking of the affected lid in a lateral and radial fan shape. An alternating warm or cool pack applied before lid massages may increase sensory stimulation to the lids, enhancing the effect. Massage for a few minutes four times per day for three weeks. Discontinue if no change in ptosis or belpharoparesis.

Some ptosis patients have what I call diplopic pseudo-ptosis or DPP. Stroke sur­vivors with a stroke-related esotropia or exotropia subconsciously learn to close the offending eye to avoid diplopia. Al­though they will appear to have ptosis, it is not ptosis. Cover the non-ptotic eye; if the patient is capable of opening the apparently ptotic eye, you have discov­ered a DPP.

For blepharoparesis, I sometimes use commercially available eyelid weights to pull the lid down. The lid weights come in a fitting set of graded weights with an adhesive backing. These test weights are used to determine the weight of a gold lid implant used by oculoplastic surgeons. Op­ tometrists can use the test set weights to treat blepharoparesis noninvasively until surgery is indicated.

Specialty optometric consultation is available through colleagues associated with Neuro-Optometric Rehabilitation As­sociation (NORA) and the College of Op­tometrists in Vision Development (COVD).•


1.National Stroke Association. What is stroke? Available at­ stroke/what-stroke. Accessed 3/22/16.

2.National Stroke Association. Transient lschemic Attack. 1999. Print.

Dr. Rummel is director of the Neuro-Optometric Rehabilitation and Visual Perception Clinic at the Bacharach Institute for Rehabilitation. He has developed protocols for prescribing reverse telescope glasses and Rummel Reading Guides are used by occupational therapists and neuro-rehab optometrists to help patients with hemianopsia. He has served in the United States Army as a Captain in the Optometry Section of the Medical Service Corps.

Reprinted with permission from the April 2017 issue of Optometry Times Copyright 2017, Advanstar Communications, Inc. All rights reserved. For more information on the use of this content, contact Wright's Media at 877-652-5295.

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