Mark Takesuye, OD; Dan Fortenbacher, OD, FCOVD�|�Wow Vision Therapy, St. Joseph, MIVision Therapy and Rehabilitation Resident

�ABSTRACTTreatment of brain injury in the vision therapy office has become increasingly more common. This case report reviews treatment strategies of post trauma vision syndrome, focusing on virtual reality headsets.

�CASE HISTORYA 26 year white male presents to Wow Vision therapy with symptoms of double vision and blur following a motorcycle accident 5 months before the initial exam. He suffered bifrontal hemorrhagic contusions and shearing injuries to the brain. CT/MRI showed small intraventricular hemorrhages in the occipital horns bilaterally, all of which caused the patient to be in a coma for 3 weeks. He has a moderate cognitive level and reports double vision 5-10 times a day with constant blur, with associated symptoms of frequent headaches, difficulty with balance and movement, decreased attention, fatigues easily, and has difficulty following a series of directions. Patient previously wore glasses for myopia, without prior history of ocular disease. Current medications are sertraline, amantadine, and trazodone.

�VISION THERAPY EXAM FINDINGS• Entering corrected distance VA:

—OD: -5.50 DS 20/25 OS: -5.00 DS 20/20

• EOMs: full and unrestricted OU

• Distance cover test: 2-3pd constant right hypertropia with 10pd esotropia component

• Near cover test: 4-5pd intermittent right hypertropia— Increases in left gaze and in right tilt

• Humphrey C-40 visual field: full OD, OS

• Retinoscopy:—OD: -5.75 DS 20/25 OS: -4.75 DS 20/20

• Red/green NPC: break 12”, recovery 7”

• King-Devick psychometric oculomotor testing: < 6 yo: errors. Poor, sluggish motilities.

• NRA: Break +2.75, recovery +2.50

• PRA: break -0.25; recovery +0.25

• MEM: +1.00 OU, positive response with trial frame

• Visual midline shift 1 inch left of midline—2pd BU yoked prisms work best subjectively, able to tolerate 10pd without

difficulty

• Wheelchair bound, consistently leans to left

• Decrease of range of motion in left elbow

• Mild left hemiparesis

• Slurred speech

�DIAGNOSES• Right Hypertropia• Convergence Insufficiency• Suppression of Binocular Vision• Fusion with Defective Stereopsis

• Deficiencies of Saccadic Eye Movements

• Accommodative Insufficiency• Myopia

The above diagnoses in conjunction with a history of a brain injury are consistent with an overall diagnosis of post-trauma vision syndrome.

�MANAGEMENT• Initial treatment

—+1.00 FT28 bifocal add based off MEM and trial frame. —Compensatory prism: 1pd BD OD, 1pd BU OS. — Initiated vision therapy

� Manage diplopia and suppression� Stabilize accommodation, oculomotor deficiencies, binocular vision

� Increase performance on visual perceptual testing.

• First progress evaluation: consider binasal occlusion. With decreased symptoms of diplopia, increased stereopsis, and reports of improved focusing ability, binasal occlusion is not warranted at this time.

• Fourth progress evaluation: session 38 —Oculomotor and accommodative areas resolved. —NPC, binocular vergence ranges, stereopsis, and fusion have been inconsistent and need improvement

� NPC: four inches� Fusion: central suppression ≥ 4 feet, distance peripheral fusion

� Distance stereopsis: 180”� Near stereopsis: 200”

—Symptoms of headache, blur, and diplopia have improved but remain.—Prescribe 20 additional VT sessions.

TABLE 1: PROGRESSION OF FINDINGS AFTER INITIATION OF VIVID VISION THERAPY

SESSION 38 SESSION 51 SESSION 58 SESSION 64

Red/Green Near Point of Convergence

Break: 4" Nose Nose Nose

PhoriaDistance: 9 EPNear: 3 EP

Distance: 5 EPNear: 1 XP

Distance: 6 EPNear: 2 EP+1.00 Near: 1 EP

Distance 10 EPNear: 6 EP+1.00 Near: Ortho

Fusion

Fusion <4'Central suppression ≥ 4'Distance peripheral fusion Fusion on distance vectographic targets

Fusion <2'Diplopia 3-8'Fusion at distance

Fusion <6', >8'Diplopia 6-8'No suppression

Fusion <5', >6'Diplopia 5-6'No suppression

StereopsisNear: 200"Distance: 180"

Near: 100"Distance: none

Near: 40"Distance: none

Near: 20"Distance 40"

• Vivid Vision used for nine sessions for 10-15 minutes in office. —By session 64, consistent improvements observed in NPC, suppression and stereopsis.

� NPC: Nose � Fusion: fusion less than five feet and greater than six feet. Diplopia between five and six

feet. No suppression. � Distance stereopsis: 40” arc � Near stereopsis: 20” arc

—Complaints of headaches, blur, and spatial issues are resolved, and diplopia is infrequent and only at near.

� Prescribe binasal occlusion for near work with SVN readers.

—Vergence ranges remain low, particularly accommodative convergence, with an AC/A of 1:1. Phoria remains more esophoric at distance than near, with variable and inconsistent distance stereopsis.

�OUTCOMEAll areas of binocular vision improved except for deficiencies in fusional vergence ranges at distance and near in upgaze. Three of four major goals were achieved: single vision, balance, and headache relief. The final goal of attention was improved every month, with plans to visit a psychologist to evaluate for ADHD, as attention was an issue before the TBI. By the end of treatment, all symptoms were significantly decreased evaluated monthly with a symptoms survey.

�DISCUSSION• Post trauma vision syndrome

—Symptoms: asthenopia, HA, diplopia dizziness, inability to focus, movement of print with reading, problems with fixation and tracking.1,2 —Treatment: binasal occlusion and base-in prisms proven effective by VEP testing. Allows for easier bifixation, and can eliminate diplopia in some cases.

• Visual midline shift syndrome —Symptoms: intermittent blur, appearance of movement in stationary objects, appearance of tilted floors, and difficulty with balance and spatial orientation. Common to have shift of midline away from affected side of body. Can be anterior, posterior, or lateral, often times causing postural shifts.2,3 —Treatment: yoked prisms to recenter midline and restore balance. To be used for short durations daily to train the weight bearing relationship to the ambient system. Often times, clinicians and patients recognize an immediate change in posture.

• Cause of visual changes in PTVS and MLSS —Thought to be from damage to the ambient visual system.

� 20% of magnocellular nerve fibers branch around the lateral geniculate nucleus to the superior colliculus, which integrate with vestibular, proprioceptive, tactile, auditory pathways in the midbrain and brainstem, which are commonly sheared or compressed in TBIs.

� VEP amplitude decrease shows that binocular cortical cells are compromised. Ampli-tudes increase with binasal occlusion, providing structure to the environment, and BI prism, providing field expansion.1,4

• Binasal Occlusion —Applied since 1950 for strabismus. Now used to treat amblyopia, anomalous correspondence, post-trauma vision syndrome, esotropia, esophoria, vertical deviations, asthenopia, and hyperfocal patients.5

—Two formal studies done using VEP amplitudes as a measure. Both binasal occlusion with BI prism and binasal occlusion alone restore amplitudes to near normal in TBI patients.1,6

—Often times provides immediate and frequently full relief from disturbing motion in visual field in specific sets of TBI patients.6

—Results in reduction of separation of diplopic images, improved spatial ability, and increased comfort and affect. Angle of deviation decreases, posture improves, and binocular testing results improve as well.7

• Requirements for effective top-down therapy8,9

—Motivation/active participation: conscious goal directed effort

—Repetition: repeated stimulation of a neuron increases synaptic strength

—Feedback: Recalibrate and refine encoded responses

—Motor match to a sensory mismatch: visually guided motor skills

—Multi-sensory integration: balance, motor, auditory

�VIVID VISION• Setup of Vivid Vision therapy using Oculus Rift. Patient uses stereopsis

to find nearest bubbles, and uses hands to touch target, incorporating kinesthetic awareness

• Uses the Oculus Rift virtual reality headset as a means to reestablish sensory fusion, vergence, and depth perception. Features also allow for training of amblyopia.

• Dichoptic images at variable degrees of separation with suppression checks allow for feedback and diplopia awareness

• Activities are engaging, allowing for extended use of treatment and for repetition, an important factor in neuro-rehabilitation.

• Action video games have been proven to increase spatial attention and stereoacuity.10

• Video game dichoptic tasks have previously shown to have positive effects on amblyopia, fusion, and stereopsis.11

• Modifiable features —Angle of deviation

� Modifying the angle of deviation builds amplitudes of vergence ranges, and can be toggled between convergence to divergence for facility training.

—Antisuppression checks with size variability � Combined with flat fusion targets to monitor for suppression and diplopia.

—Occlusion, blur, and contrast to decrease image quality to fellow eye

• Depth: the three-dimensional environment projects a sense of depth to the patient as the objects move nearer. Several activities require stereopsis for positive performance.

• Kinesthetic: several activities involve hand and arm movement to interact with the stereo-demanding target increasing the incentive for fusion.

• Peripheral awareness: most activities require focus on environment in order to find targets or to avoid obstacles in a timely manner. Head

movement with the device is integrated with a correlating change in environment.

• Target size: variable sizes allow for modifiable levels of difficulty to stimulate fusion.

• Spatial vision: orientation with head movement allows the user to define “where am I?” or the antigravity process. Finding targets allow for the “where is it” factor, or the centering process. It uses fixations, pursuits, saccades, and vergence as objects move in space. The “what is it,” or identification process is necessary to perform well in the games. Traditionally, this is based on accommodation, but in a virtual environment, accommodation is fixed, but has to respond to accommodative convergence to remain focused at the correct distance. This activity allows for visual guidance of hand movement, as well as secondary movements with a controller, and throughout the activities, the patient is asked to communicate what they see, contributing to the speech-auditory component of vision.9

• In this case, after general skills were abated, suppression, NPC, and stereopsis were variable, and did not seem to be improving. Vivid Vision therapy was initiated for nine sessions, along with other ther-apies, and significant improvement in each of the above areas were observed. Not only was there improvement, but trends seemed more stable and repeatable. Similar activities as prior to Vivid Vision were performed in the categories of oculomotor accuracy, accommodation, and vergence. Oculomotor stretching exercises were introduced with more focus on visual perceptual abilities (mostly memory and visualiza-tion). Vergence activities were moved into free space.

�CLINICAL PEARLS• Vivid Vision is beneficial in late stages of neuro-rehabilitation to elimi-

nate suppression, increase stereopsis, and NPC.

• Virtual reality headset training fits the criteria for an effective top-down therapy for head trauma.

• When testing results become inconsistent, a new approach may bene-ficial to improving test data and subjective complaints.

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(PTVS) in patients with traumatic brain injuries. Brain Inj 1994 May-Jun;8(4):393.2. May JM, Smith JR. Post-trauma vision syndrome. Poster presentation at NAN convention, San Francisco, CA. Nov

1995.3. Padula WV, Argyris S. Post trauma vision syndrome and visual midline shift syndrome. NeuroRehabilitation 1996;

6(3):165-714. Sanet RB. Trees-forest ratio: focal-ambient visual processing. Presentation at IV International Congress of Behavioral

Optometry. Versailles 2002. 5. Proctor A. Traumatic brain injury and binasal occlusion. Optometry & Vision Development 2009; 40(1):45-50.6. Ciuffreda KJ, Yadav NK, Ludlam DP. Effect of binasal occlusion (BNO) on the visual-evoked potential (VEP) in mild

traumatic brain injury (mTBI). Brain Inj 2013; 27(1): 41-477. Gallop S. A variation on the use of binasal occlusion. The Journal of Behavioral Optometry 1998; 9: 31-35.8. Chang A, Cohen AH, Kapoor N. Top-down visual framework for optometric vision therapy for those with traumatic

brain injury. Optom and Vis Performance 2000 1(2): 82-939. Suter PS, Harvey LH. Vision Rehabilitation. 1st Ed. Florida: CRC Press, 2011.10. Li RW, Ngo C, Nguyen J, Levi DM. Video game play induces plasticity in the visual system of adults with amblyopia.

PLoS Biol 2011 Aug; 9(8): e100113511. Hess RF, Thompson B, Black JM, Maehara G, Zhang P, Bobier WR, To L, Cooperstock J. An iPod treatment of

amblyopia: an updated binocular approach. Optometry 2012 Feb 15; 83(2): 87-94

SOUTHERN COLLEGE OF OPTOMETRY

A Vivid Approach to Traumatic Brain Injury Rehabilitation: Virtual Reality Headsets and Post Trauma Vision Syndrome