VISION DEFICITS POST-STROKE

INCORPORATING VISION INTO INPATIENT REHAB

Shannon Corcoran, OTS Loma Linda University

Stanford Hospital March 25, 2016

Guiding Research Question

Does the addition of visual scanning interventions during OT treatment sessions improve functional independence with ADL’s in patients recovering

from a stroke?

OT Practice Framework Client Factors: Visual functions

“Quality of vision, visual acuity, visual stability, and visual field functions to promote visual awareness of environment at various

distances for functioning”

Cerebrovascular Accidents (Strokes) • Acute neurologic dysfunction caused by a lesion in the

brain due to insufficient blood flow to the brain • Can occur via two mechanisms

•  Ischemic stroke: caused by blockage or clot of a blood vessel •  ~87% of all strokes

•  Hemorrhagic stroke: bleeding in the brain •  ~13%

• Upper motor neuron dysfunction produces hemiplegia (paralysis) of one side of the body contralateral to hemisphere of brain with lesion

*Approximately what percent of stroke patients experience

some form of visual impairment?*

Common Vision Impairments Resulting from Strokes

• Visual Field Loss: •  Homonymous hemianopsia: most common

•  Quadtrantanopia •  Scotoma •  Bitemporal hemianopsia (tunnel vision)

• Visual-Perceptual Impairments: •  Diplopia •  Visual midline shift •  Unilateral visual neglect/inattention •  Visual agnosia

• Strabismus • Nystagmus • Cortical blindness

Affected Artery and Corresponding Vision Impairment

Artery Vision Impairment

Middle Cerebral Artery (MCA)

Visual field impairment (B) Visuospatial impairment (R) Contralateral homonymous hemianopsia (B) Visual Perceptual and Unilateral Neglect (R)

Posterior Cerebral Artery (PCA)

Contralateral homonymous hemianopsia (B) Visual agnosia (B) Cortical blindness (R) Visuospatial impairment (R)

Visual Field Loss • Damage to receptor cells along the optic pathway, any

where from the retina to the occipital cortex •  The location and extent of the visual field loss is

dependent on where the damage occurs along the pathway

• Homonymous hemianopsia: loss of half of the field of view on the same side in both eyes

Visual-Perceptual Impairments • Diplopia (double vision): primary functional disruption

observed in patients with cranial nerve lesions •  3 pairs of cranial nerves control the extraocular muscles:

•  Oculomotor nerve (CN III) •  Trochlear nerve (CN IV) •  Adbucens nerve (CN VI)

•  Affects eye-hand coordination, postural control, and binocular use of the eyes

•  Can occur throughout focal range •  Within 20 inches of face: writing, grooming/hygiene •  Distance (greater than 4 feet): walking, driving

• Unilateral visual inattention/neglect: disruption of visual attention creates asymmetry and gaps in visual information gathered through visual search. •  Driving and reading are often significantly affected by inattention

“Visual Concerns that Interfere with Daily Activities in Patients on Rehabilitation Units: A Descriptive Study”

• Purpose: Estimate # of patients with visual concerns that interfere with ADL’s through OT assessment

• Methods: 215 patients evaluated using the Brief Vision Screen (BVS) through ADL

•  Findings: •  Largest proportion of patients (55%) with visual concerns were

diagnosed with stroke. •  Results consistent with previous literature which suggests visual

impairment is common among patients in rehabilitation units •  Further validation of the BVS is needed

Literature Review

(Grider, S.L, Yuen, H.K., Vogtle, L.K, & Warren, M, 2014)

Brief Vision Screen

“Preliminary Validation of a Vision-Dependent Activities of Daily Living Instrument on Adults with Homonymous Hemianopia”

• Purpose: Validate use of the Self-Report Assessment of Functional Visual Performance (SRAFVP) in patients w/ homonymous hemianopia (HH) to measure ADL limitations

• Methods: 30 patients w/ HH from stroke rated difficulty of visual ability to complete ADL’s on SRAFVP

•  Findings: SRAFVP demonstrates sufficient reliability and validity to evaluate the severity of ADL impairment in patients w/ HH from stroke.

Literature Review

(Mennem, T. A., Warren, M., & Yuen, H. K., 2012)

“Compensatory Strategies Following Visual Search Training in Patients with Homonymous Hemianopia: An

Eye Movement Study”

• Purpose: Characterize changes in oculomotor scanning with addition of practiced visual search in patients with homonymous visual field defect.

• Methods: 31 patients performed visual search training for 20 sessions over 4 weeks

•  Findings: Post training, patients improved search efficiency and quickness with locating targets within their hemispace

Literature Review

(Mannan, S., Pambakian, A., & Kennard, C., 2010)

Key Symptoms to Look for During Eval •  Facial expressions, head turning/

slanting, squinting •  Facial droop •  Ptosis

•  Fatigue, frustration, complaints of headache

• Complaints of losing place when reading

• Quality of eye movements •  Smooth vs. ‘jerky’ movements

• Eye missing or losing targets •  Over or undershooting

Interventions for Visual Field Loss • Patient education • Awareness and safety •  Increase search area and pattern

•  Head and shoulder turning •  Length of saccades

•  Increase sensory awareness • Position items on tray table to affected side • Distinct starting “anchor” point

•  Whiteboard w/ colored tape on L edge •  Colored line on paper

• Have patient walk towards direction of affected side •  Use flashlight aimed in front of each step

Interventions for Unilateral Visual Inattention/Neglect

• Scanning patterns •  Left to right linear pattern for reading and small visual detail •  Left to right clockwise or counter-clockwise pattern for viewing

unstructured visual details • Visual scanning as a “preparatory” task to ADL

participation •  Utilizing patients whiteboard •  Incorporate A&O questions

•  Incorporation of mirror • Encourage people and objects on side of inattention

•  Increase of auditory and visual stimuli on affected side • Partial occlusion

Interventions for Diplopia • Complete vs. Partial Occlusion

•  Complete occlusion: Eye patch •  Partial occlusion: opaque tape on

glasses •  Switch between R and L

• Prisms •  Displaces the image and causes

the disparate images created by the strabismus to fuse into single image

•  Gradually weaned from the strength of the prism

Addition of Cognitive Impairments •  Grade visual intervention up or down •  Case example: Unilateral visual inattention to L

•  Low level cognition: •  Sensory stimulation •  Therapist on L side: follow hand, reach for washcloth

•  High level cognition: •  Grooming/hygiene or meal preparation with all items on L side •  Write in sections of patient’s whiteboard

•  In between •  Mirror for dressing or grooming/hygiene •  MoCA

What other supplies or resources can we utilize that are available in the hospital?

Looking ahead… • Utilize resources:

•  Outpatient neuro rehabilitation •  Referral/recommendation to vision care specialists

•  Optometrist •  Ophthalmologist •  Low vision specialist

•  Literature Review: “Impact of visual impairment assessment on functional recovery in stroke patients” •  Quantitative findings: Visual assessment did not influence functional

recovery •  Qualitative findings: Perceived benefits noted from the vision

assessment service

• Continued research on BVP and SRAVFP assessments

Conclusion

•  Factors impacting conclusion/answer of research question… •  Patient’s short length of stay and limited interactions •  Standardized Vision Assessments •  Complex patient cases including impaired cognition and

communication

References •  Grider, S.L, Yuen, H.K., Vogtle, L.K, & Warren, M. (2014). Visual concerns that interfere with

daily activities in patients on rehabilitation units: A descriptive study. Occupational Therapy in Health Care, 28(4), 362-370. doi:10.3109/07380577.2014.933946

•  Hillier, R., & Tarbutton, N. M. (2014). Vision deficits following stroke: Implications for occupational therapy practice. OT Practice 19(21), 13–16.

•  Jarvis, K., Grant, E., Rowe, F., Evans, J., & Cristino-Amenos, M. (2012). Impact of visual impairment assessment on functional recovery in stroke patients: a pilot randomized controlled trial. International Journal of Therapy and Rehabilitation. 19(1), 11-22.

•  Mannan, S., Pambakian, A., & Kennard, C. (2010). Compensatory strategies following visual search training in patients with homonymous hemianopia: An eye movement study. Journal of Neurology, 257, 1812–1821.

•  Mennem, T. A., Warren, M., & Yuen, H. K. (2012). Preliminary validation of a vision-dependent activities of daily living instrument on adults with homonymous hemianopia. American Journal of Occupational Therapy, 66, 478–482. http://dx.doi.org/10.5014/ajot.2012.004762

•  Pendleton, H. M., & Schultz-Krohn, W. (2013). Pedretti’s occupational therapy: Practice skills for physical dysfunction (7th ed.), St. Louis, MO: Elsevier.

•  Smith-Gabai, H. (2011). Occupational therapy in acute care. Bethesda, MD: The American Occupational Therapy Association, Inc.

THANK YOU!