Homonymous Hemianopia: Rehabilitation with Scanning and Expansion Prism Therapy

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Homonymous HemianopiaRehabilitation with
Scanning and Expansion Prism Therapy

• Kasey Suckow, OD
• Resident Ocular Disease / Low Vision Rehab
• Hines Jesse Brown VA ChicagoAAO Meeting
• Tampa 2007

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Homonymous hemianopia

• Common etiologies
• Stroke (most common1)
• 8.1 over 652
• 20-30 with VF defects3
• Traumatic Brain Injury
• Signature injury
• Lesions along visual pathway

1. Zhang, Xiaojun MD, et al. J Neuro-Ophtho
September 2006 180-183. 2. Neyer, et al.
Prevalence of Stroke 2005. JAMA. July 2007
279281. 3. Rossi PW, et al Neurology
1990401597-9
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Therapy

• Therapy goals
• Increased Awareness
• Increased Visual Field
• Therapy Options
• Scanning Therapy
• Prism Therapy
• Yoked prism
• Expansion prism

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Scanning Therapy

• Never go where your eyes have not gone
• Critical for orientation and mobility
• Pt safety

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Basic Movements

• Head Posture
• Turn towards side of defect
• Field shift
• Eye movements
• Constant scanning
• Systematic movements
• Walking

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Scanning and Turns

• Turning into defect
• Stopping in place
• 90 degree turn
• Scan into defect
• Looking up and down

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Complex environments

• Combining all individual skills.
• Coordinated, intentional movements
• Encourage pt to take their time

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Expansion Prism Therapy 4. Peli, Eli MSc, OD,
FAAO. Optometry and Vision Science. Sept 2000
453-464.

• Increased field of view
• Peripheral prism
• 8 x 22mm segments
• 40 Diopter fresnel
• Monocular fit
• Superior and inferior
• Peripheral diplopia
• Clear single central vision

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Field Expansion 4. Peli, Eli MSc, OD, FAAO.
Optometry and Vision Science. Sept 2000 453-464.
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Expansion Prism Therapy 4. Peli, Eli MSc, OD,
FAAO. Optometry and Vision Science. Sept 2000
453-464.

• Monocular fit (on side of VF defect)
• Upper segment first
• Demonstrate increased field
• Training
• Cleaning and care
• 2 wk adjustment
• Lower segment
• 2 wk adjustment
• Prism ground into lens

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Pt Education A.R. Bowers, et al. IVOS September
200647 E-Abstract 3489

• Viewing through carrier lens
• Increasing peripheral awareness

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Increased awareness
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Prism Adaptation A.R. Bowers, et al. IVOS
September 200647 E-Abstract 3489

• Image jump
• 10-15 degrees
• Adaptation
• 75 acceptance rate

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Case 1

• 67 WM with hx of recent stroke
• HH confirmed with HVF
• VA 20/25 OD, 20/20 OS
• No head turn/abnormal posture
• Functional complaints
• Bumping into people/objects on his left
• Difficulty avoiding objects on left
• Problems shaving left side of face
• With actual act of shaving
• Difficulty cooking

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Therapy and Response

• Scanning therapy following previously listed
  steps shows increased performance and subjective
  improvement.
• Expansion Prism Therapy also has positive
  subjective results with both upper and lower
  prism.
• Pt notes increased awareness and avoidance of
  objects on left side.

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Case 2

• 74 WM with history of head trauma (gunshot wound
  50 yrs prior)
• HH confirmed with HVF
• VA 20/40 OD, 20/32 OS
• Left head turn
• Significant fall history
• Functional complaints
• Pt did not have any complaints, but interested in
  prism therapy for increased left awareness.

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Therapy and Response

• Scanning therapy shows pt is proficient and has
  developed good compensating skills.
• Pt notes improved awareness of field, but not
  enough improvement to warrant permanent lenses,
  and preferred habitual Rx alone.

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Differences between Pts

• Case 1
• Relatively recent loss
• No head turn
• Poor scanning strategies
• Several Functional complaints

• Case 2
• Long term loss
• Left head turn
• Good scanning strategies
• Few functional complaints

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Conclusions

• Benefits of Scanning and Prism Therapy
• Safety
• Street crossing
• Fall prevention
• Orientation and Mobility
• Increased Confidence
• Each pt unique
• Consider patient goals and motivation
• Successful rehabilitation involves therapy with
  or without prism.

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Acknowledgements

• Steve Rinne, MA Low vision research therapist
• Amy Wurf, MA Low vision therapist
• Joan Stelmack, OD MPH