Incidence and Treatment of Visual Dysfunction in Individuals with Brain Injury

Author/ Year/ Country/Study Design/N

Methods

Outcome

Conrad et al. (2016)
USA
Pre-Post
NInitial=19, NFinal=13

Population: TBI=15, Stroke=3, Organic Brain Syndrome=1; Mean Age=45.2yr; Gender: Male=12, Female=7; Time Post Injury=2.2yr.
Intervention: Participants were prescribed home-based computer vergence therapy using software provided (5d/wk for 12wk). Participants were assessed at baseline, 4, 8 and 12wk. 
Outcome Measure: Negative Fusional Vergence, Positive Fusional Vergence, Near Point of Convergence, Vergence Facility, and Convergence Insufficiency Symptom Survey (CISS).

 

 

 

  1. Negative fusional vergence showed significant improvement over 12wk in blur (p=0.037), break (p=0.003) and recovery (p=0.006).
  2. Positive fusional vergence showed significant improvement over 12wk in blur, break and recovery (p<0.0001).
  3. Near point of convergence showed significant improvement over 12wk in break (p=0.002) and recovery (p<0.001).
  4. Vergence facility showed a significant improvement from baseline to 12wk (p<0.0001).
  5. CISS scores improved significantly from baseline to 12wk (p=0.0001).

     

Doble et al. (2010)
USA
Pre-Post
N=43

Population: TBI; Mean Age=44yr; Gender: Male=12, Female=31; Meant Time Post Injury=3.6yr.
Intervention: Patients were given individualized prismatic spectacle lenses.
Outcome Measure: Vertical Heterophoria Symptom Questionnaire (VHS-Q).

 

 

  1. The mean VHS-Q score at baseline was 34.8 ±16.1 (scale ranges 0-75 points).
  2. The mean difference in VHS-Q scores pre to post intervention was 16.7 ± 12.8 (p<0.01). 

 

Ciuffreda et al. (2006)
USA
Non-RCT
N=14

 

Population: TBI=9, Stroke=5; Mean Age=48.4yr; Gender: Male=9, Female=5; Mean Time Post Injury=2.4yr.
Intervention: Reading-related rehabilitation in patients with an oculomotor-based reading dysfunction. Participants were assigned to either Visual (V) Feedback Training (modes included normal internal oculomotor visual feedback in isolation - T1 for 4 weeks) or combined Visual and Auditory (V+A) Feedback (concurrent with external oculomotor auditory feedback - T2 for 4wk) with a cross-over design. Single-line (SL) and multiple-line simulated reading, and basic versional tracking (fixation, saccade, and pursuit) 2x/ wk for an 8wk period.  
Outcome Measure: Simulated Reading, Visagraph, Basic Versional Eye Movements, and Reading Rating Scale.  

 

  1. Significant improvements were found for each of the five questions on the reading rating scale (p<0.01).
  2. Simulated reading saccade ratio showed significant improvements for ML (TI: p<0.05) and SL (TI: p<0.01; T2: p<0.01)  training compared to pre-training levels
  3. TBI subgroup had more improvements in the simulated reading and Visagraph.
  4. There was a trend (0.05 <p< 0.10) for greater reading improvement in V+A Feedback training.

 

 

Kasten et al. (2000)
Germany
RCT
PEDro=5
N=32

 

 

Population: Vascular Disease=9, ABI=23; Mean Age=51.1yr; Gender: Male=20, Female=12; Mean Time Post Injury=6.8yr.
Intervention: Randomly assigned to either the Control Group (foveal fixation training only - FixTrain) or Restitution Group (PC-based training program – Visure, SeeTrain). Both groups trained for 1hr/d at home for ≥150hr over a 6mo period. 
Outcome Measure: High-Resolution Campimetry (PeriMa), Conventional Perimetry (TAP-2000), Pattern Recognition (PeriForm), and Colour Discrimination (PeriColor).

 

  1. The restitution group showed an increase in PeriMa and TAP-2000 after training (p<0.01; p<0.04 respectively).
  2. The restitution group had non-significant improvements in PeriForm and PeriColor (p=0.06; p=0.12 respectively) within the defective area of the visual field.
  3. There was a correlation between PeriMa and PeriForm (r=0.67, p<0.05) and PeriForm and PeriColor (r=0.37, p<0.05) for improved color and form perception.
  4. The PeriMa, PeriForm, and PeriColor all demonstrated a shift of the visual field border in the direction of the blind area for subjects in the restitution group.
Kasten et al. (1998)
Germany
RCT
PEDro=7
N=38

Population: Stroke=10, ABI=28; Mean Age=51.5yr; Gender: Male=24, Female=14; Mean Time Post Injury=7.0mo.
Intervention: Randomly assigned to either the Restitution Group (visual restitution training (VRT)) or the Control Group (fixation training program which required eye movement toward stimuli within the foveal region). Both groups completed 150hr of training over 6mo at home in a darkened room. 
Outcome Measure: High-Resolution Perimetry (HRP) and Tübinger Automatic Perimeter 2000 (TAP).

 

  1. Performance on HRP showed improved ability to perceive visual stimuli above detection threshold in the VRT group post-training (post-chiasmic: p<0.05, optic nerve: p<0.01).
  2. The VRT group demonstrated a higher response frequency to stimuli than the control group (p<0.05).
  3. TAP scores showed decrease in the area of absolute defect for subjects in the VRT group with optic nerve injuries (p<0.01).
  4. Subjects with optic nerve damage benefitted most from VRT; 72.2% of subjects who received VRT reported subjective improvement while only 16.6% of the control subjects did so (p<0.03).
Padula et al. (1994)
USA
Case control
N=20
Population: TBI=10, Control=10; Age Range=22-46yr; Gender: Male=8, Female=12.
Intervention: Visual evoked potentials (VEP) were performed using Nicolet Compact Four Electrodiagnostic System and a Visual Stimulator over three trials. During the baseline trial, subjects were tested without bi-nasal occluders and base-in prisms. In the experimental trial, subjects were tested with bi-nasal occluders and two diopters of base-in prisms. In the last phase, the bi-nasal occluders and prisms were removed and the subjects were re-evaluated.
Outcome Measure: Visual Evoked Potentials.
  1. The use of base-in prisms and bi-nasal occluders produced a large increase in VEP amplitude in the experimental group (p<0.01).
  2. Using base-in prisms and bi-nasal occluders resulted in a significantly larger increase in the experimental group than the control (mean difference between groups 1.78, p<0.01).