Visual Restoration for Hemianopia

Inclusion Criteria:

- Ages 21-75 years old

- Ability and willingness to sign informed consent

- Willingness to participate in both the training and evaluation sessions

- MRI or CT scan demonstrating lesion in the occipital lobe of the brain and/or
affecting white matter tracts that provide visual input to the occipital lobe of the
brain

- Brain injury due to ischemic or hemorrhagic causes that occurs after age 18 and at
least 90 days prior to screening visit

- At least two reliable HVF's demonstrating good fixation and a stable homonymous
incomplete (e.g., quadrantanopia or relative defect) or complete hemianopia

- Reliable HVFs with repeat HVFs if randomization takes place more than 4 weeks after
screening visit

- A homonymous, contiguous visual deficit measured by the 24-2 HVF to be a minimum of
two testing locations high and two testing locations wide, where impaired locations
are any that measure a threshold of less than 15 dB.

- Demonstration of good fixation on visual training task - able to fixate the small
targets presented as fixation letters reliably for 1000ms with jitter over less than 1
degree of visual angle in any direction away from target edge

Exclusion Criteria:

- Physical, neurological or mental disability that would interfere with study
intervention

- Concurrent participation in "vision therapy" other than standard occupational or
physical therapy

- Unreliable visual fields on prior testing, indicated by greater than 20% fixation
losses, false positives, or false negatives.

- Inability to discontinue medications judged to affect training and/or assessment
(e.g., Ritalin, amphetamines, dopamines, or chemotherapeutic agents)

- Physical condition likely to preclude completion of the clinical trial (e.g. end-stage
or uncontrolled cancer, uncontrolled epilepsy, or end-stage heart disease)

- Ocular or neurological condition that would interfere with training or assessment
(e.g. damage to the optic nerves or lateral geniculate nucleus, any degenerative
ocular condition)

- Best corrected vision worse than 20/40

- Impaired foveal Humphrey sensitivity as indicated by the HVF tests.

- Presence of vision loss resulting from ocular disease or disorder

- Presence of bilateral visual acuity loss from any source

- Inability to demonstrate fixation stability on eye movement monitored testing

- Inability to follow training instructions