"The human brain, then, is the most complicated
organization of matter that we know."
- Isaac Asimov
Brain Injury: Vision and Associated Problems
Brain injury can result in a variety of vision problems. Because the optic nerves, optic tracts and motor nerves to the eye run long courses through or under the brain, they can be affected in a variety of manners based on the location of the lesion. The list below includes some of the commonly associated problems in brain injury:
- Hemianopsia (Loss of half of the field of view right or left)
- Quadranopsias (Loss of about 1/4 sector of the visual field)
- Central Loss of Visual Field
- Sectorial Loss of Visual Field
- Peripheral Visual Field Loss
- Total Loss of Visual Field
- Attitudinal Losses
- Reading Disorders
- Double Vision - Exotropia, Esotropia and Hypertropia
- Cranial Nerve Paresis / Paralysis III ,IV, VI , VII
- Dry Eye from Decreased Blink Rate
- Visual Hallucinations - Formed Objects/People
- Visual Hallucinations - Unformed Stars, Lighting Bolts Anisocoria
- Accommodative Problems in Patients under 40 Convergence Problems
- Pseudomyopia due to Spasm of accommodation (focusing)
- Disturbances of Light Photosensitivity - Vision seems too bright
- Disturbances of Dark Adaptation. Vision seems too dark
- Eye Movement Disorders, Fixation, Pursuits
- Unstable Ambient Vision
- Loss of Contrast Sensitivity - Vision seems foggy.
- Visual Perceptual Disturbances, Palinopsia, or Perseveration of an image
- Disturbances in body image Disturbances of spatial relationships
- Hemi spatial In-attention (Visual Neglect)
- Agnosia - difficulty in object recognition
- Apraxia - difficulty in manipulation of objects Memory Problems
- Psychological problems
- Frequent Headaches
Modified from a list by Allen Cohen, O.D. and Lynn Rein, O.D.
Brain Injury with only a Visual Field Defect
A small number of patients present with damage localized to a specific areas of one lobe thus reducing the number of associated problems. The most significant being a small area of stroke isolated to the occipital lobe. This may create a homonymous hemianopsia without cognitive impairment, paralysis, visual neglect, or impaired eye movements. These patients may be candidates to return to higher level functioning including driving with the right rehabilitation.
Unfortunately many of patients fail to receive adequate visual rehabilitation services because they do not present with the severe debilitating problems of hemiparesis, confusion or speech problems that typically lead the patient into rehabilitative services. These patients may have had no hospital stay that might have lead to rehabilitative services.
Case Example: Patient S.W. This patient presented with a dense right homonymous hemianopsia, but no hemiparesis. She was cognitively intact, mentally alert, had no speech or reading problems except for the effect of the visual field on reading. Her visual acuities corrected to 20/20 in both eyes. Her eye movements, focusing and convergence were normal. She demonstrated no visual spatial problems and memory was good. She had received some brief occupational therapy to improve her scanning to the side of the loss. Her only problems were related to mobility with the visual field loss including running into things and being startled by objects suddenly appearing from the right side. Her desire was to return to drive.
This patient may have potential to return to driving, but will require fitting of a visual field expander, additional training of saccadic eye movements to scan into the impaired visual field, followed by behind-the-wheel training with a driving rehabilitation specialist. See our section on driving issues for more information on driving.
Please contact us if you have any questions.
The Low Vision Centers of Indiana
Richard L. Windsor, O.D., F.A.A.O., D.P.N.A.P.
Craig Allen Ford, O.D., F.A.A.O.
Laura K. Windsor, O.D., F.A.A.O.
Indianapolis (317) 844-0919
Fort Wayne (260) 432-0575
Hartford City (765) 348-2020