Does 20/20 visual acuity ensure you can see a 3-ring circus?
What do we see in the picture?
What do we see now?
Hence, Visual recognition is more than just detail detection. The visual brain is more than the eyes and occipital lobe.
Vision is more than acuity:
1. Vision is a process
2. Good vision requires the effective input of visual information
3. Good vision requires the effective processing and integration of visual information
1. Vision: Input Abilities
a. Binocular control: Ranges of fusion and integration with accommodation
b. Accommodative control: Amplitude, flexibility/facility and integration with binocular control
c. Oculomotor control: Fixations, pursuits and saccades
2. Vision: Information Processing
a. Visual-Spatial Orientation:
Laterality and Directionality
b. Visual Analysis Skills:
- Visual Discrimination
- Visual Figure Ground
- Visual Closure
- Visual Memory and Visualization
3. Vision: Integration Process
a. Visual – Motor Integration
b. Visual-Vestibular Integration
c. Visual – Auditory Integration
d. Visual-Verbal Integration
The Vision helps in many ways as it:
1. Plans and guides our effective movement
2. Substitutes for our need to move/touch to gather information
3. Is the dominant sense in human cognition by organizing, interpreting, understanding, storing and recalling information
4. Is the foundation for imagination: An imagery!
Thus, vision is something that is learned and it’s a developmental process indeed. Recent evidence shows the existence of a visual syndrome that can often elude detection but causes significant impairment. The visual syndrome affects a significantly high percentage of children and adults. It impacts reading and learning performance, it is often associated with behavioural/emotional problems. It has little or no impact on distance visual acuity leading to false negatives on acuity- based vision screenings.
BAOD Vision Syndrome: The vision triad that causes impairment are:
BAOD Syndrome: The vision dysfunction that causes impairment
The common signs and symptoms profile of BAOD Syndrome are:
- Struggling in reading efficiency
- Headaches, eye strain, words overlap
- Frustration with sustained close work (ex: homework)
- Poor attention/concentration (ADD-like behaviours)
- Poor memory/comprehension
How to manage? Steps:
1. Begin to look for the BAOD Syndrome symptom profile in all patients, especially children with the aforementioned signs and symptoms.
2. Check for some of the key clinical findings to make the Diagnosis:
a. Reduced Near Point of Convergence
b. Excessive Exophoria or Esophoria at near
c. Reduced Positive Fusional Vergence
d. Low accommodative abilities (PRA, NRA or Facility)
e. Poor oculomotor skills (pursuits, saccades, fixations)
3. Direct a plan of patient management:
a. Provide office-based, doctor supervised optometric vision therapy or…
b. Refer to a colleague who specializes in developmental vision and vision therapy care and provides competent office-based, doctor supervised optometric vision therapy
BAOD Case Management in a VT Practice (Flowchart)
- Initial comprehensive diagnostic vision evaluation
- Assessment of visual information processing
- Management / Treatment
– Doctor supervised office-based VT (OBVT)along with home activities. Patient sessions 1-2 times per week
– Periodic progress evaluations with the doctor
– Exit evaluation with the doctor to confirm patient has reached automaticity in visual function
– 3 month post vision therapy evaluation with the doctor to verify patient has maintained visual function
Benefits of treating BAOD
- You will be appreciated by your patient – they will experience greater success through better vision
- You will be appreciated by your patients family and the community…as a doctor who really cares
4. Applied Concepts in Vision Therapy. Press LJ. OEPF 2008
5. Binocular Anomalies: Diagnosis and Vision Therapy (4th ed.)Griffin, JF, Grisham JD, Butterworth-Heinemann 2002
6. Clinical Management of Binocular Vision: Heterophoric, Accommodative, and Eye Movement Disorders Scheiman M. Wick B. Lippincott 2008.