Michael Cole, OD, Child and Family Eye Care Center
Traumatic brain injury (TBI) can have a profound effect on those unfortunate enough to experience it. Many systems in the body are thrown into disarray and often it becomes a long road to recovery before one starts to feel comfortable again. In our clinic, we have treated vision concerns for a wide variety of injuries ranging from concussions in sports, car accidents, strokes, military service, gunshot wounds, and even a lightning bolt to the head! There unfortunately seems to be a never-ending list of possibilities for a brain injury, and thankfully we have been able to aid in recovery for these patients.
In all, close to 70% of post-TBI patients have vision diagnoses. This does not, however, mean that these patients see an increase in blurry vision or need a new glasses prescription. Rather, these patients struggle with other aspects of vision that may go untreated if they are not evaluated properly. Routine eye examinations that evaluate eye health and visual acuity alone will not be adequate to identify these problems when they exist.
The most common visual complaints are accommodative disorders. Accommodation refers to the ability of our eyes to change focal distances. Much like a camera lens, our eyes can change focus to view objects at different distances. Post-TBI patients often find themselves unable to read or otherwise see clearly up close like they were able to prior to sustaining the injury. This ability can be restored with time and training, and sometimes requires the use of additional corrective lenses to aid in the short term before recovery can commence.
Around half of patients experience convergence insufficiency, or the inability to adequately aim both eyes at a near target. Without a strong convergence system, it is difficult to perform near tasks without double vision. Often patients will complain of tired, achy eyes and frequent headaches. Many are unable to continue hobbies such as reading or sewing due to the excessive strain and poor vision. It is our pleasure to aid in the return to such activities and a normal life for these individuals.
Sometimes eye movements are affected after brain injuries. Depending on the area of the brain that is hurt, different types of eye movements can be impaired. Some patients have damage to the saccadic control areas which plan high-speed positional changes of the eyes to new locations. This is the type of motor movement used when reading or changing gaze to look at a new target of interest. Different areas of the frontal lobe plan smooth movements, called pursuits that allow us to follow a moving object without losing our aim. It can be very frustrating for patients unable to initiate or accurately carry out these basic functions of vision. Fortunately, this too can be improved with rehabilitation.
In cases of severe injury to specific areas of brain tissues, sometimes different areas of our visual field are lost. For example, an injury to the occipital lobe can cause a complete loss of vision on one side of our vision. This would mean that one could see clearly straight ahead and to one side of peripheral vision. The other side of the periphery, however, could be completely lost. Patients such as these often need vision aids and training to help them navigate the world due to the now unseen portions of their vision.
Unfortunately, all too often these patients struggle with these vision concerns without treatment. If you or a loved one is in need of help in this area, please schedule a consult with our clinic.