Concussion and Acquired Brain Injury (ABI)
The Concussion Crisis: A Silent Epidemic of ABI
Leonard J. Press, O.D., FCOVD, FAAO
We normally think of concussion as related to direct trauma to the head. Increasingly common in sports injuries at younger ages, concussion with significant sequelae has now been widely recognized in college football, even at the high school level and younger. I wrote about this earlier in the year, as related to use of the King-Devick Saccade Testas a remove-from-play sideline screening tool, and it has gained more momentum of late. The cumulative effect of concussions on the brain and the death of neurons on cognitive function has drawn increasing attention.
A new book by Carroll and Rosner makes several excellent points regarding the silent epidemic. The first is that children with mild TBIs often fall through the cracks. They have subtle impairments in short term memory and eye-hand coordination among other deficits, and teachers are quick to assume these children aren’t trying hard enough. The second is that even when tests of subjective cognitive function don’t show the child to be appreciably impaired, objective measures of brain function such as the EEG can be insightful. (Though the book doesn’t address this, there is evidence that the P1 latency of the VEP is delayed in a significant proportion of individuals with cerebral concussion.) Third, there are concussions that children experience without a direct blow to the head. Shaken baby syndrome is a classic example. Lastly, the development of the ImPACT test, the Immediate Post-Concussive Assessment and Cognitive Testing by Lovell and colleagues, is described in detail.
Lovell is featured prominently in the case of Angelica Kruth, a teenager who smashed her chin on the floor during cheerleading practice. Her mother took Angelica to the pediatrician who diagnosed a swollen jaw and whiplash, treating her with ice packs and painkillers. X-rays and CT scans of her jaw were normal. A straight-A student, Angelica couldn’t focus in class. Her vision was so blurry that she couldn’t read. Her mother waited another two weeks for an appointment with Lovell who, upon learning of her symptoms administered the ImPACT test, and was not surprised to see her struggle with it. Her scores on mental processing speed and memory were reduced to the 5th percentile for her age level. He reassured her mother that with a month or so of rests most kids got significantly better. For those that didn’t there were promising drug treatments and newly developed rehabilitation techniques. After a month, things were no better. Lovell began experimenting with medications to improve Angelica’s migraines so that they could go to work on her vision.
At first, her vision was so impaired that if a page contained even a single word, like “cat”, she could tell that there were letters but she couldn’t make out what they spelled no matter how large they were. The harder she tried to read the word, the harder her head would pound. To help her relearn to focus her eyes, therapists used moving targets to help her converge and diverge. In another exercise she was told to look at a word on the wall and turn her head from side to side without taking her eyes off of it. What the authors of The Concussion Crisis, Carroll and Rosner are describing here, is part of Vestibular Rehabilitation Therapy, in particular gaze stabilization therapy. The focus of these exercises is primarily to address re-integration and restore the gain of the vestibulo-ocular reflex, and the following videos from the University of Michigan are representative.
While I welcome Carroll and Rosner’s book for its inclusion of VRT exercises, this approach can and should have been complemented by a neuro-optometric vision evaluation. Angelica’s progress as reported was painstakingly slow, and she was left with residual deficits that may have been helped further, or at least a recovery that might have been accelerated through optometric consultation as outlined by our colleague, Dr. Dan Fortenbacher, in his approach to Neuro-Ocular Vestibular Dysfunction, or the See-Sick Syndrome. Too many patients like Angelica are left with impaired visual functions as described by Dr. Fortenbacher. Orientation and movement may be affected, as well as abnormalities in which print looks like this, either initially or after just a few minutes of reading:
Whether through lenses, prisms, filters, or other forms of vision therapy, patients like Angelica should be given the opportunity to benefit from optometric consultation. To overlook this compounds the silent epidemic.