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Curr Res Concussion Vol 2 No 2 Summer 2015 61
JM Lynch, S Stanley Green. Do the eyes have it? Can consideration
of concussion variants improve management? Curr Res Concussion
A concussion can be considered to be a disorder of information processing.
Concussions are currently viewed as a homogenous condition. The wide
range of signs and symptoms associated with concussion syndromes suggest
there may be variants of subtypes of concussion. The mainstream recom-
mendations for concussion management suggest physical and cognitive rest
on the presumption that decreased stimuli will allow restoration of cellular
homeostasis in the neural tissue. The authors believe that adding computer
gaming glasses to the treatment of concussed patients with prominent
visual symptoms follows the same line of reasoning and will prove to be an
effective management technique. They also suggest that targeted manage-
ment interventions aimed at other prominent symptoms present in a con-
cussed patient may improve recovery.
Key Words: Computer glasses; Concussion; Concussion management; Gaming
glasses; Postconcussion syndrome
Do the eyes have it? Can consideration of concussion
variants improve management?
James M Lynch MD, Sue Stanley Green MS ATC LAT
Concussions have witnessed a remarkable increase in media
attention over the past decade. Concussions are brain injuries
that are considered to be diffuse in nature, rather than focal and
structural. A concussion is a traumatically induced alteration in
brain function (1-4) that can be summarized as a disorder of informa-
tion processing (5). Concussions occur frequently within the sport-
ing arena, with the incidence varying among sports (6). Concussions
are also a common occurrence in occupational settings and motor
vehicle collisions, accounting for a significant number of visits to
There are a variety of symptoms associated with concussion includ-
ing dizziness and vertigo, difficulty concentrating, light sensitivity,
headaches, depression, difficulty sleeping, irritability, word-finding
difficulty, impulsiveness and amnesia (7,8). Difficulty concentrating
and feeling slowed down are often prominent symptoms during the
first week after a concussion (7). The assortment of clinical symptoms
that occur in individuals with concussion or postconcussion syndrome
has not correlated well with the mechanism of injury or the cellular
Concussions have traditionally been viewed as a uniform condi-
tion. In previous decades, health care professionals evaluated the pres-
ence and severity of symptoms at time of presentation to establish the
diagnosis and determine a grade. The grade and history of previous
concussion then established a definitive time period for restriction of
activity. Recent recommendations emphasize the length of time symp-
toms are present, rather than the initial severity, as the crucial factor
in concussion diagnosis and management (1-4).
The constellation of symptoms actually present in any individual is
currently of secondary importance, conveying the perspective of uni-
formity in concussion. Contemporary management is not changed
across the range of symptoms. Complaints of headache versus light
sensitivity, dizziness or depression do not significantly change the
protocol used for management.
The brain is a complex organ, with the various structures accom-
plishing differing functions. The injury forces involved in concussions
have unique vectors that may traverse different parts of the brain. The
variety of symptoms in concussion and postconcussion syndromes has
sparked consideration of subtypes in both conditions and prompted
attempts to categorize symptoms into groups (8-11). These subtypes are
most commonly grouped into some version of three categories: cogni-
tive, somatic and emotional/behavioural symptoms (8-10). Subsequent
treatment may be tailored to the particular symptom complex or clas-
sification an individual patient is experiencing. Our group believes the
treatment of visual symptoms will be one of these differentiations.
PATHOPHYSIOLOGY AND NATURAL HISTORY
Cerebral concussions involve a cascade of metabolic changes that occur
at the cellular level of the brain (12). The initial injury causes a change
in membrane permeability, resulting in abnormal distribution of ions
across the axon and excessive excitatory neurotransmitter release. The
restoration of normal ion and neurotransmitter distribution requires a
great deal of cellular energy from ATP to power the sodium-potassium
pump. This requires increased glucose metabolism to support the accel-
erated energy demand (12).
Other cell components begin to malfunction later in the cascade.
Increased intracellular calcium concentration results in mitochondrial
dysfunction, worsening the energy crisis. The calcium increase also
disrupts neurofilaments and microtubules, impairing neural connectiv-
ity (12). The altered cellular homeostasis accompanies the energy
imbalance (13). As clinical symptoms resolve, it can be presumed that
cellular homeostasis is re-established. Postconcussion syndrome may
occur with a failure to restore homeostasis.
Symptoms generally resolve within 21 days, with the majority of
concussions resolving in seven to 10 days (13,14). Adolescent athletes
appear to experience a longer recovery time than mature athletes (14-
16). A significant percentage of patients diagnosed with concussions
experience persistent symptoms (13,17). Ten percent to 20% of con-
cussed patients experience symptoms that last >2 weeks, whereas
approximately 2% experience symptoms that last weeks to months
(18,19). The incidence may be higher in emergency room patients
presenting with concussion (20).
Visual symptoms are included in one of the three categories often
used to describe the proposed subtypes of concussion, although visual
symptoms may be placed in the cognitive or somatic category (21-26).
The visual system is located throughout the brain, from the retina and
optic chiasm anteriorly to the occipital lobe posteriorly, with several
crucial structures in between. Injury forces are likely to involve some
of the numerous components of the visual system. Visual changes,
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Florida Southern College, Lakeland, Florida, USA
Correspondence: Dr James M Lynch, Florida Southern College, 111 Lake Hollingsworth Drive, Lakeland, Florida 33801, USA.
Telephone 863-680-6205, fax 863-680-4251, e-mail email@example.com
Lynch and Stanley Green
Curr Res Concussion Vol 2 No 2 Summer 201562
including increased photosensitivity and photophobia, have been
reported in concussion patients (21-26). A high incidence of visual
dysfunction has been reported in soldiers who sustain mild traumatic
brain injury (mTBI) following blast injuries (25). Vestibular ocular
dysfunction has also been noted in a large percentage of sport-related
The diagnosis of concussion was made through clinical examination
historically. Neuropsychological means have been added to the regi-
men over the past couple of decades. Balance testing gained popularity
with the Balance Error Scoring System test (28). Inroads have been
made with identifying serum biomarkers associated with concussion,
although this remains in its infancy (29).
A brief vestibular ocular assessment was able to differentiate
between concussed and nonconcussed patients (27). The increasingly
popular King-Devick test uses a simple timed test to assess visual sac-
cades as well as concentration and language function in patients with
concussions (30-32). Eye tracking technology has been shown to be
accurate in detecting third and sixth cranial nerve palsies in brain
injured patients (33). There is not yet documentation of the utility of
eye tracking in concussion but the prevalence of identified dysfunc-
tion (21-27) suggests that eye tracking technologies will be helpful.
Treatment options for concussion are limited (34), with mainstream
recommendations emphasizing physical and cognitive rest (14). There
is some question as to the necessity or efficacy of prescribed rest
(16,35,36). A recent report with a strong research design (36) suggests
that more rest is not better. Other therapies have had limited efficacy
and/or have had limited research designs. The more successful treat-
ment strategies have focused on a particular symptom complex (34).
Our group recently reported two adolescent athletes suffering post-
concussion syndrome with debilitating symptoms of one years’ dur-
ation, which adversely affected both academic and sports activity (5).
The dominant symptom complex in each involved the visual system.
Both patients began using computer gaming glasses (Gunnar Optiks,
Inc, USA) with resolution of symptoms (5). We have subsequently
used the gaming glasses with success in three of four collegiate athletes
with prominent visual symptoms following a concussion.
The brand of glasses (Gunnar Optiks) we chose appeared to have
the highest quality with the best pricing (Figure 1). The frame style
was left to each patient’s preference to increase the likelihood of use.
This brand of computer gaming glasses has a patented amber tint that
filters nearly 100% of blue light at 400 nm to 45% of blue light in the
450 nm wavelength. Blue light in the 400 nm to 450 nm wavelength
range activates s-cones in the retina. The focal area of the lens has a
flatter and wider midpoint, lessening the need for accommodation
(focusing) at a distance of 51 cm to 61 cm (20 in to 24 in), the typical
viewing distance for a computer monitor.
The present report provides an interesting suggestion but does not
constitute a definitive recommendation. We believe additional data
from a variety of researchers are necessary to determine whether the
use of computer gaming glasses is a reasonable recommendation for
concussion management on a larger scale.
The incidence of visual dysfunction in concussion has a strong base
in the literature (21-27); however, additional work specifically
addressing sport-related concussion will be useful. Investigation of the
particular types of visual dysfunction should also be addressed in future
studies. Vestibulo-ocular deficits (27), oculomotor deficits of vergence,
version and accommodation (alignment, tracking and focusing) (25)
have all been demonstrated previously. Abnormalities in visual sac-
cades are the premise underlying the success of the King-Devick test
(30-32). Functional magnetic resonance imaging in the presence of
these abnormalities will provide some fascinating data. The efficacy of
computer gaming glasses should be evaluated in a randomized con-
trolled trial of concussed patients with visual symptoms.
We also believe the same principles can be applied to other prom-
inent symptoms of concussion to improve management. An obvious
example is the use of noise-cancelling headphones in patients who
demonstrate noise sensitivity.
The mainstream recommendations for concussion management sug-
gest physical and cognitive rest on the presumption that decreased
stimuli will allow restoration of cellular homeostasis in the neural tis-
sue. We believe adding computer gaming glasses to the treatment of
concussed patients with prominent visual symptoms follows the same
line of reasoning and will prove to be an effective management tech-
nique. We also suggest that targeted management interventions aimed
at other prominent symptoms present in a concussed patient may
DISCLOSURES: The authors have no financial disclosures or conflicts
of interest to declare.
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Figure 1) Gaming glasses (photo courtesy of Gunnar Optiks, Inc, USA)
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