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Rehabilitation Tool for Traumatic Brain Injury Patients
Erwin Yap1, David Weinberg1, Dr. Joseph Cheng2
Department of Biomedical Engineering1, Vanderbilt University, Nashville, TN, USA
Vanderbilt Medical Center2, Department of Neurosurgery, Nashville, TN, USA
Introduction:
Traumatic Brain Injury is defined as damage to the brain resulting from external mechanical
forces. TBI is often caused by the rapid coup-contrecoup motion of the brain. This motion causes
neurons in the brain to both stretch and contract. This causes cells to rupture, resulting in “diffuse
axonal shearing”, which tends to occur in the
region between the white and gray matter of the
brain and causes deficiency in communications
between the prefrontal cortex, parietal lobe and
cerebellum (Maas, 2008).
TBI is one of the major causes of
disabilities and deaths worldwide. In fact, 1.4
million people are affected annually in the US; 50,000 die; 235,000 are hospitalized; 1.1 million go
through extensive rehabilitation therapy; 5.3 million Americans currently have a long-term need for TBI
rehabilitation or treatment. The most common causes of TBI occur from falls (28%), car accidents (20%),
assaults (11%) and struck by events (19%). All age groups are vulnerable of experiencing a TBI (CDC.gov).
The degree of TBI damage is classified between mild, moderate and severe. Executive skills are
most commonly impacted in mild TBI. These skills involve a number of fundamental abilities that allow
an individual to appraise a problem, formulate and initiate a plan of action. Thus, sufferers experience
1
Figure 1: Statistics showing the common causes of TBI (cdc.gov)
symptoms of weaken comprehension, communication problems, decreased short-term memory,
attention deficit and loss of sequencing skills. In most cases, patients with mild TBI recover fully.
Patients with moderate TBI deal with weak attention span, chronic memory loss, processing
sensory inputs and emotional problems. They experience loss of consciousness of between 30 minutes
and 24 hours after the injury and oftentimes, they do not remember the event that caused the injury.
Approximately 60% of moderate TBI patients will make a positive recovery and an estimated 25% will be
left with a moderate degree of disability.
Severe TBI patients experience a loss of consciousness that could last days, weeks or months or
even years. The greater the amount of damage, the longer the person remains in coma. Only 25 to 33%
of these patients have positive outcomes and about 33% of these patients do not survive (Rao,2000).
TBI is a common injury of the recent “Global War on Terror.” The Defense Department
estimates that 6 out of 10 soldiers have suffered TBI during the war. During war, most of the brain injury
is caused by bullets or shrapnel hitting the head and the neck. It can also be caused by mortar or
roadside blasts (Iraq War, 2008). According to Dr. Pamela Drury, neuropsychologist of the Vanderbilt VA
hospital, most of the problems experienced by war veterans are navigation and sequencing. Some issues
are caused by the physical aspect of the war while others obtain it due to emotional distress. According
to her, whatever the cause is, it is a problem that ‘needs a solution’. In 2009, the United States
Department of Defense passed a bill, which provides $300 million for TBI research and treatment.
There is currently no quick way to treat TBI. Most treatments are rehabilitation procedures that
could take weeks, months or even years to complete. The goal of rehabilitation is to help the individual
progress to the most independent level of functioning possible. Therapy will focus on regaining lost skills
as well as learning ways to compensate for abilities that have been permanently changed because of the
brain injury. Cognitive rehabilitation is a systematically applied set of medical and therapeutic services
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designed to improve cognitive functioning and participation in activities that may be affected by
difficulties in one or more cognitive domains (Grealy, 1999). Current examples of TBI rehabilitation tools
are paper manuals, making task lists, practical exercises, using a datebook or PDA as a reminder, use of
visual simulation, special watches and rehabilitation classes.
At the Vanderbilt Veteran Affairs (VA) Center, they currently have a rehabilitation class utilizing
the CogSMART program. The CogSMART program is created by the Center of Excellence for Stress and
Mental Health of VA San Diego Healthcare system (See Appendix, page xxxix). Each class consists of
approximately 5 patients with TBI talking about their problems and participating in social activities with
other participants of the class. They need to attend a “class” session once a week which involves a
different lesson per week. They have a workbook which contains writing assignments and questions to
stimulate their brain processing skills regarding the lecture. Participants receive homework so they can
continue their therapy at home.
Another important concept our design incorporates is “chunking.” The human working memory
is known to be able to remember up to approximately 7 items at once, on average. Chunking is the
ability to cut down on the total number of items you have to remember by grouping items together. For
example, take the phone number 1-800-888-4823. There are a total of 11 numbers, but it is possible to
chunk the three 8’s together, since there are all 8’s before the last four numbers. Also, the 1-800
sequence can be chunked as one item since it has already been stored in the long term memory.
Figure 2: Summary of the concept of chunking
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1 8 0 0
8 8 8
4 8 2 3Chunking
1-800 888 4
8 2 3
Project objective:
The objective of our project is to create an open source 3D virtual rehabilitation tool to help improve
working memory function of mild TBI patients.
Goals:
1. Create a virtual rehabilitation interface accompanied by an equivalent hardware model.
2. Implement a neuro-rehabilitaion evaluation tool to measure the extent of TBI injury and analyze
the patient’s strengths and weaknesses by providing feedback.
3. Help TBI patients regain competence in the job market by guiding them to regain executive
skills.
4. We want to know if there will be a difference in chunking performance for the 7-step versus the
10-step groups.
The use of virtual rehabilitation had been tested in several studies; however, no full module
currently exists on the market or the medical industry. Several studies tested the theory that virtual
rehabilitation can be beneficial to learning. Two publications showed that the use of virtual
rehabilitation tool on traumatic brain injury patients proved to be beneficial. According to Madeleine
Grealy’s publication, “Improving Cognitive Function after Brain Injury: The Use of Exercise and Virtual
Reality”, patients with cognitive difficulties were asked to steer to directions or participate in a race
while in a virtual bike. Significant improvements were observed in learning, both auditory and visual, as
well as the digit symbol test compared to the people not using the bike (Grealy, 1999). In another
experiment, “Tasks Performance in Virtual Environments used for Cognitive Rehabilitation after
Traumatic Brain Injury” by Charles Christiansen, a virtual kitchen was developed in which a meal
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preparation task involving multiple steps could be performed by TBI patients. The experiment was
repeated twice with the same group of patients. The total score during the 2nd trial is higher which
means patients improved cognitive functions after the 1st trial.
According to Dr. Pamela Drury, most soldiers coming back from the war are very young, mostly in
their 20s-30s. They prefer using a computer rather than doing paper exercises. By implementing a virtual
rehabilitation tool, it will help engage patients to participate in rehabilitation programs by stimulating
their interests.
Methodology:
Alice Virtual Rehabilitation tool:
Alice is an educational program developed by Carnegie Mellon University that teaches students
computer programming in a 3D environment. We designed our virtual rehabilitation tool around Alice,
for its low resource requirements and because it is open source.
Figure 3: QFD showing the design indicators used for the creation of the Alice 3D world Rehabilitation Tool
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We did not incorporate any special effects or animations because it could cause confusion and
anger to the patient. We also did not incorporate any textures for structures and objects that resemble
the war to prevent memories.
We created a rewards system like a “great job!” and “congratulations!” messages with a fun
little spin animation at the end of the sequence tutorial to give encouragement. We utilized a flash timer
(start, stop, reset functions). We created two difficulty levels: 7-step (cheeseburger) and the 10-step
(table setting). No sound was used to limit distractions.
Hardware equivalent:
We created an actual prototype for both the 7-Step and 10-Step sequences that imitates the
Alice virtual rehabilitation tool design. The 7-Step prototype is made with felt (velvet) materials
purchased from Michaels Arts and Crafts store, which were sown together with a thread and needle.
For the 10-step prototype, we purchased plastic plates, forks, knives, napkins, cup, and small
salad plastic plates from Target.
Testing:
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healthy male college students aged 18-22 were scheduled at least a week prior to the trial date to test
the prototype. They were randomly assigned to four groups as part of a 2x2 factorial design.
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Figure 4: Screenshots of the 7-step sequencing for the Alice Virtual Rehabilitation Tool
Figure 5: Factorial design for testing
Participants arrived on their scheduled dates, and filled out the consent forms. They are asked
to complete either the 7-step or 10-step experiments depending on their groups, and they are timed as
well as checked for number of accuracy and number of sequencing errors.
We prepared a consistent set-up for the experiment room. There was a chair, a table, a 4 ft2
square tablemat, and all the materials are randomly separated, then placed on the back right corner of
the tablemat.
7-Step sequence
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7-Step Control
7-Step Experimental
10-Step Control
10-Step Experimental
Figure 6: Cheeseburger prototype sequencing procedure
10-Step sequence
Figure 7: Table setting prototype sequencing procedures
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1 Place plate in the center of the mat
2 Place bottom bun on the plate
3 Place burger paddy on top of the bottom bun
4 Place cheese on the burger paddy
5 Place lettuce on top of the cheese
6 Place tomatoes on top of the lettuce
7 Cap off the cheeseburger with the top bun
1 Place large plate in the center of the mat
2 Place small fork to the left of the large plate
3 Place large fork to the left of the small fork
4 Place medium fork to the left of the large fork
5 Place spoon to the right of the large plate
6 Place small plate behind large plate
7 Place knife on the small plate
8 Place cup to the back/right of the large plate
9 Take napkin and fold it once
10 Finish by placing napkin on top of the plate
After the pre-test, the control group explores facebook.com for two minutes while the
experimental group which used our 3D Alice Virtual World demonstration of the 7-step and 10-step
sequences. After two minutes, the participant completes the post-test. Same metrics are recorded for
the post-test as the pre-test, including the time of completion, number of accuracy and sequence
errors).
After the post-test, evaluation forms are filled out by the participant for debriefing and feedback
(see appendix, page xiv).
Statistical Analysis:
We conducted a factorial ANOVA with two between subject factors (2x2 factorial design) using
JMP-8 statistics software. ANOVA is a statistical tool used for continuous data, such as time (measured
in seconds). Post – Pre time represents the improvement (or deterioration). We conducted a chi-
squared contingency test for the accuracy and sequencing errors.
Results and Discussions:
-20
-15
-10
-5
0
Figure 8: Pre- and post average times with error bars
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*Note error bars are of 1 standard deviation.
Significant difference in the sequence improvement was observed between the 7-Step and the
10-Step sequence groups with a p-value of 0.0028 (p<.01). However, no significant difference were
observed in improvement between virtual training versus no virtual training with a p-value of 0.41
(p>>>0.05).
Figure 9: Anova of Post-pre Total Sequence Times
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There is no significant difference between the control and experimental groups for the number
of sequencing errors and number of accuracy errors with a chi square p-value of 0.4843 and 0.1429
respectively. Both errors had p>>0.05.
Figure 10: Chi-squared contingency test for sequencing errors
Figure 11: Chi squared contingency test for number of accurary errors
Informal Observations:
Our design will make rehabilitation more engaging. Patients will want to use our rehabilitation
tool.
Future Work:
The next step of our project is to conduct a clinical study regarding the efficacy of our design
prototype. We already drafted an IRB proposal, as suggested by Dr. Cheng, to prepare for this
procedure. We wish to perform clinical trials using patients with mild traumatic brain injury. The IRB
proposal, once submitted, will take approximately 3 months to get approved.
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We also plan on talking to Dr. David Twillie of Fort Campbell to get more insight on specific tasks
that would help war veterans. We planned a teleconference with him last April 1 , 2010 which he had to
cancel because of unexpected circumstances.
We also plan on creating a prototype that will help patients with navigation skills because this is
one of the needs of war veterans of the Iraq war according to Dr. Drury. This will be similar to a 3D maze
where they have to navigate with a paper map to get to the finish line. The environment will be similar
to the outside environment. We will not use any structures that will remind them of the war because
this will give them flashbacks of the memories that caused them the brain damage.
For our proposed initial design, our inclusion criteria are recent war veterans ages 21-40 with
mild TBI and normal vision.
After having a successful clinical trial, we plan on increasing the difficulty level of the prototype
by adding more steps so that patients can progress to different levels to further their progress.
Conclusion:
In conclusion, our rehabilitation tool showed no significant improvements at sequencing skills
associated with working memory function for healthy college students.
10-step process improved significantly compared to the 7-step process perhaps because of the
room to improve, with extra confusion because of the three extra steps.
No significant improvement from Facebook to virtual rehab tool perhaps because the simplicity
of the sequences. Perhaps both the pretest and post test trials should have been made more difficult,
with greater complexity of sequences. We recommend a long term study which would involve more
repetitions using the virtual rehab tool.
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Economic Issues:
Market Analysis:
More than 1.4 million people are affected in the US annually; 50,000 die; 235,000 are
hospitalized; 1.1 million go through extensive rehabilitation therapy. For children aged less than 15 years
old, TBI results in an estimated 2,685 deaths; 37,000 hospitalizations; 435,000 emergency departments
annually. 5.3 million Americans currently have long-term or lifelong need for help to perform activities
of daily living as a result of TBI. Direct medical costs and indirect costs such as lost productivity totaled
an estimated $60 billion in the year 2000. There is a need for TBI rehabilitation because the lives of TBI
patients are being hindered, both socially and economically.
In addition, companies who hire patients with disabilities get a tax break from the government.
By helping TBI patients be productive, they will be able to gain competence in the job market while
companies will want to hire them due to the generous tax cut.
Competitors:
Most treatment for traumatic brain injury involves rehabilitation centers and hospitals. There
are also some tools and PDAs made to help TBI patients plan their day. No current open source virtual
rehabilitation tool is out on the market.
Patent Search:
We used Google patents and there were no similar patented designs.
Projected Development Cost Analysis:
Materials/Labor Cost Explanation
Alice 3D Software $0 Alice is an open source 3D tool. Anyone can download it
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for free.
Labor $400 1 student @ $10/hr for 40 hours
Hardware equivalent
(Cheeseburger)
$2 Cost of felt ($2). Cost will vary depending on the
number of patients and reusability of materials.
Hardware equivalent (Table
setting)
$2 Cost of plastic spoon ($0.50), plastic fork ($0.50), plastic
knife ($0.50), plastic salad fork ($0.50), paper salad
plate (negligible), paper plate (negligible), cup
(negligible), napkin (negligible). Cost will vary
depending on the number of patients and reusability of
materials.
Instruction manual containing a
consent form, rehabilitation
description, and post evaluation
survey.
$2 Includes paper, printing, binding and data storage.
Total Cost $406
Table 1: Projected Development Cost Analysis Table
*Cost will vary depending on the task assigned. The two tasks listed are the prototype tasks. If a task
includes more steps and involves more delicate materials, cost will be higher. Labor cost is the majority
of the budget for this project. Furthermore, this will vary depending on how quick the student
completes his task.
Benefit Analysis:
This tool, if successful, can potentially help traumatic brain injury patients by lowering
rehabilitation costs not only for war veterans but for patients who generally experience mild TBI. Since
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Alice is an open-source tool, we will be able to provide the service for free or at a low-cost. The protocol
is simple and will not require the presence of trained professionals.
Cost Analysis:
Current rehabilitation treatment for war veterans are free provided by the VA if they are injured
to active duty. However, one study showed that supported employment for helping TBI survivors return
to work costs an average of $10,198 for the 1st year (Wehman, 1994). Our method will be more cost
effective, if successful in improving the patients working memory. Also, there is a social cost associated if
the patient uses datebooks, PDA, special watches or other assisted technologies.
Cost of maintenance:
There is no expected cost of maintenance. The virtual part is open-source and will always be
available for free in the future. The hardware might require maintenance depending on the level of care.
Each hardware prototype is not expensive and can easily be produced for less than $5.
Life Cycle:
Our product is expected to last until a much improved product replaces it.
Marketing Distribution Cost:
First, we will utilize online marketing strategies as most of these are free of cost. We will use
Facebook and Twitter to advertise the product. We will create a website that states the product
description, instructions and objectives. We will also conduct sales talks to cognitive psychology
departments in hospitals in the VA ($30,000/yr). By showing strong statistics on the benefit on using this
tool, rehabilitation centers and patients will adapt this tool.
Risk/Benefit:
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There is no direct associated risk in using this design. There can be positive benefit of the
improvement that might result from this product after successful clinical trials. There is a chance that
method of rehabilitation for TBI patients will be improved.
Human welfare considerations:
Clinical trials will be conducted to patients with traumatic brain injury. On our clinical trials,
patients will be allowed to withdraw anytime during the duration of the study. There is no human risk
associated with the study since they will just watch the interactive video and build the object; however,
possible anxiety and frustration might occur due to excessive mental fatigue and failure. No harmful
materials are involved in the hardware model. The materials used in creating the hardware are made of
felt and plastic.
Ethical/Environmental Considerations:
We will exclude blind participants and people with implicit memory issues. There are no
environmental considerations associated with our design.
Dr. Cheng’s feedback and recommendation:
He helped us get started on our IRB application.
He wished we could have met with Dr. David Twillie from Fort Campbell to know more about
the direct needs of war veterans affected by TBI. We were able to obtain some of the needs by
talking to Dr. Drury.
He believes that it is important to talk to the people you are trying to help. It will help you
understand them more and be able to further improve their quality of life.
Acknowledgement:
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We want to thank Dr. Pamela Drury, neuropsychologist of the VA hospital, for helping us
determine the needs of war veterans with mild traumatic brain injury. We also want to thank Ms.
Christy Hagewood, research nurse of the Vanderbilt Department of Neurosurgery/Spine, for helping us
develop an IRB proposal for a clinical trial of our project.
References:
1. Christiansen C, Abrau B. “Task Performance in Virtual Environments Used for Cognitive Rehabilitation After Traumatic Brain Injury.” Arch Phys Med Rehabil 79(1999)
2. "Facts about Traumatic Brain Injury." Facts About TBI. Web. 8 Nov. 2009. (http://www.brainandspinalcord.org/blog/category/tbi/treatment-tbi/)
3. Finkelstein E, Corso P, Miller T and associates. The Incidence and Economic Burden of Injuries in the United States. New York (NY): Oxford University Press; 2006.
4. Grealy MA, Johnson DA, Rushton SK. "Improving cognitive function after brain injury: the use of exercise and virtual reality." Arch Phys Med Rehabil 80(1999): 661667.
5. Maas AI, Stocchetti N, Bullock R (August 2008). "Moderate and severe traumatic brain injury in adults". Lancet Neurology 7 (8): 728–41.
6. Mangus P and Clemmens D, A tale of two cities, Facets Magazine, vol. Fall/Winter pp.26-27, 2006
7. Myers RL, Laenger CJ. Virtual reality in rehabilitation. Disabil Rehabil. 20(1998): 111-112.8. Okie, M.D., Susan. “Traumatic Brain Injury in War Zone.” Perspective (2005): 2043-2047. June
2009.9. Rao V, Lyketsos C (2000). PTA and LOC stats "Neuropsychiatric Sequelae of Traumatic Brain
Injury". Psychosomatics 41 (2): 95–103.10. Traumatic Brain Injury: The signature wound of the iraq war by the iraq and afghanistan
veterans of american, issue report january 2008.11. Wehman, P., Kregel, J., West, M..& Cifu, D. (1994) Return to Work for Patients with Traumatic
Brain Injury: Analysis of Costs. American Journal of Physical Medicine and Rehabilitation, 73(4): 280-282.
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