DoD/VA CODE PROPOSAL FINAL—508 COMPLIANT
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DoD/VA CODE PROPOSAL
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A. DOD/VA COMMON DEFINITION OF TBI
DoD/VA Definition and Symptomatic Taxonomy Working Group and other joint consensus panels developed a definition of traumatic brain injury (TBI) for use in the Departments of Defense (DoD) and Veterans Affairs (VA).
A traumatically induced structural injury and/or physiological disruption of brain function as a result of an external force that is indicated by new onset or worsening of at least one of the following clinical signs, immediately following the event:
□ Any period of loss of or a decreased level of consciousness;
□ Any loss of memory for events immediately before or after the injury;
□ Any alteration in mental state at the time of the injury (confusion, disorientation, slowed thinking, etc.);
□ Neurological deficits (weakness, loss of balance, change in vision, praxis, paresis/plegia, sensory loss, aphasia, etc.) that may or may not be transient;
□ Intracranial lesion
External forces may include any of the following events: the head being struck by an object, the head striking an object, the brain undergoing an acceleration/deceleration movement without direct external trauma to the head, a foreign body penetrating the brain, forces generated from events such as a blast or explosion, or other force yet to be defined.
Not all individuals exposed to an external force will sustain a traumatic brain injury. Traumatic brain injury varies in severity, traditionally described as mild, moderate and severe. These categories are based on measures of length of unconsciousness, post traumatic amnesia.
The trauma may cause structural damage or may produce more subtle damage that manifests by altered brain function, without structural damage that can be detected by traditional imaging studies such as MRI or CT scanning. In addition to traditional imaging studies, other imaging techniques such as fMRI, diffusion tensor imaging, PET scanning, as well as electrophysiological testing such as electroencephalography may be used to detect damage to or physiological alteration of brain function. In addition, altered brain function may be manifest by altered performance on neuropsychological or other standardized testing of function.
Acute injury severity is determined at the time of the injury, but this severity level, while having some prognostic value, does not necessarily reflect the patient's ultimate level of functioning. It is recognized that serial assessments of the patient’s cognitive, emotional, behavioral and social functioning is required.
□ The patient is classified as mild/moderate/severe if he or she meets any of the criteria below within a particular severity level. If a patient meets criteria in more than one category of severity, the higher severity level of severity is assigned.
□ If it is not clinically possible to determine the brain injury level of severity of because of medical complications (e.g. medically induced coma), other severity markers are required to make a determination of the severity of the brain injury.
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It is recognized that the symptoms associated with post traumatic stress disorder (PTSD) may overlap with symptoms of mild traumatic brain injury. Differential diagnosis of brain injury and PTSD is required for accurate diagnosis and treatment.
SEVERITY OF BRAIN INJURY STRATIFICATION
Mild Normal structural imaging LOC = 0-30 min
AOC = a moment up to 24 hrs PTA = 0-1 day GCS=13-15
Moderate
Severe
Normal or abnormal
Normal or abnormal
structural imaging
structural imaging
LOC >30 min and
LOC > 24 hrs
< 24 hours
AOC >24 hours. Severity based on other criteria
PTA >1 and <7 days GCS=9-12
PTA > 7 days GCS=3-8
AOC – Alteration of consciousness/mental state LOC – Loss of consciousness PTA – Post-traumatic amnesia GCS=Glasgow Coma Scale
Note: For purposes of injury stratification, the Glasgow Coma Scale is measured at or after 24 hours
This stratification does not apply to penetrating brain injuries where the dura mater is breached.
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The above criteria define the event of TBI. Sequelae of TBI may resolve quickly, within minutes to hours after the neurological event, or they may persist longer. Some sequelae of TBI may be permanent. Most signs and symptoms will manifest immediately following the event. However, other signs and symptoms may be delayed from days to months (e.g., subdural hematoma, seizures, hydrocephalus, spasticity, etc.). Signs and symptoms may occur alone or in varying combinations and may result in a functional impairment. These signs and symptoms are not better explained by pre-existing conditions or other medical, neurological, or psychological causes except in cases of an exacerbation of a pre-existing condition. These generally fall into one or more of the three following categories:
□ Physical: headache, nausea, vomiting, dizziness, blurred vision, sleep disturbance, weakness, paresis/plegia, sensory loss, spasticity, aphasia, dysphagia, dysarthria, apraxia, balance disorders, disorders of coordination, seizure disorder.
□ Cognitive: attention, concentration, memory, speed of processing, new learning, planning, reasoning, judgment, executive control, self-awareness, language, abstract thinking.
□ Behavioral/emotional: depression, anxiety, agitation, irritability, impulsivity, aggression.
Note: The signs and symptoms listed above are typical of each category but are not an exhaustive list of all possible signs and symptoms.
OTHER DEFINITIONS
There are several common definitions of mild TBI. More severe forms of TBI are defined by imaging, loss of consciousness, altered consciousness, and Glasgow Coma Scare.
National Institutes of Health: Traumatic brain injury, also called acquired brain injury or simply head injury, occurs when a sudden trauma causes damage to the brain. TBI can result when the head suddenly and violently hits an object, or when an object pierces the skull and enters brain tissue. Symptoms of a TBI can be mild, moderate, or severe, depending on the extent of the damage to the brain. A person with a mild TBI may remain conscious or may experience a loss of consciousness for a few seconds or minutes. Other symptoms of mild TBI include headache, confusion, lightheadedness, dizziness, blurred vision or tired eyes, ringing in the ears, bad taste in the mouth, fatigue or lethargy, a change in sleep patterns, behavioral or mood changes, and trouble with memory, concentration, attention, or thinking. A person with a moderate or severe TBI may show these same symptoms, but may also have a headache that gets worse or does not go away, repeated vomiting or nausea, convulsions or seizures, an inability to awaken from sleep, dilation of one or both pupils of the eyes, slurred speech, weakness or numbness in the extremities, loss of coordination, and increased confusion, restlessness, or agitation.
Centers for Disease Control and Prevention: Traumatic brain injury (TBI) is caused by a blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain. Not all blows or jolts to the head result in a TBI. The severity of a TBI may range from “mild,” i.e., a brief change in mental status or consciousness to “severe,” i.e., an extended period of unconsciousness or amnesia after the injury.
• Headaches or neck pain that do not go away; • Difficulty remembering, concentrating, or making decisions; • Slowness in thinking, speaking, acting, or reading;
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• Getting lost or easily confused; • Feeling tired all of the time, having no energy or motivation; • Mood changes (feeling sad or angry for no reason); • Changes in sleep patterns (sleeping a lot more or having a hard time sleeping); • Light-headedness, dizziness, or loss of balance; • Urge to vomit (nausea); • Increased sensitivity to lights, sounds, or distractions; • Blurred vision or eyes that tire easily; • Loss of sense of smell or taste; and • Ringing in the ears.
CDC noted that there was no widely accepted, standard system to classify mild TBI. CDC proposed the following criteria:
Current symptoms reported consequent to mild TBI not present before injury or those made worse in severity or frequency by the mild TBI:
• Problems with memory • Problems with concentration • Problems with emotional control • Headaches • Fatigue • Irritability • Dizziness • Blurred vision • Seizures
Current limitations in functional status reported consequent to MTBI:
• Basic activities of daily living (e.g., personal care, ambulation, travel) • Major activities (e.g., work, school, homemaking) • Leisure and recreation • Social integration • Financial independence
The American Congress of Rehabilitative Medicine (ACRM) defined mild TBI as a traumatically-induced physiological disruption of brain function manifested by at least one of the following:
□ Any period of loss of consciousness
□ Any loss of memory for events immediately before or after the injury
□ Any alteration in mental state at the time of the injury (e.g. feeling dazed, disoriented, or confused).
□ Focal neurological deficit(s) which may or may not be transient; but where the severity of the injury does not exceed the following:
□ Loss of consciousness of approximately 30 minutes or less
□ After 30 minutes, an initial Glasgow Coma Scale of 13-15
□ Post-traumatic amnesia not greater than 24 hours
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Individuals with Disabilities Education Act (IDEA, 34 CFR 300.7) defines TBI as “an acquired injury to the brain caused by an external physical force, resulting in total or partial functional disability or psychosocial impairment, or both, that adversely affects a child’s educational performance. The term applies to open or closed head injuries resulting in impairments in one or more areas, such as cognition, language, perceptual, and motor abilities; psycho-social behavior; physical functions; information processing; and speech. The term does not apply to brain injuries that are congenital or degenerative, or to brain injuries induced by birth trauma.”
Certain aspects of mild TBI are found in Chapter 5 (Mental Disorders). These include cognitive change (310.1), post-concussive syndrome (310.2) and mild memory disturbance (310.8).
There is no single unified definition of mild TBI. Studies have shown that DSM-IV is less inclusive than the ICD-10 criteria because of the cognitive symptoms. The CDC and ACRM definitions are more focused on physiologic brain function or neurological manifestations of TBI than DSM-IV or ICD-10.
DISCUSSION OF BRAIN INJURY STRATIFICATION
There is no standard classification of TBI. While classification systems typically differentiate TBI on the basis of loss of consciousness (LOC), altered consciousness (AOC), posttraumatic amnesia (PTA), or Glasgow Coma Scale (GCS), there is no consensus how these variables define grade of TBI (Table 1).
Table 1. Classification of TBI Severity
Grade
ACRM
VHI
VA/DoD
Mild
LOC ≤ 30 LOC or AOC Normal
min;
< 30 min;
imaging;
Any AOC normal
LOC 0-30
GCS 13- imaging;
min; AOC
15; PTA < GCS=13-15 momentary
24 hours PTA < 24
up to 24
hours
hours; PTA
0-1 day
Moderate
LOC ≤ 6
Normal or
hours;
abnormal
abnormal
imaging;
imaging; GCS LOC > 30
9-12; PTA < 7 min and ≤
days
24 hours;
AOC > 24
hours
(severity
based on
other
factors);
PTA >1 and
<7 days
Severe
LOC > 6
Normal or
hours;
abnormal
abnormal
imaging;
imaging; GCS LOC > 24
< 9; PTA > 7 hours; AOC
days
> 24 hours
(severity
based on
other
factors);
PTA >7
days
Traumatic Brain Injury. Veterans Health Initiative, Employee Education System, Department of Veterans Affairs. DoD/VA
Definition and Symptomatic Taxonomy Working Group Definition.
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Mild TBI (mTBI) or concussion generally involves loss of consciousness last 30 minutes or less, post-traumatic amnesia less than 24 hours, and Glasgow Coma Scale of 13-15. Concussion can be graded according to loss of consciousness and amnesia (Table 2).
Table 2. Classification of Mild TBI (Concussion)
Grade
Cantu
Colorado
AAN
Grade 1
No LOC;
No LOC;
Transient
PTA < 5 min confusion
confusion; no
without
LOC;
amnesia
Concussive
symptoms
resolve < 15
min
Grade 2
LOC < 5 min; No LOC;
Transient
PTA > 30 min confusion
confusion; no
with amnesia LOC;
Concussive
symptoms last
> 15 min
Grade 3
LOC > 5 min; Any LOC
Any LOC
PTA > 24
either brief
hours
(seconds) or
prolonged
(minutes)
Cantu RC. Cerebral concussion in sport. Management and prevention. Sports Med 1992; 14: 64-Report of the Quality
Standards Subcommittee. Practice parameter: the management of concussion in sports (summary statement). Neurology
1997; 48: 581-5. Colorado=Workers Compensation Board, State of Colorado. Traumatic Brain Injury. Veterans Health
Initiative, Employee Education System, Department of Veterans Affairs.
ICD-9-CM CLASSIFICATION OF SEVERITY
ICD-9-CM classifies TBI (concussion) as follows:
850.0 With no loss of consciousness Concussion with mental confusion or disorientation, without loss of consciousness
850.1 With brief loss of consciousness Loss of consciousness for less than one hour
850.11 With loss of consciousness of 30 minutes or less
850.12 With loss of consciousness from 31 to 59 minutes
850.2 With moderate loss of consciousness Loss of consciousness for 1-24 hours
850.3 With prolonged loss of consciousness and return to pre-existing conscious level Loss of consciousness for more than 24 hours with complete recovery
850.4 With prolonged loss of consciousness, without return to pre-existing conscious level
850.5 With loss of consciousness of unspecified duration
850.9 Concussion, unspecified
V15.5 EXTENDERS (DoD)
V15.5_0
OTHER PERSONAL HISTORY PRESENTING HAZARDS TO HEALTH, OTHER
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V15.5_1
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,UNKNOWN LEVEL OF SEVERITY
V15.5_2
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,HIGHEST LEVEL OF SEVERITY MILD (GLASGOW
COMA SCALE 13-15),LOC<1HR,POST TRAUMA AMNESIA<24HR
V15.5_3
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,HIGHEST LEVEL OF SEVERITY MODERATE
(GLASGOW COMA SCALE 9-12),LOC 1-24 HRS,POST TRAUMA AMNESIA 1-6 DAYS
V515.5_4
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,HIGHEST LEVEL OF SEVERITY SEVERE (GLASGOW
COMA SCALE 3-8),LOC >24HRS,POST TRAUMA AMNESIA >6 DAYS
V15.5_5
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,PENETRATING INTRACRANIAL WOUND (NO LEVEL OF
SEVERITY ASSIGNED)
V15.5_6
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI), NOT GWOT
RELATED, UNKNOWN LEVEL OF SEVERITY
V15.5_7
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY MILD
(GLASGOW COMA SCALE 13-15),LOC<1HR,POST TRAUMA AMNESIA<24HR
V15.5_8
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY MODERATE
(GLASGOW COMA SCALE 9-12),LOC 1-24 HRS,POST TRAUMA AMNESIA 1-6 DAYS
V15.5_9
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY SEVERE
(GLASGOW COMA SCALE 3-8),LOC >24HRS,POST TRAUMA AMNESIA >6 DAYS
V15.5_A
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),PENETRATING INTRACRANIAL WOUND (NO
LEVEL OF SEVERITY ASSIGNED)
V15.5_B
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI), UNKNOWN IF
GWOT RELATED, UNKNOWN SEVERITY LEVEL
V15.5_C
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY MILD
(GLASGOW COMA SCALE 13-15),LOC<1HR,POST TRAUMA AMNESIA<24HR
V15.5_D
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY
MODERATE (GLASGOW COMA SCALE 9-12),LOC 1-24 HRS,POST TRAUMA AMNESIA 1-6
DAYS
V15.5_E
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY
SEVERE (GLASGOW COMA SCALE 3-8),LOC >24HRS,POST TRAUMA AMNESIA >6 DAYS
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V15.5_F
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI), UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),PENETRATING INTRACRANIAL
WOUND (NO LEVEL OF SEVERITY ASSIGNED)
DIFFERENCES IN STRATIFICATION SCHEMES
There are differences in stratification of severity in the DoD/VA Common TBI Definition, ICD-9CM, and the V15.5 Extenders (Table 1).
Table 1—Stratification of Severity by Loss of Consciousness
Classification
MILD
MODERATE
DoD/VA Common Definition 0-30 min
>30 min and < 24 hrs
ICD-9-CM
No LOC; brief <1 hr 1 to 24 hrs
(30 min or less, 31
min to 59 min)
V15.5 Extenders
< 1 hr
1 to 24 hrs
SEVERE >24 hrs >24 hrs
>24 hrs
The Common Definition classifies mild TBI as LOC 0 to 30 minutes which is consistent with the American Congress of Rehabilitative Medicine (ACRM) definition. ICD-9-CM and V15.5 Extenders use less than one hour, but ICD-9-CM further differentiates LOC into 30 minutes or less and 31 to 59 minutes. The Common Definition classifies moderate TBI as LOC greater than minutes and less than 24 hours. The other two classification schemes used 1 to 24 hours. All classifications agree on classification of severe TBI as LOC greater than 24 hours. None of the classifications stratify penetrating brain injury as is common practice.
PROPOSAL #1: Revise Intracranial Injury Section
DISCUSSION: Intracranial injuries are broadly classified into two groups: those associated with skull fracture (801-802, 803-804) and those not associated with skull fracture (850 series, 851853 series, and 854 series). See Figure 1. Both categories are stratified by loss of consciousness (LOC). Severity of intracranial injuries associated with skull fracture is indicated by a fifth digit. Intracranial injuries without skull fracture are broadly classified into three groups: (1) concussion (850 series), (2) those associated with specific brain damage such as lacerations, contusions, and hemorrhages (851-853 series), and (3) other and unspecified intracranial injuries (854 series).
Concussion is currently defined and differentiated in the 850 series (concussion). More severe forms of TBI are differentiated from mild TBI (concussion) using codes 850.2 through 850.4. The term “concussion” is a colloquial term; TBI is the preferred term. In contemporary disease classification, mild TBI is synonymous with concussion, but more severe forms of TBI are inappropriately labeled as concussion. Moderate and severe TBI are neither classifiable as concussion nor post-concussive syndrome. Moreover, TBI is differentiated on other factors such as imaging, altered consciousness, and post-traumatic amnesia (see table). The DoD/VA Common TBI Definition classifies mild TBI as loss of consciousness 0-30 minutes and moderate TBI as loss of consciousness as greater than 30 minutes and less than 24 hours. This is consistent with the ACRM Definition.
Intracranial injuries due to specific brain damage include those associated with lacerations and contusions (851) and hemorrhages (852-853). Other and unspecified intracranial injuries are classified in the 854 section.
This proposal revises the 800-series headings to reflect the organization of intracranial injuries and introduces the term “traumatic brain injury” throughout. This proposal also revises the current 850-series concussion codes to reflect current disease classification and revises the index.
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Figure 1. Organization of Intracranial Injuries
Figure 1 shows the organization of intracranial injury codes within ICD-9-CM. Brain and skull injuries are sub-divided into skull fractures without intracranial injury (TBI), intracranial injuries (TBI) with skull fracture, and intracranial injuries (TBI) without skull fracture. The latter subdivision is further sub-divided into three groups: (1) intracranial injuries not associated with specific brain damage (e.g. concussion), (2) intracranial injuries associated with specific brain damage (e.g. contusions, lacerations, or hemorrhages), and (3) other and unspecified intracranial injuries. All groups are stratified by loss of consciousness.
SKULL FRACTURE WITHOUT INTRACRANIAL INJURY (TBI)
NOT ASSOCIATED WITH SPECIFIC BRAIN DAMAGE
• Mild TBI (concussion) • ModerateTBI • Severe TBI • TBI of unspecified
duration Stratified by LOC
BRAIN AND SKULL INJURIES
INTRACRANIAL INJURY (TBI) WITHOUT SKULL FRACTURE
Stratified by LOC
ASSOCIATED WITH SPECIFIC BRAIN DAMAGE
• Contusions • Lacerations • Hemorrhages Stratified by LOC
INTRACRANIAL INJURY (TBI) WITH SKULL FRACTURE
Stratified by LOC
OTHER AND UNSPECIFIED
Stratified by LOC
Proposal #1a: Change section heading to:
INTRACRANIAL INJURY (TRAUMATIC BRAIN INJURY) DUE TO FRACTURE OF SKULL (800-804)
Fifth digit subclassification for 800-801, 803-804 codes):
0 unspecified state of consciousness 1 with no loss of consciousness 2 with brief [less than one hour] loss of consciousness 3 with moderate [1-24 hours] loss consciousness 4 with prolonged [more than 24 hours] loss of consciousness and return to pre-existing
conscious level 5 with prolonged [more than 24 hours] loss of consciousness, without return to pre-existing
conscious level 6 with loss of consciousness of unspecified duration 9 with concussion or TBI, unspecified
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Proposal #1b: Change indexing as follows:
Injury, brain (traumatic brain injury) 850-854 See also Injury, intracranial
Injury, intracranial (traumatic brain injury) 850-854
With no loss of consciousness 850.0 Mild TBI 850.11 Moderate TBI (loss of consciousness 31-59 minutes) 850.12 Moderate TBI (loss of consciousness, 1-24 hours) 850.2 Severe TBI (loss of consciousness more than 24 hours) with return to preexisting level 850.3 Severe TBI (loss of consciousness more than 24 hours) without return to preexisting level 850.4 With unspecified duration 850.5 TBI, unspecified 850.9
Proposal #1c: Change section heading to:
INTRACRANIAL INJURY (TRAUMATIC BRAIN INJURY), EXCLUSING THOSE WITH SKULL FRACTURE (850-854)
Fifth digit subclassification for 851-854 codes):
0 unspecified state of consciousness 1 with no loss of consciousness 2 with brief [less than one hour] loss of consciousness 3 with moderate [1-24 hours] loss consciousness 4 with prolonged [more than 24 hours] loss of consciousness and return to pre-existing
conscious level 5 with prolonged [more than 24 hours] loss of consciousness, without return to pre-existing
conscious level 6 with loss of consciousness of unspecified duration 9 with concussion or TBI, unspecified
PROPOSAL #1d: Differentiate TBI under 850
850 Intracranial Injury (Traumatic Brain Injury) Not Associated with Specific Brain Injury
850.0
With no loss of consciousness Concussion or mild traumatic brain injury with mental confusion or disorientation, without loss of consciousness
850.1 With brief loss of consciousness Loss of consciousness for less than one hour
850.11 With loss of consciousness of 30 minutes or less Mild traumatic brain injury with loss of consciousness of 30 minutes or less
850.12 With loss of consciousness from 31 to 59 minutes
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A. DOD/VA COMMON DEFINITION OF TBI
DoD/VA Definition and Symptomatic Taxonomy Working Group and other joint consensus panels developed a definition of traumatic brain injury (TBI) for use in the Departments of Defense (DoD) and Veterans Affairs (VA).
A traumatically induced structural injury and/or physiological disruption of brain function as a result of an external force that is indicated by new onset or worsening of at least one of the following clinical signs, immediately following the event:
□ Any period of loss of or a decreased level of consciousness;
□ Any loss of memory for events immediately before or after the injury;
□ Any alteration in mental state at the time of the injury (confusion, disorientation, slowed thinking, etc.);
□ Neurological deficits (weakness, loss of balance, change in vision, praxis, paresis/plegia, sensory loss, aphasia, etc.) that may or may not be transient;
□ Intracranial lesion
External forces may include any of the following events: the head being struck by an object, the head striking an object, the brain undergoing an acceleration/deceleration movement without direct external trauma to the head, a foreign body penetrating the brain, forces generated from events such as a blast or explosion, or other force yet to be defined.
Not all individuals exposed to an external force will sustain a traumatic brain injury. Traumatic brain injury varies in severity, traditionally described as mild, moderate and severe. These categories are based on measures of length of unconsciousness, post traumatic amnesia.
The trauma may cause structural damage or may produce more subtle damage that manifests by altered brain function, without structural damage that can be detected by traditional imaging studies such as MRI or CT scanning. In addition to traditional imaging studies, other imaging techniques such as fMRI, diffusion tensor imaging, PET scanning, as well as electrophysiological testing such as electroencephalography may be used to detect damage to or physiological alteration of brain function. In addition, altered brain function may be manifest by altered performance on neuropsychological or other standardized testing of function.
Acute injury severity is determined at the time of the injury, but this severity level, while having some prognostic value, does not necessarily reflect the patient's ultimate level of functioning. It is recognized that serial assessments of the patient’s cognitive, emotional, behavioral and social functioning is required.
□ The patient is classified as mild/moderate/severe if he or she meets any of the criteria below within a particular severity level. If a patient meets criteria in more than one category of severity, the higher severity level of severity is assigned.
□ If it is not clinically possible to determine the brain injury level of severity of because of medical complications (e.g. medically induced coma), other severity markers are required to make a determination of the severity of the brain injury.
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It is recognized that the symptoms associated with post traumatic stress disorder (PTSD) may overlap with symptoms of mild traumatic brain injury. Differential diagnosis of brain injury and PTSD is required for accurate diagnosis and treatment.
SEVERITY OF BRAIN INJURY STRATIFICATION
Mild Normal structural imaging LOC = 0-30 min
AOC = a moment up to 24 hrs PTA = 0-1 day GCS=13-15
Moderate
Severe
Normal or abnormal
Normal or abnormal
structural imaging
structural imaging
LOC >30 min and
LOC > 24 hrs
< 24 hours
AOC >24 hours. Severity based on other criteria
PTA >1 and <7 days GCS=9-12
PTA > 7 days GCS=3-8
AOC – Alteration of consciousness/mental state LOC – Loss of consciousness PTA – Post-traumatic amnesia GCS=Glasgow Coma Scale
Note: For purposes of injury stratification, the Glasgow Coma Scale is measured at or after 24 hours
This stratification does not apply to penetrating brain injuries where the dura mater is breached.
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The above criteria define the event of TBI. Sequelae of TBI may resolve quickly, within minutes to hours after the neurological event, or they may persist longer. Some sequelae of TBI may be permanent. Most signs and symptoms will manifest immediately following the event. However, other signs and symptoms may be delayed from days to months (e.g., subdural hematoma, seizures, hydrocephalus, spasticity, etc.). Signs and symptoms may occur alone or in varying combinations and may result in a functional impairment. These signs and symptoms are not better explained by pre-existing conditions or other medical, neurological, or psychological causes except in cases of an exacerbation of a pre-existing condition. These generally fall into one or more of the three following categories:
□ Physical: headache, nausea, vomiting, dizziness, blurred vision, sleep disturbance, weakness, paresis/plegia, sensory loss, spasticity, aphasia, dysphagia, dysarthria, apraxia, balance disorders, disorders of coordination, seizure disorder.
□ Cognitive: attention, concentration, memory, speed of processing, new learning, planning, reasoning, judgment, executive control, self-awareness, language, abstract thinking.
□ Behavioral/emotional: depression, anxiety, agitation, irritability, impulsivity, aggression.
Note: The signs and symptoms listed above are typical of each category but are not an exhaustive list of all possible signs and symptoms.
OTHER DEFINITIONS
There are several common definitions of mild TBI. More severe forms of TBI are defined by imaging, loss of consciousness, altered consciousness, and Glasgow Coma Scare.
National Institutes of Health: Traumatic brain injury, also called acquired brain injury or simply head injury, occurs when a sudden trauma causes damage to the brain. TBI can result when the head suddenly and violently hits an object, or when an object pierces the skull and enters brain tissue. Symptoms of a TBI can be mild, moderate, or severe, depending on the extent of the damage to the brain. A person with a mild TBI may remain conscious or may experience a loss of consciousness for a few seconds or minutes. Other symptoms of mild TBI include headache, confusion, lightheadedness, dizziness, blurred vision or tired eyes, ringing in the ears, bad taste in the mouth, fatigue or lethargy, a change in sleep patterns, behavioral or mood changes, and trouble with memory, concentration, attention, or thinking. A person with a moderate or severe TBI may show these same symptoms, but may also have a headache that gets worse or does not go away, repeated vomiting or nausea, convulsions or seizures, an inability to awaken from sleep, dilation of one or both pupils of the eyes, slurred speech, weakness or numbness in the extremities, loss of coordination, and increased confusion, restlessness, or agitation.
Centers for Disease Control and Prevention: Traumatic brain injury (TBI) is caused by a blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain. Not all blows or jolts to the head result in a TBI. The severity of a TBI may range from “mild,” i.e., a brief change in mental status or consciousness to “severe,” i.e., an extended period of unconsciousness or amnesia after the injury.
• Headaches or neck pain that do not go away; • Difficulty remembering, concentrating, or making decisions; • Slowness in thinking, speaking, acting, or reading;
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• Getting lost or easily confused; • Feeling tired all of the time, having no energy or motivation; • Mood changes (feeling sad or angry for no reason); • Changes in sleep patterns (sleeping a lot more or having a hard time sleeping); • Light-headedness, dizziness, or loss of balance; • Urge to vomit (nausea); • Increased sensitivity to lights, sounds, or distractions; • Blurred vision or eyes that tire easily; • Loss of sense of smell or taste; and • Ringing in the ears.
CDC noted that there was no widely accepted, standard system to classify mild TBI. CDC proposed the following criteria:
Current symptoms reported consequent to mild TBI not present before injury or those made worse in severity or frequency by the mild TBI:
• Problems with memory • Problems with concentration • Problems with emotional control • Headaches • Fatigue • Irritability • Dizziness • Blurred vision • Seizures
Current limitations in functional status reported consequent to MTBI:
• Basic activities of daily living (e.g., personal care, ambulation, travel) • Major activities (e.g., work, school, homemaking) • Leisure and recreation • Social integration • Financial independence
The American Congress of Rehabilitative Medicine (ACRM) defined mild TBI as a traumatically-induced physiological disruption of brain function manifested by at least one of the following:
□ Any period of loss of consciousness
□ Any loss of memory for events immediately before or after the injury
□ Any alteration in mental state at the time of the injury (e.g. feeling dazed, disoriented, or confused).
□ Focal neurological deficit(s) which may or may not be transient; but where the severity of the injury does not exceed the following:
□ Loss of consciousness of approximately 30 minutes or less
□ After 30 minutes, an initial Glasgow Coma Scale of 13-15
□ Post-traumatic amnesia not greater than 24 hours
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Individuals with Disabilities Education Act (IDEA, 34 CFR 300.7) defines TBI as “an acquired injury to the brain caused by an external physical force, resulting in total or partial functional disability or psychosocial impairment, or both, that adversely affects a child’s educational performance. The term applies to open or closed head injuries resulting in impairments in one or more areas, such as cognition, language, perceptual, and motor abilities; psycho-social behavior; physical functions; information processing; and speech. The term does not apply to brain injuries that are congenital or degenerative, or to brain injuries induced by birth trauma.”
Certain aspects of mild TBI are found in Chapter 5 (Mental Disorders). These include cognitive change (310.1), post-concussive syndrome (310.2) and mild memory disturbance (310.8).
There is no single unified definition of mild TBI. Studies have shown that DSM-IV is less inclusive than the ICD-10 criteria because of the cognitive symptoms. The CDC and ACRM definitions are more focused on physiologic brain function or neurological manifestations of TBI than DSM-IV or ICD-10.
DISCUSSION OF BRAIN INJURY STRATIFICATION
There is no standard classification of TBI. While classification systems typically differentiate TBI on the basis of loss of consciousness (LOC), altered consciousness (AOC), posttraumatic amnesia (PTA), or Glasgow Coma Scale (GCS), there is no consensus how these variables define grade of TBI (Table 1).
Table 1. Classification of TBI Severity
Grade
ACRM
VHI
VA/DoD
Mild
LOC ≤ 30 LOC or AOC Normal
min;
< 30 min;
imaging;
Any AOC normal
LOC 0-30
GCS 13- imaging;
min; AOC
15; PTA < GCS=13-15 momentary
24 hours PTA < 24
up to 24
hours
hours; PTA
0-1 day
Moderate
LOC ≤ 6
Normal or
hours;
abnormal
abnormal
imaging;
imaging; GCS LOC > 30
9-12; PTA < 7 min and ≤
days
24 hours;
AOC > 24
hours
(severity
based on
other
factors);
PTA >1 and
<7 days
Severe
LOC > 6
Normal or
hours;
abnormal
abnormal
imaging;
imaging; GCS LOC > 24
< 9; PTA > 7 hours; AOC
days
> 24 hours
(severity
based on
other
factors);
PTA >7
days
Traumatic Brain Injury. Veterans Health Initiative, Employee Education System, Department of Veterans Affairs. DoD/VA
Definition and Symptomatic Taxonomy Working Group Definition.
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Mild TBI (mTBI) or concussion generally involves loss of consciousness last 30 minutes or less, post-traumatic amnesia less than 24 hours, and Glasgow Coma Scale of 13-15. Concussion can be graded according to loss of consciousness and amnesia (Table 2).
Table 2. Classification of Mild TBI (Concussion)
Grade
Cantu
Colorado
AAN
Grade 1
No LOC;
No LOC;
Transient
PTA < 5 min confusion
confusion; no
without
LOC;
amnesia
Concussive
symptoms
resolve < 15
min
Grade 2
LOC < 5 min; No LOC;
Transient
PTA > 30 min confusion
confusion; no
with amnesia LOC;
Concussive
symptoms last
> 15 min
Grade 3
LOC > 5 min; Any LOC
Any LOC
PTA > 24
either brief
hours
(seconds) or
prolonged
(minutes)
Cantu RC. Cerebral concussion in sport. Management and prevention. Sports Med 1992; 14: 64-Report of the Quality
Standards Subcommittee. Practice parameter: the management of concussion in sports (summary statement). Neurology
1997; 48: 581-5. Colorado=Workers Compensation Board, State of Colorado. Traumatic Brain Injury. Veterans Health
Initiative, Employee Education System, Department of Veterans Affairs.
ICD-9-CM CLASSIFICATION OF SEVERITY
ICD-9-CM classifies TBI (concussion) as follows:
850.0 With no loss of consciousness Concussion with mental confusion or disorientation, without loss of consciousness
850.1 With brief loss of consciousness Loss of consciousness for less than one hour
850.11 With loss of consciousness of 30 minutes or less
850.12 With loss of consciousness from 31 to 59 minutes
850.2 With moderate loss of consciousness Loss of consciousness for 1-24 hours
850.3 With prolonged loss of consciousness and return to pre-existing conscious level Loss of consciousness for more than 24 hours with complete recovery
850.4 With prolonged loss of consciousness, without return to pre-existing conscious level
850.5 With loss of consciousness of unspecified duration
850.9 Concussion, unspecified
V15.5 EXTENDERS (DoD)
V15.5_0
OTHER PERSONAL HISTORY PRESENTING HAZARDS TO HEALTH, OTHER
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V15.5_1
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,UNKNOWN LEVEL OF SEVERITY
V15.5_2
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,HIGHEST LEVEL OF SEVERITY MILD (GLASGOW
COMA SCALE 13-15),LOC<1HR,POST TRAUMA AMNESIA<24HR
V15.5_3
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,HIGHEST LEVEL OF SEVERITY MODERATE
(GLASGOW COMA SCALE 9-12),LOC 1-24 HRS,POST TRAUMA AMNESIA 1-6 DAYS
V515.5_4
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,HIGHEST LEVEL OF SEVERITY SEVERE (GLASGOW
COMA SCALE 3-8),LOC >24HRS,POST TRAUMA AMNESIA >6 DAYS
V15.5_5
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),GLOBAL WAR
ON TERRORISM (GWOT) RELATED,PENETRATING INTRACRANIAL WOUND (NO LEVEL OF
SEVERITY ASSIGNED)
V15.5_6
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI), NOT GWOT
RELATED, UNKNOWN LEVEL OF SEVERITY
V15.5_7
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY MILD
(GLASGOW COMA SCALE 13-15),LOC<1HR,POST TRAUMA AMNESIA<24HR
V15.5_8
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY MODERATE
(GLASGOW COMA SCALE 9-12),LOC 1-24 HRS,POST TRAUMA AMNESIA 1-6 DAYS
V15.5_9
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY SEVERE
(GLASGOW COMA SCALE 3-8),LOC >24HRS,POST TRAUMA AMNESIA >6 DAYS
V15.5_A
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),NOT RELATED
TO GLOBAL WAR ON TERRORISM (GWOT),PENETRATING INTRACRANIAL WOUND (NO
LEVEL OF SEVERITY ASSIGNED)
V15.5_B
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI), UNKNOWN IF
GWOT RELATED, UNKNOWN SEVERITY LEVEL
V15.5_C
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY MILD
(GLASGOW COMA SCALE 13-15),LOC<1HR,POST TRAUMA AMNESIA<24HR
V15.5_D
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY
MODERATE (GLASGOW COMA SCALE 9-12),LOC 1-24 HRS,POST TRAUMA AMNESIA 1-6
DAYS
V15.5_E
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI),UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),HIGHEST LEVEL OF SEVERITY
SEVERE (GLASGOW COMA SCALE 3-8),LOC >24HRS,POST TRAUMA AMNESIA >6 DAYS
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V15.5_F
PERSONAL HISTORY OF TRAUMATIC BRAIN INJURY (TBI), UNKNOWN IF
RELATED TO GLOBAL WAR ON TERRORISM (GWOT),PENETRATING INTRACRANIAL
WOUND (NO LEVEL OF SEVERITY ASSIGNED)
DIFFERENCES IN STRATIFICATION SCHEMES
There are differences in stratification of severity in the DoD/VA Common TBI Definition, ICD-9CM, and the V15.5 Extenders (Table 1).
Table 1—Stratification of Severity by Loss of Consciousness
Classification
MILD
MODERATE
DoD/VA Common Definition 0-30 min
>30 min and < 24 hrs
ICD-9-CM
No LOC; brief <1 hr 1 to 24 hrs
(30 min or less, 31
min to 59 min)
V15.5 Extenders
< 1 hr
1 to 24 hrs
SEVERE >24 hrs >24 hrs
>24 hrs
The Common Definition classifies mild TBI as LOC 0 to 30 minutes which is consistent with the American Congress of Rehabilitative Medicine (ACRM) definition. ICD-9-CM and V15.5 Extenders use less than one hour, but ICD-9-CM further differentiates LOC into 30 minutes or less and 31 to 59 minutes. The Common Definition classifies moderate TBI as LOC greater than minutes and less than 24 hours. The other two classification schemes used 1 to 24 hours. All classifications agree on classification of severe TBI as LOC greater than 24 hours. None of the classifications stratify penetrating brain injury as is common practice.
PROPOSAL #1: Revise Intracranial Injury Section
DISCUSSION: Intracranial injuries are broadly classified into two groups: those associated with skull fracture (801-802, 803-804) and those not associated with skull fracture (850 series, 851853 series, and 854 series). See Figure 1. Both categories are stratified by loss of consciousness (LOC). Severity of intracranial injuries associated with skull fracture is indicated by a fifth digit. Intracranial injuries without skull fracture are broadly classified into three groups: (1) concussion (850 series), (2) those associated with specific brain damage such as lacerations, contusions, and hemorrhages (851-853 series), and (3) other and unspecified intracranial injuries (854 series).
Concussion is currently defined and differentiated in the 850 series (concussion). More severe forms of TBI are differentiated from mild TBI (concussion) using codes 850.2 through 850.4. The term “concussion” is a colloquial term; TBI is the preferred term. In contemporary disease classification, mild TBI is synonymous with concussion, but more severe forms of TBI are inappropriately labeled as concussion. Moderate and severe TBI are neither classifiable as concussion nor post-concussive syndrome. Moreover, TBI is differentiated on other factors such as imaging, altered consciousness, and post-traumatic amnesia (see table). The DoD/VA Common TBI Definition classifies mild TBI as loss of consciousness 0-30 minutes and moderate TBI as loss of consciousness as greater than 30 minutes and less than 24 hours. This is consistent with the ACRM Definition.
Intracranial injuries due to specific brain damage include those associated with lacerations and contusions (851) and hemorrhages (852-853). Other and unspecified intracranial injuries are classified in the 854 section.
This proposal revises the 800-series headings to reflect the organization of intracranial injuries and introduces the term “traumatic brain injury” throughout. This proposal also revises the current 850-series concussion codes to reflect current disease classification and revises the index.
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Figure 1. Organization of Intracranial Injuries
Figure 1 shows the organization of intracranial injury codes within ICD-9-CM. Brain and skull injuries are sub-divided into skull fractures without intracranial injury (TBI), intracranial injuries (TBI) with skull fracture, and intracranial injuries (TBI) without skull fracture. The latter subdivision is further sub-divided into three groups: (1) intracranial injuries not associated with specific brain damage (e.g. concussion), (2) intracranial injuries associated with specific brain damage (e.g. contusions, lacerations, or hemorrhages), and (3) other and unspecified intracranial injuries. All groups are stratified by loss of consciousness.
SKULL FRACTURE WITHOUT INTRACRANIAL INJURY (TBI)
NOT ASSOCIATED WITH SPECIFIC BRAIN DAMAGE
• Mild TBI (concussion) • ModerateTBI • Severe TBI • TBI of unspecified
duration Stratified by LOC
BRAIN AND SKULL INJURIES
INTRACRANIAL INJURY (TBI) WITHOUT SKULL FRACTURE
Stratified by LOC
ASSOCIATED WITH SPECIFIC BRAIN DAMAGE
• Contusions • Lacerations • Hemorrhages Stratified by LOC
INTRACRANIAL INJURY (TBI) WITH SKULL FRACTURE
Stratified by LOC
OTHER AND UNSPECIFIED
Stratified by LOC
Proposal #1a: Change section heading to:
INTRACRANIAL INJURY (TRAUMATIC BRAIN INJURY) DUE TO FRACTURE OF SKULL (800-804)
Fifth digit subclassification for 800-801, 803-804 codes):
0 unspecified state of consciousness 1 with no loss of consciousness 2 with brief [less than one hour] loss of consciousness 3 with moderate [1-24 hours] loss consciousness 4 with prolonged [more than 24 hours] loss of consciousness and return to pre-existing
conscious level 5 with prolonged [more than 24 hours] loss of consciousness, without return to pre-existing
conscious level 6 with loss of consciousness of unspecified duration 9 with concussion or TBI, unspecified
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Proposal #1b: Change indexing as follows:
Injury, brain (traumatic brain injury) 850-854 See also Injury, intracranial
Injury, intracranial (traumatic brain injury) 850-854
With no loss of consciousness 850.0 Mild TBI 850.11 Moderate TBI (loss of consciousness 31-59 minutes) 850.12 Moderate TBI (loss of consciousness, 1-24 hours) 850.2 Severe TBI (loss of consciousness more than 24 hours) with return to preexisting level 850.3 Severe TBI (loss of consciousness more than 24 hours) without return to preexisting level 850.4 With unspecified duration 850.5 TBI, unspecified 850.9
Proposal #1c: Change section heading to:
INTRACRANIAL INJURY (TRAUMATIC BRAIN INJURY), EXCLUSING THOSE WITH SKULL FRACTURE (850-854)
Fifth digit subclassification for 851-854 codes):
0 unspecified state of consciousness 1 with no loss of consciousness 2 with brief [less than one hour] loss of consciousness 3 with moderate [1-24 hours] loss consciousness 4 with prolonged [more than 24 hours] loss of consciousness and return to pre-existing
conscious level 5 with prolonged [more than 24 hours] loss of consciousness, without return to pre-existing
conscious level 6 with loss of consciousness of unspecified duration 9 with concussion or TBI, unspecified
PROPOSAL #1d: Differentiate TBI under 850
850 Intracranial Injury (Traumatic Brain Injury) Not Associated with Specific Brain Injury
850.0
With no loss of consciousness Concussion or mild traumatic brain injury with mental confusion or disorientation, without loss of consciousness
850.1 With brief loss of consciousness Loss of consciousness for less than one hour
850.11 With loss of consciousness of 30 minutes or less Mild traumatic brain injury with loss of consciousness of 30 minutes or less
850.12 With loss of consciousness from 31 to 59 minutes
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