Traumatic Brain Injury: Overview & Perspectives. September 27, 2013 Louis T. Giron, Jr., M.D Neurology Section VAMC Kansas City, Missouri

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1 Traumatic Brain Injury: Overview & Perspectives September 27, 2013 Louis T. Giron, Jr., M.D Neurology Section VAMC Kansas City, Missouri

2 Johnny, I hardly knew ye. Popular English song, 19 th Century

3 Definition of TBI (CDC, 1995) Head injury with one of the following: Decrease in level of consciousness Amnesia Skull fracture Objective neurologic or neuropsychological abnormalities Diagnosed intracranial lesions

4 Definition (exclusions) For this presentation, we will exclude 1) those acute conditions requiring emergent neurosurgical intervention such as intracerebral hemorrhage, skull fracture & penetrating brain injury 2) acute (transient) postconcussive syndrome

5 Are we having fun yet?

6 Epidemiology Combat About 23 % (immediate report) in combat brigade or 7.5% reported after deployment IED (blast injury) Other Civilian 519/100,000 (US Census, 1996) or about 1.3 million (TBI) injuries per year MVA Occupational Sports Alcohol Elderly (falls) Assaults 6

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8 IED Explosion

9 Shell shock Term from WWI, somewhat controversial even during WWI, considered to be more psychological than neurological Now recognized as a consequence of blast injury (highly energetic pressure waves transmitted through atmosphere) Sometime used to indicate PTSD

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11 Epidemiology/ Consequences Functionally impairs (long-term disability) from 3.2 to 5.2 million or 1-2% of the population of the US. A silent epidemic of immense consequences economically and in terms of human suffering.

12 Epidemiology Male predominance, favored by psychiatric & cognitive disturbance Higher in US than in Europe Chief cause of death in individuals ages 1 to 45 75% treated in ER only 19% hospitalized 3% fatal

13 GLASCOW COMA SCALE

14 Military head trauma differs from civilian counterpart More likely from repeated concussions Polytrauma more likely (amputations, etc.) Visual, hearing and vestibular dysfunction common Blast injury more often the cause Penetrating injuries more likely but like civilian counterpart tends to be under reported

15 Severity of TBI Mild GCS Moderate GCS 9-12 Severe GCS 8 or less Other indications of severity Duration of LOC Duration of post-traumatic amnesia

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17 Head Strap

18 Epidemiology Mild TBI Sports Under-reporting common (43% with concussion knowingly hid symptoms) Football High School: 20% College: 10% NFL veterans: 35%

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20 Double Impact Syndrome Rare neurologic syndrome from 2nd injury occuring in a vulnerable period following an initial injury resulting in deficits (including death) far in excess of those expected from apparent simple additive effects

21 Prevention of Sports Concussion Conditioning and training Helmets (protective gear) Rules favoring safe conduct Enforcement of rules clean play e.g., ban spear tackling. Educate athletes, parents and coaches

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23 Management of Sports Concussion Rest the mind (avoid computer use, texting, returning to school or other activities too quickly). The pain in brain is mainly in the strain. Ask responsible adult to observe Do not take medications without doctor s permission Eat nutritious foods, drink plenty of water Rest the body (at least 7-8 hours of sleep/night)

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25 Return to Play Step-wise No RTP in current game Physician evaluation following injury Rule out more serious injury & prevent complications cognitive rest Gradual return to school & work Gradual return to sports competition (when school performance returns to base-line) Legislation in many states requires these or similar precautions. Kansas requires physician OK for return to play.

26 On-line aid/apps Heads Up/app Concussion/app

27 Coup & Countre-coup

28 Gross neuropathology

29 Conventional/Ideal Neuroimaging CT head: identifies lesions demanding acute neurosurgical intervention MRI: may identify region responsible for focal deficits or seizures Ideal MRI : should identify those patients with mild TBI who will be more likely to have persistent cognitive/behavioral

30 Diffuse Axonal Injury Diffusion Sequence MRI

31 Mechanisms of Injury (Direct and Immediate) Shearing: diffuse axonal injury, usually at the grey-white matter junction Focal contusions: hemorrhages, coupcountre-coup Extra-axial (outside substance of brain); e.g., subdural and extradural hematomas,

32 Principles Each TBI case is unique The exact physical conditions can never be duplicated Each individual differs biologically; e.g., previous injury, biological reserve, etc. The consequence is that the clinical picture varies enormously

33 Symptoms of TBI Psychological/Psychiatric Depression Guilt Anxiety PTSD?? Amotivation Neurologic Cognitive: memory, executive function Headache Vertigo Sensory impairment Seizures Parkinsonism Neuroendocrine Sleep disturbances

34 Cognitive Symptoms of Mild TBI Immediately Slowed reaction time Headache Inattention Dizziness Typically resolve after 1-3 months

35 Chronic Traumatic Encephalopathy Made headlines when NFL veterans have been diagnosed with condition Controversial how distinct a syndrome Dementia pugilistica or punch drunk Insidious, progressive Associated with cerebral atrophy, esp medial temporal lobe, thalamus, brainstem. A possible contributing factor to Alzheimer s disease 35

36 Fractional Anisotropy in Mild TBI

37 Relation to PTSD Complex & poorly understood Damage to prefrontal cortex may disrupt neural pathways that regulate anxiety. Post-concussive symptoms may increase likelihood of PTSD

38 Relation to PTSD (2) Controversial as prolonged unconsciousness had been tied to lower chance to acquire PTSD However, in soldiers with TBI with LOC, the incidence of PTSD was slightly more than 27%

39 Relation to PTSD (3) Cognitive or neurobehavioral changes from TBI may interfere with the efficacy of ungoing psychotherapy

40 The polytrauma triad Blast-related co-morbidities Chronic pain 82% PTSD 68% Persistent postconcussive symptoms 67% About 42% will have all 3 conditions concurently

41 Prediction on return to work in civilian practice Minimal extracerebral injuries Low level of pain

42 Factors Contributing to Functional Impairment Extracranial injuries Amputation of limb. Hemorrhagic shock Hypoxemia Sensory impairment PTSD

43 Sleep Disturbances in TBI (1) About 46% of chronic TBI will have sleep disorders, but they are often unrecognized May result from hypothalamic dysregulation Hypersomnia: OSA, narcolepsy, PLMS Insomnia: sleep maintenance as well as sleep onset insomnia Parasomnias: REM behavior most common

44 Sleep Disturbances in TBI (2) Circadian rhythm sleep disorders: delayed sleep phase syndrome & irregular sleepwake patterns Conventional therapies appear effective Therefore, these conditions ought to be recognized since they can contribute significantly to neurocognitive deficits and functional impairment

45 Other Diagnostic Methods Now, almost-now & future MRI with Diffusion Tensor Imaging Voxel based morphometry MRI-SPECT fused imaging NMR spectroscopy Correlation of neuropsychological impairment to specific regions Quantitative electroencephalography

46 Fractional Anisotropy in TBI a: tracts are displayed b: chaos normal noise/physical disruption TBI

47 Current Treatment Multi-disciplinary Treat pain Treat contributory &/or co-morbid conditions Prevent future injury (traumatic or otherwise) Cognitive rehabilitation Appropriate psychoactive agents Vocational training

48 What does the future hold? Prevention: e.g., world peace, better helmets, etc. Early identification of those more severely affected, the ideal MRI, functional test, etc. NMDA antagonists: amantadine, memantine Identification and treatment of genetic risk factors for progressive encephalopathy Improved auto safety, traffic control & sport rules Change in awareness of consequences of even mild TBI

49 Future Combat Helmet with input from Tom Clancy

50 Summary: TBI Silent epidemic, affecting large numbers Often overlooked, under-reported & underestimated in significance Variable in severity, but often catastrophic Controversial if causative but adversely interacts with PTSD High economic & human cost May be responsible for and in turn worsened by sleep disorders Treatment & management are in infancy