Prediction of Outcome after Acute Brain Injury

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Prediction of Outcome after Acute Brain Injury

• Jamie Sleigh
• Intensive Care Unit
• Waikato Hospital

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Outline/Themes

• Why bother? prediction and explanation
• 3 Dimensions of damage
• Psycho-social
• Neurological / functional
• Structural / anatomical
• Modes of imaging
• clinical, electrophysiological, anatomical,
  other/CBF etc...
• Spectrum of injury - mild to severe/dead
• Primary vs secondary injury

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What is the psycho-social outcome post-ICU head
injury?

• 123 adults with severe brain trauma - ICU.
• gt1SD mild, gt2SD severe.
• Evaluated 1yr post injury
• WAIS-R / D-span / symbol(attention/IQ)
• 35-60 severe
• AVLT(verbal memory) 54 severe
• COWA(executive function) 38 severe

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Clinical Prediction of Outcome?! (WAIS-R) vs
Post resuscitation level-of-consciousness (GCS)
WAIS-R
GCS
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The Spatial Imaging Smorgasbord

• Computed Tomography (CT),
• Magnetic resonance imaging (MRI),
• (fMRI)
• Single-Photon Emission Computed Tomography
  (SPECT).
• Positron Emission Tomography (PET)

Blood flow... Anatomical
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The Functional Imaging Smorgasbord

• EEG
• Evoked Potentials
• Brain Stem Auditory Evoked Potentials
• Midlatency Auditory Evoked Potentials
• Visual EP
• Event related potentials
• Somato-sensory evoked potentials

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(Functional) Outcome Prediction from (Anatomical)
CT is weakFrontal Lobe CT damage vs Functional
outcome (COWA)
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Functional Outcome vs ICU Rx, and Somatosensory
Evoked Potentials (24-48hrs post injury)
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Predictive value of somatosensory evoked
potentials for awakening from coma. Crit Care
Med. 2003 Mar31(3)960-7.
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PET
Significant correlation between cognitive and
behavioral disorders and decreased cortical
metabolism in the prefrontal and cingulate
cortex in patients with severe traumatic brain
injury Fontaine A, Azouvi P, Remy P, et al
Functional anatomy of neuropsychological
deficits after severe traumatic brain injury.
Neurology 53(9)1963-1968, 1999Rao N, Turski PA,
Polcyn RE, et al 18F positron emission computed
tomography in closed head injury. Arch Phys Med
Rehab 65780-785, 1984Ruff RM, Buchsbaum SM,
Troster AI, et al Computed tomography,
neuropsychology, and positron emission
tomography in the evaluation of head injury.
Neuropsych Neuropsychol Behav Neurol 2103-123,
1989
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SPECT CBF

• Abnormal CT - 55.
• Abnormal SPECT - 80
• 39 SPECT ve, CT -ve
• 27 CT ve, SPECT -ve
• For prognosis SPECT gt CT Bavetta S, Nimmon CC,
  McCabe J, et al A prospective study comparing
  SPET with MRI and CT as prognostic indicators
  following severe closed head injury. Nucl Med
  Comm 15961-968, 1994
• Mild head injury normal CT Abdel-Dayem HM,
  Abu-Judeh H, Kumar M, et al SPECT brain
  perfusion abnormalities in mild or moderate
  traumatic brain injury. Clin Nucl Med 23309-317,
  1998
• 68 had an abnormal SPECT study.
• Focal areas of hypoperfusion were seengt75
  patients

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SPECT, vs MRI, vs Clinical state

• Kesler et al, Brain Injury 200014851.
• n 52, 4/12 to 5yrs post injury
• SPECT vs MRI
• 67 agreement
• MR vs verbal memory, r -0.24
• Neuropsychological Impairment Rating vs MRI, r
  0.23

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SPECT vs Behavioural and Neuropsychological
measures

• Severe TBI.
• Decreased blood flow to the frontal lobes ?
  disinhibitive behavior.
• Decreased blood flow in the left cerebral
  hemisphere ? Social Isolation.
• ? SPECT findings may help determine the
  behavioral and psychosocial sequelae of head
  trauma
• Oder W, Goldenberg G, Spatt J. et al Behavioral
  and psychosocial sequelae of severe closed head
  injury and regional cerebral blood flow. A SPECT
  study. J Neurol Neurosurg Psych 55475-480, 1992

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Mild Traumatic Brain Injury / Post-Concussion
Syndrome LOClt30min, amnesia lt24hr, GCSgt12, ...

• Who goes on to PCS?
• Malingering / Litigation??
• MRI
• Evoked Potentials
• S-100B

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Event related potentials vs Post-concussion
symptoms
18-34yrs

• Gaetz - Brain Injury 200014815
• BAEP, MLAEP, Visual P100, Auditory P3(00),
  CNV(auditory and visual)
• Visual ERP p300
• 8/20 gt2.5SD in patients with persistent
  concussion.

35-55yrs
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A troponin of the brain?Post-concussion S-100B

• Herrman et al. J Neurol Neurosurg Psychiatry
  20017095
• n69, mild TBI patients
• Elevated S-100B (and neuron-specific enolase) gt
  Neuropsychological impairment (at 6/12)
• Leon Macdonald !!!!!
• CT no use

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S-100B may not correlate with MRI

• Aktar, Ped Crit Care Med 20034322.
• N 17,
• Mild TBI in paediatrics
• 7 pts MRI positive
• No difference in S-100B

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Conclusions

• Anatomical imaging (CT) is for discrete lesions
  not functional recovery.
• Role of SPECT is unclear.
• MRI, ERPs, and ?S-100B are predictive of MBI/Post
  concussion syndrome.
• Correlation is not prediction