Minor Brain Trauma:
Pathology, Imaging,
and Clinical Aspects
Donald W Chakeres MD, FACR
Professor of Radiology
Department of Radiology
The Ohio State University
Columbus, Ohio, USA
XIX Symposium Neuroradiologicum, Bologna, Italy 2010
Seongjin Choi, PhD
Postdoctoral Fellow
Department of Radiology
Dustin Cunningham
Student Research Assistant
Department of Radiology
John D. Corrigan, PhD
Professor
Department of Phys. Med. and Rehab.
Department of Psychology
Devin F. Prior
Student Research Assistant
Department of Radiology
Jennifer A. Bogner, PhD
Associate Professor
Department of Phys. Med. and Rehab.
W Jerry Mysiw, MD
Professor and Vice Chair
Department of Phys. Med. and Rehab.
Department of Psychology
S. Sammet MD, PhD
Assistant Professor
Department of Radiology
Cherian R Zachariah, BS
Graduate Research Associate
Department of Radiology
Michael V. Knopp, MD, PhD
Professor and Vice Chair
Department of Radiology
Petra Schmalbrock, PhD
Associate Professor
Department of Radiology
 Preview
of the presentation
 Define minor head trauma
 Clinical findings/ spectrum
 Pathology, animal and human
 Imaging findings, focusing on 7 T
MRI
 Conclusions
If you are looking for great imaging findings
that will impact your routine practice, you
are going to be disappointed
 Minor head trauma by definition usually
does not have routine imaging findings
 Still a very important topic since it is a
common indication for imaging
 Advanced imaging does have the
potential to become the biomarker
measure






Head trauma is extremely common
Minor head trauma is commonly followed
by repeated or major head trauma
In America there are over 5 million with long
term disability as a result of head trauma
The incidence of minor head trauma is
essentially everyone
It is a very serious problem dwarfing many
other medical issues
There is no known effective therapy
 Most therapy is just to wait and see if the
symptoms improve, frequently they do
 The treatment for stress and trauma are
frequently identical
 If you cannot measure the injury directly
you cannot measure if your therapy is
effective either

The classification is not well defined for
imaging or clinical measures
 Glasgow Coma Scale, not good for
minor head injuries, better for serious
injuries

Grade 1: transient confusion with no
loss of consciousness, and symptoms
resolve in less than 15 minutes
 Grade 2: symptoms last for more than 15
minutes
 Grade 3: loss of consciousness


Normal routine CT and MRI
Loss of consciousness
 Head ache
 Confusion
 Dizzy
 Inability to concentrate
 Does not recall the event
 Change in personality
 Executive function impairment

Post traumatic stress syndrome
 Depression
 Drug dependence
 Workman’s compensation incentives


Major brain injuries much better understood because
of excellent pathologic material

Disruption without physical shearing of the
neurofilaments
Animal studies show “ball” like swelling of axons
suggesting separation, but without gross visible focal
parenchymal injury, analogous to MS and normal
appearing white matter
Stretching and tearing of neurons occur at the instant
of trauma


Povlishock JT, Becker DP, et al, Axonal change in minor head Injury, Journal of Neuropathology and Experimental Neurology
Wide spread damage to the white
matter need not be associated with
hemorrhage, contusion, or laceration
 This is why advanced imaging may be
very important

Nevin, Norman, Neuropahtological changes in white matter following head trauma,
Journal of Neuropathology and Experimental Neurology 1967
Kors E, et al, Delayed cerebral edema and fatal coma after minor head trauma: role of the CACNA1A calcium channel
subunit gene and relationship with familial hemiplegic migraine, Ann Neurol 2001:49:753-760





Loss of consciousness may the clinical
marker of the “tearing” of the neurons
The brainstem foci may well account for
loss of consciousness
Location can be “anywhere”, but classic
anatomic distribution
Animal studies show injuries to the inferior
colliculus, pons and dorsolateral medulla
Axonal injury is highly under estimated
Jane J, et al, Axonal degeneration induced by experimental noninvasive minor head injury
Gentleman, SM, Roberts GW, et al , Axonal injury: a universal consequence of
Fatal closed head injury, Acta Neuropathol 1995:89:537-543
Midbrain lesions found in 23 of 35
autopsied, head injury subjects
 Abnormal evoked potential before
death
 Midbrain damage almost always
associated with major hemispheric injury

Rosenblum, W, et al, Midbrain lesion: frequent and significant prognostic feature in closed head injury
Neurosurgery, Congress of Neurologic Surgeons
ApoE is a genetic marker that is
associated with Alzheimer’s disease
 An error in “healing” the brain after injury
 The risk of significant post traumatic
disability is increased for subjects with the
same ApoE genes as patients at risk for
Alzheimer’s disease
 Beta-amyloid deposits are found with the
apolipoprotineE (apoE)-ε4 allele.

β‐Amyloid (Aβ)42(43), Aβ42, Aβ40 and apoE immunostaining of plaques in fatal head injury
K. Horsburgh, G. M. Cole, F. Yang, M. J. Savage B. D. Greenberg, S. M. Gentleman, D. I. Grahamand J. A. R. Nicoll
Association of apolipoprotein E polymophism with outcome after head injury,
The Lancet volume 350, issue 9084, 1069-1071
90% improve with no therapy
 Can occur without any head motion,
classic acceleration- deceleration
 The blast waves can go through the
thinner bone skull regions such as the
orbit and still lead to distortion/ injury of
the brain
 Usually more than one blast needed
before any clinical symptoms

Subdural hematoma
 Epidural hematoma
 Subarachnoid hemorrhage
 Brain contusions
 Diffuse axonal injuries
 Brain lacerations
 Depressed skull fracture
 Vessel disruption, spasm, dissection,
aneurym

Technique developed by Haacke/ et al
 More commonly available now, and
standard on some systems
 Uses a image processed combination of
phase and magnitude data
 Very sensitive to deoxyhemoglobin since
it has strong paramagnetic properties
that accelerate the local phase
 Good for the veins and hemorrhage

Much better than simple gradient echo
imaging for subtle blood products
 Patients with “normal CT and MRI” may
have many lesions by SWI
 Seen as low “signal” regions in typical
locations for shear injuries and trauma

T2
FLAIR
T2
SWI
Diffusion imaging should be a good
technique for a subtle injury since it is
sensitive to the integrity of the axons
 FA and ADC values may be abnormal
with brain injury
 Diffusion tensor/ tract imaging, DTT,
should even be more sensitive

Data comparable to 3 T data, but higher
resolution
 Fractional anisotropy, FA, values lower in
corpus callosum, CC, compared to controls
 Healthy normal subjects showed changes
of FA with age, FA decreases with
increasing age
 Tractography of CC showed fewer and less
well defined tracts in the trauma group

Normal control
Post Traumatic Subject
Dustin T. Cunningham, Seongjin Choi, John D. Corrigan, Jennifer Bogner,
W. Jerry Mysiw, Cherian R. Zachariah, Michael V. Knopp and
Petra Schmalbrock
The Ohio State University
Department of Radiology
Wright Center of Innovation in Biomedical Imaging
Methods
Subjects
 7 chronic mild TBI with normal conventional MRI (ages 2260)
 (Glasgow Coma Scale GCS 13-15)
 10 approx. age matched healthy (22-56)
Imaging
 7T (Philips, Achieva)
 16-channel receive (Nova Medical)
 SS-SE-EPI DTI, TR/TE = 5126/75 ms
 voxel: 1.6×1.6×3.2 mm3
 b = 0, 1000 s/mm2
 6 b-directions, 3 high b averages
 SENSE-factor = 5
 DTI scan time: 2min, 24sec
 3D SWI, voxel: .40×.68×1.6 mm3
 flip angle = 5, scan time: 5min, 4sec
Cingulum Bundles
7T Identification
Philips FiberTrak
Wakana et al. NeuroImage 2007
CB Tractography Scoring
3
2
1
DTI Studio – H. Jiang and S. Mori, Johns Hopkins University
CB Tractography Scoring
Control
TBI
Mean Scores
Mean Scores
3
3
2
2
1
1
0
0
Left Control
Left TBI
Right
Control
Observer 1
Right TBI
Left Control
Left TBI
Right
Control
Observer 2
Right TBI
Summary

Visual tractography differences can be
detected in chronic mild TBI compared with
controls with 7T

Quantitative FA values were lower in
chronic mild TBI than controls

Despite B0 and B1 inhomogeneity, 7T DTI
consistent with 3T and 1.5T studies of mild
TBI





Inglese M, Makani S, Johnson G, Cohen BA, Silver JA, Gonen O, and
Grossman RI, Diffuse Axonal Injury in Mild Traumatic Brain Injury: A
Diffusion Tensor Imaging Study, Journal of Neurosurgery 103:298-303,
2005
Kraus MF, Susmaras T, Caughlin BP, Walker CJ, Sweeney JA, and
Little DM, White Matter Integrity and Cognition in Chronic Traumatic
Brain Injury: A Diffusion Tensor Imaging Study, Brain 130:2508-2519,
2007
Kumar R, Husain M, Gupta RK, Hasan KM, Haris M, Agarwal AK,
Pandey CM, and Narayana PA, Serial Changes in the White Matter
Diffusion Tensor Imaging Metrics in Moderate Traumatic Brain Injury
and Correlation with Neuro-Cognitive Function, Journal of
Neurotrauma 26:481-495, April 2009
Li TQ, van Gelderen P, Merkle H, Talagala L, Koretsky AP, Duyn J,
Extensive heterogeneity in white matter intensity in high-resolution
T2*-weighted MRI of the human brain at 7T, NeuroImage 32, 10321040, 2006
Sugiyama K, Kondo T, Higano S, Endo M, Watanabe H, Shindo K,
Izumi SI, Diffusion tensor imaging fiber tractography for evaluating
diffuse axonal injury, Brain Injury, 21: 413-419, 2007






“Minor” head trauma is a major medical
issue
Pathology has shown many important
findings not commonly identified otherwise
Some patients are at a genetic risk
MR imaging may be the future of an
accurate biomarker for brain injury
“Normal” imaging may not be normal
Advanced techniques are much more
sensitive for imaging findings of TBI