The single most important
thing that will determine how
much damage Rep. Gabrielle
Giffords (D-Ariz.) suffered in
Saturday's shooting is the
precise path the bullet took
through her brain - a detail
not yet revealed by her
physicians.
A general description of the
wound and Giffords's condition
suggests the bullet may have
missed the language and
vision regions of her brain. But
it may have damaged a region
responsible for controlling
parts of the right side of her
body, as well as areas
involved in understanding
sensations and planning
movements.
Her long-term outcome,
however, also depends on
numerous other variables,
some of which will be known
soon and others not for
months. They include whether
the brain swells further and
complications such as wound
infection or pneumonia can be
avoided, as well as the skill
and duration of rehabilitative
therapy and how hard the
patient works at it.
"It's speculative and difficult
to predict what will happen,"
said Michael R. Yochelson,
medical director for brain
injury programs at National
Rehabilitation Hospital, in
Washington. "More than in
any other field of medicine
the response to this kind of
injury is so individualized."
Nevertheless, the brain is the
most precisely organized
organ in the body. Regions are
responsible for specific
actions, often very different
ones even when the regions
are near each other. The left
side of the brain, where
Giffords is injured, functions
somewhat differently from the
right. Bullets whose
trajectories differ by a few
degrees of an angle or are
fractions of an inch apart can
have profoundly different
consequences.
As a result of this functional
topography, it's possible to
describe the general sort of
disability that might result
from a wound.
A back-to-front bullet track,
as Giffords's appears to be,
would have more devastating
consequences the closer it is
to the neck. A path near the
top of the head would cause
both less and different
damage. Giffords's wound
appears to be more like the
latter than the former.
The evidence for that is her
ability to respond to the
spoken request to display a
certain number of fingers.
Many parts of the brain are
involved in that task, but
language comprehension
resides mostly in what's
known as Wernicke's area,
which is part of the temporal
lobe near the temple and ear.
The bullet appears to have
passed above that area. It
may have entered high
enough to also miss the visual
cortex, which ends about
halfway up the back of the
head. Asked whether
Giffords's vision was impaired,
her neurosurgeon at
University Medical Center in
Tucson, Michael Lemole, said
it hadn't been tested but "the
hope is that it won't be
affected."
A trajectory going back to
front at that level on the left
side of the head would pass
through through the parietal
and frontal lobes, large
regions involved in
complicated mental actions.
The bullet would hit the left
visual association area at the
back of the head first. That
region is responsible for
determining the meaning of
what one sees. Damage can
result in "neglect syndromes,"
in which a person is unaware
of objects on one side. The
person may fail to eat food on
the right side of a plate, and
in severe cases may not even
recognize a right arm or leg
as his or her own.
That region is also involved in
comprehension of symbols,
such as the numbers and
hands on a clock. A person
also may not be able to put in
correct order a series of
pictures, such as ones showing
a full plate of cookies, a boy
next to a half-empty plate and
an empty plate.
Farther forward, the bullet
would hit the somatic sensory
cortex, which is responsible
for comprehending touch. A
person with damage there
may not be able to identify
that a quarter placed in the
hand is a coin.
Forward of that is the motor
cortex, which contains brain
cells that control specific
muscles. Which parts of the
body - toes, leg, arm, finger,
face - may be permanently
weakened or paralyzed
depends on exactly where the
bullet passes. The left side of
the brain controls the right
side of the body, so any
disability would be on the
right.
Forward of that are areas
responsible for planning
complex movements, such as
walking, and for controlling
eye movements. Closest to the
forehead is a section of the
brain responsible for mood,
self-control and creative
thought.
Giffords is on a ventillator and
sedated most of the time to
minimize stress to her brain.
The extent of her disabilities
isn't known. But the fact she
can follow directions is
extremely encouraging,
several experts said.
"Her prognosis for maintaining
the function that she has is
very good. It's over 50
percent," said Army Col.
Geoffrey Ling, a neurological
intensive-care physician at the
Uniformed Services University
in Bethesda who flew to
Tucson on Monday to consult
on the case.
Source:http://www.washingtonpost.com/wp-dyn/content/article/2011/01/10/AR2011011006771.html
thing that will determine how
much damage Rep. Gabrielle
Giffords (D-Ariz.) suffered in
Saturday's shooting is the
precise path the bullet took
through her brain - a detail
not yet revealed by her
physicians.
A general description of the
wound and Giffords's condition
suggests the bullet may have
missed the language and
vision regions of her brain. But
it may have damaged a region
responsible for controlling
parts of the right side of her
body, as well as areas
involved in understanding
sensations and planning
movements.
Her long-term outcome,
however, also depends on
numerous other variables,
some of which will be known
soon and others not for
months. They include whether
the brain swells further and
complications such as wound
infection or pneumonia can be
avoided, as well as the skill
and duration of rehabilitative
therapy and how hard the
patient works at it.
"It's speculative and difficult
to predict what will happen,"
said Michael R. Yochelson,
medical director for brain
injury programs at National
Rehabilitation Hospital, in
Washington. "More than in
any other field of medicine
the response to this kind of
injury is so individualized."
Nevertheless, the brain is the
most precisely organized
organ in the body. Regions are
responsible for specific
actions, often very different
ones even when the regions
are near each other. The left
side of the brain, where
Giffords is injured, functions
somewhat differently from the
right. Bullets whose
trajectories differ by a few
degrees of an angle or are
fractions of an inch apart can
have profoundly different
consequences.
As a result of this functional
topography, it's possible to
describe the general sort of
disability that might result
from a wound.
A back-to-front bullet track,
as Giffords's appears to be,
would have more devastating
consequences the closer it is
to the neck. A path near the
top of the head would cause
both less and different
damage. Giffords's wound
appears to be more like the
latter than the former.
The evidence for that is her
ability to respond to the
spoken request to display a
certain number of fingers.
Many parts of the brain are
involved in that task, but
language comprehension
resides mostly in what's
known as Wernicke's area,
which is part of the temporal
lobe near the temple and ear.
The bullet appears to have
passed above that area. It
may have entered high
enough to also miss the visual
cortex, which ends about
halfway up the back of the
head. Asked whether
Giffords's vision was impaired,
her neurosurgeon at
University Medical Center in
Tucson, Michael Lemole, said
it hadn't been tested but "the
hope is that it won't be
affected."
A trajectory going back to
front at that level on the left
side of the head would pass
through through the parietal
and frontal lobes, large
regions involved in
complicated mental actions.
The bullet would hit the left
visual association area at the
back of the head first. That
region is responsible for
determining the meaning of
what one sees. Damage can
result in "neglect syndromes,"
in which a person is unaware
of objects on one side. The
person may fail to eat food on
the right side of a plate, and
in severe cases may not even
recognize a right arm or leg
as his or her own.
That region is also involved in
comprehension of symbols,
such as the numbers and
hands on a clock. A person
also may not be able to put in
correct order a series of
pictures, such as ones showing
a full plate of cookies, a boy
next to a half-empty plate and
an empty plate.
Farther forward, the bullet
would hit the somatic sensory
cortex, which is responsible
for comprehending touch. A
person with damage there
may not be able to identify
that a quarter placed in the
hand is a coin.
Forward of that is the motor
cortex, which contains brain
cells that control specific
muscles. Which parts of the
body - toes, leg, arm, finger,
face - may be permanently
weakened or paralyzed
depends on exactly where the
bullet passes. The left side of
the brain controls the right
side of the body, so any
disability would be on the
right.
Forward of that are areas
responsible for planning
complex movements, such as
walking, and for controlling
eye movements. Closest to the
forehead is a section of the
brain responsible for mood,
self-control and creative
thought.
Giffords is on a ventillator and
sedated most of the time to
minimize stress to her brain.
The extent of her disabilities
isn't known. But the fact she
can follow directions is
extremely encouraging,
several experts said.
"Her prognosis for maintaining
the function that she has is
very good. It's over 50
percent," said Army Col.
Geoffrey Ling, a neurological
intensive-care physician at the
Uniformed Services University
in Bethesda who flew to
Tucson on Monday to consult
on the case.
Source:http://www.washingtonpost.com/wp-dyn/content/article/2011/01/10/AR2011011006771.html
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