Monday, January 10, 2011

NPR - How Neurosurgeons Size Up Brain Injuries Like Giffords'

Dr. Peter Rhee, right, speaks about the condition of U.S. Rep. Gabrielle Giffords, D-Ariz., as Dr. G. Michael Lemole, Jr., looks on at University Medical Center during a news conference in Tucson, Ariz., Sunday, Jan. 9, 2011.
Dr. Peter Rhee, right, speaks about the condition of U.S. Rep. Gabrielle Giffords, D-Ariz., as Dr. G. Michael Lemole, Jr., looks on at University Medical Center. Tucson, Ariz., Sunday, Jan. 9, 2011.

I just listened to this segment on NPR as I drove home from a massage - most people die from the wound Gabriel Giffords suffered, so in that respect she is somewhat lucky. And the bullet may not have hit the most sensitive language centers, but it did traverse the higher regions of the left hemisphere, impacting movement among many other functions.

[At the bottom of the page are some more scientific explanations of Giffords' injuries and the efforts to save her life - remarkable efforts.]

One thing that has not been mentioned, as far as I have heard, is that the bullet took out part of the frontal lobe, parietal lobe, temporal lobe, and prefrontal cortex - areas involved in higher functions such as executive function, planning, and self regulation.

The following are some of the major brain areas likely to be damaged by the bullet - each of these lobes has several smaller regions with more specific functions, as is seen with the prefrontal cortex being a more specialized (and crucial) part of the frontal lobe.

Front lobe:
The frontal lobes are considered our emotional control center and home to our personality. There is no other part of the brain where lesions can cause such a wide variety of symptoms (Kolb & Wishaw, 1990). The frontal lobes are involved in motor function, problem solving, spontaneity, memory, language, initiation, judgement, impulse control, and social and sexual behavior. The frontal lobes are extremely vulnerable to injury due to their location at the front of the cranium, proximity to the sphenoid wing and their large size. MRI studies have shown that the frontal area is the most common region of injury following mild to moderate traumatic brain injury (Levin et al., 1987).
Parietal lobe:

The parietal lobes can be divided into two functional regions. One involves sensation and perception and the other is concerned with integrating sensory input, primarily with the visual system. The first function integrates sensory information to form a single perception (cognition). The second function constructs a spatial coordinate system to represent the world around us. Individuals with damage to the parietal lobes often show striking deficits, such as abnormalities in body image and spatial relations (Kandel, Schwartz & Jessel, 1991).

Damage to the left parietal lobe can result in what is called "Gerstmann's Syndrome." It includes right-left confusion, difficulty with writing (agraphia) and difficulty with mathematics (acalculia). It can also produce disorders of language (aphasia) and the inability to perceive objects normally (agnosia).

Temporal lobe:

Kolb & Wishaw (1990) have identified eight principle symptoms of temporal lobe damage: 1) disturbance of auditory sensation and perception, 2) disturbance of selective attention of auditory and visual input, 3) disorders of visual perception, 4) impaired organization and categorization of verbal material, 5) disturbance of language comprehension, 6) impaired long-term memory, 7) altered personality and affective behavior, 8) altered sexual behavior.

Selective attention to visual or auditory input is common with damage to the temporal lobes (Milner, 1968). Left side lesions result in decreased recall of verbal and visual content, including speech perception. Right side lesions result in decreased recognition of tonal sequences and many musical abilities. Right side lesions can also effect recognition of visual content (e.g. recall of faces).

The temporal lobes are involved in the primary organization of sensory input (Read, 1981). Individuals with temporal lobes lesions have difficulty placing words or pictures into categories.

Language can be effected by temporal lobe damage. Left temporal lesions disturb recognition of words. Right temporal damage can cause a loss of inhibition of talking.

The temporal lobes are highly associated with memory skills. Left temporal lesions result in impaired memory for verbal material. Right side lesions result in recall of non-verbal material, such as music and drawings.

Prefrontal cortex:

The prefrontal cortex (PFC) is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.

This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior.[1] The basic activity of this brain region is considered to be orchestration of thoughts and actions in accordance with internal goals.[2]

The most typical psychological term for functions carried out by the prefrontal cortex area is executive function. Executive function relates to abilities to differentiate among conflicting thoughts, determine good and bad, better and best, same and different, future consequences of current activities, working toward a defined goal, prediction of outcomes, expectation based on actions, and social "control" (the ability to suppress urges that, if not suppressed, could lead to socially-unacceptable outcomes).

Many authors have indicated an integral link between a person's personality and the functions of the prefrontal cortex.[3]

Anyway, I have nothing but hope for Giffords and her family that she heals quickly and fully, but I would not be (am not) too optimistic that she ever will be the same person she was before this violent attack.
by Jon Hamilton and Scott Hensley

With Rep. Gabrielle Giffords hospitalized in Tucson, Ariz., after Saturday's shooting, we checked in with some leading neurosurgeons for insights into her condition and what the future might hold.

You'll be able to listen to Jon Hamilton's report on Monday's All Things Considered and Tuesday's Morning Edition. Here are excerpts, edited for length and clarity, from interviews done for the pieces.

Dr. Keith Black
Cedars Sinai

Dr. Keith Black

Dr. Keith Black, chairman of neurosurgery at Cedars Sinai Medical Center, Los Angeles.

Q: The trajectory of the bullet through Giffords' brain appears to have been higher than initially thought. Why would that be a good sign?

A: The language areas are lower down. There's one in the left temporal lobe, which is responsible for comprehension of language, and there's another area in the lower frontal lobe, off to the side, that's critical for expression of language. If the bullet is high, then it can avoid those two areas. The one caveat with the bullet being higher is that the motor areas can be high, particularly the motor areas that control the legs.

Q: What should we watch for in the next few days?

A: The maximum amount of swelling typically occurs three days after injury. Tomorrow (Tuesday) is going to be an important day to make sure she doesn't get into any increased swelling issues or any pressure issues. After that things should start to stabilize and improve. If she hasn't had any new bleeding by this time that's also a very positive sign. The next big step for her is going to be getting off the respirator. When they wake her up and see if she can support her respirations.

Q: Have you treated patients who have an injury like this and seen them walk out eventually in pretty good shape?

A: Absolutely. The fact she got immediate care, got to the CT scanner, and got neurosurgical attention right away is very positive.

Dr. Henry Brem
Johns Hopkins

Dr. Henry Brem

Dr. Henry Brem, chief of neurosurgery at Johns Hopkins Hospital, Baltimore.

Q: What can you say about the course of care for patients with injuries like Giffords'?

A: When someone comes in and they're alert and following commands, there's the hope they survive the injury and get through successfully. The fact that the person is awake and alert coming into the emergency room is a very good prognostic sign.

Q: What's the most important factor?

A: It's all about what damage was done. Clearly what you hope for is that the bullet is as superficial as possible. The bottom line is the functions. If someone is able to talk or follow verbal commands then that means you have understood spoken language, processed it and turned it into a function — into doing something to follow that command. That, in and of itself, tests a great deal of the brain.

Q: What lies ahead for Giffords?

It's a terrible injury to have. But, given that, the longer that she's alive and the longer she has encouraging signs, the more encouraging it is for the future. The best predictor for how she's going to do is how these next few days unfold.

Dr. Jonathan Jagid
Univ. of Miami

Dr. Jonathan Jagid

Dr. Jonathan Jagid, assistant professor of neurological surgery, Miller School of Medicine, University of Miami.

Q: What sorts of things are doctors treating Giffords looking for?

A: Whenever you've got an injury to the brain or any part of the body it swells. The difference between your arm swelling and the brain is that the brain is in a closed compartment. Once the damage has been done from the bullet, the only thing you're trying to prevent from there on out is what's called secondary injury from swelling of the brain.

More on this tragedy (in terms of the brain science):

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