TBI Lecture Notes 04.06 and 04.08

Question 1

What is a TBI and how is it caused?

Answer 1

A traumatic brain injury caused by abrupt faces acting on the brain.

Question 2

What are the two categories of TBI?

Answer 2

Penetrating Head Injury (PHI) or Nonpenetrating Head Injury [aka Closed Head injury (aka CHI)]

Question 3

What’s the difference between a CHI and the PHI?

Answer 3

CHI: skull and mengines remain intact
PHI: skull is fractured and meninges are torn

Question 4

What is the biggest cause of TBIs?

Answer 4

Falls comprise 28% of reported cases.

Question 5

Which form of TBI occurs most often?

Answer 5

90% are closed head injuries

Question 6

Greatest risk factor for TBI?

Answer 6

50% admitted to hospitals w/ TBI are intoxicated (e.g., ETOH)

Question 7

Neuropathology of mild/moderate TBI is based on what?

Answer 7

Extrapolation and intuition rather than empirical evidence

Question 8

Adults who survive penetrating head injuries are almost always left with ______, _______, and ________ _______.

Answer 8

physical, cognitive, and linguistic impairments

Question 9

List the two examples of CHI discussed in class

Answer 9

1) Acceleration Injuries (moving-head trauma)

2) Nonacceleration Injuries (fixed-head trauma)

Question 10

Describe a Coup and Countercoup CHI

Answer 10

Aka Linear Acceleration Injuries: Occur when the head is struck by a force aligned with the center axis of the head

Question 11

Describe acceleration Injuries

Answer 11

(moving-head trauma)
Caused by sudden acceleration or deceleration of the head, brain, and brain stem causing diffuse damage due to movement inside skull.

Question 12

Describe Angular Acceleration Injuries

Answer 12

Caused by blows that strike the head off-center, causing it to rotate and move at an angle away from the point of impact

Question 13

Primary consequences of nonacceleration injuries are related to…

Answer 13

deformation of the skull by the impact of the object striking the skull.

Question 14

Blows to a movable head are up to ___ more devastating than blows to a fixed head

Answer 14

20x

Question 15

Injuries to CNI may result in

Answer 15

loss of sense of smell (anosmia)

Question 16

Injuries to CNIII, CNIV, and CNVI may

Answer 16

compromise eye movements, double vision (e.g., diplopia)

Question 17

Injuries to CNIIX may

Answer 17

cause tinnitus or vertigo

Question 18

What is diffuse axonal injury? What is the result?

Answer 18

When acceleration BIs stretch nerve-cell axons throughout the brain and brain stem. Stretched axons swell and separate, and may deteriorate. Assumed to be responsible for many diffuse cognitive and behavioral impairments after such injuries. Severe diffuse axonal injury may lead to vegetative state and is a sign of severe diffuse damage to cortical and subcortical tissues

Question 19

What surfaces are most often damages most in BIs?

Answer 19

As brain moves in the skull during acceleration and deceleration, scrapes along the sharp edges, abrading and lacerating the bottom surfaces of the frontal lobes and anterior temporal lobes

Question 20

What are Epidural hematomas, and how are they caused?

Answer 20

Aka traumatic hemorrhaging. Accumulations of blood between the dura mater and the skull. Caused by skull fractures that lacerate arterial channels in the bone.

Question 21

What is the most common tx for traumatic hemorrhaging?

Answer 21

surgical removal (practical given its location just beneath the skull)

Question 22

What are SDH? Prevalence and gravity relative to epidural hematoma?

Answer 22

Subdural hematoma: accumulation of blood beneath the dura matter. These are twice as common and twice as deadly as epidural hematoma.

Question 23

What population is at greatest risk of SDH?

Answer 23

Old people, and individuals with hx of ETOH.

Question 24

What are Subarachnoid Hematomas?

Answer 24

Rapture of vessels within subarachnoid space. Typical consequence of TBIs, and are usually associated with SDH.

Question 25

What are intracerebral hematomas and what is the cause?

Answer 25

It is a pattern of multiple small intracerebral hemorrhages sometimes occurs in combination w/ diffuse axonal injury caused by translational trauma, often leading to coma and death. Caused by rupture of blood vessels inside the brain (intracerebral hemorrhage).