Neuroscience Week 6: CNS Trauma

Question 1

Traumatic parenchymal injuries

3 listed

Answer 1

• Concussion
• Contusion
• Diffuse axonal injury

Question 3

Concussion description

Answer 3

Transient neurologic dysfunction (with or without loss of consciousness, transient respiratory arrest, loss of reflexes)

Question 4

Repeated concussions can result in?

Answer 4

Repeated episodes can result in chronic traumatic encephalopathy (with cognitive impairment, Parkinsonism)

Question 5

Contusion description

Answer 5

caused by rapid tissue displacement, disruption of vasculature, with subsequent hemorrhage, tissue injury and edema. Coup and contrecoup are the most common types.

Question 6

Contusion types

2 listed

Answer 6

• Coups
• Contrecoup

Question 7

Coup contusion

Answer 7

contusion that occurs at the point of impact

Question 8

Contrecoup contusion

Answer 8

contusion that occurs opposite the point of impact

Question 9

Contusion common location

Answer 9

involving the crest of the gyri in regions overlying rough and irregular inner skull surfaces (e.g. orbitofrontal and temporal lope tips)

Question 10

Identify

Answer 10

Question 11

Contusions histology

Answer 11

• perivascular petechial hemorrhages with red neuron cell changes
• Neutrophils infiltrate within 2 hours
• Macrophages infiltrate at approximately 48 hours

Question 12

Diffuse axonal injury: adults common causes

Answer 12

due to high velocity accidents (motor vehicle collisions, falling from a building)

Question 13

Diffuse axonal injury: Infants common causes

Answer 13

Can be due to homicidal head injuries (so-called shaken baby syndrome)

Question 14

Diffuse axonal injury trauma type

Answer 14

Due to rotational acceleration deceleration injuries

Question 15

Diffuse axonal injury location

Answer 15

Affects the white matter tracts of the brain and brainstem (corpus callosum, internal capsule, parasagittal white matter, cerebral peduncles of the mid brain, cervico medullary junction, etc)

Question 16

Diffuse axonal injury histology

Answer 16

• axonal spheroids
• Amyloid precursor protein immunostain demonstrating axonal spheroids

Question 17

Diffuse axonal injury symptoms

Answer 17

Immediate loss of consciousness

Question 18

Diffuse axonal injury overview

Answer 18

Question 19

Epidural hematoma common causes

Answer 19

Accidental falls are the leading cause > traffic accidents > assaults

Question 20

Epidural hematoma etiology

Answer 20

• Result from laceration of the dural arteries (classically the middle meningeal artery) with rapid accumulation of blood in minutes-to-hours
• There is usually an associated temporal skull fracture

Question 21

Epidural hematoma Treatment

Answer 21

Epidural hematomas are neurosurgical emergencies and if not evacuated may lead to herniation and death

Question 22

Epidural hematoma lucid interval

Answer 22

There is a ‘lucid’ interval in 1/3 of the cases (“talk and die”; more common in pediatric population)

Question 23

Epidural hematoma trauma type

Answer 23

Epidural hematomas are more commonly associated with impact rather than acceleration-deceleration type incidents

Question 24

Epidural hematoma overview

Answer 24

Question 25

Subdural Hematoma origin

Answer 25

have venous origin resulting in slower accumulation of blood (hours-to-days, to even weeks)

Question 26

Subdural Hematoma Etiology & risk

Answer 26

* result from rupture of bridging (between dural sinuses and cortical vessels) veins in the subdural space * more common in patietns with reduced brain volume (elderly, alcohol use disorder) or infants (who have thin-walled bridging veins)

Question 27

Subdural Hematoma Trauma type

Answer 27

* common with acceleration-deceleration type incidents * Manifest within 48 hrs of injury with headache, confusion and progressive neurological deterioration

Question 28

Subdural Hematoma size of hemorrhage

Answer 28

* These hemorrhages range in size from just a film of blood to large life-threatening masses * May be bilateral

Question 29

Chronic Subdural Hematoma

Answer 29

As the hemorrhages resolve they become organized by granulation tissue and fibrosis, forming a cavity which may re-bleed, resulting in a chronic subdural hematoma

Question 30

Subdural Hematoma Prognosis

Answer 30

* Most subdural hemorrhages, however, resolve to a thin, hemosiderin-stained fibrous membrane as the blood products are resorbed * Accumulation may be delayed

Question 31

Subdural Hematoma Overview

Answer 31

Question 32

Traumatic vascular injury

Answer 32

* Epidural hematoma * subdural hematoma

Question 33

Herniations

Answer 33

Question 34

Herniation syndromes

Answer 34

Question 35

Subfalcine herniation

Answer 35

* when the cingulate gyrus herniates underneath the dural falx, which can compromise ACA blood flow * This represents a space-occupying lesion on the right hemisphere (for example, right sided subdural hematoma)

Question 36

Tentorial (Uncal) Herniation description

Answer 36

* involves the medial aspect of the temporal lobe herniating across the tentorium cerebelli * may damage ipsilateral oculomotor nerve * may occlude the posterior cerebral artery

Question 37

Tentorial (Uncal) Herniation Clinical presentation

Answer 37

* Dilated pupil * down and out pupil * weakness on the contralateral side

Question 38

Tentorial (Uncal) Herniation Massive herniation

Answer 38

* a Massive herniation may push the contralateral cerebral peduncle against the tentorium cerebelli (Kernohan's notch) * resulting in ipsilateral weakness

Question 39

Duret Hemorrhage

Answer 39

* Caudal displacement and elongation of brainstem congestion and rupture of the paramedian pontine branches of the basilar artery or penetrating veins and arteries supplying the midbrain * Causes linear or flameshaped hemorrhages in midbrain and pons

Question 40

Tonsilar herniation description

Answer 40

* occludes the foramen magnum with the tonsils of the cerebellum * results in CSF blockage * Medullary ischemia and cardiorespiratory collapse

Question 41

Identify

Answer 41