CNS Trauma & Hydrocephalus

Question 1

Components of the brain

Answer 1

-Cerebrum
- Cerebellum
- Brainstem- Midbrain, Pons & Medulla

Question 2

Histology of the brain

Answer 2

Neurons - dendrites, body, axon & synapse
Glia - Astrocytes, Oligodendrocytes, Microglia & Ependymal cells

Question 3

Meninges

Answer 3

1. Dura - Outer most dense collagenous tissue
2. Arachnoid- Middle loose connective tissue
3. Pia mater - Inner most layer

Question 4

Uniqueness of the brain

Answer 4

1. Closed box - pathological inc. ICP and its consequences
2. Autoregulation of blood flow - Unable to autoregulate after a limit
3. BBB - Some drugs cant cross
4. Little/ No lymphatics - Impaired resorption of edema fluid
5. Functional localization - Focal neurological deficits

Question 5

Cerebral Edema

Answer 5

Accumulation of excess fluid within the brain parenchyma

Question 6

types of Cerebral edema

Answer 6

1. Vasogenic
2. Cytotoxic

Question 7

Vasogenic Edema

Answer 7

Disruption of BBB –> Fluid from vascular component –> Extracellular space

Question 8

Cytotoxic edema

Answer 8

Injury to neuronal, glial or endothelial cell membranes –> Inc in intracellular fluid

Question 9

Causes of vasogenic edema

Answer 9

• Meningitis, encephalitis, trauma & metastasis
• Paucity of lymphatics

Question 10

Causes of cytotoxic edema

Answer 10

• Hypoxia/ ischemic insult
• Metabolic damage
• anything that injures the cells

Question 11

Hydrocephaluis

Answer 11

Accumulation of CSF within the ventricular system

Question 12

Causes of Hydrocephalus

Answer 12

1. Obstruction of flow of CSF
2. Impaired CSF resorption
3. Excess CSF production

Question 13

Clinical features of Hydrocephalus

Answer 13

• Inc head circumference (before suture closes)
• Ventricular expansion & Inc ICP (after suture closes)

Question 14

Types of Hydrocephalus

Answer 14

1. Non-communicating
2. Communicating
3. Ex vacuo
4. Normal pressure

Question 15

Cause & result of Non-communicating Hydrocephalus

Answer 15

Obstruction of CSF flow –> Blocks CSF circulation from ventricles to arachnoid space
- Only affected portion of ventricle enlarges

Question 16

Cause & result of Communicating Hydrocephalus

Answer 16

Poor absorption of CSF by arachnoid villi OR Overproduction of CSF
- Entire ventricle system enlarged

Question 17

Causes of Ex-vacuo Hydrocephalus

Answer 17

Infarctions or Neurodegenerative disorders –> Loss of brain volume
- Secondary inc in CSF volume

Question 18

Normal pressure Hydrocephalus

Question 19

Clinical features of Normal pressure Hydrocephalus

Answer 19

• Gait disturbances (Wobbly)
• Dementia (Wacky)
• Urinary incontinence (Wet)

WET, WACKY & WOBBLY

Question 20

Treatment of Normal pressure Hydrocephalus

Answer 20

Lumbar punctures/ CSF shunting

Question 21

Pseudotumor Cerebri / Idiopathic Intracranial Hypertension

Question 22

Epidemiology & etiology of Pseudotumor cerebri

Answer 22

• Overweight women of childbearing age
• Unknown cause

Question 23

Clinical features of Pseudotumor cerebri

Answer 23

Increased ICP
- headache
- diplopia (CN6 palsy)
- vomiting
- papilledema –> vision loss

Question 24

Treatment of Pseudotumor cerebri

Answer 24

• Lumbar punctures
• Acetazolamide
• Shunt

Question 25

Cerebral herniations

Answer 25

Displacement of brain tissue past rigid dural folds or through openings in the skull

Question 26

Clinical features of Cerebral herniation

Answer 26

- Compromised blood supply - Infarctions - Edema - Specific symptoms depending on area involved

Question 27

Types of Cerebral herniations

Answer 27

1. Subfalcine/ Cingulate 2. Tonsillar 3. Transtentorial/ Uncal

Question 28

Subfalcine herniation

Question 29

Tonsillar herniation

Question 30

Transtentorial herniation

Question 31

CNS Trauma

Answer 31

1. Skull bone fractures - Sharp vs blunt; Linear vs depressed vs basilar 2. Brain parenchymal injury - Concussion, contusion, lacerations, diffuse axonal injury, coup vs countercoup injury 3. Vascular injury - Epidural, Subdural, subarachnoid & intraparenchymal

Question 32

Linear fractures

Answer 32

Straight & sharply defined

Question 33

Depressed fracture

Answer 33

Fractured edges overlap

Question 34

Basilar fracture

Answer 34

Fractures in the base of the skull

Question 35

Concussion

Answer 35

Clinical syndrome of reversible altered consciousness ff head injury

Question 36

Etiology & Pathogenesis of Concussion

Answer 36

- Head trauma - Dysregulation of the Reticular Activating System in the brainstem - No parenchymal brain injury

Question 37

Clinical features of Concussion

Answer 37

- Transient loss of consciousness - Headache - Amnesia of event - Inability to focus or concentrate