T1L17 neuropathy

Question 1

layers of the meninges

Answer 1

(aponeurosis
periosteum
bone)

dura mater >
arachnoid > meninges
pia >

Question 2

CS fluid

Answer 2

150mls

• produced by chroid plexus- 450m per 24hrs
• reabsorbed by arachnoid granules in subarachnoid space
• metabolic importance
• cushioning of the csf
• role in immune regulation and defense
• cerebral autoregulation of flow

Question 3

CSF circulation

Answer 3

see pic s9

Question 4

hydrocephalus

Answer 4

1. communicating
   - impaired reabsorption at arachnoid granules
   - too much produced
2. non communicating
   - obstruction of ventricles

RAISED INTRACRANIAL PRESSURE

Question 5

raised intracranial pressure

Answer 5

CSF above 200mmH2O

• increase CSF volume (hydrocephalus)
• intracranial space occupying lesion eg tumour, haemorrhage, abscess)
• cerebral oedema

consequences- HERNEATION

• subfalcine (across edge of falx cerebri)
• transentorial (across edge of tentorium cerebri)
• tonsillar (across foramen magnum)

Question 6

space occupying lesions

Answer 6

• extradural/epidural haemorrhage
• subdural haemorrhage
• subarachnoid haemorrhage
• intracerebral haemorrhage

ischaemic infarct with subsequent oedema or haemorrhage
neoplasm/abcess

Question 7

head trauma

Answer 7

skull fracture
parenchymal injury:
- contusion (bruising)
- laceration (penetration or tearing)
- diffuse axonal injury
- vascular injury

coup and contracoup (blunt trauma damages front and back of brain)

Question 8

vascular injury

Answer 8

extradural- severe trauma with arterial laceration
subdural- trauma may be minor in atrophy
subarachnoid rupture of saccular aneurysm
intraparenchymal from hypertension

Question 9

subarachnoid haemorrhage

Answer 9

messy as fuck- usually around circle of willis

Question 10

intracerebral haemorrhage

Answer 10

not good ovi

Question 11

cerebral oedema

Answer 11

vasogenic- increased vascular permeability

cytotoxic- neuronal, glial or endothelial cell damage

Question 12

cerebral infarct

Answer 12

ischaemic stroke
causes hypoxia

ischaemic infact histology:

• red neurons
• shrinkage of cell body
• loss of nucleoli
• eosinophilia of cytoplasm

Question 13

brain neoplasms

Answer 13

75% primary (25% metastatic)

• gliomas
• neural tumours
• meningiomas
• poorly differentiated neoplasms
• primary CNS lymphoma
• metastasis from lung/breast/kidney/gi
• peripheral nerve tumours ef schwanoma

Question 14

infections

Answer 14

• meningitis (bacterial/viral/fungal/ malaria, lyme disease)
• abscess (usually bacterial)
• encephalitis (viral)
• localised e toxoplasmosis

Question 15

degenerative conditions

Answer 15

• neurodegenerative (eg alzheimers)
• demyelinating eg ms
• genetic metabolic diseases
• toxic and acquired metabolic diseases
• spinocerebellar degenerative diseases