Brain disease (Yr4)

Question 1

what are the divisions of the brain that disease can be localised to?

Answer 1

forebrain
brainstem
cerebellum
vestibular (central/peripheral)

Question 2

what mnemonic is used for creating a differentials list for disease?

Answer 2

Vascular
Inflammatory
Trauma
Anomalous
Metabolic
Inflammatory
Neoplastic
Degenerative

Question 3

what is the top differential for peracute onset brain disease?

Answer 3

vascular (stroke)

Question 4

what are the clinical signs of a lesions localised to the forebrain?

Answer 4

disorientation/depression
contralateral blindness (normal PLR)
normal gait
circling (ipsilateral), head turn, pacing, head pressing
decreased postural response in contralateral limbs
seizures
hemi-neglect syndrome
behavioural change

Question 5

what is the mentation of an animal with a forebrain lesion?

Answer 5

disorientated/depressed

Question 6

how does the gait of an animal with a forebrain lesion present?

Answer 6

normal (minimal effect)

Question 7

where can seizures be localised to?

Answer 7

forebrain

Question 8

what are the clinical signs of an animal with a cerebellar lesion?

Answer 8

normal mentation
ipsilateral abnormal menace (normal vision/PLR)
vestibular signs (head tilt)
ataxia, broad based stance, hypermetria
intention tremors
decerebellate rigidity

Question 9

what is the mentation of an animal with a cerebellar lesion?

Answer 9

normal

Question 10

what is decerebellate rigidity?

Answer 10

extension of forelimbs and opisthotonus

Question 11

what is opisthotonus?

Answer 11

extension of the neck

Question 12

what is the mentation of an animal with brainstem lesions?

Answer 12

stupor, depressed, comatosed

Question 13

what are the clinical signs of a brainstem lesion?

Answer 13

coma, stupor, depression
cranial nerve deficits
vestibular signs
paresis of limbs
decerebrate rigidity
respiratory/cardiac abnormalities
reduced postural response of all limbs

Question 14

what is decerebrate rigidity?

Answer 14

extension of all limbs and opisthotonus

Question 15

what is compliance in terms of intracranial pressure?

Answer 15

if intracranial pressure increases due to one factor such as blood supply another factor such as CSF will rapidly decrease to control the ICP, only works for small changes in ICP

Question 16

what happens to the brain if ICP increases too much?

Answer 16

herniates

Question 17

where can the brain herniate?

Answer 17

forebrain underneath the tentorium
cerebellum through foramen magnum

Question 18

what are the clinical signs of raised intracranial pressure?

Answer 18

mental status (depressed, comatosed)
cushings reflex
pupil size and PLR
abnormal posture (decerebrate/decerebellate)

Question 19

what controls the mental status of patients?

Answer 19

ARAS (ascending reticular activation system)

Question 20

what are the signs of cushings reflex?

Answer 20

bradycardia and hypertension

Question 21

why is cushings reflex not a good prognostic indicator for raised intracranial pressure?

Answer 21

usually occurs late on (due to ischaemia)

Question 22

how does pupil size change with raised intracranial pressure?

Answer 22

anisocoria
miosis
mydriasis

Question 23

what is anisocoria?

Answer 23

different sized pupils

Question 24

what is miosis?

Answer 24

small/constricted pupils

Question 25

what is mydriasis?

Answer 25

large/dilated pupils

Question 26

what are the main differentials for peracute onset presentation of brain disease?

Answer 26

vascular (stroke) toxic trauma (RTA...)

Question 27

what is the primary injury associated with head trauma?

Answer 27

physical disruption of parenchyma (concussions, lacerations...)

Question 28

what is the secondary injury associated with head trauma?

Answer 28

please of inflammatory mediators and haemorrhage leading to raised ICP

Question 29

what is used to assess the level of ICP in patients?

Answer 29

modified Glasgow coma scale

Question 30

how does the score of the modified Glasgow coma scale correlate with prognosis?

Answer 30

higher the score means a better prognosis

Question 31

what is the first thing to do in cases of raised ICP due to head trauma?

Answer 31

fluid therapy to restore blood volume and ensure adequate cranial perfusion pressures

Question 32

what type of fluid should be avoided with head trauma and raised ICP?

Answer 32

glucose containing fluids (poorer outcomes)

Question 33

what type of fluid should be used for ICP caused by head trauma?

Answer 33

hypertonic saline

Question 34

what should the blood pressure for a patient be?

Answer 34

100-140mmHg

Question 35

what should care be taken when giving patients with raised ICP due to head trauma morphine?

Answer 35

can cause emesis (straining further increases ICP)

Question 36

how should an animal with raised ICP due to head trauma be positions for recovery?

Answer 36

as up right as possible with no jugular compression to increase drainage from brain

Question 37

should steroid be given for head trauma?

Answer 37

no

Question 38

what are the main differentials for acute/subacute brain disease?

Answer 38

inflammatory/infectious metabolic neoplasia

Question 39

what are the three routes of entry for bacterial meningitis?

Answer 39

haematogenous direct invasion (inner ear, eyes, bones...) CSF

Question 40

what is the main finding in CSF with bacterial meningitis?

Answer 40

neutrophilic

Question 41

how common is bacterial meningitis in dogs?

Answer 41

rare

Question 42

what is the prognosis for bacterial meningitis?

Answer 42

guarded

Question 43

what causes hepatic encephalopathy?

Answer 43

acute/chronic liver failure usually due to portosystemic shunts

Question 44

what is the pathogenesis associated with hepatic encephalopathy?

Answer 44

hyperammonaemia neuroinflammation cerebral oedema

Question 45

what are the clinical signs of hepatic encephalopathy?

Answer 45

vague (PUPD, weight loss, GI signs...) forebrain (seizures, blindness, pacing...)

Question 46

how is hepatic encephalopathy treated?

Answer 46

lactulose antibiotics diet minimise contributing factors control seizures

Question 47

why is lactulose used to treat hepatic encephalopathy?

Answer 47

traps ammonia as non-diffusible ammonium in the intestine to decrease the absorption into the blood

Question 48

why are antibiotics used in the treatment of hepatic encephalopathy?

Answer 48

reduce number of ammonia producing bacteria in the gut

Question 49

how can diet be changed to control hepatic encephalopathy?

Answer 49

decrease protein and amino acid content of food (reduced gut derived ammonia)

Question 50

what are some possible causes of hypoglycaemia?

Answer 50

insulinoma, liver disease, insulin overdose, juvenile hypoglycaemia

Question 51

what are the clinical signs of hypoglycaemia?

Answer 51

lethargy, ravenous appetite, anxiety weakness/tremors seizures

Question 52

why is the brain the first place effected by hypoglycaemia?

Answer 52

has no glucose storage

Question 53

what are the main differentials for chronic brain disease?

Answer 53

degenerative neoplasia anomalous

Question 54

what is the main intra-axial (within brain tissue) neoplasm?

Answer 54

glioma

Question 55

what are the main extra-axial (non-brain tissue) neoplasms?

Answer 55

meningiomas choroid plexus tumors

Question 56

what is the main treatment options for brain neoplasias?

Answer 56

analgesia (paracetamol, gabapentin...)

Question 57

what is hydrocephalus?

Answer 57

abnormal dilation of ventricular system within the cranium

Question 58

what breeds are predisposed to hydrocephalus?

Answer 58

toy breeds

Question 59

what are the clinical signs of hydrocephalus?

Answer 59

domed head, abnormal behaviour, obtunded, circling, seizure, vestibular signs

Question 60

what is storage disease?

Answer 60

degenerative disease caused by lack of lysosomal enzymes in the brain so products build up

Question 61

what age do animals usually present with storage disease?

Answer 61

very early age (first few weeks of life)