2. Neuropathology of Injury

3.  protection  expansion  no lymphatics  tight junctions  tight junctions & astrocyte processes BBB

4. Neuropathology of Injury  capillaries not fenestrated [except choroid plexus]  end arterioles  minimal interstitial space  minimal perivascular space  minimal connective tissue [collagen and elastin]

5. CNS TRAUMA Concussion : temporary loss of function - unconsciousness for brain paralysis for spinal cord

6. CNS TRAUMA Contusion : disruption of architecture with haemorrhage at impact site or distant site

7. CNS TRAUMA Laceration : severe and permanent disruption of tissues with haemorrhage and necrosis

8. Haemorrhage

9. Acute brain swelling and unregulated vasodilation

10. Myelomalacia - necrosis or softening of spinal cord Type-1 disk protrusionHaemorrhagic myelomalacia

11. RAISED INTRACRANIAL PRESSURE oedema haemorrhage abscess tumour generalised inflammation increased CSF production decreased CSF drainage generalised signs

12. Question: Which of the characteristics listed earlier would alter the production, removal and consequences of cerebral oedema? Oedema = escape of fluids, or failure to recirculate CEREBRAL AND SPINAL CORD OEDEMA

13.  protection  expansion  no lymphatics  tight junctions  tight junctions & astrocyte processes BBB

14.  protection - p  expansion  no lymphatics  tight junctions  tight junctions & astrocyte processes BBB

15.  protection - p  expansion - c  no lymphatics  tight junctions  tight junctions & astrocyte processes BBB

16.  protection - p  expansion - c  no lymphatics - r  tight junctions  tight junctions & astrocyte processes BBB

17.  protection - p  expansion - c  no lymphatics - r  tight junctions – p & r  tight junctions & astrocyte processes BBB

18.  protection - p  expansion - c  no lymphatics - r  tight junctions – p & r  tight junctions & astrocyte processes BBB – p & r

19.  capillaries not fenestrated [except choroid plexus]  end arterioles  minimal interstitial space  minimal perivascular space  minimal connective tissue [collagen and elastin]

20.  capillaries not fenestrated – p & r [except choroid plexus]  end arterioles  minimal interstitial space  minimal perivascular space  minimal connective tissue [collagen and elastin]

21.  capillaries not fenestrated – p & r [except choroid plexus]  end arterioles - p  minimal interstitial space  minimal perivascular space  minimal connective tissue [collagen and elastin]

22.  capillaries not fenestrated – p & r [except choroid plexus]  end arterioles - p  minimal interstitial space - c  minimal perivascular space  minimal connective tissue [collagen and elastin]

23.  capillaries not fenestrated – p & r [except choroid plexus]  end arterioles - p  minimal interstitial space - c  minimal perivascular space - c  minimal connective tissue [collagen and elastin]

24.  capillaries not fenestrated – p & r [except choroid plexus]  end arterioles - p  minimal interstitial space - c  minimal perivascular space - c  minimal connective tissue - ? [collagen and elastin]

25. Oedema = escape of fluids, or failure to recirculate CEREBRAL AND SPINAL CORD OEDEMA Vasogenic oedema vessels protein rich astrocytes  i/s space trauma, vascular, masses

26. Oedema = escape of fluids, or failure to recirculate CEREBRAL AND SPINAL CORD OEDEMA Cytotoxic oedema glial cell swelling protein free fluid BBB intact global hypoxic, ischaemic, T/N/M, genetic

27. BRAIN SWELLING * brain abscess in a calf * Coenurus cerebralis cyst forebrain of sheep * astrocytoma, Boxer dog * feline infectious peritonitis panencephalitis in a cat * head trauma + cerebral oedema in a goat kid * thiamin-responsive, cerebral cortical necrosis in a lamb ↑ tissue / fluid  2 o fluid and pressure changes  fatal:

28. Herniation of brain tissue right cerebral swelling  to left under falx cerebri pressure on thalamus

29. Herniation of brain tissue right cerebral swelling  caudally under tentorium cerebelli pressure on midbrain

30. further swelling  cerebellum through foramen magnum Herniation of brain tissue  pressure on medulla oblongata

31. VASCULAR AND CIRCULATORY LESIONS blood supply Brain - carotid and vertebral arteries, circle of Willis anastomoses pia-arachoid, then end arteries collateral supply poor

32. Spinal cord - vertebral aa. (C), radicular aa. (T-L)  ventral spinal a. central grey matter-branches of ventral spinal a. white matter - meningeal vs. via end arteries VASCULAR AND CIRCULATORY LESIONS blood supply

33. Vascular and circulatory lesions from:- VASCULAR AND CIRCULATORY LESIONS Vasculitis, eg EHV-1 arteritis in a horse

34. Vascular and circulatory lesions from:- VASCULAR AND CIRCULATORY LESIONS Thrombo-embolisim, eg Salmonella septicaemia in pigs

35. Vascular and circulatory lesions from:- VASCULAR AND CIRCULATORY LESIONS Hypoxia/ischaemia, eg neonatal seizures in a foal anaesthetic accident in a dog

36. Vascular and circulatory lesions from:- VASCULAR AND CIRCULATORY LESIONS Coagulopathies, eg DIC in septic mastitis

37. VASCULAR AND CIRCULATORY LESIONS Question: Why should grey matter be more susceptible than white mater to many vascular and circulatory insults?

38. VASCULAR AND CIRCULATORY LESIONS Infarction