1. HEAD INJURY E Woo

2. Non-penetrating head injury

3. Most controversial issues Are the deficits consistent with the injury? Malingering? Is there any pre-existing disease that may cause or contribute to his deficits? Should he be cared for at home? What is the remaining life expectancy?

4. Mild injury→mild deficits Severe injury→not necessarily severe residuals

5. Glasgow coma scale Eye opening (E) 4Spontaneous 3To questions/command 2To pain 1Nil Verbal response (V) 5Normal and oriented 4Confused speech 3Inappropriate speech 2Incomprehensible words 1Nil Motor response (M) 6Normal and following commands 5Localize pain 4Withdrawal to pain 3Flexor posturing 2Extensor posturing 1No response

6. Severity of head injury MildGCS 14 to 15 ModerateGCS 10 to 13 SevereGCS ≤ 9

7. Post traumatic amnesia (PTA) Mild less than 1 hour Moderate 1 to 24 hours Severe more than 24 hours

8. Retrograde amnesia how much the plaintiff can recall of what happened immediately before the accident variable, hence not a good guide for the severity of the head injury in general terms, for a mild injury, retrograde amnesia should be minimal

9. Fractures Vault - Linear - Depressed Base

13. Sites of hemorrhage Scalp hematoma Intracranial bleeding -intracerebral -intraventricular -subarachnoid -extradural -subdural -combination

14. ICH

15. EDH

16. SDH

17. SAH

18. PARENCHYMAL DAMAGE Contusion Diffuse axonal injury -shearing injury in acceleration/deceleration -no fracture or external wound -deep coma but normal intracranial pressure -punctate lesions throughout the white matter especially corpus callosum

19. Contusion

21. Diffuse axonal Injury

22. Vascular damage Dissection of internal carotid artery Carotid-cavernous fistula Pseudo-aneurysm

23. Dissection

24. Carotid-cavernous Fistula

25. Pseudo-aneurysm

26. Treatment Conservative Surgical - evacuation of hematoma/contusion - intracranial pressure monitoring

27. Late complications chronic subdural hematoma hydrocephalus CSF rhinorrhoea after skull-base fracture

28. Chronic subdural hematoma 4 to 6 weeks after accident, often mild injury Increasing headache Focal neurological deficits Burr-hole drainage Good prognosis (as distinct from acute subdural hematoma)

30. Hydrocephalus -a few months after accident -complicating subarachnoid/intraventricular hemorrhage -shunt operation (ventriculo-peritoneal) -prognosis depends on shunt

31. Radiological investigations CT scan in acute phase MR scan in chronic phase

32. Outcome (Glasgow outcome scale) Normal] Good recovery] Independent Moderate disability] Severe disability} Vegetative state} Dependent Death}

33. Residual disabilities Headache Dizziness Vestibular dysfunction - vertigo positional effect nystagmus Memory loss - absent-mindedness loss of recent memory Emotional disturbance - irritable anxious depressed Frontal lobe dysfunction - apathy aggressiveness disinhibition, impulsivity suggestibility executive dysfunction frontal release signs

34. Sequelae Physical - cranial nerve deficits - hemiparesis Cognitive - dementia Emotional/Psychiatric

35. Post-concussional syndrome following upon mild/moderate head injury headache, nonspecific dizziness, tinnitus, insomnia, irritability, anxiety no structural pathology on imaging studies good prognosis

36. Persistent vegetative state Total lack of awareness of self or environment No language function (expression/comprehension) Own sleep-wake cycles No purposeful or behavioural response to visual, auditory, tactile or noxious stimulus Incontinence Preserved brainstem reflexes May moan or groan May even cry or shed tears May blink Jerky myoclonic movements (spinal origin)

37. Minimally conscious state Some sign of awareness Follow simple commands Gestural or verbal yes/no response Intelligible verbalization Purposeful behaviours contingent to relevant environmental stimuli (not reflexive)

38. Assessment starts before plaintiff walks in and continues through history taking Cognitive - mini-mental state examination (MMSE) Physical: →eye movements →motor and sensory →reflex →co-ordination →gait

39. Malingering Cognitive - approximate answers - worsening MMSE over time Physical - nonphysiological distribution of weakness -Hoover’s sign -give-way weakness - bizarre gait Inconsistency of deficits Incompatibility with site/extent of lesion Discrepancy between history and examination Handwriting

40. Impairment of the whole person Guides to the Evaluation of Permanent Impairment (American Medical Association) Based on ability to perform activities of daily living A numerical range for deficits in cognition and physical abilities No provision for headache

41. Loss of earning capacity Depends on occupation

42. Duration of sick leave Mild to moderate cases – recover over 6 to 12 months Severe cases – recover over 1 to 2 years

43. Life expectancy Adverse factors →severe cognitive dysfunction →swallowing difficulties (tube feeding) →physical deficits (immobility) →incontinence →Seizure Does good supportive care prolong survival?

44. Persistent vegetative state Markedly reduced survival 2 to 5 years Survival beyond 10 years unusual

45. Future medical treatment usually none after 1 to 2 years for those with severe deficits, e.g. bedbound or PVS, follow-up every 3 months tests medications

46. Post-traumatic epilepsy Risk factors →severe injury (PTA > 24 hours) →depressed skull fracture →cerebral contusion →acute subdural or intracerebral hematoma →early epilepsy (occurring within first 7 days) Most (80%) do so within first 2 years

47. Seat belts reduce fatal injuries and severe injuries in survivors, each by a factor of about 4 times most marked reduction in head-on crashes head injuries caused by frontal impacts against windshield or dashboard greatly reduced belts protect against ejection from the car

48. Home care vs Institutional care In PVS/MCS cases

49. Pre-existing lesion – hypertension with intracerebral hemorrhage unknown but severe hypertension a minor injury or some form of physical stress/exertion common sites of hypertensive hemorrhage

50. ICH

51. Pre-existing lesion – aneurysm with subarachnoid hemorrhage Asymptomatic aneurysm Minor head injury Exertion

52. Pre-existing lesion – anticoagulant use for artificial heart valves anticoagulant at therapeutic level (not overdosed) minor head injury diffuse/multifocal hemorrhages