1. Neuroradiology of Stroke and Headaches

2. Learning Objectives Identify T1 and T2 sequences
Recall the normal anatomy of the intracranial circulation
Apply appropriate CT and MR imaging of the brain in acute stroke

3. Learning Objectives Differentiate acute from chronic infarct on CT
Classify primary and secondary headaches
Formulate appropriate imaging algorithms for headache

4. Learning Objectives
Recognize subarachnoid hemorrhage on noncontrast head CT
State common locations of intracranial aneurysms
Describe treatment options for patients with intrcranial aneurysms

5. What type of imaging modalities are used to evaluate the brain in patients presenting with acute stroke?

6. Axial NECT head

8. What is the most sensitive method for detection of acute ischemia in the brain?

9. Describe factors which influence which modality is chosen to image patients with acute stroke.

10. What modalities can be used to evaluate the cerebral vasculature?

11. Pros and Cons of Vascular Exams
MRA/MRV
CTA/CTV
Catheter based
Angiogram or Venogram

12. Pros and Cons of Vascular Exams
MRA/MRV
Noninvasive/Minimally Invasive (if iv contrast)
No radiation
No contrast
Exam times long
Cooperation needed/quality inconsistent
Not always available in some centers
CTA/CTV
Minimally invasive (iv required)
Quick
Immediately available
Radiation dose
Contrast required
Catheter based
Angiogram or Venogram
Gold standard
High resolution of vascular detail
Offers endovascular access if needed
Invasive
Morbidity/Mortality
Necessitates angiography team
Expensive

14. ACA
MCA
ICA
vert
PCA
basilar
SCA
AICA
PICA

16. ACA
MCA
ICA
basilar
PCA
vert

17. What vessel connects the anterior and posterior circulation
What vessel connects the anterior and posterior circulation? Where would you draw it?

19. Describe a clinical scenario where MRA is indicated.

20. lateral
oblique
coronal

21. MRV superior sagittal sinus superior sagittal sinus transverse sinus
torcula
sigmoid sinus
Internal jugular
superior sagittal sinus
transverse
sinus
Internal jugular
torcula
internal cerebral veins
straight sinus
sigmoid sinus
vein of Galen
MRV

22. How might this patient have presented?
Axial NECT head
How might this patient have presented?

23. Axial NECT head
What are the findings?

25. Normal extracellular space Normal
neuron
extracellular diffusion > intracellular diffusion
Cytotoxic Edema
in Infarction
swollen
neuron
Extracellular space
decreased and
diffusion limited

26. At what point after the onset of stroke like symptoms does DWI become positive?

27. 55 yo female with new right hemiparesis, right neglect and expressive aphasia

28. Explain the discordance in the findings between these two studies.
MRI Axial DWI
Axial NECT head

29. What is in your differential diagnosis?
67 yo male with 2 hours of new onset of right sided weakness.
What is in your differential diagnosis?

30. What imaging study would you order?

31. 67 yo male with 2 hours of new onset of right sided weakness

32. What occurred in the interval?
Coronal NECT head
Axial NECT head
What occurred in the interval?

33. What are the signs of mass effect?
Coronal NECT head
Axial NECT head
What are the signs of mass effect?

34. How does hemorrhagic transformation of ischemic infarct occur?

35. Acute vs. chronic
Axial NECT head
Coronal NECT head

36. Acute vs. chronic
MRI axial DWI
MRI axial T2
MRI axial ADC

37. What is in your differential diagnosis?
19 yo female c/o headache gradually worsening over 3 days and decreased visual acuity. She is obese, takes oral contraceptives and has papilledema on phys exam.
What is in your differential diagnosis?

38. What type of imaging examination should be ordered?

39. Axial NECT head

40. Normal
Patient

41. What are the patient’s risk factors?

42. What are other risk factors associated with venous sinus thrombosis?

43. Now let us turn to this patient’s MRI
Now let us turn to this patient’s MRI. What do we expect to see on the DWI?

45. Can you give examples of other secondary headaches?

46. What are examples of primary headaches?

47. What should be done next for this patient?
41 yo male with sudden onset of severe h/a. Denies history of h/a in past.
What should be done next for this patient?

48. When should a non-enhanced CT head be ordered in the clinical setting of headache?

49. 41 yo male with sudden onset of severe headache.
Axial NECT head

50. What imaging examination should be performed next?

51. What if the CT angiogram is negative?

52. What are the treatment options for ruptured aneurysm?

53. What are the advantages and disadvantages to each?

54. Axial NECT head
bone window
AP XR skull

55. What are the most common locations of intracranial aneurysms? Why?

56. How do aneurysms cause headaches?

57. What examinations can be used to detect aneurysms?

58. Aneurysm found on screening MRA. Where is it located?
MRA axial source images
MRA MIP

59. Who is at increased risk for developing aneurysms?

60. Who should be screened?

61. What is the preferred modality for aneurysm screening?

62. 52 y.o. male w/hx of 4 mm right paraophthalmic aneurysm found on CT angiography performed after high speed MVA resulting in skull base fractures.
Sagittal CT angiography
Coronal CT angiography

63. 54 yo female w/ long hx of h/a, photophobia and phonophobia
Primary or secondary headache?

64. What are the indications to order an MRI in the clinical setting of headache?

65. 54 yo female w/ long hx of h/a, photophobia and phonophobia

66. Primary or secondary h/a?
54 yo male with 2 wks of fever, malaise and h/a. Now has increasing right arm and right facial weakness. PMHx of IVDA which currently denies.
Primary or secondary h/a?

67. What is in your differential diagnosis?

68. What type of imaging study would you order?

69. T1
T1 gad
2 weeks fever, malaise and h/a. Now with increasing right arm and right facial weakness T2

70. How would you describe this lesion?
T1 gad
How would you describe this lesion?
MRI axial T1
MRI axial T1 gad T2
MRI axial T2
MRI axial DWI

71. How does the restricted diffusion shape your differential?
T1 gad
How does the restricted diffusion shape your differential? T1
T1 gad T2 T2
DWI

72. Why is this NOT an infarct?
T1 gad
Why is this NOT an infarct? T1
T1 gad T2 T2
DWI

73. End.