1. Imaging of the CNS

2. Contents Diagnostic tools Anatomical localization: Brain Diseases:
- Infection
- Tumor
- Trauma
- Stroke
- Cord compression

3. Tools
Plain film CT MR
Angiography

4. Plain radiography

5. 5 densities Air Fat Soft tissue (water,muscles,etc)
Bone, calcification
Metallic

6. Advantage & I/C Adventage - Convenience - Safe - Fast - Availability
Indication
Fracture skull
Increase ICP
Intrasellar mass
Osteolytic/ osteoblastic lesion
Calcifying pathology

7. View and positioning

8. PA Petrous pyramid อยู่ภายในกระบอกตา Frontal bone and parietal bone
Frontal sinus
Nasal cavity
Mandible
Roof of orbits

9. Lateral skull Cranial vault Suture : coronal and lambdoid
Occipital bone
Sellar turcica
Floor of cranial fossa
Clivus
Nasopharyngeal soft tissue
Sphenoid air sinus
lateral of calvarium
lateral of mandible
Cervical spine 1st-2nd

10. Lateral Outer table Suture Diploic space Sellar turcica Inner table
External occipital
protuberance
Sphenoid air sinus

11. Caldwell view
Orbital wall
Frontal and ethmoid sinuses
Mandible

12. Ethmoid sinus
Maxillary sinus
Caldwell view
Orbital wall

13. Towne’s view Occipital bone Lamdoid suture Foramen magnum
Petrous ridge และ mastoid sinuses
Zygomotic arch
Mandible ส่วน head, neck และ rami

14. Waters’ view Facial bone Orbital roof
Maxillary, frontal and ethmoid sinus

15. Waters’ view
Frontal sinus
Orbital wall
Maxillary sinus

16. Paranasal sinuses
Water’ s view
Caldwell view

17. Air-fluid level at both maxillary and both frontal sinuses
Paranasal sinusitis
Air-fluid level at both maxillary and both frontal sinuses

18. Linear fracture skull right parietal bone

19. Outer table destruction : histiocytosis X
Nasal bone
Fx nasal bone
Outer table destruction : histiocytosis X

20. Normal sella turcica Anterior clinoid Posterior clinoid Dorsum sellae
Floor of sella

21. “loss of dorsum sella sign”
ICP
“loss of dorsum sella sign”

22. Pituitary tumor
“Double floor sign”

23. Large intrasella mass 1 3 2
“ballooning sella”

24. CT : Pituitary tumour
CECT

25. CT scan

26. CT /Spiral CT/ MDCT

27. CT scan Advantage - Axial imaging
- Reconstruction, reformatted to coronal, sagittal planes
- Providing contrast- noncontrast study
- Differentiation tissues by densities(HU)
- Additional software: CTA, CTV, 3D, CTP etc.

28. Indication Trauma case 1st line imaging of Stroke Infection Tumor
Intracranial calcification
C/I: pregnancy, contrast enhancement injection: limited in patient with azotemia

29. Attenuation number of CT (HU) Hounsfield Units
CSF = 0-20 HU.
Gray matter = 40 HU.
White matter = H
Clot blood & hematoma = HU.
Calcification and bone = HU.
Fat = HU.
Air = >- 600 HU.
Density ของ lesion ใดๆจะดูเทียบกับ gray matter

30. Normal CT brain Gray matter White matter Basal ganglia cerebellum
Thalamus

31. Normal CT brain : Ventricular system
Temporal horn
Frontal horn
Lateral ventricle
4th ventricle
Occipital horn

32. Physiologic calcification
Pineal gland
Age > 10 year
Size < 10 mm.
Basal ganglia
Middle aged
Young aged : hypoxia or abnormal serum Calcium
Choroid plexus
Dura
Falx cerebri
Calcification of diaphragmatic sellae

33. Enhancement by contrast media
Abnormal blood brain barrier (BBB)
Identify vascular and dural structures
Differential pathology by pattern of enhancement

34. DSA

36. ANGIOGRAM – MCA BIFURCATION ANEURYSM

37. MCA aneurysm

38. 25-YEAR-OLD NORMOTENSIVE MAN WITH UNEXPLAINED ICH
LT ICA ANGIOGRAM – AVM

39. Indication Gold standard for vascular imaging ( ex. Aneurysm, AVM)
Arterial / venous
Risk=1%
C/I : azotemia, pregnancy

40. MRI machine

41. MRI Magnet Field : 0.5-3Tesla Pulse sequences : Spin Echo ( SE)
Parameters : T1
: T2
: TR
: TE

42. Advantage MRI Multiplanar imaging ( axial/coronal/sagittal/any planar)
No radiation
No bony artifact
Safer contrast agent (Gadolinium)
Best for analysis: posterior fossa and leptomeningeal lesions

43. MRI- three planars
Axial Coronal Sagittal

44. Contraindications Implantable Cardiac defibrillator Pace Maker
wt. > 136 Kg
Severe Claustrophobia
Pregnancy (+/- )
Cochlear Implant
Aneurysm Clips
Ferromagnetic eye prosthesis / F.B.

45. SIGNAL INTENSITY(SI) Tissue T1W T2W intermediate high high low
intermediate intermediate
low high
Intermediate intermediate
high high
BRAIN : GM
: WM
Muscles
Nerve :dorsal root
:ventral
CSF
Fat
Pituitary: anterior
posterior

46. T1WI

47. T2WI

48. MRI of brain tumor
T2W
T1W-GD
T1W