brain ct review

1. DR Mohammad Aburumman
Arab Board OF RADIOLOGY -
Fellow of I.R

2. BRAIN CT SCAN
PART I
REVIEW FOR ANATOMY AND
Common acute conditions
for clinician

3. SCHEME OF THE LECTURE
BASIC PRINCIPLES OF CT SCAN
NORMAL ANATOMY AS SEEN ON
CRANIUM CT SCANS
ILLUSTRATIONS

4. Basics :
• X-RAYS ARE ABSORBED DIFFERENTLY BY DIFFERENT
TISSUES
• Always describe CT findings as densities-
isodense/hypodense/hyperdense.
• Higher density = the appearance IS WHITER
• Lower density = the appearance IS DARKER
• Brain is the reference density
• Anything of the density as brain= isodense
• Higher density than brain= hyperdense ( BONE is
example)
• Anything darker than brain= hypodense( ie. CSF and air )

5. HOUNSFIELD UNITS
H.U ? !
Represent the density of tissue
Calculated automatically by Ct scan machine
processor by Place the marker on area of
interest

9. 30 H.U

10. 45 H.U

11. 1000
H.U

20. Petroclinoid lig. calcification

21. tentorium cerebelli

22. FALX CEREBELLI

23. FALX CEREBELLI

25. STROKE

27. I schaemic Stroke
1 st 6 Hours :
60% Normal
Vogue subtle Hypodensity .
Sulcal effacment
Loss of Grey/White matter Distinction ...
12-24 More prominant low attenuated
area .

28. Ischaemic Stroke
 After 24 hours
 Well demarcated low attenuation .
 3-5 days
 Mass effect which may gone by 2-4 weeks .
 LongTerm
 Encephalomalcia

31. IS CONTRAST NECESSARY ??

32. Hemorrhagic Stroke

33.  Sub Dural and Epidural Hematoma
 Usually traumatic >>>
 Subdural
 Venous bleed
 due to stretching and tearing of bridging
cortica

34.  Epidural
 Arterial bleed
 The source of bleeding is usually a torn
meningeal artery (most commonly, the
middle meningeal artery)
 meningeal artery.
 Skull Fracture .
 >95% are supratentorial
 temporoparietal: 60%

36. EDH

37. S.A.H

38. TO
BE
CONTINUE

39. THANKYOU