CT scanning provides images of brain tissue based on density differences detected by x-rays. The images produced use Hounsfield units to represent densities on a scale where air is -1000 and bone is +1000. On CT, white matter appears darker than gray matter and CSF appears black. Common sequences seen on CT include axial, coronal, and sagittal cuts at various anatomical levels. CT is used to identify acute ischemic strokes within 12 hours by detecting hyperdense arteries, and in subsequent days can identify low density infarcts and hemorrhagic transformations. Chronic infarcts appear as well-defined low attenuation areas.

1. CT BRAIN - BASICS D.SUBBURAJ PROF.G .ELANGOVAN’S UNIT

2. CT Principle RING OF XRAY DETECTORS

5. air --- 1000 fat ---70 Pure water 0 Csf +8 White matter +30 Gray matter +45 blood +70 Bone/cacification +1000

8. LV FRONTAL HORN TEMBORAL HORN OCCIPITAL HORN FORAMEN OF MONRO 4 V AQUEDUCT OF SYLVIUS 3V trigone

9. COMMON SECTIONS AXIAL SECTIONS CORONAL SECTIONS SAGITTAL SECTIONS POSTERIOR FOSSA CUTS - ABOVE THE FORAMEN MAGNUM LEVEL -LEVEL OF THE FOURTH VENTRICLE -ABOVE THE FOURTH VENTRICULAR LEVEL - TENTORIAL SUPRATENTORIAL CUTS - THIRD VENTRICULAR LEVEL -LOW VENTRICULAR LEVEL -ABOVE THE VENTRICULAR LEVEL -FRONTAL HORN LEVEL -THIRD VENTRICULAR LEVEL -MID VENTRICULAR LEVEL -OCCIPITAL HORN LEVEL -MID SAGITTAL LEVEL -PARASAGITTAL LEVEL THROUGH THE LATERAL VENTRICULAR BODY -LATERAL ORBITAL LEVEL

10. ABOVE THE LEVEL OF FORAMEN MAGNUM VA MEDULLA TONSIL 4 V CM INT OCC PROT

11. LEVEL OF FOURTH VENTRICLE MCP CPCISTERN PONS 4V TEM HORN Optic nerve

12. LEVEL ABOVE FOURTH VENTRICLE SUPRA SELLAR CISTERN MB AMB CIST SYLV FISSURE 4V OLF SULCUS vermis

13. THIRD VENTRICULAR LEVEL

14. LOW VENTRICULAR

15. Above ventricle level

18. MCA ACA PCA

21. Water shed infarct

22. CEREBRAL ISCHEMIA

29. Dense mca sign

30. ‘ loss of insular ribbon’

31. M C A DOT SIGN

32. ATTENUATION OF LENTICULAR NUCLEUS

39. PCA INFARCT

40. MCA INFARCT

41. ACA INFARCT

42. WATERSHED INFARCT

43. Old infarct

44. H’gic infarct

45. Thank u