This document summarizes CT and MRI findings for various central nervous system conditions. It describes normal anatomy and imaging appearances of common intracranial tumors, vascular diseases, and traumatic injuries. Key points covered include characteristics of tumors like meningioma, astrocytoma and metastases. It also outlines imaging features of hemorrhage, infarction, aneurysms and skull fractures.

1. CT&MRI of Central nervous system Dept. Radiology, the 2nd affiliated hospital, Sun Yat-Sen University Huang Sui Qiao

3. CT scanner

5. Magnetic Resonance Imaging

8. MR signal charateristics T2WI T1WI

9. MR signal charateristics Fat supression Liquid supression

10. Normal anatomical structure of head on CT Brain stem; cerebellum;suprasellar cistern; lateral sulcus; quadrigeminal cistern; lateral ventricle; basilar ganglion

11. Normal anatomical structure of head on CT Gray matter; white matter; cortex; frontal lobe; occipital lobe; parietal lobe; temporal lobe; internal capsule ; thalamus; falx

12. Normal anatomical structure of head on MRI

13. T2WI

14. T1WI

15. Flair sequence

16. T2WI(coronal section ）

17. T1WI （ sagittal section ） Corpus callosum; optic chiasm; pituitary gland; medulla oblongata

22. 一、 Direct signs 1. tumor or occupying lesion. 2. abnormal density or signal. 3. enhancement in different degree on enhanced scan. CT and MRI Signs for diagnosis of intracranial tumors 、

23. 二、 indirect signs 1. shift of near structures 2. edema in brain tissue near tumor 3. intratumoral bleed 4. intratumoral calcification 5. bone changes

26. Grading I astrocytoma Plain CT

27. Grading I astrocytoma T 1 WI T 2 WI

28. Grading I astrocytoma T2W Gd+ Gd+ MR:39547

31. Grading IV astrocytoma MR:39985 T2W T1W Gd+

32. Grading IV astrocytoma MR:39985 T2W Gd+ T2W Gd+

33. MR ： 53847 Grading IV astrocytoma

35. Multiple metastases

36. Metastasis from lung cancer uncontrast contrast

37. Metastasis from lung cancer uncontrast contrast

38. Lung cancer and brain metastases MR:39491

42. Left parietal meningioma Plain CT Contrast CT Round high density mass Obviously and evenly enhanced

43. Right parietal meningioma Plain T1WI Contrast T1WI

44. T2WI AND contrast T1WI

45. meningioma T2WI T1WI Gd-T1W

47. Left acoustic schwannoma

48. Left acoustic schwannoma T2WI T1WI Contrast T1WI

49. Left acoustic schwannoma

50. Right acoustic schwannoma T1WI Contrast T1WI

51. Right acoustic schwannoma Contrast T1WI

55. Acute hemorrhage （ high density on CT ）

56. Acute hemorrhage （ high density on CT ）

57. Subacute hemorrhage Density lower than acute stage with unclear margin

58. acute/subacute hemorrhage acute subacute T2WI T1WI

59. Change from acute to subacute stage （ CT low density hemorrhage ） CT after bleed CT 2W latter MRI 2W latter

60. Chronic intracranial hemorrhage

66. Aneurysm at left internal carotid A

67. Aneurysm at left internal carotid A

68. T1WI-contrast T1WI-contrast

69. Aneurysm at left internal carotid A

70. Aneurysm at left middle cerebral A

71. CT&MRI diagnosis of cerebral infarction

74. MR:44396 Within 24h After 3 days After 2 weeks Acute cerebral infarction

75. MR:44396 MR&CT appearances of acute cerebral infarction Within 24h after 3 days after 2 weeks

76. MR:44396 MR&CT appearances of acute cerebral infarction T2WI T1WI Flair

77. MR:44396 MR&CT appearances of acute cerebral infarction Flair T1WI T2WI

78. Acute infarction MR ： 66335 CT ： 122740 M 39 ， CT （－）

79. Acute infarction MR ： 66335 CT ： 122740 M 39 ， CT （－）

80. Acute infarction MR ： 66335 CT ： 122740

81. Acute infarction DWI MR ： 66335 CT ： 122740

82. Subacute/chronic infarction—T2WI

83. T2WI--Cor

84. Chronic infarction at brain stem and cerebellum—T2WI

85. Chronic infarction at brain stem and cerebellum—T1WI

86. CT&MRI diagnosis of head trauma

90. acute epidural hematoma at left frontal lobe

91. acute epidural hematoma at right frontal lobe

92. Acute epidural hematoma at temporal-parietal lobe

94. Subacute hematoma at left frontal lobe

95. Subacute hematoma at left frontal lobe

96. Subacute hematoma at left frontal lobe

98. Acute subdural hematoma at right frontal-temporal area

99. Subacute subdural hematoma at left frontal-temporal area

100. Subacute subdural hematoma at left frontal-temporal area

101. Subacute subdural hematoma at left frontal-temporal area

102. Subacute subdural hematoma at left frontal-temporal area

103. Chronic subdural hematoma at left frontal lobe

105. Contusion at frontal lobe

106. Contusion at both sides of frontal base

107. Contusion at temporal lobe

109. Contusion and epidural hemorrhage at both temporal lobe and frontal lobe

110. Contusion and epidural hemorrhage at both temporal lobe and frontal lobe

111. Multiple contusions at both sides of frontal and temporal lobes

112. Multiple contusions at both sides of frontal and temporal lobes

113. THANK YOU