The document discusses diagnostic radiology of the central nervous system. It begins with an outline and overview of normal brain anatomy and imaging features. It then describes basic features seen in common brain lesions including hydrocephalus, brain atrophy, necrosis, calcification, and mass effect. Specific pathologies covered include brain tumors, cerebrovascular diseases like hemorrhage, aneurysms, and infarction, as well as traumatic brain injuries such as epidural and subdural hematomas. Key imaging findings on CT and MRI for various acute and chronic stages are highlighted.

1. Diagnostic Radiology of Central Nervous System Raphael B. Jiang, Section of Diagnostic Radiology Sun Yat-Sen University First Affiliated Hospital

4. Falx cerebri Tentorium cerebelli Normal Imaging Anatomy of Brain Meninges

5. Falx cerebri Dura mater Arachnoid Subarachnoid space Pia mater Arachnoid granulation S. sagittal sinus Normal Imaging Anatomy of Brain Meninges

6. Normal Imaging Anatomy of Brain Meninges Falx and Tentorium Iso-/-mildly hyperdense compared with cortex on CT Hyperdense when calcified Markedly enhanced after iodine contrast Hypointense in T 1 WI and T 2 WI Homogeneity in signal intensity Markedly enhanced after Gadolinium

8. T 1 WI T 2 WI Normal Imaging Anatomy of Brain Cerebral Hemisphere

9. Frontal lobe Centrum semiovale Parietal lobe Longitudinal fissure Superior sagittal sinus FL CS PL LF SSS SECTION AT CENTRUM SEMIOVALE Normal Imaging Anatomy of Brain

10. Normal Imaging Anatomy of Brain Basal Ganglia Clusters of neurons, located deep in the brain Caudate nucleus, putamen, globus pallidus, substantia nigra CT and MR finding Basal ganglia and Thalamus — gray matter density/intensity Internal and External capsule— white matter density/intensity

11. Normal Imaging Anatomy of Brain

12. SECTION AT BASAL GANGLION Caudate Nucleus Head Putamen Thalamus I nternal Capsule External Capsule Falx Cerebri Normal Imaging Anatomy of Brain CNH PU EC FC TH IC

13. Caudate Nucleus Head Putamen Thalamus I nternal Capsule External Capsule Falx Cerebri SECTION AT BASAL GANGLION Normal Imaging Anatomy of Brain CNH PU EC FC TH IC

14. Normal Imaging Anatomy of Brain Brain Stem Mid-brain, pons and medulla oblongata CT appearance Brain stem nuclei not identifiable Surrounded by fluid-density cistern MR finding B rain stem nuclei Mildly hypointense on T 1 WI, hyperintense on T 2 WI White matter fiber— a slightly high intensity signal M ildly hyperintense on T 1 WI, hypointense on T 2 WI

15. SECTION AT OPTICAL CHIASM Gyrus Rectus Sylvian Fissure Hippocampus Mid- brain Aqueduct of Sylvius Optical Chiasm Occipital L S. Cerebellar Vermis Normal Imaging Anatomy of Brain GR OC MB OL SF HI AS SCV

16. Normal Imaging Anatomy of Brain Cerebellum CT appearance Gray and white matter can be distinguished Cerebellar tonsils and vermis slightly denser than other parts MR finding Signals of cortex, medulla and nuclei similar to those of brain

17. SECTION AT FOURTH VENTRICLE Occipital Lobe Cerebellar Hemisphere Pons Temporal Lobe Trigeminal Nerve Fourth Ventricle Normal Imaging Anatomy of Brain PO CH OL TL TN FV

18. Normal Imaging Anatomy of Brain

19. Corpus callosum Thalamus Aqueduct of Sylvius Fourth Ven. Mid-brain Pons Cerebellum Medulla oblongata SECTION AT MID-SAGITTAL PLANE Th AS Ce FV CC Mb Po MO

20. Lateral Ven. Third Ven. Corpus Callosum Insula Temporal Lobe LV IN TL CC TV SECTION AT LATERAL & THIRD VEN.

22. Normal Imaging Anatomy of Brain

23. Internal Carotid Artery Anterior CA Middle CA Posterior CA Basilar A. Anterior&Posterior Com. A Normal Imaging Anatomy of Brain ICA MCA PCA BA ACA

24. Normal Imaging Anatomy of Brain

25. Superior Sagittal Sinus Straight Sinus Confluence of sinuses Inferior Sagittal Sinus Normal Imaging Anatomy of Brain Transverse Sinuse Sigmoid Sinus

26. Normal Imaging Anatomy of Brain

28. Basic Features of Brain Lesions Hydrocephalus The term hydrocephalus is derived from the Greek words "hydro" meaning water and "cephalus" meaning head As the name implies, it is a condition in which the primary characteristic is excessive accumulation of fluid in the brain The excessive accumulation of CSF results in an abnormal widening of spaces in the brain called ventricles This widening creates potentially harmful pressure on the tissues of the brain

30. Normal CSF flow passage Lateral V – (Foramina of Monro) – Third V – (Aqueduct of Sylvius) – Fourth V – (Median aperture & Luschka Foramina) – Subarachnoid Space – (Arachnoid Granulations) – Superior SS

32. Classification Non-communicating Communicating Basic Features of Brain Lesions Hydrocephalus

37. Communicating Hydrocephalus

46. CHONDROMA MENINGIOMA

54. Astrocytoma Grade 1

55. Astrocytoma Grade 2

56. Astrocytoma Grade 2

57. Glioblastoma multiforme(Malignant)

59. 60Y/F Lung Adenocarcinoma

60. Neoplasm, metastasis, renal cell primary

67. Neoplasm, schwannoma, cerebellopontine angle

75. 14 D later

76. 2 days after first CT

77. Acute stage intracerebral hemorrhage

78. 16 D later

81. Internal carotid artery aneurysm

82. Internal carotid-siphon aneurysm

95. Acute epidural hematoma, fusiform high density beneath Frontoparietal bone plate (white arrow) , liquid-plane (black arrow) Fracture in bone window ( white arrow)

96. MRI Acute stage epidural hematoma

100. Acute stage subdural hematoma ， banded high density beneath the skull plate in left frontoparietal (black arrow)

102. MRI Subacute stage subdural hematoma , cortical vein is stripped from the skull

103. CT vs MRI Traumatic Brain Injury Subdural Hematoma Acute stage CT High desity MRI Isointense CT Advantage Subacute stage CT Iso-density MRI Hyperintense MRI Advantage Chronic stage CT Low density Like CSF MRI Hyperintense MRI Advantage

104. Subacute stage subdural hematoma CT : compression displacement of the right occipito-temporal sulcus MRI : hyperintense FLAIR : subarachnoid hemorrhage MRI is superior to CT in display iso-density hematoma

105. Subdural hematoma (isodense to brain)1 1 M later

106. 17 D later

110. Acute cerebral contusion, there are low-density edema with flake high-density shadow(Asterisk), accompanied with subarachnoid hemorrhage in the suprasellar pool, sylvian cistern and around the right falx cerebri(black arrow). The gas in the suprasellar pool indicates basal skull fractures(black arrowhead).

112. IR/T2WI ， Oxyhaemoglobin in Hematoma Isointense ， Edema with mass effect

113. Acute c erebral contusion Intracerebral hemorrhage and subarachnoid hemorrhage MRI is superior to CT in showing subarachnoid hemorrhage

116. questions Headache 4 months No traumatic history

117. Acute onset of headache Hypertension for 10 years

118. Acute onset of left hand numbness CT 1 15 D later

119. MRI 2

120. Subacute hemorrhage