1. The document discusses the anatomy and imaging features of cerebrospinal fluid (CSF) cisterns and spaces. It describes the locations and contents of various cisterns such as the interpeduncular, chiasmatic, crural, ambient and cerebellomedullary cisterns. 2. Imaging findings of different pathological conditions are presented, including benign external hydrocephalus, subdural hematoma, hydrocephalus, atrophy and periventricular leukomalacia. Key distinguishing features between these entities are highlighted. 3. An overview of CSF spaces is given, outlining the appearance of normal, atrophic and edematous/hydrocephalic states.

1. DR/ Hytham Nafady

2. Cistern
• Widening of subarachnoid space created
by separation of pia and arachnoid.
Dura
Pia
Arachnoid
adherent to the skull
adherent to the brain surface
covers only superficial surface of
the brain

3. Cistern
• Widening of subarachnoid space created
by separation of pia and arachnoid.
Subarachnoid hemorrhage

6. P
M
IP
CH
SC
CM
VI
Q
PC
LT

11. P
M
IP
CH
SC
CM
VI
Q
PC
LT

13. P
M
CH
CM
VI
PC
LT

17. Perimesencephalic cistern
1. Interpeduncular C.
2. Crural C.
3. Ambient C.
4. Quadrigeminal C.

18. Perimesencephalic cistern
1. Interpeduncular C.
2. Crural C.
3. Ambient C.
4. Quadrigeminal C.

19. Perimesencephalic cistern
1. Interpeduncular C.
2. Crural C.
3. Ambient C.
4. Quadrigeminal C.

20. Perimesencephalic cistern
1. Interpeduncular C.
2. Crural C.
3. Ambient C.
4. Quadrigeminal C.

21. Perimesencephalic cistern
1. Interpeduncular C.
2. Crural C.
3. Ambient C.
4. Quadrigeminal C.

25. CSF cisterns
Median un-paired cisterns Para-median paired cisterns
1-Premedullary 12-Inferior CP angle
2-Prepontine 13-Superior CP angle
3-Interpeduncular 14-Crural
4-Chiasmatic 15-ambient
5-Lamina terminalis 16-Carotid
6-Pericallosal 17-sylvian
7-Quadrigeminal
8-Vellum interpositum
9-Superior cerebellar
10-Cisterna magna
11-Vallecula

26. Medullary cistern
premedullary cistern

27. Medullary cistern

28. PICA
Cn12
VA

29. Pontine cistern
pre-pontine cistern

30. Pontine cistern

31. Pontine cistern
Basilar A
Ant. Pontomesencephalic V
Petrosal V
Superior petrosal sinus

32. Pontine cistern

33. Pontine cistern
AICA
BA
Cn6 Cn6
BA

34. Pre-pontine arachnoid cyst

35. Interpeduncular cistern
basal cistern

36. Interpeduncular cistern

37. Interpeduncular cistern
Cn 3
Interpeduncular
cistern

38. Interpeduncular cistern

39. Basal v.
Interpeduncular V
DMCV Ponto-
mesencephalic V Basilar A.
Interpeduncular V
DMCV

40. Chiasmatic cistern
Suprasellar cistern

41. Chiasmatic cistern
Suprasellar cistern

42. Suprasellar arachnoid cyst

43. Liliequist membrane
The Liliequist membrane is the arachnoid
membrane separating the chiasmatic and
interpeduncular cisterns.

45. Liliequist membrane

46. CH
P
IP

47. Third
ventriculostomy

48. Third ventriculostomy

49. PNSAH
• Peri-mesencephalic Non-aneurysmal Sub-Arachnoid Hemorrhage.
• Pre-truncal Non-aneurysmal Sub-Arachnoid Hemorrhage.
• Brain stem = truncus cerebri.
• Low pressure bleeding.
• Source: perimesencephalic vein.

52. Lamina terminalis cistern

55. Pericallosal cistern

56. Pericallosal artery aneurysm

57. Subarachnoid
hemorrhage

58. Quadrigeminal cistern
vein of Galen cistern

59. Vein of Galen aneurysm

60. Precentral V
Precentral VPrecentral V

61. Precentral V

62. Quadrigeminal cistern
epidermoid cyst

63. Superior cerebellar cistern

66. Vellum interpositum cistern
(double layered tela choroidae)

67. Embryologic Basis for the Development and
Anatomy of the Cavum Veli Interpositi

68. Vellum interpositum cistern

69. Cavum vili
interpositi

70. Cavum villi interpositi Cavum septum pellucidum
& cavum vergae

71. Cisterna magna
Cerebellomedullary cistern

72. Mega cisterna magna
Mega
cisterna
magna

73. Vallecula cerebelli
Vallecula

74. Dandy walker variant

75. CP angle cisterns

76. CP angle cistern
AICA

77. Superior CP angle cistern
AICA
AICA
AICA
AICA

78. Inferior CP angle cistern
Cn
9/10
Cn 10
Cn 9

79. Inferior CP angle arachnoid cyst

82. Crural cisterns
Between the
Crus cerebri
(cerebral
peduncles
Uncus of
temporal lobe
Medially Laterally

84. AchA AchAAchA
SCA
PCA
PCA

86. Carotid cisterns

88. Sylvian cisterns

89. Ambient cisterns

90. Trochlear N.

92. PCA

94. Basal vein of Rosenthal

95. Basal vein of Rosenthal

96. Basal vein of Rosenthal

97. Cn 4
epidermoid

98. Trochlear N. schwannoma

99. Retro-thalamic cisterns
wings of ambient cisterns

101. Vellum interpositum
Retro-thalamic CisternRetro-thalamic Cistern
Sup.cerebellar Cistern

102. Overview of CSF spaces

103. Overview of CSF spaces
Normal:
All CSF spaces are visible
neither effaced or dilated.

104. Overview of CSF spaces
Normal:
All CSF spaces are visible
neither effaced or dilated.
Atrophy:
All CSF spaces are dilated.
Hydrocephalus:
Ventricles dilated.
Subarachnoid spaces
effaced.
Edema:
All CSF spaces are effaced.

105. Overview of CSF spaces
Normal:
All CSF spaces are visible
neither effaced or dilated.
Atrophy:
All CSF spaces are dilated.

106. Overview of CSF spaces
Normal:
All CSF spaces are visible
neither effaced or dilated.
Atrophy:
All CSF spaces are dilated.
Hydrocephalus:
Ventricles dilated.
Subarachnoid spaces
effaced.

107. Overview of CSF spaces
Normal:
All CSF spaces are visible
neither effaced or dilated.
Atrophy:
All CSF spaces are dilated.
Hydrocephalus:
Ventricles dilated.
Subarachnoid spaces
effaced.
Edema:
All CSF spaces are effaced.

109. Benign external hydrocephalus

110. 3 years10 months
Benign external hydrocephalus

111. Benign external hydrocephalus
benign enlargement of subarachnoid spaces in infancy
Etiology:
• Immature arachnoid granulations.
C.P:
• Macrocephaly.
• Normal developmental milestones.

112. 1. Widening of the bifrontal subarachnoid space and anterior
interhemispheric fissure (>5mm).
2. Usually normal subaracnoid space posteriorly.
3. No flattening of adjacent gyri.
4. The anterior fontanelle is frequently enlarged.
5. The ventricular system is within normal limits or slightly dilated.
6. There are no pressure effects on the surrounding brain tissue
or cerebral atrophy.
7. No blood products on MRI study.
8. another key distinction between benign enlargement of the
subarachnoid spaces and a subdural fluid collection is that in
the former the cortical veins will be adjacent to the inner table
of the calvarium on MR and ultrasound; whereas in the latter
the veins are displaced away from the inner table, as the
arachnoid membrane and subarachnoid space are displaced.

113. Benign external hydrocephalus

114. Benign external hydrocephalus

115. External hydrocephalus vs subdural hematoma

116. Hydrocephalus versus atrophy
Features that favor hydrocephalus
• Dilatation of the temporal horns
• Peri-ventricular interstitial oedema .
• intra-ventricular flow void from CSF movement on MR
• Widening of the third ventricular recesses : mid sagittal plane
• Upward bowing of the corpus callosum : mid sagittal plane
• Decreased mammillo-pontine distance : mid sagittal plane

117. Mid-sagittal findings of
hydrocephalus
• Widening of the third
ventricular recesses.
• Upward bowing of the
corpus callosum.
• Decreased mammillo-
pontine distance .

121. Periventricular
leukomalacia