Cerebral Veins (Deep & Superficial + Diploic and Emissary Veins) | Anatomy — Transcript

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1. 0:03In the last video, we covered the anatomy of the dural sinuses;
2. 0:06Now let's go ahead and cover the rest of the veins you'll find supplying the structures
3. 0:10of the brain.
4. 0:11So, In this video, we're first going to talk about the cerebral veins
5. 0:15Which include the deep cerebral veins and the superficial cerebral veins.
6. 0:20Then we'll talk briefly about the diploic veins and then the emissary's veins.
7. 0:25And again, in the previous video, we talked about the dural sinuses; so if that topic
8. 0:29is unfamiliar to you I'll put a link to a playlist that covers
9. 0:33the venous drainage of different parts of our bodies.
10. 0:36Alright.
11. 0:37So, the easiest way to understand the veins of the systemic circulation is to divide them
12. 0:42into their own systems.
13. 0:44So the veins of the heart form their own system We have the Veins of the Inferior Vena Cava,
14. 0:49which is responsible for supplying the lower half of the body
15. 0:53Veins of the superior vena cava for the upper half of the body
16. 0:57And the portal system, which drains nutrients from the intestines
17. 1:01and waste products from the spleen and dumps them into the liver to be processed,
18. 1:05which then flow into the inferior vena cava again.
19. 1:08So these are the 4 main systems of veins we have in our bodies.
20. 1:13And so, the cerebral veins are a part of the superior vena cava because they drain into
21. 1:18it eventually.
22. 1:19So here are the dural veins we went through last time.
23. 1:22All the main dural sinuses that exist in our brain.
24. 1:25Now let's expand on that and make a cross-section right across the cranium
25. 1:30As you see here.
26. 1:31Remove the upper half.
27. 1:33And look at the skull from this perspective.
28. 1:35We'll see this.
29. 1:36So from this perspective; we can see the Straight Sinus
30. 1:39The Transverse Sinus The sigmoid Sinus,
31. 1:42The inferior petrosal Sinus and the Superior petrosal Sinus
32. 1:47Cavernous Sinus, and between them the Anterior and the posterior intercavernous
33. 1:52sinuses Then there's the basilar plexus and the sphenoparietal
34. 1:56Sinus.
35. 1:57And then here we see the tentorium cerebelli; which lies between the Cerebellum and the
36. 2:00Cerebrum Alright;
37. 2:03So let's work from there, and start breaking down the cerebral vein.
38. 2:07The first thing that we need to know is that the cerebral veins have no valves.
39. 2:11So unlike the veins of the systemic circulation; which are equipped with valves to prevent
40. 2:16backflow of blood, the cerebral veins have no valves.
41. 2:20Just like the dural sinuses.
42. 2:22Another thing is that the cerebral veins lie in the subarachnoid space.
43. 2:27So here we see a coronal section of the brain.
44. 2:30Here's the dural Sinus, or the superior sagittal Sinus which lies in the two spaces of dura
45. 2:36mater.
46. 2:37And here's the subarachnoid space, which contain cerebral veins as you see here,
47. 2:43draining into the dural sinuses.
48. 2:46And lastly; it's classified into; The Deep cerebral veins, and the Superficial
49. 2:51cerebral veins The deep cerebral veins drain blood from the
50. 2:55Deincephalon and the deep parts of the hemispheres; into the great cerebral vein, I'll show you
51. 3:00a scheme in a few seconds The superficial cerebral veins collect blood
52. 3:05from the cerebral cortex and drain blood into the venous sinuses.
53. 3:09Awesome.
54. 3:10Let's work from there, starting with the deep cerebral veins.
55. 3:13First on our list is the Great Cerebral Vein.
56. 3:16It's about 1 cm long.
57. 3:19It's unpaired.
58. 3:20And it opens into the straight Sinus.
59. 3:22Alright.
60. 3:23Then let's add the hypothalamus because this vein has tributary veins called Basal Veins
61. 3:28which run under the hypothalamus and drain the hypothalamus and the basal nuclei.
62. 3:33The Basal vein is formed at the anterior perforating substance at the region of the midbrain
63. 3:39and it's formed by the union of some small anterior cerebral veins that go together with
64. 3:44the anterior cerebral artery and supply the medial surface of the frontal lobe.
65. 3:51It has othe tributaries aswell like the deep middle cerebral vein and the inferior striatal
66. 3:58veins, but the most important one here in caps is the
67. 4:02Anterior cerebral vein.
68. 4:03Awesome.
69. 4:04Next let's build on this model and add the Thalami
70. 4:08The lateral ventricles, as well as the 3rd ventricle.
71. 4:11The next vein is the internal cerebral vein.
72. 4:15This one is located above the roof of the third ventricle,
73. 4:18And it collects blood from the basal ganglia, internal capsule, choroid plexus, and all
74. 4:23of the structures in this region.
75. 4:25And it does that mainly through three veins that drain into it.
76. 4:31Lateral to the lateral ventricle, we got caudate nucleus.
77. 4:35The first vein that drain into the internal cerebrla vein is the Superior Thalamostriatal
78. 4:41vein.
79. 4:42This vein curves anteriorly like this, and drains blood from
80. 4:46the thalamus, striatum, and internal capsule.
81. 4:50Next we have a vein that drains the choroid plexus of the lateral ventricles, called the
82. 4:55superior choroidal vein.
83. 4:57Then we have the anterior vein of septum pellucidum, which drain blood from
84. 5:01the septum pellucidum and head of the caudate nucleus.
85. 5:05Sweet.
86. 5:06That's all the deep cerebral veins that I wanted to cover.
87. 5:10Let's quickly recap those now before we talk about the superficial ones.
88. 5:14So here we see the superior sagittal sinus and the inferior sagittal Sinus.
89. 5:19Between them is the straight Sinus, which forms the confluence of sinuses
90. 5:23Then we got the occipital Sinus Transverse Sinus
91. 5:27Sigmoid Sinus, and the internal Jugular Vein.
92. 5:31We got the superior and the inferior petrosal sinuses which drain from the cavernous sinus.
93. 5:36We got the sphenoparietal sinus.
94. 5:38The intercavernous sinuses.
95. 5:40Then we have the basilar plexus, which drains several surrounding structures around it.
96. 5:45Here we have the hypothalamus, the lateral and the 3rd ventricles.
97. 5:50Right and the left Thalamus The caudate nuclei and the choroid plexus.
98. 5:54Here we have the great cerebral vein, which continues as the basal vein, and receives
99. 6:00blood from the anterior cerebral vein.
100. 6:03We have the Internal Cerebral vein, which receives blood from the
101. 6:07Superior thalamostriate vein, superior choroid vein and the anterior vein of septum pellucidum.
102. 6:14Awesome.
103. 6:15So that’s all the main veins that drain the inner gray matter and white mater of the
104. 6:20cerebral hemispheres.
105. 6:21Let’s now briefly talk about the superficial cerebral veins.
106. 6:25So again here we have the superior sagittal sinus
107. 6:29Occipital Sinus Transverse Sinus
108. 6:31Sigmoid and the Internl Jugular.
109. 6:34We have the Superior and the Inferior Petrosal Sinuses, and the cavernous sinus.
110. 6:38Cool.
111. 6:39So again the superficial cerebral veins drain blood from the cerebral cortex into these
112. 6:46sinuses we see here.
113. 6:47And there are 4 main ones that’s important to know here.
114. 6:51First one is the Superficial Middle Cerebral Vein.
115. 6:54It’s a vein that’s visible superficially when you look at the brain grossly.
116. 6:59begins close to the supramarginal gyrus, runs along the lateral cerebral sulcus as you see
117. 7:06here and drains into the sphenoparietal or cavernous
118. 7:11sinus in the front here.
119. 7:13And it mainly drains the lobes around it.
120. 7:16So the frontal lobe, parietal lobe and the temporal lobe.
121. 7:19Now there’re two important anestemoting branches here called the Superior anastomotic
122. 7:25vein of Trolard, which is a connection between the superficial middle cerebral vein
123. 7:29and superior cerebral veins of the superior sagittal sinus
124. 7:34And the Inferior anastomotic vein of Labbé, which is a connection between
125. 7:41the superficial middle cerebral vein and inferior cerebral veins of the transverse sinus
126. 7:48Then we have a lot of veins that collect blood from the superolateral surface of the cortex,
127. 7:54And drain them into mainly the superior sagittal sinus
128. 7:57Similarly, we have the inferior cerebral veins, which drain the inferior part of the cerebral
129. 8:04cortex, and empty the blood into the transverse, superior petrosal and the inferior petrosal
130. 8:10sinuses.
131. 8:11Next we have the superior and the inferior cerebellar veins, are also called infratentorial
132. 8:17veins Since they’re below the tentorium cerebelli.
133. 8:21So here we have the cerebellum, And these are the superior and the inferior
134. 8:27cerebellar veins.
135. 8:28So they drain blood from the cerebellum and flow into their closest sinus, which are the
136. 8:33superior and inferior petrosal sinuses, sigmoid sinus and the transverse sinus.
137. 8:39So that was all I had for the cerebral veins.
138. 8:43Awesome Let’s now talk briefly about the Diploic
139. 8:46Veins.
140. 8:47Diploic Veins like the the diploe, and drains them.
141. 8:51So remember from bone histology that diploe is the spongious bony tissue between the external
142. 8:59and the internal layers of the skull.
143. 9:01So here’s the skull Take one piece out, and it’ll look like
144. 9:05this.
145. 9:06The inner and outer surface are covered by Periosteum.
146. 9:10Just like the rest of the bones in our body.
147. 9:12The outer and inner part are compact bone And in here, you’ll find the spongy bone.
148. 9:18Which is also called Diploe.
149. 9:20Take a look at this model here.
150. 9:22Where do you think the Diploic Veins are?
151. 9:24They’re here!
152. 9:25I know you got this one right!
153. 9:27They’re some very small veins located inside the spongy part of the skull.
154. 9:33And they mainly drain the blood into our venous sinuses on the inside.
155. 9:37They can even communicate with the external veins of the skull also sometimes.
156. 9:42So that’s the Diploic Veins.
157. 9:44Next we have the Emissary veins!
158. 9:46The emissary veins are veins that connect the dural sinuses and the extracranial veins!
159. 9:52So in other words, they form cranio-cerebral anestemoses.
160. 9:56Here’s an extracranial vein.
161. 9:59Here’s the dural sinus.
162. 10:01Here are the foramina of the skull And inside these foramina, you’ll find the
163. 10:06emissary veins.
164. 10:07And don’t forget that we also have our diploic veins here.
165. 10:10Alright.
166. 10:11There are 4 main emissary veins.
167. 10:14So if we add the skull here.
168. 10:16Remember we had a superficial temporal vein?
169. 10:20The first emissary vein is called parietal emissary veins, whcih runs through the parietal
170. 10:25foramen connecting the superior sagittal sinus with the superficial temporal vein.
171. 10:31Then we have the occipital vein.
172. 10:33And the next emissary vein is called Mastoid Emissary vein, which runs through
173. 10:38the mastoid foramen connecting the sigmoid sinus with the occipital vein.
174. 10:43Then we have the Occipital Emissary Vein, which runs through the occipital foramen,
175. 10:48connecting the transverse sinus and the confluence of sinuses with the occipital vein.
176. 10:53Then we got the external vertebral venous plexus, which connects with the sigmoid sinus
177. 11:00through the condylar emissary veins.
178. 11:02So that was everything I had for the cerebral veins, diploic veins and the emissary veins.
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180. 11:10Whatever you find convenient to you.
181. 11:12See you next time