Lecture 3: Head and Neck Vasculature I: Sinuses and Veins

Question 1

Most of the CSF is produced by the ________ of the _______.

Answer 1

Most of the CSF is produced by the choroid plexuses of the lateral, third, and fourth ventricles

Question 2

CSF is resorbed in the ______.

Answer 2

Arachnoid villi

Question 3

Atrophy of the cerebral cortex may result in ______.

Answer 3

External Hydrocephalus

Question 4

Occlusion of the cerebral aqueduct would result in _______ of the ______ and _________

Answer 4

Occlusion of the cerebral aqueduct would result in hydrocephalus of the 3rd and lateral ventricles

Question 5

Occlusion of the right interventricular foramen would result in _____ of the _______.

Answer 5

Occlusion of the right interventricular foramen would result in Hydrocephalus of the Lateral Ventricle

Question 6

Obstruction of the subarachnoid space at the level of the tentorial notch may result in _________.

Answer 6

Communicating Hydrocephalus

Question 7

CSF enters the subarachnoid space via the ________ and ________.

Answer 7

Medial and Lateral Foramina

Question 8

Secondary to a subarachnoid hemorrhage blood in the CSF may occlude the _______ and result in _________.

Answer 8

Secondary to a subarachnoid hemorrhage blood in the CSF may occlude the Arachnoid villi and result in secondary (chemical) Meningitis.

Question 9

Retromandibular vein is formed by which 2 veins?

Answer 9

Superficial Temporal V. + Maxillary V.

Question 10

Where is the Pterygoid plexus of veins and what does it drain into?

Answer 10

• Extensive venous network located on lateral surface of the medial pterygoid muscle and surrounding lateral pterygoid muscle
• Drains into: deep facial, maxillary, and retromandibular veins

Question 11

What are the main differences between the superior bulb versus inferior bulb of the IJV; where is each located?

Answer 11

• Superior bulb is in the jugular fossa and does not have a valve
• Inferior bulb is posterior to the interval between sternoclavicular heads of the SCM, and has a valve

Question 12

What are the Pericervical lymph nodes and where do they drain?

Answer 12

• Form a “collar” of superficial LN’s around the base of head
• Include the: occipital, mastoid, parotid, submandibular, buccal, and submental group
• Drain directly into the: deep cervical LN’s

Question 13

What are the Superficial Cervical LN’s; where are they found; where do they drain?

Answer 13

• Two groups
• Posterior Superficial Cervical LN’s adjacent to the external jugular vein in the posterior (lateral) triangle
• Anterior Superficial Cervical LN’s adjacent to the anterior jugular vein in the anterior triangle
• Both groups drain into the: deep cervical LN’s

Question 14

Where are the Deep Cervical LN’s located; which 2 are most important; which group is related to the tonsils?

Answer 14

• Located along the length of the IJV
• Jugulo-digastric nodes = tonsillar

- Jugulo-omohyoid nodes

Question 15

Where is the Thoracic duct located; where does it receive lymph from?

Answer 15

• Runs in front of the anterior scalene and behind the left carotid sheath
• Is located only on the left side of the root of the neck
• Receives lymph from the left side of the head, and all of the body except the RUE and head

Question 16

Where is the lateral ventricle and what forms its borders?

Answer 16

• C-shaped, arc-shaped cavity in core of each cerebrum (right and left)
• Corpus callosum forms the lateral walls, and the caudate nucleus in on its floor

Question 17

What is the interventricular foramen of Monroe and why is it clinically significant?

Answer 17

• Connects the lateral ventricles to the third ventricle
• One of both foramina may be obstructed by tumors such as a choroid plexus ependymomas in the third ventricle

Question 18

The thoracic fuct drains into the __________.

Answer 18

IJV/subclavian vein junction

Question 19

The retromandibular vein has a direct relationship with the ______nerve.

Answer 19

Facial

Question 20

The distal branches of the inferior thyroid artery have a direct relationship with the _______ nerve.

Answer 20

Recurrent laryngeal nerve

Question 21

The _______ is embedded in the prevertebral fascia just posterior to the common carotid artery.

Answer 21

Cervical sympathetic chain

Question 22

Where is the third ventricle and what is it connected to?

Answer 22

• Thin vertical chamber in the midline between the thalami
• Continous with the lateral ventricles via the interventricular foramina
• Continous with the fourth ventricle via the cerebral aqueduct

Question 23

A midbrain tumor such as astrocytomas may obstruct the cerebral aqueduct and lead to?

Answer 23

Hypertrophy of the lateral and third ventricles (supratentorial internal hydrocephalus)

Question 24

What is the central canal of the brain?

Answer 24

A cul-de-sac extending from the obex of the fourth ventricle to C5-8

Question 25

Pathologically, the central canal may enlarge and develop a cavity (syrinx) in the center of the cord (myelia), what is this condition called and what do patients complain of?

Answer 25

- Syringomyelia - Complain of bilateral anesthesia of the shoulders and upper limbs

Question 26

The fourth ventricle is shaped like a four-sided pyramid and what are each of its sides continous with?

Answer 26

- The third ventricle via the cerebral aqueduct - Cerebellomedullary cistern via the medial and lateral foramina - Blind-ending central canal at the obex, which becomes central canal of spinal cord

Question 27

The brain is floating in the CSF-filled _________ space, which is bounded by ______ and ________ mater

Answer 27

The brain is floating in the CSF-filled **subarachnoid space**, which is bounded by **pia mater** and **arachnoid**

Question 28

What is the cerebellomedullary cistern (*cisterna magna)?*

Answer 28

Large CSF-filled space just above the foramen magnum and posteior to the medulla

Question 29

How many mL of CSF in ventricles, in the entire system, and produced each day?

Answer 29

- **20-25 mL** in the **ventricles** - **140 mL** in the **system** - **600-700 mL** produced each day

Question 30

What is the Hydrocephaly?

Answer 30

Increase in cerebral mass and/or size due to **presence of an excessive amount of CSF in the ventricular system, the subarachnoid space, or both**

Question 31

External Hydrocephalus is an excessive accumulation of CSF where; what are the 2 types?

Answer 31

- In the **subarachnoid space** 1) **Supratentorial** is most commonly associated with senile atrophy of the cortex, i.e., Alzheimer's disease 2) **Infratentorial** is seen in combination with **communicating hydrocephalus**

Question 32

What is Internal Hydrocephalus often called, why?

Answer 32

- Noncommunicating hydrocephalus, because it: - Does not drain into the subarachnoid space

Question 33

Internal Hydrocephalus may be caused by obstruction of what 3 strucutres?

Answer 33

1) Interventricular foramen (third ventricle choroid plexus ependymoma) 2) Cerebral aqueduct (midbrain astrocytoma) 3) Medial and lateral foramina (Arnold Chiari malformation, Dandy Walker Cyst)

Question 34

The superior sagittal sinus usually empties into the \_\_\_\_\_\_.

Answer 34

Right transverse venous sinus

Question 35

The sigmoid sinus empties into the _______ at the \_\_\_\_\_\_\_\_.

Answer 35

The sigmoid sinus empties into the **IJV** at the **Jugular foramen**

Question 36

The superior opthalmic vein empties into the \_\_\_\_\_\_\_\_.

Answer 36

The superior opthalmic vein empties into the **Cavernous Sinus**

Question 37

The veins of the spinal cord collectively drain into what, which is located in what space?

Answer 37

- Drain into the **internal venous plexus of Batson** - Located in the **epidural space**

Question 38

What 2 major veins of the cerebral hemisphere drain into the Great Vein of Galen?

Answer 38

1) Internal Cerebral Vein 2) Basal Vein of Rosenthal

Question 39

What vein drains most of the deep cerebrum and what can obstruction of this vein lead to?

Answer 39

- The great vein of Galen - Obstruction of this vein is usually **fatal** - May also become dilated and form a venous varix; a **great vein varix** may compress the **pineal body** and **posterior commissure**

Question 40

The superior sagittal sinus drains most of what part of the brain and drains into which vein?

Answer 40

Drains **most of the cerebral cortex** and empties into the **right transverse sinus**

Question 41

Where is the straight sinus formed, what major vein drains into it, and what does the straight sinus drain into?

Answer 41

- Formed at the **intersection** of the **falx** and the **tentorium** - **The great cerebral vein of Galen** drains vital deep structures of the cerebrum and empties into the straight sinus - Straight sinus drains into the **left transverse sinus**

Question 42

The confluens receives venous drainage from what sinuses?

Answer 42

Superior sagittal, straight, and occipital sinuses

Question 43

In 2/3's of the cases the superior sagittal sinus empties directly into the ________ sinus, and the straight sinus drains directly into the __________ sinus.

Answer 43

- Supeior sagittal sinus empties directly into the **right transverse sinus** - Straight sinus drains directly into the **left transverse sinus**

Question 44

Thrombosis of the straight venous sinus or left transverse venous sinus results in?

Answer 44

Ischemia and/or necrosis of structures in the **deep cerebrum.** This is usually **fatal**

Question 45

What is a falx herniation?

Answer 45

- Falx cerebri only partially separates the cerebral hemispheres, so unilateral space-occupying lesions of the cerebrum may cause the cingulate gyrus to herniate across the **midline** beneath the free edge of the falx - **Midline shift**

Question 46

What is a Tentorial or Uncal Herniation?

Answer 46

- Profuse, high-pressured bleeding rapidly expands the epidural space, thereby pressing upon adjacent cerebral hemisphere and herniating the cerbrum under the falx cerebri (**falx herniation**) and/or through the **tentorial notch (tentorial or uncal herniation)** - Compresses and displaces the midbrain - Bilateral compression of the midbrain reticular formation results in progressive decrease in the level of conciousness

Question 47

What is Tonsilar Herniation?

Answer 47

- Space expanding or occupying masses in the posterior cranial fossa may cause the cerebellar tonsil to herniate through the foramen magnum, which can compress the lower medulla/upper cervical spinal cord. - Seen in **Arnold-Chirari Malformation**

Question 48

A fracture of the pterion may rupture which artery and lead to?

Answer 48

- Middle meningeal artery - Epidural hematoma - Profuse high-ressure bleeding rapidly expans the **epidural space,** and may cause a midline shift of cerebral hemispheres (**falx herniation**) and/or an **uncal herniation**

Question 49

Increased intracranial pressure applies a cuff-like pressure to the small veins on the optic nerve via of the adjacent subarachnoid extension; what can this lead to?

Answer 49

Decreased venous drainage from the retina results in **edema of the retina** and swelling of the optic disc (**papilledema**)

Question 50

Thrombosis of the posterior portion of the superior venous sinus or right transverse venous sinus results in?

Answer 50

**Cortical** ischemia and/or necrosis

Question 51

All of the major blood vessesl supplying the CNS pass through or course in the subarachnoid space, rupture of one of these vessesl in this space is called; clinically how can you determine this?

Answer 51

- Subarachnoid Hemorrhage - Indicated by the presence of **erythrocytes** in the **CSF** - CSF is usually sampled by inserting a needle into either the cerebellomedullary or lumbar cisterns

Question 52

Trauma to which veins may lead to rupture and a Subdural Hematoma?

Answer 52

- Cerebral (bridging) veins - May rupture as they cross the **subdural** space - Same signs and symptoms as epidural hematomas, but their **onset may be delayed for days or weeks**