Blood Supply

Question 1

Epidural Hematoma

Answer 1

• Lens shaped (middle cranial fossa)
• Bleed in potential space b/w skull and dura
• @ Pterion
• Middle meningeal A.
• Momentary unconsciousness followed by lucidity (hours to days) then unconsciousness

Question 2

Subdural Hematoma

Answer 2

• Crescent shaped (jagged)
• Bleed b/w dura and arachnoid
• Cortical veins (as they open into sup. sagittal sinus)
• Slow accumulation of blood since its venous in nature

Question 3

Subarachnoid Hematoma

Answer 3

• Bright white areas on brain CT
• Aneurysm rupture
• Cerebral a. is source
• Massive bleed into CSF (thunderclap headache, deteriorating consciousness)

Question 4

Intracerebral (Subpial) Hematoma

Answer 4

• Large white spot of CT
• Bleeding within brain substance d/t stroke
• Middle cerebral a. usually
• D/t HTN or degenerative arterial disease

Question 5

Subfalcine Herniation

Answer 5

• AKA cingulate/falcine/falx herniation
• Supratentorial compartment (displaces brain tissue underneath falx cerebri)
• May compress ACA/frontal/parietal lobes
• May lead to transtentorial herniation

Question 6

Transtentorial Herniation

Answer 6

• AKA central herniation
• Brain displaced downward toward tentorial notch
• Comprises upper brainstem, CN III, lower structures (Basilar a. and PCA)
• Decerebrate/decorticate rigidity

Question 7

Uncal Herniation

Answer 7

• Uncus and parahippocampal gyrus extruded over tentorium cerebelli and through tentorial notch
• Impinge on midbrain

Question 8

Tonsillar Herniation

Answer 8

• Cerebellar tonsils through foramen magnum

- Compression of medulla and upper cervical spinal cord

Question 9

CN III relationships

Answer 9

b/w superior cerebellar a. and posterior cerebral a.

near posterior communicating a.

Question 10

CN IV relationships

Answer 10

b/w anterior inferior cerebellar a. and internal acoustic (labyrinth) a.

Question 11

CN II relationships

Answer 11

Internal carotid a. and anterior cerebral a. and anterior communicating a.

Question 12

CN V relationships

Answer 12

Aberrent vessel of superior cerebellar a. (Trigeminal neuralgia)

Question 13

CN VII relationships

Answer 13

Anterior inferior cerebellar a. (Bells)

Question 14

Anterior Cerebral A. supplies

Answer 14

Medial/Superior surfaces of frontal and parietal lobes

Question 15

Middle Cerebral A. supplies

Answer 15

Lateral surface of frontal and parietal lobes

Superior part of temporal lobe

Question 16

Posterior Cerebral A. supplies

Answer 16

Occipital lobe and inferior temporal lobe

Question 17

A1

Answer 17

Precommunicating segment

ICA to Anterior Communicating A.

Question 18

A2

Answer 18

Infracallosal segment

Ant. Communicating A. to where rostrum and genu of corpus callosum meet

Question 19

A3

Answer 19

Precallosal segement

Around genu of CC and ends where vessels turn caudal

Question 20

A4

Answer 20

Supracallosal

Superior to CC

Question 21

A5

Answer 21

Postcallosal

Caudal to CC

Question 22

M1

Answer 22

Sphenoidal/horizontal segment

ICA to bifurcation @ insula

Question 23

M2

Answer 23

Insular segment

bifurcation @ insula to circular sulcus of insula (right turn)

Question 24

M3

Answer 24

Opercular segment

Circular sulcus of insula to external surface of lateral fissure

Question 25

M4

Answer 25

Cortical segment | On the cortex

Question 26

P1

Answer 26

Basilar bifurcation to posterior communicating a.

Question 27

P2

Answer 27

Posterior communicating a. to around midbrain

Question 28

P3

Answer 28

Quadrigeminal segment | Within quadrigeminal cistern

Question 29

P4

Answer 29

Cortical segment

Question 30

Anterior Spinal A. supplies

Answer 30

``` Medial medulla (pyramids, hypoglossal nucleus, medial lemniscus) *Middle Medullary Syn ```

Question 31

Posterior spinal a. supplies

Answer 31

Lower medulla (FC, FG, CN, GN)

Question 32

Posterior inferior cerebellar a. supplies

Answer 32

Lateral medulla | *Lateral Medullary/Wallenberg

Question 33

Anterior inferior cerebellar a.

Answer 33

Cochlear nuclei (dorsal/ventral)

Question 34

Paramedian branches of basilar a.

Answer 34

Medial Pons | *Medial pontine syn

Question 35

Long circumferential branches of basilar a.

Answer 35

Lateral Pons | *Lateral pontine syn

Question 36

Anteromedial (paramedian) branches of basilar a. and P1

Answer 36

Medial midbrain | *Weber's syn

Question 37

Anterolateral (short circumferential) branches of quadrigeminal (P3) and superior cerebellar aa.

Answer 37

Inferior and Superior Colliculus

Question 38

Anterior Choroidal a.

Answer 38

Optic tract/hippocampal formation/internal capsule

Question 39

Lenticulostriate aa. of MCA

Answer 39

Internal Capsule