Chapter 3 : Blood Supply of The Central System (3)

Question 1

1. A 50-year-old hypertensive woman com¬plains of numbness and weakness in her left leg and foot. Occlusion of which of the follow-ing vessels may account for this complaint? (A) Anterior choroidal artery (B) Anterior cerebral artery (C) Interior carotid artery (D) Middle cerebral artery (E) Posterior artery

Answer 1

I-B. The anterior cerebral artery perfuses the paracentral lobule, which represents the motor and sensory strips of the leg and foot areas

Question 2

2. A 15-year-old boy is hit on the temple with a baseball and becomes unconscious. After about 10 minutes, he regains consciousness, but he soon becomes lethargic, and over the next 2 hours, he becomes stuporous. HIS pupils are unequal. Intracranial hemorrhage is suspected. Which of the following vessels is most likely to be the source of the hemorrhage? (A) Anterior cerebral artery (B) Anterior communicating artery (C) Basilar artery (D) Middle cerebral artery (E) Middle meningeal artery

Answer 2

2-E. Laceration of the middle meningeal artery gives rise to an epidural hematoma. Classic signs’ of an epidural hematoma are skull trauma, usually with fracture, and sequential progression from unconsciousness to lucidity to progressive coma to death dLle to trans tentorial herniation with ipsilateral third palsy.

Question 3

3. The optic chiasm is supplied by all ofthe following arteries EXCEPT the (A) internal carotid artery (B) anterior communicating artery (C) anterior choroidal artery (D) posterior communicating artery (E) anterior cerebral artery

Answer 3

3-C. The anterior choroidal artery lies outside of the circle of Willis and does not supply the optic chiasm.

Question 4

4. All of the following statements concerning the internal carotid artery are correct EXCEPT: (A) it enters the skull via the sphenoid bone (B) it lies within the cavernous sinus (C) it gives off direct branches to the internal capsule (D) it gives rise to the anterior choroidal artery (E) it gives rise to the posterior communicat¬ing artery

Answer 4

4-A. The internal carotid artery enters the skull via the carotid canal of the temporal bone.

Question 5

5. The cavernous sinus and its lateral wall contain all of the following structures EXCEPT the (A) carotid siphon (B) oculomotor, abducent, and trochlear nerves (C) ophthalmic and maxillary nerves (D) optic nerve (E) postganglionic sympathetic fibers

Answer 5

5-D. The cavernous sinus and its lateral wall contain the carotid siphon; the oculomotor (CN II!), abducent (CN VI), and trochlear nerves (CN IV); a sympathetic plexus; and the ophthalmic and maxillary divisions of the trigeminal nerve (CN V). The optic nerve (CN II) and ophthalmic artery reach the orbit via the optic canal.

Question 6

6. All of the following statements concerning the middle meningeal artery are correct EXCEPT . (A) it is usually a branch of the maxillary artery (B) it enters the cranium through the foramen spinosum (C) laceration results in epidural hemorrhage (D) it supplies most of the dura of the calvarium (E) it supplies the dura of the posterior cra¬nial fossa

Answer 6

6-E. The middle meningeal artery usually is a branch of the maxillary artery, which enters the cranium via the foramen spinosum and supplies most of the dura of the calvarium. Laceration of this artery leads to epidural hemorrhage (hematoma). The artery and its accompanying dural veins lie between the periosteal and meningeal layers of the dura. The dura of the posterior fossa is supplied by branches of the ascending pharyngeal, vertebral, and occipital arteries (posterior meningeal arteries).

Question 7

Questions 7-11 The response options for items 7-11 are the same. You will be required to select one answer for each item in the set. (A) Posterior cerebral artery (B) Superior cerebellar artery (C) Anterior inferior cerebellar artery (D) Posterior inferior cerebellar artery (E) Anterior spinal artery 7. Usually gives rise to the artery that suplies the inner ear

Answer 7

7-C. The anterior inferior cerebellar artery usually gives rise to the labyrinthine artery, which supplies the structures of the inner ear (i.e., the cochlea and vestibular apparatus).

Question 8

Questions 7-11 The response options for items 7-11 are the same. You will be required to select one answer for each item in the set. (A) Posterior cerebral artery (B) Superior cerebellar artery (C) Anterior inferior cerebellar artery (D) Posterior inferior cerebellar artery (E) Anterior spinal artery 8.Supplies the facial nucleus and the spinal trigeminal nucleus and tract

Answer 8

8-C. The facial nucleus and the spinal trigeminal nucleus and tract are supplied by the anterior inferior cerebellar artery.

Question 9

Questions 7-11 The response options for items 7-11 are the same. You will be required to select one answer for each item in the set. (A) Posterior cerebral artery (B) Superior cerebellar artery (C) Anterior inferior cerebellar artery (D) Posterior inferior cerebellar artery (E) Anterior spinal artery 9. Is the terminal branch of the basilar artery

Answer 9

9-A. The posterior cerebral artery is the terminal branch of the basilar artery.

Question 10

Questions 7-11 The response options for items 7-11 are the same. You will be required to select one answer for each item in the set. (A) Posterior cerebral artery (B) Superior cerebellar artery (C) Anterior inferior cerebellar artery (D) Posterior inferior cerebellar artery (E) Anterior spinal artery 10. Supplies the deep cerebellar nuclei

Answer 10

10. B. The superior cerebellar artery supplies the superior surface of the cerebellum and the cerebellar nuclei (dentate nucleus).

Question 11

Questions 7-11 The response options for items 7-11 are the same. You will be required to select one answer for each item in the set. (A) Posterior cerebral artery (B) Superior cerebellar artery (C) Anterior inferior cerebellar artery (D) Posterior inferior cerebellar artery (E) Anterior spinal artery 11. Supplies the nucleus ambiguus

Answer 11

ll. D. The posterior inferior cerebellar artery supplies the dorsolateral medullary fiel4t including the nucleus ambiguus.

Question 12

Questions 12-16
Match the statements in items 12-16 with the appropriate lettered artery shown inthe figure.

12. An aneurysm of this artery may cause a third nerve palsy

Answer 12

12-E. An aneurysm of the posterior communicating artery may cause a third nerve palsy.

Question 13

Questions 12-16
Match the statements in items 12-16 with the appropriate lettered artery shown inthe figure.

13. Irrigates the posterior limb ofthe internal capsule

Answer 13

13-D. The anterior choroidal artery irrigates the posterior limb of the internal capsule.

Question 14

Questions 12-16
Match the statements in items 12-16 with the appropriate lettered artery shown inthe figure

14. Occlusion of this artery results in a fluent receptive aphasia

Answer 14

14-C. Occlusion of the proximal stem ofthe left middle cerebral artery results in Wernicke aphasia,a fluent receptive aphasia.

Question 15

Questions 12-16
Match the statements in items 12-16 with the appropriate lettered artery shown inthe figure.

15. An aneurysm of this artery may result in Horner syndrome

Answer 15

15-B. An aneurysm of the internal carotid artery within the cavernous sinus can interrupt postganglionic sY.IDllathetic fiber resulting in Horner syndrome.

Question 16

Questions 12-16
Match the statements in items 12-16 with the appropriate lettered artery shown inthe figure.

16. Occlusion of this artery results in infarc¬tion of the paracentral lobule with Babinski sign

Answer 16

16-A. The anterior cerebral artery perfuses the mesial aspect of the hemisphere from the frontal pole to the parieto-occipital suleus, including the paracentral lobule. The paracentral lobule gives rise to corticospinal fibers to the contralateral foot and leg. Destruction of these fibers results in the Babinski sign.

Question 17

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.

17. Thrombosis may result in an abducent palsy

Answer 17

17-A. Cavernous sinus thrombosis may result in cranial nerve palsies. including CN III, CN IV, CN VI, CN V·I, and CN V-2.

Question 18

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.
18. Drains the deep cerebral veins

Answer 18

I8-E. The great cerebral vein of Galen drains the deep cerebral veins that drain the thalamusand basal ganglia. ‘!’hu vein of Galcll c.lI11pt.ics into the straight sinus.

Question 19

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.

19. Marks the site of the foramen of Monro

Answer 19

19-B. The venous angle marks the site of the interventricular foramen of Monro; it is the point where the septal and thalamostriate veins meet.

Question 20

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.

20. Receives the arachnoid granulations

Answer 20

20-C. The superior sagittal sinus receives cerebrospinal fluid (CSF) via the arachnoid granulations.

Question 21

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.

21. Receives blood from the ophthalmic veins
    

Answer 21

21-A. The inferior and superior ophthalmic veins drain into the cavernous sinus.

Question 22

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.

22. Laceration results in subdural hemorrhage

Answer 22

22-D. Laceration of the superior cerebral veins (bridging veins) results in subdural hemorrhage (hematoma).

Question 23

Questions 17-23 Match the statements in items 17-23 with the appropriate lettered artery shown in the figure.

23. Receives blood from the straight, sagittal, superior, and transverse sinuses

Answer 23

23-F. The confluence of the sinuses (torcular Herophili) receives blood from the straight, sagittal, superior, and transverse sinuses.