CHAPTER 17 - Book Review Questions Flashcards
The areas of the cerebral cortex listed below
receive their arterial supply as indicated:
(a) The precentral gyrus (face area) is supplied by
the middle cerebral artery.
(b) The postcentral gyros (face area) is supplied by
the anterior cerebral artery.
(c) The cuneus is supplied by the anterior cerebral
artery.
(d) The inferior temporal gyrus is supplied by the
middle cerebral artery.
(e) The Wernicke area is supplied by the posterior
cerebral artery.
A is correct.
- The precentral gyros (face area) is supplied by the middle cerebral artery (see Figs. 8-5 and 17-3). B. The face area of the postcentral gyros is supplied by the middle cerebral artery. C. The cuneus is supplied by the posterior cerebral artery (see Fig. 17-3). D. The inferior temporal gyros is supplied by the posterior cerebral artery (see Fig. 17-3). E. The Wernicke area is supplied by the middle cerebral artery.
The arteries listed below arise from the main stem
arteries as indicated:
(a) The ophthalmic artery is a branch of the middle
cerebral artery.
(b) The pontine arteries are branches of the internal carotid artery.
(c) The posterior communicating artery is a branch
of the middle cerebral artery.
(d) The posterior spinal artery arises from the vertebral artery.
(e) The posterior inferior cerebellar artery is a
branch of the basilar artery.
D is correct.
- The posterior spinal artery arises from the vertebral artery (see Fig. 17-7). A. The ophthalmic artery is a branch of the cerebral portion of the internal carotid artery. B. The pontine arteries are branches of the basilar artery (see Fig. 17-2). C. The posterior communicating artery is a branch of the internal carotid artery (see F1g. 17-2). E. The posterior inferior cerebellar artery is a branch of the vertebral artery (see Fig. 17-2).
The veins listed below drain into the venous sinuses indicated:
(a) The superior cerebral veins drain into the inferior sagittal sinus.
(b) The great cerebral vein drains into the superior sagittal sinus.
(c) The superior cerebellar veins drain only into the straight sinus.
(d) The spinal veins drain into the external vertebral venous plexus.
(e) The inferior sagittal sinus drains into the straight sinus.
E is correct.
- The inferior sagittal sinus drains into the straight sinus (see Fig. 17-5). A. The superior cerebral veins drain into the superior sagittal sinus (see Fig. 17-5). B. The great cerebral vein drains into the straight sinus (see Fig. 17-5). C. The superior cerebellar veins drain into the straight sinus, the transverse sinus, and the occipital sinus (see Fig. 17-5). D. The spinal veins drain into the internal vertebral venous plexus.
The following statements concern the cerebral blood flow:
(a) The sympathetic postganglionic fibers exert great control over the diameter of the cerebral blood vessels.
(b) It varies greatly with changes in the general blood pressure.
(c) Oxygen tension in the cerebral blood has no effect on the diameter of the cerebral blood vessels.
(d) One of the most powerful vasodilators of cerebral blood vessels is carbon dioxide.
(e) The blood flow for a particular area of nervous tissue following occlusion of a cerebral artery does not depend on the collateral circulation.
D is correct.
- One of the most powerful vasodilators of cerebral blood vessels is carbon dioxide. A. The sympathetic postganglionic fibers exert very little control over the diameter of the cerebral blood vessels. B. The cerebral blood flow varies only slightly with changes in the general blood pressure. C. Low oxygen tension in the cerebral blood causes vasodilation of the cerebral blood vessels. E. The blood flow for a particular area of nervous tissue following occlusion of a cerebral artery depends on the adequacy of the collateral circulation.
The following statements concern cerebral ischemia:
(a) Atheromatous degeneration of a cerebral artery does not cause degeneration of the nerve cells in the avascular area due to the presence of cerebrospinal fluid.
(b) Neuronal function ceases after the blood flow has stopped for about 10 seconds.
(c) Irreversible cerebral damage starts to occur after the blood flow has ceased for about 4 minutes.
(d) Shock occurring as the result of severe physical trauma does not result in cerebral ischemia.
(e) Cooling of the patient’s body following a cerebrovascular accident speeds up cerebral degeneration.
C is correct.
- Irreversible cerebral damage starts to occur after blood flow has ceased for about 4 minutes. A. Atheromatous degeneration of a cerebral artery may cause degeneration of the nerve cells in the avascular area and proliferation of the microglial cells in the surrounding area. B. Neuronal function ceases after blood flow has stopped for about 1 minute. D. Shock occurring as the result of severe physical trauma can result in cerebral lschemia. E. Cooling of the patient’s body following a cerebrovascular accident slows down cerebral degeneration.
The following statements concern the blood supply to the spinal cord:
(a) The posterior spinal arteries supply the posterior third of the spinal cord.
(b) The veins do not communicate with the veins of
the brain and the venous sinuses.
(c) The arteria radicularis magna (artery of Adamkiewicz) arises in the lower thoracic region
from the arch of the aorta.
(d) The anterior spinal artery is double but usually
arises from one vertebral artery.
(e) The spinal arteries are not reinforced by
branches of local arteries.
A is correct.
- The posterior spinal arteries supply the posterior third of the spinal cord (see p. 471). B. The spinal cord veins communicate with the veins of the brain and the venous sinuses. C. The arteria radicularis magna (artery of Adamkiewicz) arises from the aorta in the lower thoracic or upper lumbar vertebral levels. D. The anterior spinal artery is single but usually arises from both vertebral arteries. E. The spinal arteries are reinforced by radcular arteries, which are branches of local arteries.
A 58-year-old man, while eating his evening meal, suddenly complained of a severe headache. Moments later, he slumped forward and lost consciousness.
On being admitted to the hospital, the examining physician could have found the following physical signs except:
(a) He was in a deep coma, and his breathing was
deep and slow.
(b) The patient’s head was turned to the left.
(c) The right side of his face was flattened, and
saliva was drooling out of the right corner of
his mouth.
(d) The muscle tone of the limbs was less on the
right side than on the left.
(e) The right abdominal reflexes were absent, and
there was a positive Babinski response on the
left side.
E is the exception.
- A positive Babinski sign was present on the right side.
A 58-year-old man, while eating his evening meal, suddenly complained of a severe headache. Moments later, he slumped forward and lost consciousness.
Three days later, the patient regained consciousness, and the following additional signs could have become apparent except:
(a) The right arm and, to a lesser extent, the right
leg were paralyzed.
(b) Movements of the left arm and leg and the left
side of the face were normal.
(c) The upper and lower parts of the right side of
his face were paralyzed.
(d) The patient had difficulty in swallowing.
(e) The patient was unable to speak.
C is the exception.
- The muscles of the upper part of the face on the right side are not affected by a lesion involving the upper motor neurons on the left side of the brain. This is due to the fact that the part of the facial nucleus of the seventh cranial nerve that controls the muscles of the upper part of the face receives corticonuclear fibers from both cerebral hemispheres.
A 58-year-old man, while eating his evening meal, suddenly complained of a severe headache. Moments later, he slumped forward and lost consciousness.
During the next 2 weeks, the following signs could have developed except:
(a) The muscles of the limbs on the right side
became hypertonic.
(b) The tendon reflexes on the right side became
hyperactive.
(c) The patient had some sensory loss on the right
side.
(d) The patient was suffering from urinary incontinence.
(e) The muscles on the left side exhibited hypotonia.
E is the exception.
- The cerebral lesion was on the left side of the brain, and the muscles of the left leg were completely unaffected by the vascular accident.
A 58-year-old man, while eating his evening meal, suddenly complained of a severe headache. Moments later, he slumped forward and lost consciousness.
The neurologist incharge of this patient interpreted
the findings as follows. All his interpretations were likely to be correct except:
(a) The sudden onset of a severe headache followed by loss of consciousness is a common finding in patients with a blockage of a cerebral artery.
(b) The depth of coma is unrelated to the extent of the arterial blockage.
(c) Paralysis of the face on the right side indicated the presence of a lesion on the left side of the brain.
(d) The patient’s head and eyes were turned to the left (i.e., to the side of the lesion).
(e) The loss of right-sided abdominal reflexes indicated the presence of a lesion on the left side of the brain.
B is the exception.
- The depth of coma is related to the extent of the arterial blockage.
A 58-year-old man, while eating his evening meal, suddenly complained of a severe headache. Moments later, he slumped forward and lost consciousness.
The following physical signs and known anatomical data strongly suggested the involvement of the left middle cerebral artery except:
(a) Paralysis of the right side of the face and the right arm was more severe than that of the right leg.
(b) The presence of aphasia.
(c) The central branches of the middle cerebral
artery do not supply the lentiform nucleus, the
caudate nucleus, and the internal capsule.
(d) The left middle cerebral artery supplies the entire lateral surface of the cerebral hemisphere except for the narrow strip supplied by
the anterior cerebral artery.
(e) The left posterior cerebral artery supplies the
occipital pole and the inferolateral surface of the cerebral hemisphere.
C is the exception.
- The central branches of the right middle cerebral artery do supply the right lentiform and caudate nuclei and the right internal capsule.
A 60-year-old man was admitted to the emergency department, complaining of the sudden onset of excruciating, sharp, tearing pain localized to the back of the chest and the back. After a thorough physical and radiologic examination, a diagnosis of dissection of the descending thoracic aorta was made. Within a few hours, the patient started to experience “girdle” pain involving the fourth thoracic dermatome on both sides. Later, he was found to have bilateral thermoanesthesia and analgesia below the level of the fourth thoracic dermatome. Position sense, vibration, and light touch remained normal. Complete spastic paralysis of both legs quickly developed.
The sudden onset of “girdle” pain in this patient was most likely caused by:
(a) Pressure on the fourth thoracic spinal nerves
(b) Blockage of the origins of the posterior intercostal arteries that give rise to the segmental
spinal arteries by the aortic dissection
(c) Discomfort caused by the expanding aneurysm
(d) Osteoarthritis of the vertebral column
B is correct.
- In the thoracic region, the posterior intercostal arteries arise directly from the thoracic aorta and can be blocked by a blood clot as the aortic dissection progresses. The segmental spinal arteries, which are branches of the posterior intercostal arteries, give origin to the radicular arteries that supply the spinal nerves and their roots. If these arteries are compromised, severe pain is experienced in the distribution of the spinal nerves involved and, hence, the “girdle” pain.
A 60-year-old man was admitted to the emergency department, complaining of the sudden onset of excruciating, sharp, tearing pain localized to the back of the chest and the back. After a thorough physical and radiologic examination, a diagnosis of dissection of the descending thoracic aorta was made. Within a few hours, the patient started to experience “girdle” pain involving the fourth thoracic dermatome on both sides. Later, he was found to have bilateral thermoanesthesia and analgesia below the level of the fourth thoracic dermatome. Position sense, vibration, and light touch remained normal. Complete spastic paralysis of both legs quickly developed.
The development of bilateral thermoanesthesia and analgesia below the level of the fourth thoracic segment of the cord and the later development of paraplegia could be camed by:
(a) Absent circulation in the posterior spinal arteries
(b) Cerebral hemorrhage
(c) Absent circulation in the anterior spinal artery
(d) Collapse of the fourth thoracic vertebral body
C is correct.
- The blood supply to the spinal cord is meager and if the segmental arteries that reinforce the anterior and posterior spinal arteries are compromised, ischemia of the spinal cord could follow. In this patient, the circulation in the anterior spinal artery ceased and the blood supply to the anterior two-thirds of the spinal cord was cut off. This would explain the sudden development of bilateral thermoanesthesia and analgesia (spinothalamic tracts in both lateral white columns) and the paraplegia (corticospinal tracts in both lateral white columns). The sparing of the sensations of position, vibration, and light touch, which travel in the fasciculus gracilis and fasciculus cuneatus, can be explained by the fact that the posterior white columns are supplied by the posterior spinal arteries in which the circulation is adequate.
The following statements concern the blood supply to the brain:
(a) The brain receives its blood supply directly
from the two external carotid arteries.
(b) The circle of Willis is formed by the anterior cerebral, the internal carotid, the posterior cerebral, the basilar, and the anterior and posterior communicating arteries.
(c) The cerebral arteries do not anastomose on the
surface of the brain.
(d) Numerous anastomoses occur between the
branches of the cerebral arteries once they
have entered the substance of the brain.
(e) The main blood supply to the internal capsule is from the central branches of the anterior
cerebral artery.
B is correct.
- The circle of Willis is formed by the anterior cerebral, the internal carotid, the posterior cerebral, the basilar, and the anterior and posterior communicating arteries (see Fig. 17-0). A. The brain receives its blood supply directly and indirectly from the two internal carotid and the two vertebral arteries that lie within the subarachnoid space. C. The cerebral arteries anastomose on the surface of the brain. D. No anastomoses exist between the branches of the cerebral arteries once they have entered the substance of the brain. E. The main blood supply to the internal capsule is from the central branches of the middle cerebral artery.
