Chapter 1 Osteo1ogy.............................1 Chapter 2



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d. Extensor toe response (Babinski's sign)

e. Clonus

-is a repetitive, sustained MSR (e. g. , ankle clonus).

8. Lower motor neuron (LMN) lesions

-result from damage to motor neurons or their peripheral axons.

-result in:

(1) Flaccid paralysis

(2) Arefiexia

(3) Muscle atrophy

(4) Fasciculations and fibrillations

9. The proprioceptive pathway for trunk and limbs carries highly localized deep sensations (body posture, movement, vibration and pressure as well as two-point discrimination) from receptors to the cortex. The axons, with their first-order neurons in the spinal ganglia, reach the CNS through the posterior roots of spinal nerves and collect sensory information from different body areas. Axons from the spinal ganglia ipsilaterally ascend within the fasciculus gracilis or fasciculus cuneatus in the spinal cord. The fasciculus gracilis transmits deep sensations from the lower half of the body (below the fifth thoracic segment). Fasciculus cuneatus fibers carry deep sensations from the upper body and enter the spinal cord above the level of fourth thoracic segment. These fibers ipsilaterally ascend in the posterior funiculus of spinal cord toward the brainstem and terminate at the gracile nucleus and cuneatus nucleus, the second-order neurons. The internal arcuate fibers, the second order fibers from the nuclei gracilis and cuneatus, travel anteromedially and cross the midline just above the pyramid in the medulla. After crossing, the internal arcuate fibers form the medial lemniscus. The medial lemniscus ascends along the midline and posterior to pyramidal tract through the medulla oblongata. The medial lemniscus is horizontally arranged in the pontine tegmentum. Then it posterolaterally migrates in the midbrain to enter the ventral posterolateral nucleus of the dorsal thalamus, the third-order neurons. The axons carrying the information from the thalamus to the sensory cortex through the anterior posterior limb of the internal capsule are collectively known as projection fibers, central thalamic radiations. They terminate in the upper two-thirds of the postcentral gyrus, the primary somesthetic area in the parietal lobe.

10. What effects would lesion in the optic nerve have on monocular blindness in the eye? A chiasmatic lesion (often owing to a pituitary tumor or a lesion around the sella turcica) can injure the decussating axons of retinal ganglion cells within the optic chiasm. These axons originate in the nasal halves of the two retinas. Thus, this type of lesion produces bitemporal hemianopsia, characterized by blindness in the lateral or temporal half of the visual field for each eye. A pathology encroaching on the lateral edge of the optic chiasm selectively interrupts the fibers from the ipsilateral temporal portion of the retina, resulting in nasal hemianopsia in the corresponding eye. Lesions behind the optic chiasm cause a field defect in the temporal field of one eye, together with a field defect in the nasal (medial) field of the other eye. The result is a homonymous hemianopsia in which the visual field defect is on the side opposite the lesion.

11. The light stimulus acting upon the retinal photoreceptors gives rise to activity in retinal ganglion cells, the axons of which form the optic nerve. Activity is conducted through the optic chiasma and along the optic tract, and the majority of fibers end in the lateral geniculate nucleus of the thalamus. However, a small number of fibers leave the optic tract before it reaches the thalamus and synapse in the pretectal area by short neurons which synapse bilaterally with preganglionic parasympathetic neurons in the accessory nucleus of oculomotor nerve (Edinger-Westphal's nucleus) complex in the rostal midbrain. Efferent impulses pass along parasympathetic fibers of the oculomotor nerve to the orbit where they synapse in the ciliary ganglion. Postganglionic fibers (short ciliary nerve) pass to the eyeball to supply sphincter pupillae, which reduces the size of the pupil when it contracts. So light shone on the retina of one eye causes both pupils to constrict normally. The response in the eye stimulated is called the direct papillary light reflex,, while that in the opposite eye is known as the indirect (or consensual) papillary light reflex.

12. The corticospinal tract originates the pyramidal cells of the superior and middle parts of the precentral gyrus and anterior part of the paracentral lobule. It travels through the posterior limb of internal capsule of the telencephalon, and then descends through the intermediate 3/5 of the cerebral peduncles of the midbrain. Later it runs through the basilar part of the pons and continues to the pyramids in the medulla oblongata. About 75% to 90% of the corticospinal tract crosses pyramidal decussation at the caudal end of the medulla oblongata. After crossing, these fibers descend into the lateral corticospinal tract in the lateral funiculus of the spinal cord. These fibers terminate on the interneuron and lower motor neurons in the ipsilateral anterior gray horns of the spinal cord, and mainly control musculature of the limbs. About 10% to 15 % of the corticospinal tract does not cross in the pyramidal decussation but descends in the anterior funiculus of the spinal cord (the anterior corticospinal tract). These fibers cross or uncross above the level of mid-thoracic segments, close to the anterior horns of spinal cord, and control the skeletal muscles of trunk. Up to 3% of the decending fibers in the lateral corticospinal tract are uncrossed. The ipsilateral decending projections mainly control musculature of trunk. Some axons of upper motor neurons (the pyramidal cells in the inferior part of the precentral gyrus) that conduct impulses for the control of skeletal muscles in the head extend through the genu of the internal capsule to the midbrain, where they join the corticobulbar tracts in the right and left of cerebral peduncles. Some of the axons in the corticobulbar tracts decussated at the midplane in the brainstem, whereas others have not. The axons terminate the bilateral motor nuclei of the cranial nerves (nucleus of oculomotor nerve, nucleus of trochlear nerve, motor nucleus of trigeminal nerve, nucleus ambiguus, accessory nucleus, superior part of the facial nucleus), and the contralateral hypoglossal nucleus and the inferior part of the facial nucleus.

(Li Feng, Ding Wenlong)

Multiple Choice Questions

A1

1. An obstruction in the interventricular foramen would interfere with the flow of cerebrospinal fluid into the .



A. lateral ventricle

B. third ventricle

C. fourth ventricle

D. subarachnoid space of the spinal cord

E. central canal of the spinal cord

2. The cerebral aqueduct links the .

A. lateral ventricles

B. lateral ventricles and 3rd ventricle

C. 3rd and 4th ventricles

D. lateral ventricles and 4th ventricle

E. 3rcl ventricle and central canal of the spinal cord

3. Which is not associated with cerebrospinal fluid?

A. cerebral aqueduct

B. lateral ventricle

C. choroid plexus

D. subarachnoid space

E. epidural space

4. The region around the spinal cord that contains cerebrospinal fluid is the .

A. central canal

B. subarachnoid space

C. epidural space

D. 4th ventricle

E. 3rd ventricle

5. Which of the following is true statement relating to the meninges?

A. The dura mater is composed of a dense fibrous connective tissue.

B. The dura mater around the brain is single-layered

C. Venous sinuses occur between the two dural layers around the spinal cord.

D. The most superficial meninx is the arachnoid membrane.

E. The epidural space contains cerebrospinal fluid.

6. Which of the following arteries is not included in the circle of Willis?

A. the anterior communicating artery

B. the anterior cerebral artery

C. the middle cerebral artery

D. the posterior communicating artery

E. the posterior cerebral artery

7. Regarding the meninges, which of the following is false?

A. The dura mater is sensitive to pain.

B. Rupture of an aneurysm of a cerebral artery leads to subarachnoid hemorrhage.

C. A torn middle meningeal artery bleeds into the space between the endosteal dura and the bones of the cranium.

D. The cerebellomedullary cistern is a subarachnoid space between the medulla and the cerebellum.

E. The diaphragma (tentorium) sellae is a double layer of arachnoid mater.

8. The meninges, from the outermost to the innermost, are .

A. the dura mater, the pia mater, the arachnoid

B. the pia mater, the dura mater, the arachnoid

C. the arachnoid, the pia mater, the dura mater

D. the dura mater, the arachnoid, the pia mater

E. the pia mater, the arachnoid, the dura mater

9. Lumbar punctures are performed into the space in order to remove cerebrospinal fluid.

A. subdural

B. subarachnoid

C. ventricles

D. epidural

E. central canal

10. The cerebrospinal fluid is secreted by in the ventricles.

A. arachnoid granulations

B. choroid plexus

C. pia mater

D. arteries

E. veins

11. CSF is mainly produced within the .

A. central canal

B. dural sinuses

C. brain ventricles

D. cerebral aqueduct

E. subarachnoid space

12. Which is false about the veins of brain?

A. The cerebral veins do not run together with the arteries.

B. It divided into superficial and deep groups.

C. The superficial vein empty into the straight sinus.

D. The superficial vein drain the blood from cerebral cortex~

E. The deep vein empty into the straight sinus.

13. The allow(s) CSF to flow from the third ventricle to the fourth ventricle.

A. dural sinuses

B. arachnoid granulations

C. choroid plexuses

D. cerebral aqueduct

E. median and lateral apertures

14. The is/are directly involved in the re. absorption of CSF.

A. central canal

B. arachnoid granulations

C. choroid plexuses

D. cerebral aqueduct

E. median and lateral apertures

15. Which of the following is not associated with the cranial meninges?

A. epidural space containing fats and veins

B. dura mater continuous with the periosteal layer

C. venous sinuses

D. pia mater containing blood vessels

E. arachnoid granulations

16. Which statement about blood vessels of the brain is true?

A. The middle cerebral artery is a branch of the internal carotid artery.

B. The great cerebral vein (of Galen) drains into the superior sagittal sinus.

C. The posterior cerebral artery is a branch of the vertebral artery.

D. The basilar artery enters the cranial cavity through the foramen magnum.

E. The anterior communicating artery connects the two middle cerebral arteries.

17. What is not there in the cavernous sinus?

A. the internal carotid artery

B. the internal jugular vein

C. the abducent nerve

D. the oculomotor nerve

E. the trochlear nerve

18. What are the main sources of cerebrospinal fluid?

A. the choroid plexuses

B. the cerebral pia mater

C. the internal carotid artery

D. the internal jugular vein

E. the vertebral artery

19. Which is true about the middle cerebral artery?

A. It supplies little of the dorsolateral surface of the cerebral hemisphere.

B. It arises from the subclavian artery.

C. It forms the cerebral arterial circle.

D. It runs horizontally to the lateral sulcus.

E. It descends to the lateral sulcus.

20. Which is true about the brain barrier?

A. Its function is to stable the environment surrounding the neurons.

B. It is composed of four parts.

C. It is just in between blood and neuron in the brain and spinal cord.

D. It consists the capillary endothelium homogenous basement and neuroglial membrane.

E. All areas in brain have a blood-brain barrier.

21. A person develops a cavernous sinus thrombosis. Because of its relationship to the sinus, which cranial nerve might be affected?

A. abducent

B. facial

C. mandibular V3

D. olfactory

E. optic

22. The inferior sagittal sinus is found in the free edge of what structure?

A. diaphragma sellae

B. cerebellar falx

C. cerebral falx

D. ilium terminale

E. tentorium of cerebellum

23. Which statement about ventricles is false?

A. They contain cerebrospinal fluid.

B. They contain the choroid plexus.

C. The inferior horns of the lateral ventricles project into the temporal lobes.

D. The caudate nucleus contributes to the walls of the lateral ventricle.

E. The interventricular foramen connects the third with the fourth ventricle.

24. Which statement about the epidural space is false?

A. It is a space between the dura and the periosteum of the vertebral canal.

B. It contains a quantity of loose areolar tissue.

C. It contains lymphatic vessels and venous plexuses.

D. The spinal nerves on each side pass through it.

E. There is cerebrospinal fluid in the space.

25. Which statement about the cerebral dura mater is true?

A. It is the inner periosteum of the skull.

B. It is in closely connected with the calvaria.

C. It is loosely attached at the base of skull.

D. Cerebrospinal fluid may leak out from the nose or ear with a fracture of the base of skull.

E. Sometimes, it is also the arachnoid.

26. The most likely source of blood in a patient with an epidural hemorrhage is the .

A. vertebral artery

B. middle meningeal artery

C. superior cerebral veins

D. anterior cerebral artery

E. circle of Willis

27. The patient's ventricle was injected into trypan blue and observed that the CSF turns blue but the brain tissue does not. This represents an example of .

A. blood-brain barrier

B. blood-CSF barrier

C. CSF-brain barrier

D. CSF-blood barrier

E. blood-blood barrier

28. Which of the following is/are true of the blood brain barrier (BBB)?

A. The BBB is located around the cerebral arterial circle and cerebral arteries.

B. The BBB is located on the walls of the brain ventricles and is involved in the production of cerebrospinal fluid.

C. The BBB is composed of neuroglial cells called astrocytes.

D. The BBB controls the passage of chemical substances into the neurons of the brain.

E. The BBB is permeable to oxygen, carbon dioxide, and glucose.

29. Which artery is not formed the cerebral arterial circle?

A. the anterior cerebral arteries

B. the posterior inferior cerebellar arteries

C. the posterior cerebral arteries

D. a short segment of internal carotid arteries

E. the posterior communicating arteries

30. The direction of the blood flow in the sinuses of dura mater is as follows .

A. inferior sagittal sinus-transverse sinuses-confluence of the sinuses-internal jugular vein

B. cavernous sinus--inferior petrosal sinus-internal jugular vein

C. superior sagittal sinus-inferior petrosal sinus-internal jugular vein

D. sigmoid sinus--transverse sinuses-confluence of the sinuses-internal jugular vein

E. straight sinus--superior petrosal sinus--internal jugular vein

31. The internal capsule is mainly supplied by the .

A. direct branches of the internal carotid arteries

B. direct branches of the middle cerebral arteries

C. direct branches of the cerebral arterial circle

D. direct branches of the posterior cerebral arteries

E. direct branches of the basilar artery

32. Which is not the branch of the basilar artery?

A. the anterior inferior cerebellar artery

B. the middle cerebral arteries

C. the posterior cerebral arteries

D. the artery to the labyrinth

E. the superior cerebellar artery

33. Which arteries supply blood to the medial portions of the frontal and parietal lobes?

A. the anterior inferior cerebellar artery

B. the anterior cerebral arteries

C. the posterior cerebral arteries

D. the middle cerebral arteries

E. the superior cerebellar artery

34. The occipital lobe is supplied by the .

A. middle cerebral artery

B. posterior cerebral artery

C. anterior inferior cerebellar artery

D. superior cerebellar artery

E. anterior cerebral artery

35. The auditory and language cortical areas is supplied by the .

A. posterior communicating artery

B. middle cerebral artery

C. posterior cerebral artery

D. superior cerebellar artery

E. anterior cerebral artery

36. All of the following statements pertain to the spinal pia mater except:

A. It forms one of the boundaries of the subarachnoid space.

B. It forms the filum terminale.

C. It is adherent to the spinal cord.

D. It supports the anterior and posterior spinal arteries.

E. It terminates at the foramen magnum.

37. Cerebrospinal fluid enters the subarachnoid space at the .

A. arachnoid granulations

B. choroids plexuses

C. median and lateral apertures of the fourth ventricle

D. interventricular foramen

E. mesencephalic aqueduct

38. Cerebrospinal fluid enters the venous system .

A. at arachnoid granulations

B. at the cisterna magna

C. through subarachnoid veins

D. via capillaries in the central nervous system

E. through mesencephalic aqueduct

39. All of the following arteries are branches of the internal carotid artery except the .

A. anterior cerebral arteries

B. middle cerebral arteries

C. ophthalmic arteries

D. posterior cerebral arteries

E. posterior communication arteries

A2

1. Blockage of the flow of cerebrospinal fluid (CSF) within the cerebral aqueduct (of Sylvius) normally would result in the enlargement of all of the following ventricular spaces except the .



A. third ventricle

B. fourth ventriclee

C. right lateral ventricle

D. interventricular foramen

E. left lateral ventricle

2. During childbirth, an excessive anteroposterior compression of the head may tear the anterior attachment of the cerebral falx from the tentorium of cerebellum. The bleeding that follows is likely to be from which of the following venous sinuses?

A. occipital sinus

B. sigmoid sinus

C. straight sinus

D. superior sagittal sinus

E. transverse sinus

3. An infant was found to have hydrocephalus. Studies revealed that the hydrocephalus was caused because CSF could not get out of the third ventricle. The blocked passage was the .

A. central canal

B. cerebral aqueduct

C. interventricular foramen

D. lateral foramen

E. medial foramen

4. A patient is suspected of having bacterial meningitis. A lumbar puncture is performed to remove cerebrospinal fluid for analysis. The fluid would be removed from the .

A. epidural space

B. subarachnoid space

C. intervertebral foramen

D. spinal canal

E. subdural space

5. It is decided to image the spinal cord and spinal nerve rootlets by doing a myelogram (injection of a radio-opaque dye into the subarachnoid space followed by a radiograph). In order to inject the dye without injury to the spinal cord, the injection is usually done below which vertebral level?

A. C7

B. T12


C. IA

D. S2


E. L1

6. You have been asked to assess the neurological deficit that might exist in a patient diagnosed with cavernous sinus thrombosis. You will focus your examination on cranial nerves related to the sinus that includes all the following except .

A. abducent (CN Ⅵ)

B. facial (CN Ⅶ)

C. oculomotor (CN Ⅲ)

D. ophthalmic division of the trigeminal nerve (CN Ⅵ)

E. trochlear (CN Ⅳ)

7. While riding her bicycle on campus without a helmet a student is hit by a car and falls, hitting her head on the pavement. She is brought to the Emergency Room in an unconscious state with signs of a closed head injury. Tests reveal blood in her cerebrospinal fluid taken from a spinal tap. Diagnosis is of torn cerebral veins as they pass from the brain to the superior sagittal sinus. From which of the following was the bloody fluid taken?

A. cavernous sinus

B. epidural space

C. subarachnoid space

D. subdural space

E. vertebral venous plexus

8. A 35-year-old man was admitted to the hospital complaining of double vision (diplopia), inability to see close objects, and blurred vision in the fight eye. A vertebrohasilar angiogram revealed an aneurysm of the superior cerebellar artery close to its origin on the right side. The doctor attributed the symptoms to the compression of an adjacent cranial nerve by the aneurysm The compressed nerve is the .

A. abducent (CN Ⅵ)

B. oculomotor (CN Ⅲ)

C. optic (CN Ⅱ)

D. trigeminal (CN Ⅴ)

E. trochlear (CN Ⅳ)

9. During an intramural baseball game a player is hit on the head, between the eye and the ear. He immediately loses consciousness, wakes up momentarily and then becomes comatose. He is rushed to the ER and immediately given a CT scare The scan shows a skull fracture and an accumulation of blood between the dura and the cranial bone on the side of his head, compressing his cerebrum. He is rushed to surgery where a hole is bored into his skull to relieve the pressure. After a few tense hours, he regains consciousness and has an uneventful recovery. The hemorrhage from the fracture would be described as

A. epidural

B. intracerebral

C. subaponeurotic

D. subarachnoid

E. subdural

10. An 84-year old woman suffers a stroke, with paralysis on the right side of her body. Neurological tests show that the intracerebral hemorrhage has interrupted the blood supply to the posterior part of the frontal, the parietal and medial portions of the temporal lobes of the left cerebral hemisphere. Which vessel was involved?

A. anterior cerebral artery

B. great cerebral vein

C. middle cerebral artery

D. middle meningeal artery

E. posterior cerebral artery

B1

A. contains cerebrospinal fluid



B. innermost layer of the spinal meninges

C. contains a quantity of loose areolar tissue

D. sensitive to pain

E. dense fibrous connective tissue

1. pia mater

2. subarachnoid space

A. the posterior communicating artery

B. the anterior cerebral artery

C. the middle cerebral artery

D. the anterior choroidal artery

E. the posterior cerebral artery

3. Which is not included in the circle of Willis?

4. Which is not the branch of internal carotid arteries?

A. the arachnoid granulations

B. the denticulate ligament

C. the subarachnoid space

D. the choroids plexuses

E. the tentorium of cerebellum

5. Which is formed by the cerebral dura mater?

6. Which is formed by the arachnoid?

7. Which is formed by the spinal pia mater?

A. the superior sagittal sinus

B. the straight sinus

C. the transverse sinuses

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