BRAIN (NERVOUS SYSTEM) MCQs

Most patients with intrinsic brainstem gliomas initially present with :

A. Cranial neuropathies 

B. Headache 

C. Hydrocephalus

 D. Nausea and vomiting 

E. Papilledema

ANSWER Cranial neuropathies The initial symptoms in most patients with brainstem gliom as are cranial neuropathies  followed by weakness or ataxia. Headache , nausea and vomiting , and papilledema  usually occur later in the course of the illness.

Which approach is favored for a patient with an 8-mm acoustic neuroma in which hearing preservation is a goal? 

A. Middle fossa 

B. Suboccipital 

C. Translabyrinthine

ANSWER Middle fossa This question is based on the assumption that an 8 mm acoustic neuroma would be an intracanalicular lesion. Small ( 1cm ) intracanalicular acoustic neuromas can easily be approached via the middle fossa route. A translabyrinthine approach would sacrice hearing. The middle fossa approach is preferred to a suboccipital , retrosigmoid approach for intracanalicular lesions.

Uncinate seizures typically produce 

A. Auditory hallucinations 

B. Gustatory hallucinations 

C. Olfactory hallucinations 

D. Vertiginous sensations 

E. Visual seizures

ANSWER Olfactory hallucinations Seizure foci in the mesial temporal lobe (uncinate seizures) tend to produce olfactory hallucinations . Auditory hallucinations intuitively would seem to be associated with a focus near Heschl’s gyrus, but the data do not support that assumption. Gustatory hallucinations are rare and can be brought about by stimulation of the posterior insula. Vertiginous sensations are associated with foci in the superoposterior temporal lobe near the junction with the parietal lobe. Visual seizures suggest a focus in the striate cortex of the occipital lobe

Each of the following is true of intraventricular hemorrhage (IVH) in the new born except 

A. Periventricular hemorrhagic infarction is one sequela. 

B. Posthem orrhagic hydrocephalus can result in persistent bradycardia and apneic spells. 

C. The capillary bed of the germ inal m atrix is composed of large irregular vessels. 

D. The germ inal m atrix is the m ost com m on site of IVH in the full-term neonate. 

E. The risk of IVH is greater in the preterm than in the term infant.

ANSWER The germ inal m atrix is the most common site of IVH in the full-term neonate (false). The germinal matrix is the most comm on site of IVH in the preterm infant, not the full-term infant as presented in the question (D). The most common site of IVH in the full-term neonate is the choroid plexus. The germinal matrix is characterized by a capillary bed of large irregular vessels (C) and begins to involute at 43 weeks. The risk of IVH is greater in the preterm than the term infant (E) and can lead to periventricular hemorrhagic infarction (A) as well as post hemorrhagic hydrocephalus leading to persistent bradycardia and apneic spells (B).

The most common single-suture synostosis is 

A. Coronal 

B. Lam bdoid 

C. Metopic 

D. Sagittal 

E. Sphenozygomatic

ANSWER Sagittal synostosis Isolated sagittal synostosis (D) causes scaphocephaly and is the most common single-suture synostosis, accounting for up to 50% of craniosynostosis patients in some series. Metopic synostosis (C) causes trigonocephaly; coronal synostosis (A) causes anterior plagiocephaly and is less common than sagittal synostosis. Lambdoid and sphenozygomatic synostosis (B, E) are both less common than sagittal synostosis

Coup contusions most commonly occur at the: 

A. Cerebral convexities 

B. Frontal and temporal poles 

C. Orbital surface of the frontal lobes 

D. Posterior fossa 

E. Ventral surface of the temporal lobe

ANSWER Cerebral convexities Contrecoup contusions, produced by rotational force, occur where the frontal and temporal lobes rub along bony prominences (B, C, E). Coup contusions (the least common type) are located over the cerebral convexities (A).

Each of the following is true of basilar impression except: 

A. Cerebellar and vestibular complaints typically overshadow motor and sensory complaints. 

B. McGregor’s line is helpful in routine screening. 

C. McRae’s line is helpful in clinical assessment. 

D. Short necks and torticollis are common. 

E. Vertebral artery anom alies are common.

ANSWER Cerebellar and vestibular complaints typically overshadow motor and sensory complaints (false). In cases of basilar impression, motor and sensory complaints are seen more often than are cerebellar and vestibular symptoms. The lines of McGregor (B) and McRae (C) may be helpful in the radiographic assessment of patients with basilar invagination. Short necks, torticollis (D), and vertebral artery anomalies (E) are common in patients with basilar invagination.

“Trilateral retinoblastoma” describes bilateral ocular retinoblastomas and a(n) 

A. Astrocytoma 

B. Medulloblastoma 

C. Neurofibroma 

D. Optic nerve sheath tumor 

E. Pineoblastoma

ANSWER Pineoblastoma The presence of bilateral ocular retinoblastomas along with the presence of a pineoblastoma (E) is known as “trilateral retinoblastoma.” An understanding of this association is facilitated by the recognition that the pineal gland is a photoreceptor organ. Astrocytoma (A), medulloblastom a (B), neurofibroma (C), and optic nerve sheath tumor (D) are incorrect responses

Carotid artery ligation is absolutely contraindicated in patients w ith (a) 

 A. Bilateral intracavernous carotid aneurysms 

B. Giant ophthalmic artery aneurysm and evidence of vasospasm on arteriogram 

C. Giant ophthalmic artery aneurysm and extracranial atherosclerotic disease 

D. Intracavernous carotid artery aneurysm and sudden loss of extraocular motility 

E. Traumatic dissecting aneurysm of the petrous carotid artery

ANSWER Giant ophthalmic artery aneurysm and evidence of vasospasm on arteriogram Evidence of vasospasm on arteriogram (B) implies the potential for inadequate collateral flow, which would put the patient at risk for ischemic neurologic deficits following vessel sacrice. While the presence of bilateral intracavernous carotid aneurysms (A) or extracranial atherosclerotic disease (C) may be relative contraindications to carotid sacrice in this clinical scenario, they do not represent absolute contraindications. Carotid artery ligation is not contraindicated in the setting of sudden loss of extraocular motility in the presence of an intracavernous carotid artery aneurysm (D) or in the setting of traumatic dissecting aneurysm of the petrous carotid artery (E)

Which of the following findings is most consistent with adherence of a posterior communicating artery aneurysm to the temporal lobe? 

 A. Loss of consciousness 

B. Absence of third nerve palsy 

C. Projection of the aneurysm medial to the carotid on the anteroposterior (AP) angiogram 

D. Third nerve involvement 

E. Seizures

ANSWER Absence of third nerve palsy Patients with posterior communication artery aneurysms who do not have a third nerve palsy (B) or whose angiogram reveals the aneurysm projecting laterally to the carotid are more likely to have aneurysm domes that are adherent to the temporal lobe. Choices C and D are incorrect because they contradict this statement. Neither loss of consciousness (A) nor seizures (E) predict aneurysm adherence to the temporal lobe.

Subdural empyema resulting after meningitis in an infant most commonly develops with: 

 A. Escherichia coli 

B. Haemophilus influenzae 

C. Listeria 

D. Neisseria 

E. Staphylococcus

ANSWER Escherichia coli E. coli (A) is the most common cause of subdural empyema in the infant following meningitis. Streptococcus pneumoniae meningitis may also lead to subdural empyemas. Listeria (C), Neisseria (D), and Staphylococcus (E) are incorrect responses.

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Match the embryologic event with the postovulatory day. Each response may be used once, more than once, or not at all. 

 Postovulatory Day Number 

A. 13 

B. 17 

C. 22 

D. 24 

E. 26

ANSWER A – Formation of the primitive streak: Day 13 

B – Form ation of the notochord: Day 17 

C – Fusion of the neural folds to form the neural tube: Day 22 

D – Closure of the cranial neuropore: Day 24 

E – Closure of the caudal neuropore: Day 26

Each of the following features is usually minimal or absent in patients with type 2 neurofibromatosis except

A. Axillary freckles

B. Café au lait spots

C. Lisch nodules

D. Multiple, typical skin neurofibromatosis

E. Skin plaques 

ANSWER : Skin plaques (false)

Skin plaques  are the most common skin lesions seen in neurofibromatosis type 2. They are well-circumscribed, raised, rough areas of skin that may be associated with excess hair. Axillary freckles , café au lait spots , Lisch nodules , and multiple typical skin neurofibromas  are all characteristics of neurofibromatosis type 1.

The single most important factor in the recurrence of meningiomas is

A. Age of the patient

B. Bone invasion

C. Histologic type of benign meningioma

D. Postoperative tumor residual

E. Sex of the patient

ANSWER : Postoperative tumor residual  is the most important factor in meningioma recurrence. Bone invasion could influence recurrence rates as it may limit the extent of tumor resection, particularly for lesions at the skull base. Histologic type of benign meningioma  is incorrect because this answer choice implies that the lesion is WHO grade I. Certainly WHO grade II (atypical) and WHO grade III (anaplastic) meningiomas have a higher recurrence rate than grade I (benign) lesions, but this is not an answer choice. Patient age  and sex  are incorrect responses.

Match the cistern with the structure it contains. Each response may be used once, more than once, or not at all.

A. Ambient cistern

B. Cerebellopontine angle cistern

C. Interpeduncular cistern

D. Lateral cerebellomedullary cistern

E. Prepontine cistern

ANSWER :

Cerebellopontine angle cistern : Contains the anteroinferior cerebellar artery (AICA)

Lateral cerebellom edullary cistern : Contains the origin of the posteroinferior cerebellar artery (PICA)

Ambient cistern : Contains the superior cerebellar artery 

Ambient cistern : Contains cranial nerve (CN) IV

 Cerebellopontine angle cistern : Contains CN V

  Interpeduncular cistern : Contains the basal vein of Rosenthal

Lateral cerebellom edullary cistern : Contains the choroid plexus at the foram en of Luschka

The transverse crest separates the: 

A. Cochlear, facial, and superior vestibular nerves from the inferior vestibular nerve

B. Cochlear and inferior vestibular nerves from the facial and superior vestibular nerves

C. Facial and cochlear nerves from the superior and inferior vestibular nerves

D. Facial, cochlear, and inferior vestibular nerves from the superior vestibular nerve

E. Facial and inferior vestibular nerves from the cochlear and superior vestibular nerves

ANSWER : Cochlear and inferior vestibular nerves from the facial and superior vestibular nerves.

Which of the following is true of hemifacial spasm ?

A. Compression of the facial nerve by the superior cerebellar artery is the most common operative finding.

B. Deafness is more common than permanent facial weakness as a complication of microvascular decompression.

C. Men are more frequently affected than women.

D. Symptoms typically begin in the buccal muscles and move cranially.

E. The cure rate at 1 month after microvascular decompression is 95%

ANSWER : Deafness is more common than permanent facial weakness as a complication of microvascular decompression.

Hemifacial spasm is more common in females (C is incorrect); it typically begins in the orbicularis muscles and progresses caudally (D is incorrect). At microvascular decompression the most common finding is compression by the posteroinferior cerebellar artery (PICA) (A is incorrect); the cure rate at 1 month is 86% (E is incorrect). Deafness occurs in 2.7% of patients, and permanent facial weakness occurs in 1.5% of patients after microvascular decompression (B is correct).

Each of the following surgical approaches may be considered for an aneurysm of the vertebrobasilar junction except the:

A. Extended extreme lateral inferior transcondylar approach

B. Lateral suboccipital approach

C. Presigmoid transtentorial approach

D. Retrolabyrinthine transsigmoid approach

E. Subtemporal approach

ANSWER : Subtemporal approach

The most common presenting symptom in patients with colloid cysts is:

A. Headache

B. Dementia

C. Seizures

D. Sudden attacks of leg weakness

E. Sudden death

ANSWER : Headache (A) is the initial symptom in m ore than 75% of patients with colloid cysts, and almost all patients with this lesion experience headache. “Drop attacks,” possibly secondary to acute hydrocephalus that suddenly stretches corticospinal leg fibers (sudden leg weakness [D]), are associated with colloid cysts. Dementia (B) may be prominent, and seizures (C) occur in 20% of patients. An association with sudden death (E) has been reported.

The most common presenting symptom of neonates with vein of Galen aneurysms is:

A. Congestive heart failure

B. Hydrocephalus

C. Intracerebral hemorrhage

D. Seizures

E. Subarachnoid hem orrhage

ANSWER : Congestive heart failure . Neonates with congestive heart failure (A) usually have multiple fistulas, and over 25% of their cardiac output is shunted. Hydrocephalus (B) and seizures (D) are more common in infants, whereas subarachnoid hemorrhage (E), decreased cognition, and intraparenchymal hemorrhage (C) are more common in older children and adults.

Each of the following is true of diffuse brain swelling except that it is

A. A result of cerebrovascular congestion

B. A result of cytotoxic edema

C. Associated with a 50% mortality rate in children with severe head injuries

D. Manifested on computed tomography (CT) scan by a compression of the perimesencephalic cistern

E. More common in children than in adults

ANSWER : A result of cytotoxic edema (false) . Diffuse brain swelling is a vasoactive posttraumatic phenomenon occurring within hours of head injury. It is thought to be a result of cerebrovascular congestion (A) and can be manifested on CT scan by a compression of the perimesencephalic cistern (D). This pathologic process is more common in children than adults (E), and may be associated with a 50% mortality rate in severely head injured children (C). It is distinct from the vasogenic or cytotoxic edema (B) that occurs later

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The average total brain H20 content is: 

A. 50% 

B. 55% 

C. 60% 

D. 78% 

E. 90%

ANSWER : D. 78% 

Which of the following is the principle visceral nucleus of the brain stem?

A. Nucleus ambiguus 

B. Raphe nucleus 

C. Nucleus solitarius 

D. Locus ceruleus 

E. Trigeminal nucleus

ANSWER : C. Nucleus solitarius 

Sodium content in normal saline solution most closely approximates:

A. 0.9 g/L 

B. 4.8 g/L

C. 9 mg/L 

D. 9 g/L

ANSWER : D. 9 g/L

Which of the following is the only paired circumventricular organ? 

A. Fornix 

B. Area postrema 

C. Corpus callosum 

D. Entorhinal cortex 

E. Inferior peduncle

ANSWER : B. Area postrema 

In trisomy 21 the most common subband abnormality is:

A. Duplication of 21 q22 

B. Triplication of 21 q22 

C. Duplication of 22.3

D. Duplication of 17 q 

E.Triplication of 17q

ANSWER : B. Triplication of 21 q22 

What is the most common autosomal chromosomal abnormality in human live births? 

A. Trisomy 21 (Down's syndrome)

B. Trisomy 18 (Edward's syndrome) 

C. Trisomy 13 (Patau's syndrome)

D. Klinefelter's syndrome 

E. Prader-Willi syndrome

ANSWER : A. Trisomy 21 (Down's syndrome)

The gene locus responsible for neurofibromatosis type I is located on: 

A. Xq27.3

B. 17q11.2 

C. 22q11.1 

D. 15q11 

E. 21q21

ANSWER : B. 17q11.2 

The gene locus responsible for NF-2 is located on chromosome: 

A. Xq27.3

B. 17q11.2 

C. 22q11.1 

D. 15q11 

E. 21q21

ANSWER : C. 22q11.1

Neural tube closure initiates at the: 

A. Caudal rhombencephalon

B. Caudal prosencephalon 

C. Rostral rhombencephalon 

D. Rostral prosencephalon

ANSWER : A. Caudal rhombencephalon

Which of the following statements is correct regarding the development of the conus medullaris?

A. The ascent of the conus medullaris is due primarily to a disparity between the growth rates of the vertebral column and the spinal cord.

B. At 18 weeks' gestation, the conus medullaris is situated at the level of the L2 vertebrae.

C. At term, nearly all fetuses show the conus medullaris above the T12 vertebrae. 

D. There is no known relation of the level of the conus medullaris to the vertebral body.

ANSWER : A.

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Which signal transduction protein is important in the development of both the vertebral column and the spinal cord?

1. Meromyosin 
2.  Insulin 
3. Myosin
4. Sonic hedgehog 
5. Neurofilament

ANSWER :  Sonic hedgehog 

Schwann cells derive from: 

1. Neural tube cells
2. Mesoderm germ layer 
3. Neural crest cells 
4. Endoderm germ layer

ANSWER : Neural crest cells 

The metopic suture generally ossifies during the: 

1. First year of life 
2. Second year of life 
3. Third year of life 
4. Fourth year of life

ANSWER : Second year of life 

The coronal suture is usually obliterated and ossifies around: 

1. 7 years of age
2. 10 years of age 
3. 24 years of age 
4. 55 years of age

ANSWER : 24 years of age 

Each of the following is true of diffuse brain swelling except that it is

1. A result of cerebrovascular congestion
2. A result of cytotoxic edema
3. Associated w ith a 50% m ortality rate in children w ith severe head injuries
4. Manifested on computed tomography (CT) scan by a com pression of the perimesencephalic cistern
5. More common in children than in adults 

ANSWER : A result of cytotoxic edema

Which of the follow ing is least suggestive of child abuse?

1. Acute and healing long bone fractures
2. Interhem ispheric subdural hematoma
3. Parietal skull fracture
4. Retinal hem orrhages
5. Tentorial subdural hematoma

ANSWER :Parietal skull fracture

Trigonocephaly results from premature closure of the

1. Coronal suture bilaterally
2. Coronal suture unilaterally
3. Frontosphenoidal suture
4. Lam bdoid suture
5. Metopic suture

ANSWER : Metopic suture

Up to what percentage of patients with bacterial arterial (mycotic) aneurysms carry an underlying diagnosis of subacute bacterial endocarditis?

1.  10%
2.  20%
3.  40%
4.  60%
5.  80%

ANSWER : 80%

Each is true of bacterial intracranial aneurysms except:

1. Infected emboli lodge in the vasa vasorum .
2. The middle cerebral artery is most commonly affected.
3. The peripherally located branches are most commonly affected.
4. Typical subarachnoid hem orrhage occurs in 18% of patients.
5. Staphylococcus aureus and b-hemolytic streptococci are most commonly involved.

ANSWER : Infected emboli lodge in the vasa vasorum .

Each of the following is true of growing skull fractures except that they:

1. Can cross suture lines
2. May be associated with underlying brain injury
3. Occur if the edges of the initial fracture are separated by more than 3 mm
4. Occur most commonly in the parietal bone
5. Occur most commonly between the ages of 2 and 5 years

ANSWER : Occur most commonly between the ages of 2 and 5 years (1 year old)

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Each of the following is characteristic of an acoustic neuroma except:

1. Békésy type III or IV audiogram
2. Loudness recruitment
3. Low short-increm ent sensitivity index
4. Poor speech discrim ination
5. Pronounced tone decay

ANSWER : Loudness recruitment

Which of the following symptom s of Parkinson’s disease is most likely to respond to a stereotactic lesion in the posterior ventral oval (VOP)/ventral intermediate (VIM) (ventrolateral) thalamus?

1. Bradykinesia
2. Gait disturbance
3. Rigidity
4. Speech disturbance
5. Tremor

ANSWER : Tremor

The factor  with the least important role in the pathogenesis of cerebral vasospasm is probably:

1. Bilirubin
2. Endothelin
3. Intimal proliferation
4. Lipid peroxides
5. Oxyhem oglobin

ANSWER : Intimal proliferation

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