50 Neurology Multiple-Choice Questions for Medical Students
Question 1
A 72-year-old woman presents with progressive gait instability, urinary urgency, and mild cognitive decline over 6 months. Brain MRI shows ventriculomegaly with periventricular white matter changes. What is the most appropriate next diagnostic step?
A) Start acetazolamide therapy
B) Perform lumbar puncture with CSF drainage and gait velocity testing
C) Refer for immediate ventriculoperitoneal shunt placement
D) Order FDG-PET scan
Answer: B
Explanation: In suspected idiopathic normal-pressure hydrocephalus (iNPH), temporary CSF drainage with gait velocity measurement is the gold standard for selecting patients who will benefit from shunt surgery 1. The PENS trial demonstrated that among patients who showed gait velocity improvement with CSF drainage, shunting resulted in significant improvements at 3 months (mean increase 0.23 m/s in open-shunt vs 0.03 m/s in placebo, P<0.001) 1. This pre-operative test predicts surgical response and is essential before proceeding to permanent shunt placement 1.
Question 2
A 45-year-old man with newly diagnosed atrial fibrillation (CHA₂DS₂-VASc score 3) asks about stroke prevention options. He is concerned about bleeding risk. Which statement about factor XI inhibition is most accurate?
A) Factor XI inhibitors have similar bleeding rates to rivaroxaban
B) Abelacimab reduces free factor XI by approximately 50%
C) Abelacimab demonstrates 62-69% lower bleeding rates compared to rivaroxaban
D) Factor XI inhibitors require daily oral administration
Answer: C
Explanation: Abelacimab, a monoclonal antibody targeting factor XI, resulted in markedly fewer bleeding events than rivaroxaban in the AZALEA-TIMI 71 trial 2. The incidence of major or clinically relevant nonmajor bleeding was 3.2 events per 100 person-years with 150-mg abelacimab and 2.6 events per 100 person-years with 90-mg abelacimab, compared with 8.4 events per 100 person-years with rivaroxaban (hazard ratios 0.38 and 0.31 respectively, P<0.001 for both) 2. Abelacimab reduced free factor XI levels by 97-99% and is administered monthly via subcutaneous injection 2.
Question 3
A 28-year-old woman with multiple café-au-lait macules and axillary freckling is diagnosed with neurofibromatosis type 1. What is the approximate prevalence of this condition?
A) 1:500
B) 1:2500 to 1:3500
C) 1:10,000
D) 1:50,000
Answer: B
Explanation: Neurofibromatosis type 1 (NF1) affects approximately 1:2500 to 1:3500 individuals worldwide, regardless of ethnicity or race 3. This makes NF1 one of the more common neurogenetic disorders 3. Classic manifestations include café-au-lait macules, skinfold freckling, neurofibromas, brain tumors, iris hamartomas, and characteristic bony lesions 3.
Question 4
A 3-year-old boy with global developmental delay has normal metabolic screening. His parents are requesting genetic testing. According to current guidelines, what should be the first-tier genetic test?
A) Whole exome sequencing
B) Chromosomal microarray (CMA) and Fragile X testing
C) MECP2 sequencing
D) Karyotype analysis
Answer: B
Explanation: For unexplained global developmental delay (GDD), the American Academy of Pediatrics recommends chromosomal microarray (CMA) and Fragile X testing as first-tier tests in all patients 4. According to 2020 AAP guidelines, if no specific diagnosis is suspected after comprehensive history and physical examination, CMA and Fragile X analysis should be discussed and offered 4. If first-tier tests are unrevealing, consider referral to genetics for additional workup that might include exome sequencing 4.
Question 5
A 65-year-old man with suspected Alzheimer's disease undergoes neuropathologic assessment. The ABC score shows A3, B3, C3. What level of AD neuropathologic change does this represent?
A) Not AD
B) Low
C) Intermediate
D) High
Answer: D
Explanation: According to the NIA-Alzheimer's Association guidelines, an ABC score of A3, B3, C3 indicates "High" AD neuropathologic change 4. The ABC scoring system combines Aβ/amyloid plaques (A), neurofibrillary tangle stage by Braak method (B), and neuritic plaque score by CERAD method (C) 4. "High" AD neuropathologic change is considered sufficient explanation for dementia 4.
Question 6
A 58-year-old woman presents with progressive weakness, fasciculations, and hyperreflexia. EMG shows widespread denervation. What additional test is mandatory to confirm the diagnosis of ALS?
A) Muscle biopsy
B) Nerve conduction velocity studies
C) Genetic testing for SOD1
D) Brain MRI with contrast
Answer: B
Explanation: The American Academy of Neurology recommends EMG and nerve conduction velocity (NCV) studies as mandatory for detecting lower motor neuron degeneration and distinguishing ALS from other conditions 5. NCV studies help exclude other diagnoses such as multifocal motor neuropathy and other peripheral nerve disorders that can mimic ALS 5.
Question 7
In a patient with suspected ALS, brain MRI shows T2/FLAIR hyperintensity in the posterior limb of the internal capsule. What does this finding suggest?
A) Multiple sclerosis
B) Corticospinal tract involvement consistent with ALS
C) Normal aging changes
D) Acute stroke
Answer: B
Explanation: The American College of Radiology suggests looking for abnormal T2/FLAIR hyperintensity in the corticospinal tracts, particularly in the posterior limb of the internal capsule and cerebral peduncles, as a finding consistent with ALS 5. Additionally, T2*-weighted or susceptibility-weighted imaging may show abnormal hypointensity in the precentral gyrus, which can be highly sensitive and specific for ALS 5.
Question 8
A 42-year-old man with ALS and a family history of frontotemporal dementia should undergo genetic testing for which gene first?
A) SOD1
B) C9orf72
C) FUS
D) TARDBP
Answer: B
Explanation: The American College of Medical Genetics suggests testing for key ALS-associated genes including C9orf72, SOD1, FUS, and TARDBP, with C9orf72 being particularly important when there is a family history of ALS or frontotemporal dementia 5. C9orf72 repeat expansion is the most common genetic cause of both familial ALS and frontotemporal dementia 5.
Question 9
A 70-year-old woman with ALS has no bulbar symptoms but scores 12 on the EAT-10 questionnaire. What is the sensitivity and specificity of this tool for detecting unsafe swallowing?
A) 50% sensitivity, 50% specificity
B) 70% sensitivity, 60% specificity
C) 86% sensitivity, 76% specificity
D) 95% sensitivity, 90% specificity
Answer: C
Explanation: The American Academy of Otolaryngology suggests using the EAT-10 questionnaire, which has 86% sensitivity and 76% specificity for identifying unsafe swallowing 5. The American Speech-Language-Hearing Association recommends dysphagia screening at diagnosis and every 3 months thereafter as part of comprehensive evaluation in ALS patients 5.
Question 10
A 4-year-old girl with autism spectrum disorder undergoes chromosomal microarray, which is normal. She is female with no dysmorphic features. What is the most appropriate next genetic test?
A) Fragile X testing
B) MECP2 sequencing
C) PTEN testing
D) Karyotype
Answer: B
Explanation: According to the American College of Medical Genetics 2013 guidelines, MECP2 sequencing should be performed for all females with unexplained autism when first-tier testing (CMA and Fragile X) is unrevealing 4. The 2020 AAP guidelines also recommend considering MECP2 testing in female patients with ASD 4.
Question 11
A 5-year-old boy with autism has a head circumference 3 standard deviations above the mean. Which gene should be tested?
A) MECP2
B) PTEN
C) FMR1
D) UBE3A
Answer: B
Explanation: The American College of Medical Genetics recommends PTEN testing if head circumference is >2.5 SD above the mean in patients with autism 4. PTEN mutations are associated with macrocephaly and autism spectrum disorder 4.
Question 12
In transcranial magnetic stimulation (TMS) trials for addiction medicine, what percentage of studies targeted the dorsolateral prefrontal cortex (DLPFC)?
A) 25%
B) 50%
C) 75%
D) 92%
Answer: D
Explanation: Seventy-seven out of 84 published TMS/tDCS studies (92%) selected DLPFC as the target of stimulation, including right, left, or bilateral DLPFC 4. This makes the DLPFC by far the most commonly targeted brain region in addiction medicine trials using neuromodulation 4.
Question 13
A patient with alcohol use disorder is being considered for repetitive TMS. What is the most commonly used frequency for stimulating the left DLPFC in addiction trials?
A) 1 Hz
B) 5 Hz
C) 10 Hz
D) 20 Hz
Answer: C
Explanation: For left DLPFC stimulation in addiction medicine trials, 10 Hz repetitive TMS was the most commonly used protocol, employed in 16 out of 29 TMS studies targeting this region 4. Other frequencies used included 15 Hz (3 studies), 20 Hz (5 studies), and combinations of frequencies 4.
Question 14
A 68-year-old man is comatose 48 hours after cardiac arrest with return of spontaneous circulation. Brain MRI shows no cortical diffusion restriction. What does this predict?
A) Poor neurological outcome
B) Good neurological outcome
C) No prognostic value
D) Need for immediate withdrawal of care
Answer: B
Explanation: Evidence from 5 studies consistently suggests that the absence of visible cytotoxic edema, assessed as the absence of cortical diffusion-weighted imaging changes on brain MRI, predicts good neurological outcome with high specificity at ≥72 hours after cardiac arrest 4. The absence of restricted diffusion in cortex or deep gray matter has been shown to have 72-100% sensitivity and 81-95% specificity for favorable neurological outcome 4.
Question 15
In post-cardiac arrest prognostication, what is the recommended timing for brain MRI to assess for cortical diffusion restriction?
A) Within 6 hours
B) 12-24 hours
C) ≥72 hours
D) 7 days
Answer: C
Explanation: The 2023 International Consensus on Cardiopulmonary Resuscitation recommends that brain MRI for prognostication should be performed at ≥72 hours after cardiac arrest 4. Studies show that the absence of cortical diffusion-weighted imaging changes at this timepoint predicts good neurological outcome with high specificity 4.
Question 16
A 72-year-old woman is comatose 24 hours after cardiac arrest. Her GCS motor score is 2. Should this be used alone to predict poor outcome?
A) Yes, it is sufficient for withdrawal of care decisions
B) No, multiple prognostication modalities should be used
C) Yes, but only if confirmed by family
D) No, wait until 7 days post-arrest
Answer: B
Explanation: Any possible withdrawal of life-sustaining therapies in post-cardiac arrest patients should be undertaken only by using several prognostication modalities according to the 2020 CoSTR on the prediction of poor outcome 4. The 2023 guidelines emphasize that no single test should be used in isolation for prognostication 4.
Question 17
A 55-year-old man with medulloblastoma undergoes treatment. On follow-up MRI, the sum of products of perpendicular diameters of measurable lesions has decreased by 60% compared to baseline, sustained for 6 weeks. CSF cytology remains negative. What is the response category?
A) Complete response
B) Partial response
C) Stable disease
D) Progressive disease
Answer: B
Explanation: According to RAPNO guidelines for medulloblastoma, partial response (PR) is defined as ≥50% decrease (compared with baseline) in the sum of the products of perpendicular diameters of all measurable lesions sustained for at least 4 weeks, with no progression of nonmeasurable disease 4. Complete response would require complete disappearance of all disease 4.
Question 18
In medulloblastoma response assessment, how many target lesions should be selected for measurement if multiple measurable lesions are present?
A) All lesions
B) Up to 2 lesions
C) Up to 4 lesions
D) Up to 6 lesions
Answer: C
Explanation: The RAPNO guidelines recommend that if multiple measurable lesions are present, up to 4 target lesions should be selected to follow for response assessment 4. Standard 2-dimensional measurements (largest tumor diameter and its largest perpendicular) should be used 4.
Question 19
A patient with medulloblastoma develops a new enhancing lesion on MRI 2 months after completing radiotherapy. What is the most appropriate next step before declaring progressive disease?
A) Immediately declare progressive disease
B) Confirm by biopsy if suspected to be treatment-related
C) Wait 6 months and repeat imaging
D) Start salvage chemotherapy
Answer: B
Explanation: According to RAPNO guidelines, any new lesions suspected to be treatment-related should be confirmed by biopsy before declaring progressive disease 4. This is important because treatment-related changes (pseudoprogression) can mimic tumor progression on imaging 4.
Question 20
A 35-year-old woman with functional neurological disorder presents with gait abnormality and sensory symptoms. She strongly disagrees with the diagnosis and believes she has multiple sclerosis. Is occupational therapy likely to be beneficial?
A) Yes, equally beneficial regardless of diagnostic acceptance
B) No, strong disagreement with diagnosis makes therapy much less likely to be helpful
C) Yes, but only if family agrees with the diagnosis
D) No, occupational therapy is contraindicated in FND
Answer: B
Explanation: The 2020 consensus recommendations for functional neurological disorder state that where there is strong disagreement about the diagnosis, therapy is much less likely to be helpful 4. Occupational therapy is likely to be successful if the person has some degree of understanding and agreement with the diagnosis, has agreed to the referral, and can identify rehabilitation goals 4.
Question 21
In occupational therapy assessment for functional neurological disorder, which two conceptual models of practice are most commonly used?
A) Biomechanical Model and Rehabilitation Frame of Reference
B) Model of Human Occupation and Canadian Model of Occupational Performance and Engagement
C) Person-Environment-Occupation Model and Ecology of Human Performance
D) Cognitive Behavioral Model and Psychodynamic Frame of Reference
Answer: B
Explanation: The consensus group for FND occupational therapy most commonly uses the Model of Human Occupation and the Canadian Model of Occupational Performance and Engagement 4. These models were favored owing to their links with well-established tools used to guide assessment and intervention with FND 4.
Question 22
A 42-year-old woman with FND is being assessed by occupational therapy. During observation of daily activities, her symptoms show marked variability and distractibility. What should the therapist do?
A) Document but do not discuss with patient
B) Discuss in a supportive way with the patient
C) Refer to psychiatry immediately
D) Discharge from therapy
Answer: B
Explanation: During observation of daily activities in FND assessment, therapists should note distractibility and variability of symptoms so that these can be discussed in a supportive way 4. This observation is part of the comprehensive OT assessment that explores the impact of symptoms on activity engagement 4.
Question 23
A 38-year-old man with progressive external ophthalmoplegia and skeletal myopathy is diagnosed with a TWNK gene mutation. What is the most common phenotype associated with Twinkle-related disorders?
A) Infantile-onset cerebellar ataxia
B) Parkinsonism
C) Primary mitochondrial myopathy
D) Multisystem involvement
Answer: C
Explanation: In the TReDIC multinational cohort study of 189 patients with Twinkle-related disorders, primary mitochondrial myopathy (PMM) was the predominant syndrome, affecting 85.2% of patients 6. The most common features were progressive external ophthalmoplegia (84.7%) and skeletal myopathy (55.6%) 6.
Question 24
In patients with Twinkle-related disorders, what percentage initially present with neuromuscular symptoms?
A) 25%
B) 50%
C) 76.8%
D) 95%
Answer: C
Explanation: Most patients with Twinkle-related disorders (76.8%) presented with neuromuscular symptoms at onset 6. However, by more than 8 years from onset, these proportions shifted to 54.4% neuromuscular, 23.3% CNS, and 23.3% multiorgan features, demonstrating disease progression 6.
Question 25
A 45-year-old woman with Twinkle-related disorder has progressive external ophthalmoplegia. What is the mean age at symptom onset for this condition?
A) 15 years
B) 25 years
C) 40 years
D) 60 years
Answer: C
Explanation: The TReDIC study of 189 patients with Twinkle-related disorders found a mean age at symptom onset of 40.3 years 6. At the time of analysis, 70.4% of patients were alive 6.
Question 26
In Alzheimer's disease neuropathologic assessment, what does the "A" in the ABC score represent?
A) Amyloid angiopathy severity
B) Aβ/amyloid plaque score by Thal method
C) Astrocytic gliosis
D) Atrophy severity
Answer: B
Explanation: In the NIA-Alzheimer's Association ABC scoring system, "A" represents the Aβ/amyloid plaque score, which should be determined by the method of Thal et al. 4. The ABC score combines A (amyloid plaques), B (neurofibrillary tangle stage by Braak), and C (neuritic plaque score by CERAD) 4.
Question 27
A neuropathologic examination shows Braak stage 1 for neurofibrillary tangles, Thal phase 0 for amyloid plaques, and CERAD score 0 for neuritic plaques. What level of AD neuropathologic change does this represent?
A) Not AD
B) Low
C) Intermediate
D) High
Answer: B
Explanation: According to the NIA-Alzheimer's Association guidelines, an ABC score of B1, A0, C0 indicates "Low" AD neuropathologic change 4. Medial temporal lobe neurofibrillary tangles in the absence of significant Aβ or neuritic plaques occurs in older people and may be seen in individuals without cognitive impairment 4.
Question 28
In neuropathologic assessment for Alzheimer's disease, which brain region should be examined for Lewy bodies as a primary (1°) screen?
A) Hippocampus
B) Amygdala
C) Cerebellum
D) Occipital cortex
Answer: B
Explanation: According to the NIA-Alzheimer's Association guidelines, the amygdala should be examined with immunohistochemistry as a primary (1°) screen for Lewy bodies 4. The guidelines recommend screening for Lewy bodies with immunohistochemistry or H&E in brainstem and immunohistochemistry in amygdala, and if positive, then expanding immunohistochemistry for Lewy bodies in brainstem, limbic, and neocortical regions 4.
Question 29
A 70-year-old man with suspected normal-pressure hydrocephalus undergoes shunt surgery with an open valve setting. At 3 months, what is the expected mean improvement in Tinetti scale score compared to placebo?
A) 0.5 points
B) 1.5 points
C) 2.4 points
D) 5.0 points
Answer: C
Explanation: In the PENS trial, patients with open-shunt valves showed a mean improvement of 2.9 points on the Tinetti scale at 3 months, compared to 0.5 points in the placebo group, resulting in a treatment difference of 2.4 points (P=0.003) 1. The Tinetti scale ranges from 0 to 28, with lower scores indicating worse gait and balance 1.
Question 30
In the PENS trial for normal-pressure hydrocephalus, which adverse event was more common in the open-shunt group compared to placebo?
A) Falls
B) Cerebral bleeding
C) Subdural bleeding
D) Seizures
Answer: C
Explanation: In the PENS trial, more participants in the open-shunt group had subdural bleeding (12% vs. 2%) and positional headaches (59% vs. 28%) compared to placebo 1. Conversely, more participants in the placebo group reported falls (46% vs. 24%), while cerebral bleeding was equal in both groups (2%) 1.
Question 31
A 68-year-old man with type 2 diabetes and atherosclerotic cardiovascular disease is started on tirzepatide. What is the mechanism of action?
A) GLP-1 receptor agonist only
B) DPP-4 inhibitor
C) Dual GLP-1 and GIP receptor agonist
D) SGLT-2 inhibitor
Answer: C
Explanation: Tirzepatide is a dual incretin agonist of the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors 7. This dual mechanism distinguishes it from single GLP-1 receptor agonists like dulaglutide 7.
Question 32
In the SURPASS-CVOT trial comparing tirzepatide to dulaglutide, what was the hazard ratio for the primary cardiovascular endpoint?
A) 0.75 (95.3% CI, 0.65-0.85)
B) 0.92 (95.3% CI, 0.83-1.01)
C) 1.05 (95.3% CI, 0.95-1.15)
D) 1.20 (95.3% CI, 1.10-1.30)
Answer: B
Explanation: In the SURPASS-CVOT trial, the primary endpoint (composite of death from cardiovascular causes, myocardial infarction, or stroke) occurred in 12.2% of the tirzepatide group and 13.1% of the dulaglutide group, with a hazard ratio of 0.92 (95.3% CI, 0.83-1.01; P=0.003 for noninferiority; P=0.09 for superiority) 7. Tirzepatide met noninferiority but not superiority criteria 7.
Question 33
A 52-year-old woman with atrial fibrillation receives abelacimab 150 mg monthly. At 3 months, what is the expected median reduction in free factor XI levels?
A) 50% (IQR 40-60%)
B) 75% (IQR 65-85%)
C) 90% (IQR 85-95%)
D) 99% (IQR 98-99%)
Answer: D
Explanation: In the AZALEA-TIMI 71 trial, at 3 months, the median reduction in free factor XI levels with abelacimab at a dose of 150 mg was 99% (interquartile range, 98 to 99) 2. With the 90-mg dose, the median reduction was 97% (IQR 51-99) 2.
Question 34
In patients with ALS, what is the recommended frequency for dysphagia screening?
A) At diagnosis only
B) Every month
C) Every 3 months
D) Every 6 months
Answer: C
Explanation: The American Speech-Language-Hearing Association recommends dysphagia screening at diagnosis and every 3 months thereafter as part of comprehensive evaluation in ALS patients 5. This regular screening is important because swallowing abnormalities can occur even without bulbar symptoms, and early detection prevents aspiration pneumonia 5.
Question 35
A 50-year-old man with suspected ALS has normal EMG and NCV studies. What is the likelihood that he has ALS?
A) Very high, clinical diagnosis is sufficient
B) Very low, EMG/NCV are mandatory for diagnosis
C) Moderate, depends on clinical features
D) Cannot be determined
Answer: B
Explanation: The American Academy of Neurology recommends EMG and nerve conduction velocity (NCV) studies as mandatory for detecting lower motor neuron degeneration and distinguishing ALS from other conditions 5. Normal EMG and NCV studies make the diagnosis of ALS extremely unlikely 5.
Question 36
In a 6-year-old boy with developmental delay and a family history suggestive of X-linked disorder, what additional genetic test should be considered beyond CMA and Fragile X?
A) MECP2 sequencing
B) X-linked ID panel and high-density X-CMA
C) Whole genome sequencing
D) Mitochondrial DNA testing
Answer: B
Explanation: According to the 2014 AAP guidelines for GDD/ID, if family history is suggestive of X-linked disorder, send X-linked ID panel and high-density X-CMA 4. Additionally, consider testing for X-inactivation skewing in the mother of the proband 4.
Question 37
A 2-year-old girl with global developmental delay has normal CMA and Fragile X testing. The 2021 ACMG guidelines recommend which test as first- or second-tier?
A) Karyotype
B) Metabolic screening
C) Exome sequencing (ES) or whole genome sequencing (WGS)
D) MECP2 sequencing
Answer: C
Explanation: The 2021 ACMG guidelines state that ES/WGS should be a first- or second-tier test in all patients with unexplained DD/ID or congenital anomalies 4. This represents an evolution in genetic testing recommendations, recognizing the high diagnostic yield of these comprehensive genomic tests 4.
Question 38
In transcranial direct current stimulation (tDCS) for addiction, what is the most common cathode placement when the anode is on the right DLPFC?
A) Right supraorbital
B) Left DLPFC
C) Occipital region
D) Motor cortex
Answer: B
Explanation: In tDCS studies targeting the right DLPFC with anodal stimulation, the cathode was most commonly placed on the left DLPFC (15 out of 17 studies) 4. Other cathode placements included supraorbital (1 study) and occipital region (1 study) 4.
Question 39
A patient with medulloblastoma has complete disappearance of all enhancing disease on brain MRI, but CSF cytology shows persistent tumor cells. What is the response category?
A) Complete response
B) Partial response
C) Stable disease
D) Progressive disease
Answer: D
Explanation: According to RAPNO guidelines for medulloblastoma, complete response requires complete disappearance of all disease on MRI AND, if tumor cells were present in CSF at baseline, they must be negative 4. The presence of previously absent tumor cells in CSF now constitutes progressive disease 4.
Question 40
In medulloblastoma response assessment, what percentage increase in the sum of products of perpendicular diameters defines progressive disease?
A) ≥10%
B) ≥15%
C) ≥25%
D) ≥50%
Answer: C
Explanation: According to RAPNO guidelines, progressive disease is defined as ≥25% increase (compared with smallest measurement at any time point) in the sum of the products of perpendicular diameters of all measurable lesions 4. This also includes significant progression of nonmeasurable disease not attributed to prior therapy or any new tumor 4.
Question 41
A 48-year-old woman with functional neurological disorder is starting occupational therapy. What is the core focus of initial OT intervention?
A) Provision of aids and adaptations
B) Improving function through guided activity practice
C) Psychological counseling
D) Medication management
Answer: B
Explanation: The consensus group identified that core OT interventions for FND include physical rehabilitation through guided activity practice, practical management of pain and fatigue, support to address mental health problems, and support to reduce dependency and optimize independence 4. Patients should understand that the initial focus of OT is to improve function and therefore is unlikely to include provision of aids and adaptations 4.
Question 42
In Twinkle-related disorders, what percentage of patients have hearing loss?
A) 5%
B) 17.5%
C) 35%
D) 55%
Answer: B
Explanation: In the TReDIC multinational cohort study, hearing loss was present in 17.5% of patients with Twinkle-related disorders 6. The most common features were progressive external ophthalmoplegia (84.7%) and skeletal myopathy (55.6%), followed by hearing loss (17.5%) and psychiatric symptoms (15.3%) 6.
Question 43
A 65-year-old man is comatose 5 days after cardiac arrest. Brain MRI shows no DWI or FLAIR lesions in the cortex. What is the approximate sensitivity of this finding for favorable neurological outcome?
A) 50%
B) 65%
C) 78%
D) 92%
Answer: C
Explanation: According to the study by Mlynash et al., no DWI or FLAIR lesions in cortex at ≤8 days after cardiac arrest had 77.8% sensitivity (95% CI 52.4-93.6%) and 80.0% specificity (95% CI 51.9-95.7%) for favorable neurological outcome 4. This represents one of several MRI findings that can predict good outcome 4.
Question 44
In neuropathologic assessment for Alzheimer's disease, how many brain regions are recommended for enumeration of microvascular lesions?
A) 2
B) 4
C) 6
D) 12
Answer: C
Explanation: The NIA-Alzheimer's Association guidelines recommend that enumeration of microvascular lesions (MVLs) for clinico-pathologic correlations of cognitive impairment and dementia be limited to six regions 4. These regions are specifically designated in the sampling protocol 4.
Question 45
A 72-year-old woman with suspected normal-pressure hydrocephalus undergoes shunt surgery. At 3 months, did the PENS trial show improvement in cognition (MoCA score)?
A) Yes, significant improvement (P<0.001)
B) Yes, moderate improvement (P=0.02)
C) No significant improvement
D) Significant worsening
Answer: C
Explanation: In the PENS trial, shunting resulted in significant improvements at 3 months in gait velocity and Tinetti scale score but NOT in the Montreal Cognitive Assessment (MoCA) score (1.3 points vs. 0.3 points in placebo, not statistically significant) or the Overactive Bladder Questionnaire score 1. The primary benefit was in motor function, not cognition or incontinence 1.
Question 46
In the default mode network (DMN), what brain structure shows characteristic hypometabolism on FDG-PET in Alzheimer's disease?
A) Hippocampus
B) Posterior cingulate cortex and precuneus
C) Frontal pole
D) Occipital cortex
Answer: B
Explanation: FDG-PET demonstrates characteristic patterns of hypometabolism in DMN regions, particularly the posterior cingulate cortex and precuneus, in Alzheimer's disease with sensitivity up to 95% and specificity up to 73% 8. This pattern is highly characteristic of Alzheimer's disease 8.
Question 47
A 60-year-old stroke survivor has persistent attention deficits. Resting-state fMRI shows loss of anticorrelation between the DMN and dorsal attention network. What does this predict?
A) Good recovery
B) Paradoxical attention deficits with intrusive self-referential thoughts
C) No clinical significance
D) Need for immediate neurosurgery
Answer: B
Explanation: In stroke survivors, loss of the normal anticorrelation between the default mode network (DMN) and task-positive networks (e.g., dorsal attention network) produces paradoxical attention deficits, characterized by intrusive self-referential thoughts that interfere with external task performance 8. This represents a failure of normal network segregation 8.
Question 48
In patients with ALS, what is the sensitivity and specificity of the Volume-Viscosity Swallow Test (V-VST) for detecting dysphagia?
A) 70% sensitivity, 60% specificity
B) 80% sensitivity, 70% specificity
C) 92% sensitivity, 80% specificity
D) 95% sensitivity, 90% specificity
Answer: C
Explanation: The American College of Gastroenterology recommends the Volume-Viscosity Swallow Test (V-VST), which demonstrates 92% sensitivity and 80% specificity for detecting dysphagia in ALS patients 5. This makes it a highly accurate bedside screening tool 5.
Question 49
A 35-year-old man with neurofibromatosis type 2 has bilateral vestibular schwannomas. According to consensus recommendations, which patient population is most suitable for drug clinical trials?
A) Patients with tumors being conservatively followed
B) Patients who have failed radiosurgery
C) Patients with multiple tumors who cannot undergo further surgery
D) Asymptomatic gene carriers
Answer: C
Explanation: According to the 2009 consensus recommendations for NF2 clinical trials, patients with multiple tumors who cannot undergo further surgery offer a compelling study group and one in desperate need of options 4. These trials are likely to be efficient if response is used as an endpoint, and drug treatment could be offered in adjunct to surgery or if surgery has been exhausted 4.
Question 50
In NF2 clinical trials, what is the recommended primary outcome measure for phase II studies?
A) Quality of life measures
B) Hearing change
C) Tumor shrinkage
D) Progression-free survival
Answer: C
Explanation: According to the 2009 consensus recommendations for NF2 clinical trials, for phase II studies, tumor shrinkage should be the end point used due to study power concerns 4. Other outcome measures include loss of T2 signal, hearing change (4-frequency pure-tone average >5 dB change or 15% difference in speech discrimination), and quality of life measures 4.