MCCQE Neurological Disorders 3

Question 1

A 55-year-old diabetic man presents with foot drop and inability to evert his foot. There is sensory loss over the dorsum of the foot. Which nerve is most likely injured?

Accepted Answer

Common peroneal nerve

Answer

Common peroneal nerve injury causes foot drop (weakness of dorsiflexion and eversion) and sensory loss over the dorsum of the foot and lateral leg.

Question 2

A 19-year-old man has brief staring spells lasting 5-10 seconds with eyelid fluttering, occurring multiple times daily. His mother says he had similar episodes as a child. EEG shows 3 Hz spike-and-wave during hyperventilation. What is the most likely diagnosis?

Accepted Answer

Absence epilepsy

Answer

Absence epilepsy is characterized by brief staring spells with eyelid fluttering, 3 Hz spike-and-wave on EEG, and provocation by hyperventilation.

Question 3

A 75-year-old man presents with fluctuating cognition, visual hallucinations of animals and people, and parkinsonian features. He is very sensitive to haloperidol. What is the most likely diagnosis?

Accepted Answer

Lewy body dementia

Answer

Lewy body dementia is characterized by fluctuating cognition, recurrent visual hallucinations, parkinsonism, and severe neuroleptic sensitivity, distinguishing it from other dementias.

Question 4

A 48-year-old man presents with sharp stabbing facial pain in the distribution of V2 and V3, triggered by chewing and touching his face. The pain lasts seconds. Neurological examination is normal. What is the most appropriate first-line treatment?

Accepted Answer

Carbamazepine

Answer

Carbamazepine is the first-line treatment for trigeminal neuralgia, with the highest level of evidence for reducing the frequency and severity of lancinating facial pain.

Question 5

A 32-year-old woman presents with sudden-onset weakness and areflexia in all four limbs after recovering from a respiratory illness. She requires mechanical ventilation. Which monitoring parameter is most important in this condition?

Accepted Answer

Forced vital capacity (FVC)

Answer

In Guillain-Barré syndrome, serial FVC monitoring is critical because respiratory muscle weakness can lead to respiratory failure; intubation is indicated when FVC falls below 15-20 mL/kg.

(MCCQE) Medical Council of Canada Qualifying Examination Practice Test

(MCCQE) Medical Council of Canada Qualifying Examination Practice Test

MCCQE Neurological Disorders 3