MD - Doctor of Medicine Central Nervous System Disorders Questions and Answers

Question 1

A 68-year-old male presents with a resting tremor in his right hand, bradykinesia, and rigidity.
His symptoms have progressed slowly over the past two years.
Which of the following is the primary pathophysiological mechanism responsible for this patient's motor symptoms?

Accepted Answer

Loss of dopaminergic neurons in the substantia nigra pars compacta

Answer

Degeneration of cholinergic neurons in the nucleus basalis of Meynert

Answer

Autoimmune demyelination of oligodendrocytes in the central nervous system

Answer

Expansion of CAG trinucleotide repeats in the huntingtin gene

Question 2

A 29-year-old female presents with an episode of unilateral vision loss and pain with eye movement that resolved over several weeks. Six months later, she develops numbness and tingling in her left leg. An MRI of the brain reveals multiple periventricular white matter lesions. A lumbar puncture is performed. Which cerebrospinal fluid (CSF) finding would be most supportive of a diagnosis of multiple sclerosis?

Accepted Answer

Presence of two or more IgG oligoclonal bands not present in the serum

Answer

Elevated protein with a normal cell count (albuminocytologic dissociation)

Answer

Low glucose, high protein, and marked neutrophilic pleocytosis

Answer

Xanthochromia and a high red blood cell count

Question 3

A 75-year-old man is brought to the emergency department 90 minutes after the sudden onset of left-sided weakness and facial droop. A non-contrast head CT scan shows no evidence of intracranial hemorrhage. His blood pressure is 170/95 mmHg. What is the most appropriate immediate intervention?

Accepted Answer

Administration of intravenous alteplase (tPA)

Answer

Immediate administration of high-dose aspirin

Answer

Urgent neurosurgical consultation for hematoma evacuation

Answer

Observation and supportive care with repeat CT in 24 hours

Question 4

Which of the following is the fundamental pathogenic mechanism underlying Myasthenia Gravis?

Accepted Answer

Antibody-mediated destruction of postsynaptic acetylcholine receptors

Answer

Degeneration of upper and lower motor neurons

Answer

T-cell mediated attack on the myelin sheath of peripheral nerves

Answer

Deposition of alpha-synuclein aggregates in motor neurons

Question 5

A 45-year-old man with a history of alcohol abuse is brought to the emergency department. He has been continuously seizing for 10 minutes despite pre-hospital administration of an IM benzodiazepine. In the ED, he remains unresponsive and continues to have generalized tonic-clonic seizure activity. After securing the airway and obtaining IV access, which medication should be administered first?

Accepted Answer

An intravenous bolus of lorazepam

Answer

A loading dose of oral phenytoin

Answer

An intravenous bolus of propofol

Answer

An intravenous infusion of phenobarbital

Question 6

A pathologist is examining brain tissue from a patient who had severe dementia. The microscopic examination reveals numerous extracellular neuritic plaques and intracellular neurofibrillary tangles, particularly in the hippocampus and neocortex. These findings are the classic neuropathological hallmarks of which condition?

Accepted Answer

Alzheimer's Disease

Answer

Lewy Body Dementia

Answer

Creutzfeldt-Jakob Disease

Answer

Huntington's Disease