Question

A 54-year-old man with a history of chronic hyponatremia develops sudden-onset quadriparesis after rapid sodium correction. Which investigation is most appropriate to confirm the diagnosis?

• A. Brainstem evoked potential
• B. Electroencephalogram (EEG)
• C. MRI of the brain
• D. Nerve conduction studies

Hint:

Rapid correction of chronic hyponatremia can cause central pontine myelinolysis; confirm with MRI brain.

Answer 1

The Correct Option is C

Concept: Rapid correction of chronic hyponatremia can cause osmotic demyelination syndrome, classically central pontine myelinolysis. MRI brain is the investigation of choice for confirmation.

Step 1: Identify the trigger.
The patient had: \[ \text{Chronic hyponatremia} \] followed by rapid sodium correction.

Step 2: Identify clinical consequence.
Sudden quadriparesis after rapid correction suggests: \[ \text{Osmotic demyelination syndrome} \]

Step 3: Choose confirmatory investigation.
The most appropriate investigation is: \[ \text{MRI brain} \]