PLAB-0266

A 22-year-old male presented to the OPD with a complaint of ringing in the ears and impaired hearing with occasional vertigo. On examination, there was slight drooping of the patient’s mouth to the right side. When Weber test was performed, the patient heard a fainter sound in the right ear compared to the left. Absolute bone conduction test revealed that bone conduction was reduced in the right ear. Which of the following would be the most appropriate investigation to be ordered in this case?