A Case of Psychogenic Dizziness Mimicking Vestibular Epilepsy
A 28-year-old man presented to our clinic three days after his first episode of vertigo. The patient was suffering from frequent episodes of severe spinning vertigo with mild nausea; each episode lasted for a few minutes. The patient complained of a severe whirling sensation with a clockwise direction during the ictus, and experienced a dull headache after the ictus. The patient reported that he did not suffer from agoraphobia, panic symptoms, or any recent stressful conditions. Nor was the ictus accompanied by ear symptoms, such as tinnitus, hearing loss, or aural fullness, and there were no other symptoms, such as paresthesia, motor deficit, or visual disturbances, including field defect, metamorphopsia, or color change. His symptom was not predictable and occurred without any position change. The patient did not lose consciousness during the onset of the symptom, and his family members had not witnessed any eyeball deviation or head turning during the episodes. The patient had no history of motion sickness or migraine. However, he had undergone an operation in the left cerebral hemisphere for the treatment of Moyamoya disease (encephaloduroarteriosynangiosis, EDAS) 3 years ago. Brain MRI revealed the presence of an osteoplastic craniotomy scar in the left lateral convexity (). No nystagmus was observed and his symptoms were not evoked by the hyperventilation maneuver. The patient showed bilaterally symmetrical saccade and smooth pursuit. A cerebellar function test was normal and a caloric test and audiometry showed normal responses. We assumed that the ictus was a manifestation of vestibular epilepsy. Therefore, the patient was admitted to the Epilepsy Monitoring Unit (EMU). He was monitored continuously for 24 hours a day with video and computerized EEG equipment. However, the episodes of vertigo were not accompanied by any significant EEG changes, such as sharp waves and spikes. Therefore, we suspected that the episodes might be psychogenic dizziness. The patient was responsive to benzodiazepine medication and psychological encouragement.