A man in his 30's presented with dizziness, attributed to anxiety and panic. Hearing and other vestibular testing was entirely normal. However, VEMP testing was positive.
|Large oVEMP response in patient with dizziness attributed to anxiety|
|Low threshold cVEMP response in patient with dizziness attributed to anxiety|
The cVEMP test had thresholds down to 55 on the left, and 65 on the right. The 55 dB threshold is very low.
The temporal bone CT scan was clearly negative for SCD.
So overall, we have abnormal VEMPs in a person with dizziness and no other physical findings or inner ear testing abnormalities. He does not have SCD (superior canal dehiscence) although his physiological testing is far into the abnormal range (about 99th percentile). We speculate that this man's dizziness is due to his excessive vestibular sensitivity -- but have no proof.
Why does he have this excessive sensitivity -- it is not a technical problem as he had two different types of VEMPs with excessive sensitivity.
So basically, nothing fits. This happens more often than I would like in clinical work, and presumably reflects my or the field's lack of knowledge.
Should these non-invasive tests (VEMPs) be done in every undiagnosed dizzy patient ? We are somewhat supportive of this idea, although of course, not "every" patient.