A Case of Bilateral Auricular Dystonia With Both Sensory Trick and Reverse Sensory Trick Successfully Treated With Botulinum Toxin Therapy

The patient was a 39-year-old male who presented to our hospital with a 15-year history of sustained involuntary movements of both auricles. A phenomenon suspected to be a sensory trick was observed, in which pressing on the frontal region above the eyebrows ceased the involuntary movements and was accompanied by compensatory contraction of the frontalis muscle. It was considered that this sensory trick, induced by pressure stimulation, led to the simultaneous occurrence of two distinct behaviors: the improvement of auricular dystonia and the emergence of involuntary contraction of the frontalis muscle. Botulinum toxin A was administered to both the auricular muscles and the frontalis muscle, resulting in favorable control of the symptoms. Reports of bilateral auricular dystonia are exceedingly rare. Moreover, the concurrent appearance of two types of sensory tricks - one alleviating dystonia and the other exacerbating it - is also uncommon. When administering botulinum toxin A injection in such cases, it may be beneficial to consider not only for the primary dystonia but also for the sites where reverse sensory tricks manifest, potentially achieving better outcomes.