Treatment of Functional (Psychogenic) Tremor with a Mirror Box: A Case Report

An 18 year old right handed woman presented to the Muhammad Ali Parkinson Center (MAPC) at the Barrow Neurological Institute (BNI) with a marked tremor of her right hand. The tremor was disabling, preventing or hindering her from performing her activities of daily living (ADLs). An evaluation including a detailed neurological examination, brain magnetic resonance imaging (MRI) and a dopamine transporter scan (DATscan) was unrevealing. She did not have Parkinson disease (PD), or Essential Tremor (ET), or dystonic or taskspecific tremor. She was diagnosed with a functional (psychogenic) tremor. She denied being anxious or depressed. There was no obvious secondary gain from her tremor: she was not working, was not claiming disability, and was living at home with her parents. She refused to accept a psychological or psychiatrist evaluation. She was referred for occupational therapy with a “mirror box”. A “mirror box” is a box with two mirrors in the center one facing each way originally invented to alleviate phantom limb pain by “tricking” the patient into believing the amputated limb is whole, moving, and painless. It has subsequently been adapted to treat a number of functional disorders. In our patientthe “mirror box” relieved her tremor. Scheub T and Lieberman A* Department of Neurology, Barrow Neurological Institute, USA Lieberman A, et al. Annals of Clinical Case Reports Neurology Remedy Publications LLC., | http://anncaserep.com/ 2016 | Volume 1 | Article 1054 2 Brain MRI was normal. A DATscan revealed no dopamine depletion. Neuropsychological revealed no obvious issues. She was neither unduly anxious nor depressed. There was no obvious secondary gain: she was not working, was not claiming disability, and was living with her parents at home without obvious financial pressures. She was not on any drugs that could produce tremor. The patient was referred for occupational therapy for what she said was an incapacitating tremor of her right dominant hand. The main intervention was the use of a mirror box. During mirror box therapy her left upper limb which had no tremor was reflected as her right upper arm, while her right upper limb was outside the box and invisible to the patient. In this setting the absence of tremor in her left upper limb was seen, by the patient as an absence of tremor in her right upper limb and the tremor in her right upper limb (held outside the box) decreased in amplitude at rest, on sustention and during action. The patient was instructed on how to use the vanity mirror in her home to have her left nontrembling upper limb reflected as her right in various positions. This maneuver over several days resulted in the tremor in her right upper limb disappearing.