Treatment for Vocal Tremor

Vocal tremor is characterized by a rhythmic undulating vocal quality whenever talking, much akin to vibrato that can not be turned off. In the past, it was felt that use of botulinum toxin type A (botox) to treat vocal tremor was not possible nor realistic given the multiple muscle groups involved. This is in contrast to dystonias of the voice (i.e., spasmodic dysphonia) where only one muscle group is involved and is readily and easily treated with botox injections to the affected vocal cord muscle.

However over the past few years, several research papers have been produced that show that botox CAN alleviate (though not eliminate) vocal tremor both objectively and subjectively, though more than one site may need to be injected in order to produce vocal tremor relief. Such muscle sites include thyroarytenoid muscle, ventricularis muscle, lateral cricoarytenoid muscle, interarytenoid muscle, cricothyroid muscle, and strap muscles.

All these muscle sites are easily accessible either via, endoscopic guidance and/or EMG guidance alone. Indeed, physicians who already perform botox injections for spasmodic dysphonia should also be able to inject all the other muscle groups just as easily. [watch video]

Typically, "horizontal" vocal tremor is treated with thyroarytenoid, ventricularis, interarytenoid, and/or lateral cricoarytenoid muscle botox injections.

"Vertical" vocal tremor is treated with strap muscle botox injections.

Dosages are similar to that given to treat spasmodic dysphonia.

SO... for patients suffering from vocal tremor who do not respond well to oral medications (propranolol, primidone), consider botox injections!

Be aware that botox injections to treat vocal tremor may not be covered by insurance.

References:
A new paradigm for the management of essential vocal tremor with botulinum toxin. Laryngoscope. 2013 Apr 1. doi: 10.1002/lary.24073. [Epub ahead of print]

Botulinum toxin type A for treating voice tremor. Arch Neurol. 2004 Sep;61(9):1416-20.

Botulinum toxin for essential tremor of the voice with multiple anatomical sites of tremor: a crossover design study of unilateral versus bilateral injection. Laryngoscope. 2000 Aug;110(8):1366-74.

Tremor laryngeal dystonia: treatment of the lateral cricoarytenoid muscle. Ann Otol Rhinol Laryngol. 2004 May;113(5):349-55.