Emergence of complex, involuntary movements after gamma knife radiosurgery for essential tremor

Gamma knife radiosurgery is generally considered a safer alternative to traditional pallidotomy or thalamotomy. We report the case of a 59‐year‐old patient with essential tremor who developed a complex, disabling movement disorder following gamma knife thalamotomy. This case illustrates the need for long‐term follow‐up to fully evaluate the potential for complications following radiosurgery. © 2001 Movement Disorder Society.