Current and future uses of transcranial focused ultrasound in neurosurgery.

Focused ultrasound (FUS) produces a region of high intensity at the focal zone of the beam but with minimal effects at adjacent areas, allowing the sonication of deep targets throughout the body. Despite early obstacles to transmitting ultrasound energy through the skull, recent advances in ultrasound technology, software, and real-time monitoring have resulted in a renewed interest in the clinical applications of transcranial FUS. Following extensive pre-clinical studies, ultrasound-induced thermal ablation has been approved by several countries for the treatment of essential tremor, Parkinson's disease, obsessive-compulsive disorder, depression, and neuropathic pain. Ongoing clinical trials involving patients with brain tumors, Alzheimer's disease, or epilepsy, and pre-clinical work involving stroke and hydrocephalus have the potential to significantly expand the possible indications for transcranial FUS in the future.