Incisionless MR-guided focused ultrasound: technical considerations and current therapeutic approaches in psychiatric disorders

ABSTRACT

Introduction

MR-guided focused ultrasound operating at higher intensities have been reported to effectively and precisely ablate deeper brain structures like the basal ganglia or the thalamic nuclei for the treatment of refractory movement disorders, neuropathic pain and most recently neuropsychiatric disorders, while low-intensity focused ultrasound represents an approach promoting mechanical blood-brain-barrier opening and neuromodulation. This narrative review summarizes the technical development and the therapeutic potential of incisionless MRgFUS in order to treat neuropsychiatric disorders.

Areas covered

A narrative review of clinical trials assessing the safety and efficacy of MRgFUS. A literature review was performed using the following search terms: MR-guided focused ultrasound, psychiatric disorders, noninvasive and invasive brain modulation/stimulation techniques.

Expert opinion

MRgFUS ablation is under clinical investigation (unblinded study design) for obsessive-compulsive disorders (OCDs) [capsulotomy; ALIC] and depression/anxiety disorders [capsulotomy] and has demonstrated an improvement in OCD and depression, although of preliminary character. Low-intensity ultrasound applications have been explored in Alzheimer´s disease (phase 1 study) and healthy subjects.

Currently, limited evidence hinders comparison and selection between MRgFUS and noninvasive/invasive brain modulation therapies. However, comparative, sham-controlled trials are needed to reexamine the preliminary findings for the treatment of psychiatric disorders.

KEYWORDS:

• Noninvasive MR-guided focused ultrasound
• cingulotomy
• capsulotomy
• deep brain stimulation
• depression
• obsessive-compulsive disorder
• radiosurgery
• outcome measures

Article highlights

• Non-invasive ultrsaound ablation (MRgFUS) represents a novel option for lesioning therapy in psychiatric disorders

• Depression and obssessive-compulsive disorder are currently trialed in ongoing studies

• Depending on energy intensity, non-ablative MRgFUS has the potential to modulate multifocal brain circiuts

• Comparative studies including other brain stimulation/modulation approaches are needed in order to determine its therapeutic potential

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.