Development of a subject-specific guide system for Low-Intensity Focused Ultrasound (LIFU) brain stimulation.

Low-Intensity Focused Ultrasound (LIFU) has recently been considered as a promising neuromodulation technique because it can noninvasively stimulate the brain with a high spatial resolution. As spatial resolution is improved, there is a growing demand for developing more accurate and convenient guide systems. Therefore, in the present study, we have developed and prototyped a 3D printed wearable subject-specific helmet for LIFU stimulation that is guaranteed to be accurate. The spatial relationship between the target position and the full-width at half-maximum (FWHM) of acoustic pressure of the transducer, i.e. focal volume, was compared using the conventional image-guided navigation system. According to the distribution of positional errors, the target position was located well within the focal volume.