Fiber Tractography Analysis Applied to Transcranial MR-guided Focused Ultrasound Surgery (TcMRgFUS)

Abstract

　Transcranial MR-guided focused ultrasound surgery (TcMRgFUS) is recognized as a minimally invasive treatment method for essential tremor (ET), a condition characterized by involuntary motor disturbances. The target region for treating ET is the ventral intermediate (Vim) nucleus of the thalamus, which is surrounded by the ventral caudal nuclei (Vc) and the pyramidal tract (PT).

　While an indirect methodology based on the anatomical atlas and anterior commissure-posterior commissure (AC-PC) line is commonly used for TcMRgFUS targeting, it may not always provide adequate precision due to individual variations in nucleus localization.

　A direct approach utilizing diffusion tensor imaging (DTI) has been proposed to achieve highly accurate targeting. However, the visualization efficacy of fiber tracts varies depending on the algorithm of the analysis used. The generalized q-sampling imaging (GQI) algorithm is reputed to outperform the DTI algorithm in terms of accuracy.

　Leveraging the GQI-based fiber tractography for TcMRgFUS targeting holds promise for providing exceptionally precise treatment outcomes, which is crucial for enhancing the overall efficacy of the procedure.