Abstract
Neuroimaging in the human brainstem presents multiple challenges. With its small size, deep location, and distance from radiofrequency coils used for signal transmission and reception, the brainstem suffers from reduced signal-to-noise compared to cortical structures. While the increased signal provided by ultra-high field (UHF) MRI can be leveraged to improve image resolution and aid localization of small brainstem nuclei, scanning protocols require careful optimization to make the best use of these advantages. Additionally, major challenges remain regarding signal dropout and distortion, as well as the strong influence of physiological noise of cardiac and respiratory origin. Therefore, while UHF allows for more detailed investigation of the human brainstem in vivo, consideration must be given to the unique (or sometimes exacerbated) obstacles that may be encountered when moving to higher fields.