High-frequency stimulation of the subthalamic nucleus (STN) is a widely performed method to treat advanced Parkinson disease. Due to the limitations of current imaging techniques, the 3D microanatomy of the STN and its surrounding structures in the mesencephalon are not well known. Using images they obtained using a 9.4-tesla magnetic resonance (MR) imaging unit, the authors developed a 3D reconstruction of the STN and its immediate surroundings. During the postmortem investigation of a human brain, a sample of tissue in the area around the STN was isolated. This brain tissue was scanned in the three orthogonal planes at 1-mm slice thickness. The images generated were compared with photographs of conventionally stained brain tissue slices in different neuroanatomical books, and a 3D reconstruction was made. High-field MR imaging is an appropriate method for visualizing the microanatomy of the STN and its surroundings. The images allow an optimal analysis of the microenvironment of the STN in the three orthogonal planes and can be used for 3D reconstructions of this area with possible clinical applications in the future.