Correlative high-resolution MR-anatomic study of sciatic, ulnar, and proper palmar digital nerve

Aim of this study was o evaluate the effectiveness of high-resolution MR imaging in demonstrating the anatomic structure of peripheral nerves of different diameter and composition. The dissected sciatic, ulnar, and proper palmar digital nerve of fresh cadavers were imaged at pre-selected landmarks on a 3T MR scanner. The nerves were then embedded in formalin, sliced, stained, and microscopically analyzed. The size, shape, and signal intensity of the sheath and axonal structures in the nerves at the landmarks were identified in MR images by comparison with histologic sections. The fascicles were clearly distinguished and counted in all specimens with MR imaging and showed only small differences from the histologic evaluation. High resolution MR imaging has the potential to visualize the fascicular structure in nerves of all sizes, which may be helpful in the preoperative assessment.