Purpose: To determine whether the four subdivisions of Ammon's horn and six layers of CA1 seen histologically can be demonstrated with MR imaging.
Methods: Specimens of cadaver brains were imaged in a 3.0-T MR imager with a 3.0-cm solenoid coil. The specimens were sectioned, stained, and examined histologically. On anatomic sections, the four subdivisions of Ammon's horn and six layers of CA1 were identified. The MR images were then compared with the anatomic sections.
Results: Using geographic characteristics, we identified the four subdivisions of Ammon's horn. In CA1, the six layers could be identified by variations in signal intensity, width, and location.
Conclusion: This study suggests that, with MR imaging of sufficiently high resolution, the internal architecture of Ammon's horn may be identified.