Abstract: Objective To investigate the morphology and relationships with the adjacent structures in the pineal region on the thin sections and to provide anatomic data for imaging diagnosis and surgical treatment of diseases in this region. Methods By CT and MRI examination, one normal head specimen was selected for this study. Using the computerized freezing milling technique, the specimen was sliced from anterior to posterior. The EM>in vivo/EM> MR images were obtained from ten normal Chinese male adult volunteers using a 3.0 T GE scanner. The base lines of the sectioning and the MR scan were perpendicular to the AC-PC line. Then primary sections were contrasted with the corresponding MR images. Results By the appearance of the pineal peduncle and the disappearance of the pineal gland, the pineal region could be divided into three parts from anterior to posterior, and the shape changed from an inverted triangle to a trapezoid and a triangle gradually. The first interspace was getting wider in the anterior and middle parts of the pineal region, while in the posterior part of the pineal region, it was getting narrower and disappeared finally. From anterior to posterior, the bilateral internal cerebral veins were always in the midline of the pineal region and descended gradually.Conclusion By the computerized freezing milling technique, the anatomic details and adjacent relationships of the pineal region could be exhibited clearly in the thin serial sections, which could help the imaging diagnosis and surgical treatments for minute diseases in this region.

Key words: Pineal region, Thin sectional anatomy, Computerized freezing milling technique, MRI, Human