A 3D DIGITAL MAP OF RAT-BRAIN

A three dimensional (3D) computerized map of rat brain anatomy created with digital imaging techniques is described. Six male Sprague-Dawley rats, weighing 270-320 g, were used in the generation of this atlas. Their heads were frozen, and closely spaced cryosectional images were digitally captured. Each serial data set was organized into a digital volume, reoriented into a flat skull position, and brought into regist er with each other. A volume representative of the group following reg istration was chosen based on its anatomic correspondence with the oth er specimens as measured by image correlation coefficients and landmar k matching. Mean positions of lambda, bregma, and the interaural plane of the group within the common coordinate system were used to transfo rm the representative volume into a 3D map of rat neuroanatomy. Images reconstructed from this 3D map are available to the public via Intern et with an anonymous file transfer protocol (FTP) and World Wide Web. A complete description of the digital map is provided in a comprehensi ve set of sagittal planes (up to 0.031 mm spacing) containing stereota xic reference grids. Sets of coronal and horizontal planes, resampled at the same increment, also are included. Specific anatomic features a re identified in a second collection of images. Stylized anatomic boun daries and structural labels were incorporated into selected orthogona l planes. Electronic sharing and interactive use are benefits afforded by a digital format, but the foremost advantage of this 3D map is its whole brain integrated representation of rat in situ neuroanatomy.