Three-dimensional representation and analysis of brain energy metabolism

Quantitative autoradiography of brain glucose metabolism has been combined with digital image processing to represent the brain as a three-dimensional (3-D) reconstruction of brain energy use. Autoradiographs contain enormous amounts of potentially useful data, but conventional analyses, based on tedious manual methods, can sample and analyze only a small portion of this information. Computer 3-D reconstruction provides a mechanism for observing and analyzing all the data; therefore, a system of computer programs was developed for this purpose. The programs use digital imaging methods for image registration, superimpose whole brain data sets, and allow resampling of the 3-D data in arbitrary planes for pixel-by-pixel comparisons among multiple 3-D sets. These programs operate on the mathematical properties of the images alone, obviating the need for manual image alignment. Various statistical analyses can be applied to the data directly to study the patterns of metabolic changes in different experiments. The system is applied to data from experiments on the influence of injectable anesthetics on cerebral glucose metabolism.