COMPUTERIZED LOCALIZATION OF BRAIN STRUCTURES IN SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY USING A PROPORTIONAL ANATOMICAL STEREOTAXIC ATLAS

An accurate identification of cerebral structures is necessary to perf orm quantification of single photon emission computed tomography (SPEC T). We have developed an anatomical localization system that accounts for individual brain shapes and sizes by using the Talairach proportio nal grid system. The locations of the commissural lines, which define the stereotactic coordinate system, are calculated from the external l andmarks provided by the canthomeatal line. This is validated on MRI i mages. When applied to SPECT data, the use of a neuroanatomical atlas data along with the automaticity of the processing guarantees a high d egree of objectivity and inter-observer reproducibility.