Hippocampus is the most informative object of the brain for the purpose of detection of Alzheimer's disease signs. This paper presents the approach which was developed for detection of hippocampus and subsequent calculation of its parameters while analyzing the series of images obtained in a sagittal projection by means of a magnetic resonance tomography. This paper introduces the algorithms for detecting the keyframes in the entire series which contain the hippocampus and for identifying the hippocampus among other brain structures. The problems of measuring the volumatric parameters of the hippocampus and calculating its characteristics are considered. These characteristics serve as the basis for instrumental calculation of the signs which characterize the possible presence of Alzheimer's disease.