Structural MRI of the hippocampus: а review

Introduction: Generalization and systematization of anatomical ideas about the hippocampus is an urgent academic and practical task due to the increasing involvement of radiologists and topometrists in the diagnosis of psychoneurological diseases, the etiology of which is directly or indirectly related to deviations in the structure of the hippocampus.

Objective: To summarize the structural visualization of the hippocampi using high-field MRI data.

Materials and methods: The literature search was carried out in open information databases in Russian and English Medline, PubMed, Web of Science, RSCI, eLIBRARY using keywords and phrases: «anatomy of the hippocampus», «MRI of the hippocampus», «genetics of neurogenesis», «radiogenomics of the hippocampus».

Results: Based on literature data and our own experience in using MRI in diagnosing hippocampal pathology, the key features of normal MRI anatomy of the hippocampus are described. The review examines current data on the characteristics of the blood supply to the hippocampi.

Discussion: Magnetic resonance anatomy of the hippocampus demonstrates its complex structure, emphasizing how accurately the structural data obtained in this case are combined with sectional anatomy. The genetic determination of the hippocampus has a wide polymorphism, which is reflected in its morphological structure in humans. The normal magnetic resonance anatomy of the hippocampus has a range of asymptomatic variants of its development (inversion of the intraventricular portion, cysts, asymmetry). The blood supply to the hippocampus is carried out from the carotid and vertebrobasilar basins, which must be taken into account in the topographic localization of the ischemic infarction focus. Based on the presented material, it should be assumed that normal and pathological anatomy are closely related to epileptogenesis, being an important etiological link in the development of temporal lobe epilepsy.

Conclusion: Magnetic resonance anatomy of the hippocampus demonstrates its complex structure, emphasizing how accurately the obtained structural data are combined with sectional anatomy. The genetic determination of the hippocampus has a wide polymorphism, which is reflected in its morphological structure in humans. Embryonic development and neurogenesis of the hippocampus occurs between the 6th and 15th weeks of gestation. The normal magnetic resonance anatomy of the hippocampus has a range of asymptomatic variants of its development (inversion of the intraventricular portion, cysts, asymmetry). The blood supply to the hippocampus is carried out from the carotid and vertebrobasilar basins, which must be taken into account in the topographic localization of the ischemic infarction focus. Based on the presented material, it should be assumed that normal and pathological anatomy are closely related to epileptogenesis, being an important etiological link in the development of temporal lobe epilepsy.

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