Developmental Changes in the Thickness of the Cortex and Its Layers in the Paramedian Lobule of the Cerebellum in Children

Objective. To study developmental changes in the thickness of the cortex and its layers in the paramedian lobule of the cerebellum in children. Materials and methods. Studies were performed using post mortem specimens (62 cerebella) from children aged from birth to 12 years who had died as a result of trauma without brain injury. Computerized morphometry was used to measure the thickness of the cortex and its molecular and granular layers on Nissl-stained frontal histological sections of the cortex taken bilaterally from the area of the paramedian (thin) lobule (HVIIB) at the vertex of the cerebellar folia. Quantitative data were analyzed year by year. Results. Increases in cortical thickness in the paramedian lobule of the cerebellum occurred in four stages: in the right hemisphere from birth to 1, 3, 5, and 9 years, and in the left hemisphere to 1, 5, 7, and 9 years. Left-sided asymmetry of cerebellar cortical thickness was noted in children aged one and two years, and of molecular layer thickness in three-year-old children. Right-sided asymmetry was characteristic of granular layer thickness in three-year-old children and of cortical thickness in six-year-old children. The group mean thickness of the cortex and its layers in the paramedian lobule of the cerebellum reached the adult level by age nine years. Conclusions. The thickness of the cerebellar cortex and its layers in lobule HVIIB increased heterochronously and heterodynamically in the right and left cerebellar hemispheres in children in the first year of life and in the periods of the early, fi rst, and second periods of childhood (1–3 years, 4–7 years, and 8–12 years, respectively). No decreases were seen in the thickness of the cortex and its layers in the paramedian lobule of the cerebellum in children from birth to age 12 years. © 2021, Springer Science+Business Media, LLC, part of Springer Nature.