Benchmarking the CoW with the TopCoW Challenge: Topology-Aware Anatomical Segmentation of the Circle of Willis for CTA and MRA

The Circle of Willis (CoW) is an important network of arteries connecting major circulations of the brain. Its vascular architecture is believed to affect the risk, severity, and clinical outcome of serious neuro-vascular diseases. However, characterizing the highly variable CoW anatomy is still a manual and time-consuming expert task. The CoW is usually imaged by two angiographic imaging modalities, magnetic resonance angiography (MRA) and computed tomography angiography (CTA), but there exist limited public datasets with annotations on CoW anatomy, especially for CTA. Therefore we organized the TopCoW Challenge in 2023 with the release of an annotated CoW dataset. The TopCoW dataset was the first public dataset with voxel-level annotations for thirteen possible CoW vessel components, enabled by virtual-reality (VR) technology. It was also the first large dataset with paired MRA and CTA from the same patients. TopCoW challenge formalized the CoW characterization problem as a multiclass anatomical segmentation task with an emphasis on topological metrics. We invited submissions worldwide for the CoW segmentation task, which attracted over 140 registered participants from four continents. The top performing teams managed to segment many CoW components to Dice scores around 90%, but with lower scores for communicating arteries and rare variants. There were also topological mistakes for predictions with high Dice scores. Additional topological analysis revealed further areas for improvement in detecting certain CoW components and matching CoW variant topology accurately. TopCoW represented a first attempt at benchmarking the CoW anatomical segmentation task for MRA and CTA, both morphologically and topologically.

ENHANCING SPORTING PERFORMANCE IN FIGURE SKATERS AGED 7–8 YEARS BASED ON DEVELOPING COORDINATION ABILITIES AND OPTIMIZING PSYCHOPHYSIOLOGICAL INDICATORS

Aim. The aim of this article is to develop coordination abilities in figure skaters aged 7–8 years from the initial training group with the help of a special educational and training program. Materials and methods. The study was conducted on the premises of the Trud sports complex in Togliatti. Twenty figure skaters aged 7–8 years from the initial training group participated in the experiment. All participants were divided into 2 subgroups: the experimental group (EG) and the control group (CG), 10 girls each. The main difference between groups was the use of a special exercise program in the experimental group aimed at the development of coordination abilities in figure skaters. In the control group, classes were held according to the standard educational program. The diagnostic technique included the computer program “Researcher of temporal and spatial properties of a person version 2.1”. Results. The article provides an experimental justification for the use of a set of exercises of special physical training (SPT) for the development of coordination abilities in skaters 7–8 years old. It was shown that at the initial stage of the pedagogical experiment (PE), the psychophysiological and motor indicators in the experimental and control groups did not differ significantly. Having introduced a set of exercises in the experimental group, we received a significant improvement in the spatio-temporal indicators and motor coordination compared to the control group. Conclusion. Using a set of exercises for the development of coordination abilities in figure skaters allows improving the ability of young skaters to move on ice and developing the locomotor functions of young skaters with improved coordination abilities.