Correlating MRI-based brain volumetry and cognitive assessment in people with Down syndrome.

INTRODUCTION: Down syndrome (DS) is the most common genetic cause of intellectual disability. Children and adults with DS show deficits in language performance and explicit memory. Here, we used magnetic resonance imaging (MRI) on children and adults with DS to characterize changes in the volume of specific brain structures involved in memory and language and their relationship to features of cognitive-behavioral phenotypes. METHODS: Thirteen children and adults with the DS phenotype and 12 age- and gender-matched healthy controls (age range 4-25) underwent an assessment by MRI and a psychological evaluation for language and cognitive abilities. RESULTS: The cognitive profile of people with DS showed deficits in different cognition and language domains correlating with reduced volumes of specific regional and subregional brain structures, confirming previous related studies. Interestingly, in our study, people with DS also showed more significant parahippocampal gyrus volumes, in agreement with the results found in earlier reports. CONCLUSIONS: The memory functions and language skills affected in studied individuals with DS correlate significantly with the reduced volume of specific brain regions, allowing us to understand DS's cognitive-behavioral phenotype. Our results provide an essential basis for early intervention and the design of rehabilitation management protocols.

Distinct neuroanatomical and neuropsychological features of Down syndrome compared to related neurodevelopmental disorders: a systematic review.

Objectives: We critically review research findings on the unique changes in brain structure and cognitive function characteristic of Down syndrome (DS) and summarize the similarities and differences with other neurodevelopmental disorders such as Williams syndrome, 22q11.2 deletion syndrome, and fragile X syndrome. Methods: We conducted a meta-analysis and systematic literature review of 84 studies identified by searching PubMed, Google Scholar, and Web of Science from 1977 to October 2022. This review focuses on the following issues: (1) specific neuroanatomic and histopathological features of DS as revealed by autopsy and modern neuroimaging modalities, (2) language and memory deficits in DS, (3) the relationships between these neuroanatomical and neuropsychological features, and (4) neuroanatomic and neuropsychological differences between DS and related neurodevelopmental syndromes. Results: Numerous post-mortem and morphometric neuroimaging investigations of individuals with DS have reported complex changes in regional brain volumes, most notably in the hippocampal formation, temporal lobe, frontal lobe, parietal lobe, and cerebellum. Moreover, neuropsychological assessments have revealed deficits in language development, emotional regulation, and memory that reflect these structural changes and are more severe than expected from general cognitive dysfunction. Individuals with DS also show relative preservation of multiple cognitive, linguistic, and social domains compared to normally developed controls and individuals with other neurodevelopmental disorders. However, all these neurodevelopment disorders exhibit substantial heterogeneity among individuals. Conclusion: People with Down syndrome demonstrate unique neurodevelopmental abnormalities but cannot be regarded as a homogenous group. A comprehensive evaluation of individual intellectual skills is essential for all individuals with neurodevelopment disorders to develop personalized care programs.

Psychosocial Risk Factors for Alzheimer's Disease in Patients with Down Syndrome and Their Association with Brain Changes: A Narrative Review.

Several recent epidemiological studies attempted to identify risk factors for Alzheimer's disease. Age, family history, genetic factors (APOE genotype, trisomy 21), physical activity, and a low level of schooling are significant risk factors. In this review, we summarize the known psychosocial risk factors for the development of Alzheimer's disease in patients with Down syndrome and their association with neuroanatomical changes in the brains of people with Down syndrome. We completed a comprehensive review of the literature on PubMed, Google Scholar, and Web of Science about psychosocial risk factors for Alzheimer's disease, for Alzheimer's disease in Down syndrome, and Alzheimer's disease in Down syndrome and their association with neuroanatomical changes in the brains of people with Down syndrome. Alzheimer's disease causes early pathological changes in individuals with Down syndrome, especially in the hippocampus and corpus callosum. People with Down syndrome living with dementia showed reduced volumes of brain areas affected by Alzheimer's disease as the hippocampus and corpus callosum in association with cognitive decline. These changes occur with increasing age, and the presence or absence of psychosocial risk factors impacts the degree of cognitive function. Correlating Alzheimer's disease biomarkers in Down syndrome and cognitive function scores while considering the effect of psychosocial risk factors helps us identify the mechanisms leading to Alzheimer's disease at an early age. Also, this approach enables us to create more sensitive and relevant clinical, memory, and reasoning assessments for people with Down syndrome.

3D surgical planning of pediatric tumors: a review.

BACKGROUND: 3D surgical planning for the treatment of tumors in pediatrics using different neuroimaging methods is witnessing an accelerating and dynamic development. Until now, there have been many reports on the use of 3D printing techniques in different aspects of medical practice. Pediatric tumors mainly in the abdomen are among the most medical specialties that benefit from using this technique. The purpose of the current study is to review published literature regarding 3D surgical planning and its applications in the treatment of pediatric tumors and present challenges facing these techniques. MATERIALS AND METHODS: A completed review of the available literature was performed, effect sizes from published studies were investigated, and results are presented concerning the use of 3D surgical planning in the management of pediatric tumors, most of which are abdominal. RESULTS: According to the reviewed literature, our study comes to the point that 3D printing is a valuable technique for planning surgery for pediatric tumors in heart, brain, abdomen and bone. MRI and CT are the most common used techniques for preparing 3D printing models, as indicated by the reviewed reports. The reported studies have indicated that 3D printing allows the understanding of the anatomy of complex tumor cases, the simulation using surgical instruments, and medical and family education. The materials, 3D printing techniques and costs to be used depend on the application. CONCLUSION: This technology can be applied in clinical practice with a wide spectrum, using various tools and a range of available 3D printing methods. Incorporating 3D printing into an effective application can be a gratifying process with the use of a multidisciplinary team and rapid advances, so more experience would be needed with this technique to show a clinical gain.