RESUMEN
BACKGROUND:Previous brain studies have mostly focused on adults and fetuses,and the developmental characteristics of young children's brainstems have rarely been studied. OBJECTIVE:To observe the brainstem development characteristics of healthy young children and to explore the age-related differences and their correlation with sex. METHODS:From January 2019 to April 2022,a retrospective study of 3.0T MRI images of 174 children aged 2 to 6 years in the Affiliated Hospital of Inner Mongolia Medical University was conducted,and the median sagittal diameter,area and angle of the brainstem(including midbrain,pons and medulla oblongata)were measured. RESULTS AND CONCLUSION:There is an age-related increase in the anterior and posterior diameters of the midbrain,pons and medulla oblongata in the 2-5 years old group as well as in the longitudinal diameter and area of the midbrain,pons and medulla oblongata in the 2-6 years old group.Except for the longitudinal diameter of the medulla oblongata,all others show a positive correlation with age(r>0,P<0.05).In the 2-3 years old group and 4-5 years old group,the children are in the rapid growth and development stage,and these two age groups can be used as the key observation indicators for the development of young children.The anterior-posterior diameter,longitudinal diameter,area of the pons and total brainstem area are strongly correlated with age,which can be used as the key observation indicators for the brainstem development in young children.
RESUMEN
BACKGROUND: Radiation therapy is currently one of the main treatments for head and neck cancer. Radiation therapy can kill cancer cells, but it can also damage normal cells or tissues. OBJECTIVE: To summarize the research progress of the changed structure of radioactive salivary glands and repair in recent years. METHODS: PubMed database, Wanfang database and China Full-Text Journal Database were searched. The search terms were “salivary glands; radiation injury; histological change; cell therapy” in English and Chinese. The time range was from 1991 to 2020. By reading the title, abstract and full text, repetitive studies were excluded. Finally, 57 articles were summarized. RESULTS AND CONCLUSION: In the treatment of head and neck cancer patients, xerostomia caused by radioactive damage to salivary gland tissue is its typical chronic side effect. At present, it is believed that radiation will mainly affect the structure of salivary gland tissues and lead to the decline of its function, including changes in the structure of salivary glands and ducts, as well as changes in saliva secretion and excretion after blood vessel and nerve injury. However, the mechanism of radiation damage has not been pointed out. Studies have shown that stem cells derived from fat, bone marrow and human amniotic membrane epithelium can treat radiation-induced salivary gland damage, improve salivary secretion, and the transplanted cells can form secretory alveoli and duct structures in the body.