The prevalence of high myopia is increasing year by year and leads to a variety of ocular complications,of which pathological myopia has become a major cause of irreversible blindness worldwide.Patients with high myopia often suffer from reduced retinal perfusion and varying degrees of visual field defects.High myopia can cause irreversible damage to the fundus,leading to increased susceptibility to glaucoma and myopic maculopathy.Therefore,it is of great clinical sig-nificance to understand the characteristics of the fundus and complications of high myopia to slow the myopia progression and prevent complications.This article introduces the dangers of high myopia in details from the aspects of fundus perfu-sion,visual field defects and complications,aimed at guiding clinicians in early detection,diagnosis and intervention of high myopia and its complications to reduce the prevalence of high myopia and blindness and improve the vision and life quality of the general public.

Human challenge trial (HCT) is a test in which human volunteers are intentionally infected with pathogens in order to evaluate the efficacy of candidate preventive or therapeutic drugs. During the COVID-19 pandemic, the HCT of vaccines has aroused people's attention due to its significant advantages over clinical trial. This paper introduces the concept, development and application of HCT, the advantages and limitations of HCT for vaccine evaluation, and the consideration of future HCT of COVID-19 vaccine in China.

Corneal stroma is a significant part of the cornea and plays a significant role in the eye's refractive system. Although corneal transplantation is now the most effective treatment for corneal stromal disease, its advancement has been constrained by a shortage of donors, the need for prolonged immunosuppressive medicine to prevent rejection, and low graft survival rates. An alternate strategy is to use the corneal stroma's natural capacity for regeneration to create the ideal conditions for the collagenous extracellular matrix of the stroma to self-renew. However, it is challenging to replicate the intricate ultrastructure of the corneal stroma in vitro. Regenerative medicine has so been used to address these issues. These approaches refer to numerous disciplines, including stem cell-induced differentiation, tissue engineering and gene editing. This article provides potential directions for the future clinical applications of corneal stromal regeneration and repair while summarizing pertinent techniques, research progress, and issues.

Objective:To investigate the incidence and determinants of vaccine hesitancy towards national immunization program in China and understand the current status of parents' hesitancy to different vaccines used in national immunization program.Methods:A cross-sectional survey was conducted in Beijing, Sichuan and Gansu. The methods of proportional probability sampling and convenience sampling were used to select the eligible study subjects for questionnaire surveys.Results:A total of 3 592 parents were enrolled in the study, in whom 38.22% fully accepted all the vaccines, 59.35% agreed to let their children to receive all the vaccines but showed slight concern, and 2.42% had hesitancy to the vaccines. The vaccine with the most hesitancy was polio vaccine (0.89%), followed by diphtheria pertussis tetanus vaccine (0.70%) and hepatitis A vaccine (0.64%). The dominant reason for vaccine hesitancy was the risk-benefit perception of vaccination (31.03%), followed by the low awareness of the parents (21.84%) and the inconvenience caused by distance and time (21.84%).Conclusions:The incidence of vaccine hesitancy towards national immunization program was low in parents in China, but over 50% of the parents showed concern to the vaccines. It is essential to improve the service quality of national immunization program and strengthen the health education about the vaccination to reduce the incidence of vaccine hesitancy in parents.