During long-term on-orbit flight, astronauts are affected by many factors such as weightlessness and space radiation, and their vision is also affected.Reduced visual perception has been described among the complaints of astronauts on mission.Space-associated neuro-ocular syndrome (SANS) refers to ocular physiological, neurological, and neuroimaging findings observed in astronauts after prolonged spaceflight.NASA first described the clinical manifestations of the disease in 2011, including optic disc edema, eyeball flattening, choroidal folds, and far-sighted displacement.Although the exact pathogenesis of SANS is still under investigation, several hypotheses have been proposed to explain this neuro-ocular phenomenon.Based on previous studies, this review summarizes the current hypotheses on the pathogenesis and influencing factors of SANS, the methods used to study simulated weightlessness on the ground, and the corresponding prevention and intervention measures.This burgeoning field of research is helping to protect the eye safety of astronauts and realize the possibility of future space travel.

During long-term on-orbit flight, astronauts are affected by many factors such as weightlessness and space radiation, and their vision is also affected.Reduced visual perception has been described among the complaints of astronauts on mission.Space-associated neuro-ocular syndrome (SANS) refers to ocular physiological, neurological, and neuroimaging findings observed in astronauts after prolonged spaceflight.NASA first described the clinical manifestations of the disease in 2011, including optic disc edema, eyeball flattening, choroidal folds, and far-sighted displacement.Although the exact pathogenesis of SANS is still under investigation, several hypotheses have been proposed to explain this neuro-ocular phenomenon.Based on previous studies, this review summarizes the current hypotheses on the pathogenesis and influencing factors of SANS, the methods used to study simulated weightlessness on the ground, and the corresponding prevention and intervention measures.This burgeoning field of research is helping to protect the eye safety of astronauts and realize the possibility of future space travel.

AIM: To evaluate the diopter errors and safety of secondary intraocular lens(IOL)implantation in the ciliary sulcus using a modified incision procedure in children with bilateral aphakia.METHODS: The data of 12 children(24 eyes)with bilateral aphakia who had undergone secondary foldable IOL implantation in the ciliary sulcus using a modified incision procedure from 2020 to 2021 were retrospectively reviewed. Incision-related complications were analyzed intraoperatively and at 1 d and 1 mo postoperatively. Best-corrected visual acuity(BCVA), axial length(AL), white-to-white(WTW), and refractive outcomes in terms of preoperative reserved diopters(PRD)and actual equivalent spherical diopters(AESD). The patients were divided into two groups by age(≤7 and >7 a), AL(<23 and ≥23 mm)and WTW(≤11.5 and >11.5mm), and the diopter errors between their AESD and PRD predicted based on the measurement results were compared.RESULTS: The patients comprised 9(75%)boys and 3(25%)girls. Two(17%)patients had anterior subcapsular cataracts, 4(33%)had posterior polar cataracts, and 6(50%)had nuclear cataracts. The mean age at cataract extraction was 6.4±1.61(3.4-8.9)mo. The mean interval between cataract extraction and secondary IOL implantation was 6.8±1.82(4.4-11.5)a. The mean preoperative BCVA was 0.49±0.33(1.0-0.1)LogMAR. The mean postoperative BCVA was 0.38±0.32(1.0-0.0)LogMAR. The mean AL was 23.56±1.96(19.00-26.38)mm, and the mean WTW was 11.5±0.92(9.3-13.9)mm. The mean PRD was 1.57±0.60(0.73-2.77)D, the mean AESD was 0.57±0.55(-0.50 to 1.75)D, and the mean difference between the AESD and PRD was -0.99±0.52(-2.22 to 0.32)D. The differences in the AESD and PRD between the groups according to age, AL and WTW were not statistically significant(P=0.59, 0.56, and 0.53, respectively).CONCLUSION: IOL implantation in the ciliary sulcus after a modified incision is safe and feasible for children with aphakia. It is necessary to subtract approximately 1 D of IOL power from the formula-selected power when implanting an IOL in the ciliary sulcus. Age, AL, and WTW do not significantly affect the difference.

Objective:To compare the characteristics of gait disorders between patients with idiopathic normal pressure hydrocephalus(iNPH)and Parkinson's disease(PD)patients.Methods:General clinical data and gait assessment results of 16 iNPH patients, 20 PD patients, and 23 healthy adults seeking treatment at Tianjin Huanhu Hospital between January 2020 and December 2020 were retrospectively analyzed.Gait analysis was conducted using the Mobility Lab? system with APDM Opal sensors from the US.Results:The 16 patients in the iNPH group had a mean age of(68.81±8.73), the 20 patients in the PD group had a mean age of(65.05±10.15), and the 23 adults in the control group had a mean age of(59.96±6.20).There was no significant difference in age between the iNPH group and the PD group( P>0.05).However, the iNPH group was older than the healthy control group( t=3.71, P<0.05).The disease duration of the iNPH group was(22.94±23.19)months, which was shorter than(92.60±53.70)months in the PD group( t=5.23, P<0.05).The mini-mental state examination(MMSE)score(17.13±7.08)and the Montreal Cognitive Assessment(MoCA)score(11.75±5.43)of the iNPH group were significantly lower than those in the PD group[(24.17±4.73), t=3.45, P<0.05、(21.29±5.82), t=4.86, P<0.05]and the control group[(26.70±1.61), t=5.31, P<0.05、(22.78±3.30), t=7.89, P<0.05].Compared with the PD group, the iNPH group had a significantly lower foot clearance[right: (1.65±0.76)cm vs.(2.56±1.30)cm]and smaller bilateral toe-off angles[left: (20.59±6.11)° vs.(28.43±6.36)°; right: (20.78±6.88)° vs.(28.12±7.49)°, t=3.74、3.02, respectively, all P<0.05].There were statistically significant differences in all gait parameters in iNPH patients compared with the control group( P<0.05). Conclusions:iNPH patients exhibit clear gait disturbance, which is more prominent than in PD patients.The wearable gait analysis system can accurately assess gait disorders in iNPH patients, and can be applied to gait assessment and the development of rehabilitation plans.

Objective:To analyze the disease burden of Parkinson's disease (PD) in China from 1990 to 2021 and predict the disease burden of PD from 2022 to 2030.Methods:Based on the data of PD incidence in China from the Global Burden of Disease Study 2021 (GBD 2021), changes in PD disease burden from 1990 to 2021 were analyzed. Age-period-cohort model was used to analyze the independent influences of age, period and cohort in PD incidence (according to age group of 5 years, patients were divided into 15 groups: group of 20-24 years, group of 25-29 years..., and group of 90-94 years; according to a 5-year period, patients were divided into 6 groups: group of 1992-1996, group of 1997-2001..., and group of 2017-2021; because of birth cohort=period-age, patients were divided into 20 birth cohorts: birth cohort of 1897-1906, birth cohort of 1902-1911..., and birth cohort of 1992-2001). Nordpred model was used to predict the disease burden of PD from 2022 to 2030.Results:(1) From 1990 to 2021, number of PD patients, and PD incidence and standardized incidence in China showed upward trends. The standardized incidence increased by 89.68% for the total population, 89.71% for males, and 77.64% for females. (2) PD incidence was low in young subjects and increased obviously in subjects aged 60 years. PD incidence in subjects aged 20-24 years or 90-94 years was 0.07/100 000 and 643.31/100 000, respectively. Compared with female subjects, male subjects aged 60-94 years had higher PD incidence. (3) The onset relative risk increased from 0.71 (95% CI: 0.69-0.73) in group of 1992-1996 to 1.17 (95% CI: 1.16-1.19) in group of 2017-2021 in the total population, increased from 0.68 (95% CI: 0.66-0.70) to 1.18 (95% CI: 1.16-1.21) in males, and increased from 0.75 (95% CI: 0.73-0.77) to 1.14 (95% CI: 1.12-1.16) in females. (4) Onset relative risk was 0.40 (95% CI: 0.33-0.48) in the earliest birth cohort (1897-1906), which increased to 1.81 (95% CI: 0.95-3.43) in the latest birth cohort (1992-2001). (5) Number of PD patients in males, females and total population in China would increase to 455 010, 301 173 and 756 183, respectively, and the standardized incidence would increase to 56.45/100 000, 32.28/100 000 and 43.40/100 000, respectively, till 2030. Conclusion:PD disease burden in China from 1990 to 2021 is severe, particularly among males and the elderly; the disease burden is projected to continue rising up till 2030.

Objective:To analyze the disease burden of Parkinson's disease (PD) in China from 1990 to 2021 and predict the disease burden of PD from 2022 to 2030.Methods:Based on the data of PD incidence in China from the Global Burden of Disease Study 2021 (GBD 2021), changes in PD disease burden from 1990 to 2021 were analyzed. Age-period-cohort model was used to analyze the independent influences of age, period and cohort in PD incidence (according to age group of 5 years, patients were divided into 15 groups: group of 20-24 years, group of 25-29 years..., and group of 90-94 years; according to a 5-year period, patients were divided into 6 groups: group of 1992-1996, group of 1997-2001..., and group of 2017-2021; because of birth cohort=period-age, patients were divided into 20 birth cohorts: birth cohort of 1897-1906, birth cohort of 1902-1911..., and birth cohort of 1992-2001). Nordpred model was used to predict the disease burden of PD from 2022 to 2030.Results:(1) From 1990 to 2021, number of PD patients, and PD incidence and standardized incidence in China showed upward trends. The standardized incidence increased by 89.68% for the total population, 89.71% for males, and 77.64% for females. (2) PD incidence was low in young subjects and increased obviously in subjects aged 60 years. PD incidence in subjects aged 20-24 years or 90-94 years was 0.07/100 000 and 643.31/100 000, respectively. Compared with female subjects, male subjects aged 60-94 years had higher PD incidence. (3) The onset relative risk increased from 0.71 (95% CI: 0.69-0.73) in group of 1992-1996 to 1.17 (95% CI: 1.16-1.19) in group of 2017-2021 in the total population, increased from 0.68 (95% CI: 0.66-0.70) to 1.18 (95% CI: 1.16-1.21) in males, and increased from 0.75 (95% CI: 0.73-0.77) to 1.14 (95% CI: 1.12-1.16) in females. (4) Onset relative risk was 0.40 (95% CI: 0.33-0.48) in the earliest birth cohort (1897-1906), which increased to 1.81 (95% CI: 0.95-3.43) in the latest birth cohort (1992-2001). (5) Number of PD patients in males, females and total population in China would increase to 455 010, 301 173 and 756 183, respectively, and the standardized incidence would increase to 56.45/100 000, 32.28/100 000 and 43.40/100 000, respectively, till 2030. Conclusion:PD disease burden in China from 1990 to 2021 is severe, particularly among males and the elderly; the disease burden is projected to continue rising up till 2030.

Recurrent corneal erosion (RCE), a common disease caused by repeated episodes of corneal epithelial defects, is characterized by the sudden onset of eye pain, usually upon first awakening.Among many causes of the disease, trauma is the most common one, followed by epithelial basement membrane dystrophy.The disease can be diagnosed via the characteristic medical history, ocular symptoms and slit-lamp examination.Treatment of RCE includes both conservative management and surgical management.Conservative treatment is the first choice for the primary patients, including medication, bandage contact lens, application of serum drops, coverage of cryopreserved amniotic membrane, etc.The appropriate surgical procedures should be performed in patients when the conservative therapy failed.Surgical treatment mainly includes epithelial debridement, diamond burr polishing, anterior stromal puncture, alcohol delamination, phototherapeutic keratectomy, photorefractive keratectomy, femtosecond laser-assisted lamellar keratectomy, etc.RCE treatment progress was comprehensively reviewed in this article to provide references for clinical therapy.

Objective:To investigate the effect and mechanism of bone marrow mesenchymal stem cell (BMSC)-derived exosomal microRNA-1297 (miR-1297) on hippocampal neuron damage in depressed rats.Methods:BMSCs and BMSCs-derived exosomes were prepared and identified. Rats were first injected with corticosterone to establish the model of depression, and then injected with BMSCs-derived exosomes. Superoxide dismutase (SOD), malondialdehyde (MDA), lactate dehydrogenase (LDH), TNF-α and IL-1β in rat serum samples, hippocampal tissues and neurons were detected. Expression of miR-1297 in hippocampal tissues and neurons was detected by RT-qPCR. A rat hippocampal neuron injury model was established to investigate the role of BMSC-derived exosomes and miR-1297 in neuronal apoptosis and proliferation. The targeting relationship between miR-1297 and connective tissue growth factor (CTGF) was analyzed using dual luciferase reporter genes.Results:In the hippocampus of depressed rats, the expression of miR-1297 was low, while the expression of CTGF was elevated. Exosomes derived from BMSCs can inhibit the expression of CTGF by up-regulating the level of miR-1297, thereby inhibiting neuronal cell apoptosis in the hippocampus of depressed rats, while increasing the level of SOD, and reducing inflammatory damage, and ultimately improving the behavioral function of depressed rats.Conclusions:Depressed rats showed decreased expression of miR-1297 and increased expression of CTGF. BMSC-derived exosomes inhibited CTGF expression through up-regulating miR-1297, thereby improving hippocampal neuron damage in rats with depression.

The optic nerve is the only pathway that transduct visual signals into visual centers, and is consisted of retinal ganglion cells and glial cells. Astrocytes, the most abundant neuroglia in center nerve system (CNS), are considered as structural supporter and carrier of metabolic components of neurons. In recent years, astrocytes have become treasure of neurological study due to their dual effects after nerve injury. The neurotoxic reactive astrocytes are termed as A1-type, and the neuroprotective ones are termed as A2-type. For the purpose of reducing neuron loss after optic nerve injury, it is critical to find out proper management methods of astrocyte reactivity. In this paper, we will concentrate on the inducers, mechanisms and influences of astrocyte reactivity in optic nerve and CNS, and then, summarize present possible interference ways to a neuroprotective outcome.

Background The innovation of pre-chop technique lies in shortening surgery duration,reducing ultrasound power,and deseasing the loss of corneal endothelial cells (CECs).Objective This study was to compare the efficacy and safety of pre-chop technique using a reverse-chopper and phaco-and-chop phaco technique to super high myopia associated with hard nucleus cataract.Methods A prospective randomized-controlled-clinical interventional study was performed.Fourty eyes of 40 high myopia associated with cataract patients with Ⅲ-ⅣV degree of nucleus were enrolled in Beijing Tongren Hospital from March to September 2016.The patients were randomized into the pre-chop group and matched phaco-and-chop group according to random number table,and the self-made reverse chopper-assisted pre-chop phacoemulsification (phaco) surgery and phaco-and-chop phaco surgery were performed on the eyes of different groups,respectively.The phaco power,effective phaco duration and best corrected visual acuity (BCVA) were recorded and compared between the two groups to evaluate the efficacy,and the loss rate of corneal endothelial cells and eyes in different grades of cornea edema after operation were compared between the two groups to assess the safety of surgery procedure.Written informed consent from each patient was obtained prior to relevant examination and surgery.Results The surgery was finished smoothly in the eyes.The mean effective phaco duration was (47.30±11.29) seconds and (57.70± 14.51) seconds in the pre-chop group and phaco-andchop group,respectively,with a significant difference between them (t =-2.530,P =0.016).The BCVA was better at the seventh day after surgery in the pre-ehop group than that in the phaco-and-chop group (4.75t0.11 vs.4.67± 0.14),showing a significant difference between the two groups (t=2.147,P=0.038).In 1 month after surgery,the CECs loss rate was (10.82±3.77)％ in the pre-chop group,which was lower than (16.11±6.47)％ in the phacoand-chop group (t=-3.758,P=0.001).The number of the eyes with grade 2-3 of corneal edema in the pre-chop group was significantly decreased in comparison with the phaco-and-chop group 7 days after surgery (Z =11.822,P=0.008).Conclusions Compared with the conventional phaco-and-chop technique,reverse-chopper prechop technique appears to have a better efficacy and safety in phaco surgery for high-myopia associated with hard nuclear cataractous eyes.