Objective:To examine the spatial and temporal distribution characteristics of first-time callers with suicidal ideation and risk factors related to suicidal ideation in a psychological assistance hotline in Henan Province.Methods:The computerised counselling operating system of the Henan Provincial Psychological Assis-tance Hotline was used to extract data from 31 401 callers who called the hotline between January 2020 and October 2023.A circular distribution and kernel density analysis were employed to investigate the spatial and temporal distri-bution of first-time callers with suicidal ideation.Binary logistic regression analysis was employed to investigate the risk factors for suicidal ideation.Results:A total of 5 494 first-time callers were included in the study,of whom 1 697(30.9％)reported suicidal ideation in the previous two weeks.The temporal distribution of suicidal ideation calls indicated a peak between 12:36 and 01:08.The weekly distribution further revealed that the majority of calls occurred on Fridays.In terms of spatial distribution,the primary hotspots for callers with suicidal ideation were clus-tered around Zhengzhou and Xinxiang.Meanwhile,the secondary hotspots exhibited a dispersed distribution across multiple centers within the province.Logistic regression analysis revealed that being under 20 years old(OR=11.85),being unemployed(OR=1.78),having psychological issues(OR=5.03),experiencing family relation-ship problems(OR=3.67),and facing economic hardships(OR=7.08)were risk factors for suicidal ideation.Conclusion:The time distribution of calls from individuals with suicidal ideation to the psychological as-sistance hotline in Henan Province exhibits a centralized trend,while the spatial distribution of calls demonstrates an imbalance.When receiving initial calls from individuals with suicidal ideation,particular attention should be paid to those aged 20 years old or younger,those who are unemployed,and those experiencing psychiatric,psychological,familial,and economic difficulties.

Objective:To examine the spatial and temporal distribution characteristics of first-time callers with suicidal ideation and risk factors related to suicidal ideation in a psychological assistance hotline in Henan Province.Methods:The computerised counselling operating system of the Henan Provincial Psychological Assis-tance Hotline was used to extract data from 31 401 callers who called the hotline between January 2020 and October 2023.A circular distribution and kernel density analysis were employed to investigate the spatial and temporal distri-bution of first-time callers with suicidal ideation.Binary logistic regression analysis was employed to investigate the risk factors for suicidal ideation.Results:A total of 5 494 first-time callers were included in the study,of whom 1 697(30.9％)reported suicidal ideation in the previous two weeks.The temporal distribution of suicidal ideation calls indicated a peak between 12:36 and 01:08.The weekly distribution further revealed that the majority of calls occurred on Fridays.In terms of spatial distribution,the primary hotspots for callers with suicidal ideation were clus-tered around Zhengzhou and Xinxiang.Meanwhile,the secondary hotspots exhibited a dispersed distribution across multiple centers within the province.Logistic regression analysis revealed that being under 20 years old(OR=11.85),being unemployed(OR=1.78),having psychological issues(OR=5.03),experiencing family relation-ship problems(OR=3.67),and facing economic hardships(OR=7.08)were risk factors for suicidal ideation.Conclusion:The time distribution of calls from individuals with suicidal ideation to the psychological as-sistance hotline in Henan Province exhibits a centralized trend,while the spatial distribution of calls demonstrates an imbalance.When receiving initial calls from individuals with suicidal ideation,particular attention should be paid to those aged 20 years old or younger,those who are unemployed,and those experiencing psychiatric,psychological,familial,and economic difficulties.

BACKGROUND: Glaucoma is a kind of eye disease that can cause irreversible blindness which is characterized by visual field loss. Clinical research shows that the optic nerve head has changed before the visual field loss. The morphological changes of the optic nerve head have become the key to determine the early diagnosis of glaucoma and disease development. So it has important significance for us to study the morphological changes of the tissues of optic nerve head under the high intraocular pressure.
OBJECTIVE: To establish three-dimensional finite element model of optic nerve head which includes choroid, retina and lamina cribrosa, and analyze the thickness of the optic nerve head under the acute high intraocular pressure.
METHODS: (1) We chose healthy cats without refractive media and other eye diseases. The tomographic sequence images of the optic nerve head of a cat were obtained with the intraocular pressure of the normal value by using enhanced depth imaging spectral-domain optical coherence tomography. (2) The three-dimensional model of the retina, choroid and lamina cribrosa was obtained. Three-dimensional model of optic nerve head was established by assembling the model of the retina, the choroid and the lamina cribrosa. The thickness of the retina, choroid and lamina cribrosa was analyzed under different intraocular pressures by using the method of finite element analysis. (3) Animal model of acute ocular hypertension was established by methods of anterior chamber perfusion. The tomographic sequence images of the optic nerve head of a cat were obtained with different intraocular pressures by using enhanced depth imaging spectral-domain optical coherence tomography. Then, we measured the thickness changes of the choroid, retina and lamina cribrosa under different intraocular pressures, and compared with the results of finite element analysis.
RESULTS AND CONCLUSION: The thickness of the choroid, retina and lamina cribrosa trended to be thin, and the cup dish ratio of optic nerve head increased gradual y with the increased intraocular pressures. Regarding to the thickness changes of the choroid, retina and lamina cribrosa, the trend of experimental measurement results was consistent with finite element calculation results. Hence, it is feasible to analyze morphological changes of every fundus tissue under high intraocular pressure using the tomographic sequence images obtained by optical coherence tomography. We can predict the morphological changes of the optic nerve head tissue by finite element analysis, which has certain guiding significance in determining the progression of glaucoma.

BACKGROUND:The measure and prediction of the shape of optic nerve head are the key issues for early diagnosis and duration prediction of glaucoma. Therefore, it is significant to research the shape variation of optic nerve head under high intraocular pressure.
OBJECTIVE:To establish three-dimensional finite element model of optic nerve head and to analyze the deformation of optic nerve head and the change in retina thickness after acute high intraocular pressure.
METHODS:Animal model of acute ocular hypertension was established by methods of anterior chamber perfusion. The tomographic images of the optic nerve head of a cat were obtained at the normal intraocular pressure and 5 320 Pa, 7 980 Pa, 10 640 Pa, 13 300 Pa, 15 960 Pa intraocular pressures using optical coherence tomography. Then, we measured the variation of retinal thickness at typical location. Basing on the tomographic images of optic nerve head of a cat at normal intraocular pressure, we obtained three-dimensional structure of retina and choroid using software MIMICS. Then three-dimensional model of optic nerve head was established by assembling the retina and choroid. The deformation of optic nerve head and the change in retinal thickness under high intraocular pressure were observed using software ABAQUS. The effectiveness of the model was verified by the experimental result.
RESULTS AND CONCLUSION:With the increase of intraocular pressure, the retinal thickness is thinner, the optic nerve head depth, width and the ratio of the depth to width are gradual y increased. It suggests that the acute high intraocular pressure causes retinal thinning, optic nerve head widening and deepening. It is feasible to establish optic nerve head modeling in vivo by using optical coherence tomography, mechanical analysis can be applied to predict the shape variation of optic nerve head, which is significant to further deduce the pathological process of glaucoma.