Search

To characterize the findings of eyes with choroidal vascular hyperpermeability (CVH), a hallmark of central serous chorioretinopathy, using multimodal imaging and investigate the locational agreement between these findings and CVH.Among patients with central serous chorioretinopathy in either eye, eyes with CVH identified using indocyanine green angiography without exudative changes were included. All eyes were examined using funduscopy, fluorescein angiography, spectral-domain optical coherence tomography, and short-wavelength or near-infrared autofluorescence (SWAF or NIRAF). The locational agreement between CVH and imaging findings was evaluated for each modality. The relative index on how they overlapped was calculated as the overlapping index. Binarized images, particularly for NIRAF, were also evaluated.This study included 69 CVH sites in 33 eyes of 28 patients. Pachydrusen was detected in 36% of CVH sites. Fluorescein angiography revealed hyperfluorescent areas in 39% of CVH sites. Optical coherence tomography findings identified 65% of CVH sites, but the overlapping index was 5%. Short-wavelength or near-infrared autofluorescence imaging identified 89% of CVH sites, but they exhibited variable autofluorescence. NIRAF imaging revealed hypoautofluorescence findings in all CVH sites. When binarized, near-infrared autofluorescent dark dots were observed in all CVH sites. Overlapping indices before and after binarization were 78% and 98%, respectively. The near-infrared autofluorescent dark dots area corresponded well with that of CVH (intraclass correlation coefficient, 0.987 [95% confidence interval, 0.952-0.995]).Hypoautofluorescent findings revealed on NIRAF imaging, especially after binarization processing, corresponded well with CVH sites. These multimodal imaging results may help investigate the anatomical or locational characteristics of CVH in patients with central serous chorioretinopathy.

Despite the increasing popularity of autologous breast reconstruction, limited evidence is available. The aim of the present study was to compare the short-term outcomes of pedicled- and free-flap breast reconstructions.Using a nationwide Japanese inpatient database, we identified 13,838 patients who underwent breast reconstruction for breast cancer (July 2010-March 2020) using a pedicled or free-flap (pedicled- and free-flap groups, n = 8279 and 5559, respectively). One-to-one propensity score matching was performed to compare the occurrence of postoperative complications, duration of anesthesia, length of stay, and total costs between the two groups. We also performed subgroup analyses stratified by hospital volume.The propensity score-matched analysis involving 3524 pairs showed that the pedicled-flap group had significantly lower proportions of takeback (2.1% vs. 3.2%, p 0.001), thrombosis (0.6% vs. 1.7%, p 0.001), and postoperative bleeding (2.1% vs. 5.7%, p 0.001) than the free-flap group. No significant differences were found in wound dehiscence or tissue necrosis. Compared to the free-flap group, the pedicled-flap group had a short duration of anesthesia (412 vs. 647 min, p 0.001) and low total hospitalization costs (12 662 vs. 17 247 US dollars, p 0.001) but a prolonged postoperative length of stay (13 vs. 12 days, p 0.001). The subgroup analyses showed results compatible with those of the main analysis.In this large nationwide cohort of patients who underwent breast reconstruction, pedicled-flap reconstruction was associated with fewer postoperative complications (excluding necrosis and wound dehiscence) and lower hospitalization costs but a longer postoperative length of stay than free-flap reconstruction.

We compared the predictive performance of gradient-boosted decision tree (GBDT), random forest (RF), deep neural network (DNN), and logistic regression (LR) with the least absolute shrinkage and selection operator (LASSO) for 30-day unplanned readmission, according to the number of predictor variables and presence/absence of blood-test results. We used electronic health records of patients discharged alive from 38 hospitals in 2015–2017 for derivation (n=339,513) and in 2018 for validation (n=118,074), including basic characteristics (age, sex, admission diagnosis category, number of hospitalizations in the past year, discharge location), diagnosis, surgery, procedure, and drug codes, and blood-test results. We created six patterns of datasets having different numbers of binary variables (that ≥5% or ≥1% of patients or ≥10 patients had) with and without blood-test results. For the dataset with the smallest number of variables (102), the c-statistic was highest for GBDT (0.740), followed by RF (0.734), LR-LASSO (0.720), and DNN (0.664). For the dataset with the largest number of variables (1543), the c-statistic was highest for GBDT (0.764), followed by LR-LASSO (0.755), RF (0.751), and DNN (0.720). We found that GBDT generally outperformed LR-LASSO, but the difference became smaller when the number of variables was increased and blood-test results were used.

Background/Objectives Although lifestyle habits may represent modifiable risk factors of glaucoma, the association between lifestyle factors and glaucoma is not well understood. The aim of this study was to investigate the association between lifestyle habits and the development of glaucoma. Subjects/Methods Participants who underwent health check-ups from 2005 to 2020 using a large-scale administrative claims database in Japan were included in the study. Cox regression analyses were performed where glaucoma development was regressed on the lifestyle (body mass index, current smoking, frequency and amount of alcohol consumption, eating habits, exercise habits and quality of sleep), age, sex, hypertension, diabetes mellitus and dyslipidaemia. Results Among the 3,110,743 eligible individuals, 39,975 developed glaucoma during the mean follow-up of 2058 days. Factors associated with increased risk of glaucoma were overweight/obese (vs. moderate weight: hazard ratio, 1.04 [95% confidence interval, 1.02–1.07]), alcohol consumption of 2.5–4.9 units/day, 5–7.4 units/day, and ≥7.5 units/day (vs. Conclusions Moderate body mass index, having breakfast, avoiding late dinner, limiting alcohol intake to

Background/Objectives: This study aimed to compare the cost-effectiveness of prophylactic laser peripheral iridotomy (LPI) with that of observation for primary angle-closure suspect (PACS) in Japan. Subjects/Methods: A Markov model was developed to compare the costs and utilities of prophylactic LPI with those of observation of 40-year-old patients with PACS. In the model with a yearly cycle over a 20-year time horizon, the disease was postulated to irreversibly progress from PACS to primary angle closure, followed by primary angle-closure glaucoma, unilateral blindness, and bilateral blindness. The parameters were estimated based on a recent randomised controlled trial and analyses of Japanese claims data. The incremental cost-effectiveness ratio was estimated from the healthcare payer’s perspective and evaluated as the willingness-to-pay 5 million Japanese Yen per quality-adjusted life-year. The observation period was shortened, and the age at entry into the cohort was changed to 50 years in the sensitivity analyses. We conducted one-way deterministic sensitivity analysis and probabilistic sensitivity analysis with Monte Carlo simulations with 10 000 iterations. Results The incremental cost-effectiveness ratio of LPI was 2 270 224 Japanese Yen (14 189 pounds sterling) per quality-adjusted life-year, which was below the willingness-to-pay threshold. The ratios were approximately 4 and 8 million in the 15-year and 10-year time horizons, respectively. Increasing the age at entry had little influence on the incremental cost-effectiveness ratio. The deterministic and probabilistic sensitivity analyses indicated that the results were robust. Conclusions Our results indicate that prophylactic LPI for middle-aged patients with PACS is cost-effective in Japan.

Background Intravenous immunoglobulin (IVIg) has been reported to be an effective treatment for bullous pemphigoid. However, the impact of IVIg approval on real-world outcomes remains unclear. Objectives To investigate the effect of IVIg approval on patients with bullous pemphigoid using a national inpatient database. Methods Using the Japanese Diagnosis Procedure Combination database, we identified 14 229 patients admitted to hospital for bullous pemphigoid and treated with systemic corticosteroids between July 2010 and March 2020. We conducted an interrupted time-series analysis to compare in-hospital mortality and morbidity between the patients admitted before and after the approval of reimbursement of IVIg for bullous pemphigoid in the Japanese universal health insurance system in November 2015. Results In-hospital mortality was 5.5% before and 4.5% after the approval of IVIg reimbursement. After the IVIg approval, 18% of the patients were treated with IVIg. Based on the interrupted time-series analysis, in-hospital mortality significantly decreased at the time of approval [–1.2%, 95% confidence interval (CI) –2.0 to –0.3, P = 0.009] and a downward trend was observed after the approval (–0.4% annual rate, 95% CI –0.7 to –0.1, P = 0.005). In-hospital morbidity also demonstrated a downward trend after the approval. Conclusions IVIg approval is associated with lower in-hospital mortality and morbidity in inpatients with bullous pemphigoid.

Purpose To analyze the incidence of sympathetic ophthalmia (SO) after inciting events (eye trauma or intraocular surgery). Design Retrospective cohort study. Participants Patients experiencing inciting events between 2012 and 2019. Onset of SO was defined as the first date of SO diagnosis. Methods Using a nationwide administrative claims database in Japan, we calculated the cumulative incidence of SO after inciting events stratified by sex, 10-year age groups, and a categorical variable of primary or repeated, reflecting the history of inciting events in the past year (no inciting events, inciting events without trauma, or inciting events with trauma) using the Kaplan-Meier approach. We also estimated the adjusted hazard ratio (aHR) by Cox regression. We then restricted the population to those with only 1 inciting event during the observation period to investigate the pure effect of each inciting event. Main Outcome Measures Cumulative incidence of SO over 60 months. Results A total of 888 041 inciting events (704 717 patients) were eligible. The total number of SO cases was 263, and the cumulative incidence of SO was 0.044% over 60 months. Female sex was not associated with onset of SO (aHR, 1.01; 95% confidence interval [CI], 0.79–1.29; P = 0.95). The group 40 to 49 years of age showed the highest incidence of 0.104% among the age groups (aHR vs. ≥80 years of age group [0.041%], 2.44 [95% CI, 1.56–3.80]; P Conclusions The cumulative incidence of SO over 60 months was estimated to be 0.044% at minimum. Repeated inciting events, especially those with trauma, increased the risk of SO developing. Trauma was 4 to 5 times as likely to induce SO than vitrectomy. The present findings will be valuable for counseling patients about the risks of SO after trauma and before performing intraocular surgeries.

Gyro finishing —a type of mass finishing—is one of the potential processes for finishing complicated shapes. This study proposes a cover plate located above a workpiece to improve finishing efficiency in gyro finishing. First, the effect of the cover plate on the force acting on the workpiece, which is related to the finishing efficiency, was investigated, and we confirmed that the force increased by using the cover plate. This was considered to be caused by the restriction of upward motion of the abrasive media. Subsequently, the effect of the cover plate on the finishing efficiency was evaluated by comparing the surface roughness variation with and without the cover plate. The finishing efficiency of the workpiece surface increased by approximately a factor of 2.0 with the cover plate due to the large force acting on the workpiece. Additionally, the bad effect caused by using the cover plate via larger force acting on the workpiece―worsening of the surface roughness―was not revealed. Therefore, the cover plate was confirmed a highly effective method to improve its performance. Furthermore, the effect of the cover plate was investigated under the workpiece-stopped condition for an improved understanding. We confirmed that the surface roughness obtained using the cover plate improved over the entire front surface of the workpiece due to the increase of the contact pressure.

To clarify recent trends in glaucoma surgery in Japan, including minimally invasive glaucoma surgery.Retrospective cohort study.We used the Diagnostic Procedure Combination database, a nationwide administrative database in Japan. Patients who underwent glaucoma-related procedures were included. We calculated the number of surgeries stratified by procedures and age categories. We also investigated the number of glaucoma-related procedures in combination with cataract surgery.From fiscal years 2011 to 2019, we identified 134,331 glaucoma-related procedures at 720 hospitals. The total number of glaucoma-related procedures increased by 215% from 6516 in 2011 to 20,569 in 2019. The numbers of filtering surgeries, trabeculotomies, and glaucoma drainage devices with plates [GDD(p +)] procedures significantly increased (P = 0.002, 0.002, and 0.006, respectively), whereas the number of cyclocryotherapy procedures significantly decreased (P = 0.002). The number of iStent procedures increased by 49% from 371 in 2018 to 551 in 2019. The ≥ 65 year age group accounted for 80% of the iStent procedures. In the 0 to 14 year age group, trabeculotomy accounted for about 70% of the procedures, and the GDD(p +) procedure became the second most common procedure after trabeculotomy because of the decrease in filtering surgeries. Among combination surgeries, trabeculotomy was most frequently performed. The proportion of combination surgery increased, especially in trabeculotomy.The total number of glaucoma-related procedures increased throughout the observation period. Before 2017 filtering surgery was the most common procedure, whereas trabeculotomy was most common after 2018. The proportion of trabeculotomies performed in combination with cataract surgery continuously increased.

A calculation method for workpiece profile variation during double-sided lapping was developed in this study. In this method, shell element in FEM deformation was used to formulate elastic deformation of workpiece, and spring element was used to formulate the contact between workpiece and platens to calculate distribution of their contact pressure considering workpiece elastic deformation. First, the developed method of the contact pressure distribution was evaluated by comparing with a method using a FEM software and the existing methods, and was confirmed to be quite valuable in terms of applicable process and calculation time. Subsequently, the workpiece profile variation was calculated using the developed method for several workpiece conditions, and it was clarified that the uneven workpiece thickness can be modified by the process, but it is difficult to modify the bow shape when the workpiece is not small. Furthermore, the decrease of the load applied to the workpiece was suggested to modify the bow shape of the workpiece.

BackgroundThe most effective dosage of aspirin to prevent coronary artery abnormalities in patients with acute Kawasaki disease remains unknown. Using a Japanese national inpatient database, this study aimed to identify the appropriate dose of aspirin to be prescribed to patients with acute Kawasaki disease.MethodWe used the Diagnostic Procedure Combination database to identify patients with Kawasaki disease treated with intravenous immunoglobulin between 2010 and 2021.The outcomes included the occurrence of coronary artery abnormalities and intravenous immunoglobulin resistance, length of stay, and medical costs. Restricted cubic spline functions were performed to examine the association between aspirin dose and the outcomes.ResultsData of 82109 patients were extracted from the database. Non-linear associations were observed between aspirin dose and the outcomes. In comparison with an aspirin dose of 30 mg/kg/day, the odds ratio (95% confidence interval) for coronary artery abnormalities was 1.40 (1.13–1.75) at 5 mg/kg/day. An aspirin dose of ≥30 mg/kg/day did not significantly change the odds ratio for coronary artery abnormalities. Compared with a dose of 30 mg/kg/day, the odds ratio (95% confidence interval) for intravenous immunoglobulin resistance was 0.87 (0.76–1.00) at 5 mg/kg/day and 0.59 (0.36–0.98) at 80 mg/kg/day. An increase in aspirin dose was associated with a shorter length of stay and lower medical costs.ConclusionsLow-dose aspirin may increase the risk of coronary artery abnormalities in patients with acute Kawasaki disease; however, increasing aspirin doses beyond the standard doses may not be associated with a reduction in coronary artery abnormalities. High-dose aspirin showed the potential to reduce hospital stay and medical costs without increasing complications.Article SummaryThe study showed by restricted cubic spline that the dose of aspirin was no significant association between aspirin escalation and CAAs in patients with acute KD.What’s Known on This SubjectAspirin is standard treatments used with IVIG of acute Kawasaki Disease (KD), Few studies have shown the most effective dosage of aspirin to to prevent CAAs.What This Study AddsThe dose of aspirin was no significant association between aspirin escalation and CAAs in patients with acute KD.

In double-sided lapping and polishing processes, the friction coefficients between the workpiece and platens or pads are important parameters for understanding or improving the lapping and polishing processes. However, the friction coefficients have not been investigated in detail owing to insufficient measurement methods for the torques acting on the upper and lower platens, which are necessary to evaluate the friction coefficients. Thus, a novel measurement method for the torque acting on the upper platen in a three-way double-sided machine was proposed in this study. In the method, the torque is measured based on the forces acting on the holders supporting the upper platen rotation. The torques were measured with the method in double-sided lapping experiments, and they were confirmed to agree with the theoretical torque variation. Furthermore, the friction coefficient between the workpiece and upper pad identified with the proposed method was also verified by comparing with the friction coefficient measured in the single-sided lapping experiment. In addition, the estimation method of the lower platen torque based on the motor torque was investigated by utilizing the proposed method, and we found the lower platen torque was estimated accurately by taking a sufficient warm-up time or by modeling the torque loss in transmission path. Therefore, accurate measurement of the torques acting on the upper and lower platens, which is an effective tool for understanding or improving the process, was realized.

To analyze the vessel density around the optic nerve head (ONH) by optical coherence tomography angiography (OCTA) in patients with retinitis pigmentosa (RP), and to evaluate its correlation with visual functions. Thirty-eight eyes with RP with visual field constriction within the central 10° were enrolled. The mean (± SD) age of the patients was 43.7 ± 15.1 years. In addition to visual acuity (VA) measurements and visual field tests (Humphrey Field Analyzer 10–2 test), we also measured the vessel density at the macula by OCTA (superficial and deep vessel density: sVD(m) and dVD(m)) and in multiple layers around the ONH (vessel density in the radial peripapillary capillary [RPC] layer and in the nerve head [NH] layer: VDrpc and VDnh). The vessel density was calculated by binarizing the OCTA images. The associations between the logMAR VA and mean deviation (MD) values and the variables of central retinal thickness (CRT), sVD(m), dVD(m), VDrpc, VDnh, and also the size of the foveal avascular zone were investigated. The mean logMAR VA was 0.16 ± 0.34 and the MD value was − 17.2 ± 10.3 dB; the MD value was significantly related to the logMAR VA (p = 0.0028). Multivariate analysis with AICc model selection suggested only dVD(m) was associated with logMAR VA. On the other hand, the optimal model for the MD value included the CRT, dVD(m), and VDnh. The vessel density in the deep layer around the ONH was significantly associated with the visual field deterioration in patients with RP.

Pemphigus is a life-threatening autoimmune blistering disease. Patient characteristics, treatment courses, and outcomes remain unclear owing to its rarity. To describe the background, treatment, and outcomes of pemphigus, we identified 2598 patients with pemphigus vulgaris and 1186 patients with pemphigus foliaceus from a nationwide inpatient database in Japan. Patients with pemphigus vulgaris were younger (62 vs 72 years, P 0.001), had fewer comorbidities, and were more likely to be admitted to high-volume hospitals (38% vs 30%, P 0.001) than those with pemphigus foliaceus. Patients with pemphigus vulgaris had undergone more aggressive treatment, including steroid pulse therapy, intravenous immunoglobulin, or plasmapheresis, compared with those with pemphigus foliaceus (48% vs 42%, P = 0.001); specifically, in patients aged70 years, the pemphigus vulgaris group was more likely to undergo aggressive treatment than the pemphigus foliaceus group (52% vs 45%), whereas there was no significant difference in patients aged ≥70 years (40% vs 40%). Immunosuppressive agents (30% vs 26%, P = 0.015) and analgesics, including opioids (45% vs 36%, P 0.001), were used more frequently, whereas topical corticosteroids were used less frequently (32% vs 48%, P 0.001) in patients with pemphigus vulgaris compared with those with pemphigus foliaceus. In-hospital mortality was lower in patients with pemphigus vulgaris than in those with pemphigus foliaceus (2.2% vs 4.0%, P = 0.002); in the comparison stratified by age, the mortality was equivalent among the two groups (0.6% in patients aged70 years and 6.1% in those aged ≥70 years). Overall, patients with pemphigus vulgaris had a 10-day longer hospitalization period and higher hospitalization costs than those with pemphigus foliaceus. Our findings provide useful information for understanding the current trends in the management of pemphigus in Japan.

To investigate retinal thickness parameters in the elderly with prediabetes mellitus (preDM) and type 2 DM without retinopathy (non-diabetic retinopathy [NDR]).This cross-sectional study included a total of 1273 eyes without retinal pathologies of 699 volunteers aged ≥ 65 years were included. The eyes were categorized into non-DM (606 eyes), preDM (480 eyes), and NDR (187 eyes) groups according to their HbA1c levels. Fundus photography, swept-source optical coherence tomography, and comprehensive systemic examination were conducted. The thicknesses of the retinal nerve fiber layer in the macula (mRNFL) and peripapillary (pRNFL), ganglion cell complex (GCC), and ganglion cell inner plexiform layer (GCIPL), as well as central subfield thickness (CST) and central foveal thickness (CFT) were investigated for their association with DM stage using linear mixed model.A statistically significant thinning of mRNFL was observed in preDM vs. non-DM and in NDR vs. preDM in 3/6 sectors. A significant thinning of pRNFL was observed in preDM vs. non-DM and in NDR vs. preDM in 2/12 sectors. Such DM stage-dependent thinning of RNFL was observed mainly in the temporal and superior sectors. GCIPL and GCC were less sensitive to reflect DM-dependent inner retinal thinning. CST and CFT were not significantly associated with different DM stages.The thinning of mRNFL in the temporal and superior sectors might be a sensitive parameter associated with early neurodegeneration in preDM and NDR.

We investigated the association between exposure to eye drops prescribed for dry eye disease (DED) during pregnancy and adverse neonatal outcomes. Pregnant women with DED in the JMDC Claims Database (JMDC Inc., Tokyo, Japan) between 2005 and 2020 were included. According to their prescriptions during the first trimester, the women were classified into three exposed groups (hyaluronate 0.1% alone, hyaluronate 0.3% alone, and diquafosol alone) and an unexposed group (no eye drops for DED). We compared adverse neonatal outcomes (congenital anomalies, preterm birth, low birthweight, and composite outcome of these three) between the exposed and unexposed groups. We conducted a high-dimensional propensity score analysis using many variables in the database together with known potential confounders such as chronic comorbidities. We identified 4,808 eligible women, of whom 936 (19.5%) received eye drops for DED. Congenital anomalies occurred in 7.2% and 6.0%, preterm birth in 3.1% and 4.0%, low birthweight in 7.9% and 6.0%, and composite outcome in 14.9% and 12.3% of women in the hyaluronate 0.1% alone and unexposed groups, respectively. The high-dimensional propensity score analysis showed that hyaluronate 0.1% alone was not significantly associated with increases in congenital anomalies (risk difference, 0.4% [95% confidence interval, -1.9% to 2.7%]), preterm birth (-0.6% [-2.2% to 0.9%]), low birthweight (1.8% [-0.6% to 4.1%]), or composite outcome (1.9% [-1.3% to 5.1%]). Similar results were obtained in the hyaluronate 0.3% alone and diquafosol alone groups. Use of eye drops for DED in pregnant women was not associated with adverse neonatal outcomes.

It is unknown whether depression and anxiety-related conditions associate with poor perinatal outcomes, especially live birth rates, among women diagnosed with recurrent pregnancy loss. We performed a retrospective cohort study using the Japanese Medical Data Centre Claims Database and identified women diagnosed with recurrent pregnancy loss. Live birth rates were compared as the primary outcome between patients with and without depression and/or anxiety-related disorders. A stabilised inverse probability of treatment weight analysis using propensity scores was also performed to assess the association. Among 5,517 eligible patients, there were 804 (14.6%) women who had depression and/or anxiety-related disorders during treatment for recurrent pregnancy loss during pregnancy. The overall live birth rates differed significantly between the groups according to the Kaplan–Meier method and log-rank test (p = 0.011). However, Cox proportional-hazards regression model and stabilised inverse probability of treatment weight analysis showed no statistically significant association between depressive disorders and live birth rates. The current study showed that approximately 15% of patients diagnosed with recurrent pregnancy loss develop depressive disorders. After accounting for variables, we found no independent association between depressive disorders after recurrent pregnancy losses and low live birth rates.

The optimal value of body mass index (BMI) for the development of hypertension and the influence of BMI on the development of stage 1 or stage 2 hypertension remain unclear.We sought to identify the BMI threshold for the prevention of hypertension and how changes in BMI would influence the risk of developing hypertension.We analyzed 1,262,356 participants (median age;43 years;50.9% men) with normal blood pressure (BP) (systolic BP [SBP]120 mmHg and diastolic BP [DBP]80 mmHg) or elevated BP (SBP 120-129 mmHg and DBP 80 mmHg). The primary outcome was stage 1 (SBP 130-139 mmHg or DBP 80-89 mmHg) or stage 2 hypertension (SBP ≥ 140 mmHg or DBP ≥ 90 mmHg). We analyzed the relationship between baseline BMI, change in BMI, and the risk of developing hypertension using generalized additive models with a smoothing spline.During the median follow-up of 851 days, 341,212 cases of stage 1 hypertension and 70,968 cases of stage 2 hypertension were detected. The risk of developing stage 1 or stage 2 hypertension increased steeply after BMI exceeded 20 kg/m2. The annual change in BMI was positively correlated with the risk of developing stage 1 or 2 hypertension. Contour mapping using generalized additive models demonstrated an additive increase in the risk of developing hypertension with higher baseline BMI and increases in BMI over one year. Body weight gain increases the risk of developing hypertension even in underweight or normal-weight individuals based on the World Health Organization classification.In Japanese adults with normal or elevated BP, risk of developing hypertension increased with BMI when baseline BMI was greater than 20 kg/m². Body weight gain additively interacted with baseline BMI during hypertension development. Our results underscore the importance of maintaining body weight in preventing the development of hypertension.

To investigate the risk of ocular adverse events after Coronavirus Disease 2019 (COVID-19) mRNA vaccination.Matched cohort and self-controlled case series (SCCS) studies.We used a population-based database of medical claims and vaccination records in a large Japanese city. In the matched cohort study, we identified individuals who received COVID-19 vaccination (BNT162b2) from February 2021 to September 2021. One control was selected from nonvaccinated individuals by matching time, date of birth, sex, Charlson comorbidity index, and the enrollment period for health insurance. In the SCCS study, we analyzed individuals who developed ocular adverse events.In the matched cohort study, we applied the Kaplan-Meier estimator to estimate the cumulative incidence of ocular adverse events over 21 days after the first dose and 84 days after the second dose. In the SCCS method, we used conditional Poisson regression to estimate the incidence rate ratio (IRR) of ocular adverse events during the risk periods (0-21 days after the first dose and 0-84 days after the second dose) compared with the remaining periods.Composite outcome of uveitis, scleritis, retinal vein occlusion (RVO), and optic neuritis.There were 99 718 pairs eligible for the matched cohort study after the first dose (mean age, 69.3 years; male, 44%). The vaccinated and control groups developed 29 and 21 events, respectively, over 21 days after the first dose, and 79 and 28 events, respectively, over 84 days after the second dose. The differences in cumulative incidence (reference, the control group) were 2.9 (95% confidence interval, -14.5 to 19.1) events/100 000 persons and 51.3 (16.2-84.3) events/100 000 persons, respectively, for the first and second doses. The SCCS study showed the IRRs of 0.89 (0.62-1.28) and 0.89 (0.71-1.11) for the first and second doses, respectively.The matched cohort analysis found an increased risk for the composite outcome after the second dose; however, the SCCS analysis showed no increased risk. Considering that the SCCS can cancel out time-invariant confounders, the current results suggest that COVID-19 vaccination is unlikely to causally increase the risk of ocular adverse events.Proprietary or commercial disclosure may be found after the references.

In die-casting and injection molding, a conformal cooling channel is applied inside the dies and molds to reduce the cycle time. When the internal face of the channel is rough, both cooling performance and tool life are negatively affected. Many methods for finishing the internal face of such channels have been proposed. However, the effects of the channel diameter on the flow of a low-viscosity finishing media and its finishing characteristics for H13 steel have not yet been reported in the literature. This study addresses these deficiencies through the following: the fluid flow in a channel was computationally simulated; the flow behavior of abrasive grains was observed using a high-speed camera; and the internal face of the channel was finished using the flow of a fluid containing abrasive grains. The flow velocity of the fluid with the abrasive grains increases as the channel diameter decreases, and the velocity gradient is low throughout the channel. This enables reduction in the surface roughness for a short period and ensures uniform finishing in the central region of the channel; however, over polishing occurs owing to the centrifugal force generated in the entrance region, which causes the form accuracy of the channel to partially deteriorate. The outcomes of this study demonstrate that the observational finding for the finishing process is consistent with the flow simulation results. The flow simulation can be instrumental in designing channel diameters and internal pressures to ensure efficient and uniform finishing for such channels.

Gyro finishing, which is one of the mass finishing, is expected to be an excellent finishing process of a workpiece with a complex shape. However, its fundamental researches are few, and hence the development of techniques to address its issues/problems, such as the decline of shape accuracy and low process controllability, is hindered by a lack of understanding of the process. Thus, a fundamental investigation of gyro finishing is conducted in the present research. The contact force acting on a cylindrical workpiece, which was designated by simplifying a large gear, was measured under different conditions in workpiece position, amount of abrasive media, and rotational speed of the container. In addition, the abrasive media height above the workpiece was measured, and effects of various factors on the contact force were investigated. From the results, the height above the workpiece was confirmed to have a strong correlation with the contact force. This was considered to be caused by increasing of the resistance of the abrasive media motion, and it was considered a major factor of the contact force. On the other hand, the effect of the abrasive media momentum and the distance between the workpiece and the container wall on the contact force was confirmed weak. Moreover, the variation of the surface roughness was investigated under different contact force conditions, and the improving speed of the surface roughness was faster under the higher contact force condition. Thus, contact force was a significant factor affecting the finishing performance, and this investigation featuring the contact force acting on the workpiece was considered significant to understand the gyro finishing process and to increase the contact force and the finishing performance.