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BACKGROUND: To study the 5-year changes in the posterior corneal surface after small incision lenticule extraction (SMILE) for high myopia. METHODS: Eighty eyes received SMILE was included in this prospective study. They were allocated into two groups based on the spherical equivalent: high myopia (40eyes, -7.49 ± 0.70D) and moderate myopia (40eyes, -4.43 ± 0.87D). Certain points of posterior corneal elevation (the central point (PCE), thinnest point (PTE), maximal point (PME), and in various corneal areas) were evaluated using a Scheimpflug camera (Pentacam; Oculus GmbH, Germany) preoperatively and at 6 months and 5 years after surgery. RESULTS: All surgeries were completed uneventfully and no ectasia was developed throng the observation. The safety index and efficacy index were 1.14 and 1.03 in the high myopia group, and 1.16 and 1.06 in the moderate myopia group, respectively. Most of the calculated values in the high myopia group showed a slight increase at 6 months but decreased at 5 years. At 5 years postoperatively, the value of the PTE was significantly lower than at baseline in both groups (P ≤ 0.047); a statistical difference was also revealed in the PME in the moderate group with slight changes (10.15 ± 3.01 µm vs. 11.60 ± 4.33 µm, P = 0.002); no statistical significance was observed in other calculated values (P ≥ 0.067). Similarly, no significant linear correlation was noted between changes in all values and the residual bed thickness either (P ≥ 0.057). CONCLUSIONS: SMILE causes no protrusion in posterior corneal surface for correction of high myopia at the follow-up visit of 5 years.
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Cirurgia da Córnea a Laser , Miopia , Topografia da Córnea , Humanos , Miopia/cirurgia , Estudos Prospectivos , Acuidade VisualRESUMO
Rapid and accurate determination of soil nitrogen supply capacity by detecting nitrogen content plays an important role in guiding agricultural production activities. In this study, near-infrared hyperspectral imaging (NIR-HSI) combined with two spectral preprocessing algorithms, two characteristic wavelength selection algorithms and two machine learning algorithms were applied to determine the content of soil nitrogen. Two types of soils (laterite and loess, collected in 2020) and three types of nitrogen fertilizers, namely, ammonium bicarbonate (ammonium nitrogen, NH4-N), sodium nitrate (nitrate nitrogen, NO3-N) and urea (urea nitrogen, urea-N), were studied. The NIR characteristic peaks of three types of nitrogen were assigned and regression models were established. By comparing the model average performance indexes after 100 runs, the best model suitable for the detection of nitrogen in different types was obtained. For NH4-N, R2p = 0.92, RMSEP = 0.77% and RPD = 3.63; for NO3-N, R2p = 0.92, RMSEP = 0.74% and RPD = 4.17; for urea-N, R2p = 0.96, RMSEP = 0.57% and RPD = 5.24. It can therefore be concluded that HSI spectroscopy combined with multivariate models is suitable for the high-precision detection of various soil N in soils. This study provided a research basis for the development of precision agriculture in the future.
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Nitrogênio , Solo , Imageamento Hiperespectral , Análise dos Mínimos Quadrados , Nitrogênio/análise , Solo/química , Espectroscopia de Luz Próxima ao Infravermelho/métodosRESUMO
This study used visible/near-infrared hyperspectral imaging (HSI) technology combined with chemometric methods to assess the freshness of pearl gentian grouper. The partial least square discrimination analysis (PLS-DA) and competitive adaptive reweighted sampling-PLS-DA (CARS-PLS-DA) models were used to classify fresh, refrigerated, and frozen-thawed fish. The PLS-DA model achieved better classification of fresh, refrigerated, and frozen-thawed fish with the accuracy of 100%, 96.43%, and 96.43%, respectively. Further, the PLS regression (PLSR) and CARS-PLS regression (CARS-PLSR) models were used to predict the storage time of fish under different storage conditions, and the prediction accuracy was assessed using the prediction correlation coefficients (Rp2), root mean squared error of prediction (RMSEP), and residual predictive deviation (RPD). For the prediction of storage time, the CARS-PLS model presented the better result of room temperature (Rp2 = 0.948, RMSEP = 0.255, RPD = 4.380) and refrigeration (Rp2 = 0.9319, RMSEP = 1.188, RPD = 3.857), while the better prediction of freeze was by obtained by the PLSR model (Rp2 = 0.9250, RMSEP = 2.910, RPD = 3.469). Finally, the visualization of storage time based on the PLSR model under different storage conditions were realized. This study confirmed the potential of HSI as a rapid and non-invasive technique to identify fish freshness.
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Imageamento Hiperespectral , Alimentos Marinhos , Animais , Análise dos Mínimos Quadrados , Perciformes , Espectroscopia de Luz Próxima ao Infravermelho , TecnologiaRESUMO
A new method for algal community restructuring is proposed, where harmful algae growth is inhibited through the addition of remedial nano-agent, while probiotic algae growth is promoted or only affected indistinctively. In this paper, the inhibiting effects of five different nanomaterials on Microcystis aeruginosa (M. aeruginosa) and Cyclotella sp. were studied, and the optimal nanomaterial was served as algae-inhibition ingredient of the remedial agent. The effects of the remedial agent on algal growth and their physiological characteristics were investigated, and the restructuring of algal community in actual water samples was explored. The results indicated that the inhibition ratio of 10 mg/L nm-Cu2O/SiO2 on M. aeruginosa and Cyclotella sp. could reach 293.1% and 82.8% respectively, acting as the best candidate for algae-inhibiting ingredient. After adding the remedial nano-agent made with nm-Cu2O/SiO2, the content of chlorophyll a, protein, and polysaccharides of M. aeruginosa decreased sharply, while the physiological characteristics of Cyclotella sp. were not significantly affected. Besides, the total biomass and proportion of cyanobacteria dropped (P < 0.05), but the Bacillariophyta biomass increased significantly (P < 0.05). The uniformity index, Shannon-Wiener index, and richness index all increased significantly (P < 0.05). Meanwhile, the quality of actual water samples has been improved evidently (P < 0.001). Therefore, the prepared remedial nano-agent in this study can control the harmful algae bloom to a certain extent by restructuring the algal community in eutrophic water bodies.
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Diatomáceas , Microcystis , Clorofila A , Proliferação Nociva de Algas , Dióxido de Silício , ÁguaRESUMO
Saffron has been applied in depression treatment, but its antidepressant compounds and mechanisms are unclear. In this research, a network pharmacology-based method was proposed to screen the active compounds and the potential mechanisms of saffron for depression treatment. Firstly, the chemical compounds of saffron were collected from literature and filtered by drug-like prediction. Secondly, common targets, by comparing the targets of saffron predicted by Pharm Mapper server with targets associated with depression collected from Genecards, were regarded as the antidepressant targets of saffron. Thirdly, common targets were mapped to KEGG pathways, considered as the pathways related with the antidepressant effects of saffron. Finally, the network of compounds-targets-pathways was constructed and analyzed by cytoscape 3.4.0. Ten compounds including crocetin, picrocrocin, (1R, 5S, 6R)-5-(hydroxymethyl)- 4, 4, 6-trimethyl-7-Oxabicyclo[4.1.0]heptan-2-one and its glycoside were screened as the main antidepressant compounds, some of which were reported for the first time. They might have effective treatment for depression by acting on targets, such as MAP2K1, MAPK1, HRAS, PIK3R1, ALB and AKT1 and pathways related with immune system, signal transduction and so on. This study provided a new insight into the antidepressant mechanism and active compounds of saffron, which also had a guiding effect on later experiments.
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Antidepressivos/farmacologia , Crocus/química , Flores , Farmacologia em Rede , Albuminas/efeitos dos fármacos , Albuminas/metabolismo , Carotenoides/química , Classe Ia de Fosfatidilinositol 3-Quinase/efeitos dos fármacos , Classe Ia de Fosfatidilinositol 3-Quinase/metabolismo , Cicloexenos/química , Glucosídeos/química , Humanos , MAP Quinase Quinase 1/efeitos dos fármacos , MAP Quinase Quinase 1/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais/efeitos dos fármacos , Terpenos/química , Vitamina A/análogos & derivados , Vitamina A/químicaRESUMO
BACKGROUND: Cycloplegics have been reported to induce changes in the lens thickness. However, the studies of correlation between cycloplegia and the lens position are limited. This study aims to investigate changes in crystalline lens rise (CLR) and other anterior segment parameters after inducing cycloplegia with tropicamide. METHODS: In this consecutive case study, 39 children (20 boys and 19 girls; mean age, 9.51 ± 1.75 years, mean spherical equivalence [SE], - 1.9 ± 1.5 D) with low-to moderate myopia were examined using CASIA 2 both before and after 30 min of administering 5-cycles (each 5 min apart) of 0.5% tropicamide. Measurements included CLR, crystalline lens thickness (CLT), mean radius of curvature of the anterior/posterior surface of the lens (Rf_ave/Rb_ave), anterior chamber depth (ACD), anterior chamber width (ACW), and central corneal thickness (CCT). Correlations of CLT and CLR with ACD, SE, and age were assessed respectively. RESULTS: CLT and CLR decreased significantly after cycloplegia (p < 0.001 and p < 0.001, respectively); whereas CCT, ACD, and Rf_ave increased (p = 0.008, p < 0.001, p < 0.001, respectively). A positive correlation was found between CLR and SE (r = 0.565, p < 0.001). However, a negative correlation between ACD and CLR was found before and after cycloplegia (r = - 0.430, p = 0.006; r = - 0.342, p = 0.035, respectively). CONCLUSIONS: The crystalline lens appeared thinner and moved backward after cycloplegia. ACD increased mainly due to the backward movement of the crystalline lens. These results aid in elucidating the impact of crystalline lens changes during the process of accommodation.
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Cristalino , Miopia , Acomodação Ocular , Câmara Anterior , Criança , Feminino , Humanos , Masculino , Refração Ocular , TropicamidaRESUMO
PURPOSE: To investigate changes in objective disk halo size produced by a glare source after small incision lenticule extraction (SMILE) for myopia correction. METHODS: This prospective clinical study included 45 right eyes of 45 patients with a mean age of 25.40 ± 5.06 years and mean spherical equivalent (SE) of - 6.08 ± 1.90 diopters. Disk halo size was measured with a vision monitor before surgery and at postoperative 1 week and 3 months. Other information was collected, including age, SE, lenticule thickness, lenticule diameter, dark pupil, and pupillary response to light parameters (initial diameter; amplitude, latency, duration, and velocity of contraction; latency, duration, and velocity of dilation; and maximum, minimum, and average pupil size). RESULTS: Compared to preoperative values, disk halo size increased significantly at postoperative 1 week (P = 0.026) and returned to baseline at postoperative 3 months (P = 0.349). Preoperative disk halo size significantly correlated with SE (r = - 0.346, P = 0.020), minimum pupil size (r = 0.365, P = 0.014), and average pupil size (r = 0.310, P = 0.038). Disk halo size at postoperative 1 week was significantly correlated with age (r = 0.324, P = 0.030) and minimum pupil size (r = 0.297, P = 0.047). Disk halo size at postoperative 3 months was significantly correlated with lenticule diameter (r = - 0.362, P = 0.015), initial diameter (r = 0.311, P = 0.037), maximum pupil size (r = 0.312, P = 0.037), minimum pupil size (r = 0.440, P = 0.002), and average pupil size (r = 0.373, P = 0.012). CONCLUSIONS: After SMILE, disk halo size demonstrated a temporary increase and then returned to baseline.
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Substância Própria/cirurgia , Cirurgia da Córnea a Laser/métodos , Topografia da Córnea/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Acuidade Visual , Adolescente , Adulto , Substância Própria/diagnóstico por imagem , Feminino , Seguimentos , Ofuscação , Humanos , Masculino , Miopia/diagnóstico , Período Pós-Operatório , Estudos Prospectivos , Adulto JovemRESUMO
PURPOSE: To investigate 7-year changes in corneal densitometry (CD) and its influencing factors following small incision lenticule extraction (SMILE) for moderate to high myopia. METHODS: A total of 32 patients (52 eyes) with a mean spherical equivalent (SE) refraction of -6.30 ± 1.30 D who underwent SMILE were recruited for this prospective study. Pre- and postoperative CD and corneal aberrations were measured by an oculus Pentacam system, and patients were followed up to 7 years. The CD evolution over time and its influencing factors were explored. RESULTS: No complications were observed after SMILE. There was a significant time effect on postoperative CD ( P < 0.05). The CD values at the 0-to-2 and 2-to-6 mm of the anterior layer increased at the first day ( P < 0.05) and declined to baselines at 1 year postoperatively; after that, CD values at any zone and any corneal layer presented a decreasing trend over time (all P < 0.05). Multivariate analysis showed that postoperative CD was positively correlated with age and optical zone (OZ), whereas negatively correlated with SE, corrected distance visual acuity (CDVA), and corneal aberrations (higher-order aberrations, Coma0 and Coma90) (all P < 0.05). Generalized estimating equation revealed that age, SE, CDVA, OZ, and Coma0 were the main factors influencing postoperative CD values (all P < 0.05). CONCLUSION: CD manifested a long-term decreasing trend in moderate to high myopia treated with SMILE. Its main influencing factors are age, SE, CDVA, OZ, and Coma0.
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CLINICAL RELEVANCE: More than 6 million small-incision lenticule extraction (SMILE) procedures have been performed worldwide since 2011. Therefore, its long-term safety and efficacy should be investigated. BACKGROUND: This study aimed to evaluate 10-year refractive outcomes, corneal stability, axial length, and wavefront aberrations in patients who underwent SMILE to correct myopia. METHODS: Thirty two patients (32 eyes) who underwent SMILE-based myopic correction. Corrected distance visual acuity, uncorrected distance visual acuity, corneal stability, axial length, and wavefront aberrations were evaluated preoperatively and at 1 month and 1, 5, and 10 years postoperatively. RESULTS: At 10 years postoperatively, the safety and efficacy indices for the patients included in this study were 1.19 ± 0.21 and 1.04 ± 0.27, respectively. For 26 (81%) and 30 eyes (94%), correction to within ±0.50 D and ±1.00 D of the target was achieved, respectively. Over the 10-year follow-up duration, a mean -0.32 ± 0.56 D regression was observed (-0.03 ± 0.06 D/year). Relative to baseline, horizontal and vertical comas significantly increased, as did the incidence of higher-order aberrations (all P < 0.001), whereas axial length and corneal elevation remained stable during follow-up. CONCLUSION: These results indicate that the SMILE-based correction for myopia of up to -10 Dioptres is safe, effective, and stable, with relatively constant wavefront aberrations and corneal stability over time after treatment.
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Astigmatismo , Cirurgia da Córnea a Laser , Miopia , Humanos , Lasers de Excimer/uso terapêutico , Acuidade Visual , Refração Ocular , Miopia/cirurgia , Córnea/cirurgia , Substância Própria/cirurgia , Resultado do Tratamento , Cirurgia da Córnea a Laser/métodos , Astigmatismo/cirurgiaRESUMO
BACKGROUND: Hearing loss is a common sequala of Streptococcus suis (S. suis) meningitis, but few have addressed cochlear implantation (CI) candidates with S. suis meningitis. OBJECTIVES: To assess the clinical characteristics and CI postoperative outcomes in S. suis meningitis patients. MATERIAL AND METHODS: Eight S. suis meningitis patients underwent CI at Sun Yat-sen Memorial Hospital between 2020 and 2023. Control groups included (1) non-Suis meningitis patients (n = 12) and (2) non-meningitis patients (n = 35). Electrode impedances and neural response telemetry (NRT) thresholds were recorded at one month after surgery. The auditory performance-II (CAP) and speech intelligibility rating (SIR) were recorded at the last visit. RESULTS: CAP scores of S. suis meningitis patients were significantly lower than those of non-Suis meningitis and non-meningitis patients (p = .019; p<.001). And NRT thresholds of S. suis meningitis patients were higher than those of non-Suis meningitis and non-meningitis patients (p = .006; p = .027). CONCLUSIONS AND SIGNIFICANCE: It is recommended for S. suis meningitis CI candidates to undergo CI promptly after controlling infection, preferably within four to six weeks. CI users with S. suis meningitis tend to exhibit suboptimal hearing rehabilitation outcomes, possibly associated with the more severe damage on spiral ganglion cells after S. suis meningitis.
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Implante Coclear , Meningites Bacterianas , Infecções Estreptocócicas , Streptococcus suis , Humanos , Masculino , Feminino , Meningites Bacterianas/complicações , Adulto , Pessoa de Meia-Idade , Infecções Estreptocócicas/cirurgia , Infecções Estreptocócicas/complicações , Idoso , Adulto JovemRESUMO
AIM: To investigate the long-term changes of corneal densitometry (CD) and its contributing elements after small incision lenticule extraction (SMILE). METHODS: Totally 31 eyes of 31 patients with mean spherical equivalent of -6.46±1.50 D and mean age 28.23±7.38y were enrolled. Full-scale examinations were conducted on all patients preoperatively and during follow-up. Visual acuity, manifest refraction, axial length, corneal thickness, corneal higher-order aberrations, and CD were evaluated. RESULTS: All surgeries were completed successfully without complications or adverse events. Ten-year safety index was 1.17±0.20 and efficacy 1.04±0.28. CD value of 0-6 mm zones in central layer was statistically significantly lower 10y postoperatively, compared with preoperative values (0-2 mmΔ=-1.62, 2-6 mmΔ=-1.24, P<0.01). There were no correlations between CD values and factors evaluated. CONCLUSION: SMILE is a safe and efficient procedure for myopia on a long-term basis. CD values get lower 10y postoperatively, whose mechanism is to be further discussed.
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CLINICAL RELEVANCE: Orthokeratology (OK) lens is commonly used to control myopia progression of children. Understanding the relationship between relative peripheral refraction (RPR) and the growth rate of axial length (AL) may assist in explaining myopic progression. BACKGROUND: The aim of this work is to investigate the RPR in myopic children wearing OK lenses, and to evaluate its relationship with the growth rate of AL. METHODS: RPRs of 31 children wearing OK lenses and 31 children wearing single-vision glasses were measured with multispectral refraction topography (MRT). MRT shows the total RPR (TRPR), RPR in the superior area (RPR-S), RPR in the inferior area (RPR-I), RPR in the temporal area (RPR-T) and RPR in the nasal area (RPR-N), respectively. It also shows RPR in the visual field of 15° (RPR-15), 30° (RPR-30) and 45° (RPR-45), respectively. RPRs in the visual field from 15° to 30°, 30° to 45° and 15° to 45° are recorded as RPR-(30-15), RPR-(45-30) and RPR-(45-15), respectively. According to the growth rate of AL, children wearing OK lenses were further divided into slow and fast growth groups. RESULTS: TRPR, RPR-I, RPR-T, RPR-N, RPR-15, RPR-30, RPR-45, RPR-(30-15), RPR-(45-30), and RPR-(45-15) of children in the OK lens group were significantly smaller than in the control group (all P < 0.05). TRPR, RPR-N, RPR-15, RPR-30, RPR-45, RPR-(30-15), and RPR-(45-15) of the slow growth group were significantly smaller than in the fast growth group (all P < 0.05). The growth rate of AL were positively correlated with TRPR (R = 0.383, P = 0.040), RPR-N (R = 0.395, P = 0.034), RPR-30 (R = 0.408, P = 0.028), RPR-45 (R = 0.377, P = 0.044), RPR-(30-15) (R = 0.390, P = 0.036). CONCLUSIONS: RPRs of children show relative myopic defocus after wearing OK lenses. Furthermore, the growth rate of AL is smaller with more negative RPR.
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Miopia , Procedimentos Ortoceratológicos , Humanos , Criança , Refração Ocular , Miopia/terapia , Testes Visuais , Óculos , Comprimento Axial do Olho , Topografia da CórneaRESUMO
To study the high-temperature mechanical properties of potassium magnesium phosphate cement mortar and the high-temperature resistance of its laminates. Potassium magnesium phosphate cement (MKPC) was prepared by using heavy-burning magnesium oxide and potassium dihydrogen phosphate as the main raw materials, borax as the retarder, and compounded with a certain amount of fly ash and silica fume. The effect of the mass ratio of magnesium to phosphorus (M:P), compounded fly ash and silica fume on the setting time and mechanical properties of MKPC was investigated. Furthermore, based on the better M:P, the compressive strength of MKPC mortar was studied after 3 h of constant temperature at 400 °C, 600 °C, and 800 °C, and the effect of fly ash and silica fume on the high-temperature resistance of MKPC was analyzed. The high-temperature resistance of MKPC was further evaluated by analyzing the temperature variation of potassium magnesium phosphate cement laminate during a constant temperature of 650 °C for 3 h. The results showed that the mechanical properties of potassium magnesium phosphate cement were influenced by different raw material ratios, and the mechanical properties of potassium magnesium phosphate cement were optimal when M:P was 2:1, fly ash was 5% and silica fume was 15%. The internal temperature of MKPC laminate increased slowly with time, and its high-temperature resistance was better.
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PURPOSE: To evaluate the changes in posterior corneal elevation in thin corneas after small incision lenticule extraction (SMILE). METHODS: In this prospective study, 97 eyes of 97 patients undergoing SMILE were recruited. Eyes were categorized into the following groups based on the preoperative minimum central corneal thickness (CCT): group A (37 eyes, 480-499 µm), group B (30 eyes, 500-529 µm), and group C (30 eyes, 530-560 µm). The posterior corneal surface was measured with a Pentacam over a 3-year follow-up period. Changes in the posterior corneal elevation at the central point (PCE), thinnest point (PTE), and predetermined area were measured. RESULTS: No iatrogenic keratectasia was observed during the follow-up period. The mean changes in PCE, PTE, and the inferior area in group A were 1.14 ± 3.40 µm, -0.11 ± 3.20 µm, and -0.26 ± 1.23 µm, respectively (P ≥ 0.125). Although statistically significant change in the central-4 mm area was noted, the value was quite small (0.98 ± 1.67 µm) and was not higher than that in the other two groups (P = 0.003). For all three groups, the elevation remained stable or showed a backward change in the central annulus, while there was a small forward displacement in the 6-mm optical zone. In group A, changes in elevation values yielded negative statistical correlations with residual bed thickness and CCT (P ≤ 0.006) (except for the inferior area, the 4-mm and 6-mm optical zone). CONCLUSIONS: With a strict preoperative assessment, SMILE achieved good safety and efficacy in correcting myopia in thin corneas and enabled a stable posterior corneal surface over a 3-year follow-up period. SYNOPSIS: Careful preoperative assessment and suitable surgical design should be taken to ensure posterior corneal stability after SMILE in thin corneas.
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PURPOSE: To explore the influence of two different incision positions of small incision lenticule extraction (SMILE) on astigmatism correction. METHODS: A total of 86 eyes of 86 patients who underwent SMILE surgery were included in this retrospective study. The criteria included that the preoperative astigmatism axis to be within 165° to 180° or 5° to 15°. All eyes were divided into two groups according to the incision position. The incisions of 34 eyes were either located on the superior temporal side of the right eye or superior nasal side of the left eye (120° group), and 52 eyes were located on the superior side (90° group). Vector analysis was used to analyze pre- and postoperative 3-month astigmatism, while subgroup analysis was applied according to the preoperative astigmatism. RESULTS: No significant difference of preoperative parameters was found between the two groups (P > 0.05). The efficacy and safety indexes were 1.11 ± 0.16 and 1.15 ± 0.16 in the 120° group, the numbers were 1.15 ± 0.17 and 1.16 ± 0.14 in the 90° group (P = 0.629 and P = 0.871). There was no significant difference in target-induced astigmatism (TIA), TIA axis, surgically induced astigmatism (SIA) magnitude, SIA axis, distance vision (DV) magnitude, DV axis, correction index (CI), angle of error (AofE), |AofE|, magnitude of error (MofE), index of success (IOS), or flattening index (FI) between 120° group and 90° group (P > 0.05). No significant difference was found in the subgroup analysis (P > 0.05). CONCLUSIONS: The incision position has limited astigmatic effect, and the operation-induced astigmatism of SMILE surgery after 3 months was little.
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Purpose: To evaluate the outcomes in corneal higher-order aberrations (HOAs) and microdistortions in the Bowman's layer after femtosecond laser small incision lenticule extraction (SMILE) for correcting extremely high myopia. Methods: This prospective study included patients with myopia with spherical equivalent ≥ -9.0 Diopters (D). SMILE was performed in forty eyes of 40 patients. Pentacam was used to evaluate HOAs before and at 1 day, 3 months, 6 months, and 2 years after surgery. Fourier-domain optical coherence tomography was used to evaluate microdistortions at 2 years postoperatively. Thirty-two eyes of 32 patients receiving femtosecond laser-assisted in situ keratomileusis (FS-LASIK) were enrolled as the control group. HOAs were measured before, at 1 day and at least 1 year postoperatively. Results: After SMILE, the long-term safety and effectiveness index was 1.25 and 0.85, respectively. Microdistortions were observed in 73.5% of the eyes at 2 years, with an average number of 1.20 ± 1.22 microdistortions and an average width of 287.37 ± 259.00 µm. We detected more microdistortions in the horizontal meridian than in the vertical meridian (p = 0.035). The average number and width of microdistortions were both higher in the central region (≤4 mm) than in the peripheral region (4-8 mm) (both p < 0.001). With the exception of horizontal trefoil in the SMILE group and vertical trefoil in the FS-LASIK group, significant changes over time were observed in all other HOAs (all p < 0.05). Meanwhile, we detected significant increases in the total corneal HOA, spherical aberration (SA), and coma at all time-points after both surgeries (all p < 0.01). Compared with FS-LASIK, SMILE induced less SA (p < 0.001) and more horizontal coma (p = 0.036). In the SMILE group, the HOA, SA, and trefoil were more in the small optical zone (≤6.0 mm) than in the large optical zone (>6.0 mm) (all p < 0.05). The increase in SA and most trefoil correlated with the mean number of central microdistortions number (all p < 0.05). Conclusion: For myopia over -9.0D, the microdistortions in the Bowman's layer were still detectable in most eyes long-term after SMILE. Both SMILE and FS-LASIK induced more HOAs, mainly HOA, SA, and coma. The small optical zone and microdistortions may affect postoperative aberrations.
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PURPOSE: To investigate the correlation between the change in spatial corneal power distribution and axial length (AL) elongation during orthokeratology (Ortho-k) treatment using mathematical methods. METHODS: Seventy-six subjects aged from eight to 13 years were fitted with Paragon CRT ortho-k lenses. Manifest refraction and corneal topography were checked at baseline and one day, one week, two weeks, one month, three months, six months, nine months, and one year after lens wear. AL was measured at baseline and the six-month and one-year follow-up visits. Relative corneal refractive power change (RCRPC) was calculated by a polynomial function and a monomial function. Factors including age, baseline spherical equivalent refractive error (SER), power exponent and RCRPC were tested against one-year AL growth in a stepwise multiple linear regression model. RESULTS: A total of 67 subjects completed the one-year study, with nine dropouts. The SER significantly reduced after the first month of lens wear (P < 0.001). AL significantly changed over time (P = 0.0003) with the annual growth being 0.32 ± 0.18 mm. Power exponent and RCRPC were stable throughout the follow-up visits (all P > 0.05). Change of AL was significantly correlated with baseline age (standardized ß = -0.292, P < 0.001) and power exponent (standardized ß = 0.691, P < 0.001), but not with the other factors being analyzed. The regression equation using baseline age (X1) and power exponent (X2) as functions for 1-year AL change (Y) was Y = 0.438-0.034X1 + 0.309X2, with R2 being 0.752. CONCLUSIONS: The asphericity of the treatment zone may affect axial elongation in children undergoing ortho-k therapy. TRANSLATIONAL RELEVANCE: Because the ortho-k lens design may affect myopia control effect in children undergoing ortho-k therapy, future ortho-k lenses should consider applying these designs to obtain a better myopia control effect in children.
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Miopia , Procedimentos Ortoceratológicos , Criança , Córnea , Topografia da Córnea , Humanos , Miopia/diagnóstico , Miopia/terapia , Refração OcularRESUMO
PURPOSE: To investigate the feasibility and safety of the implantable collamer lens V4c (ICL V4c) implantation without using an ophthalmic viscosurgical device (OVD-free technique). METHODS: This prospective consecutive case study enrolled 118 eyes of 60 patients (15 eyes were of male patients, 103 eyes were of female patients, age 26.19 ± 5.03 years, spherical equivalent -10.05 ± 2.73 D). Eyes were considered for OVD-free or OVD-using ICL V4c implantation based on the maintenance of the anterior segment during the surgery. The follow-up lasted for 12 months. The main measurements were visual acuity and changes in endothelial cell density (ECD) at 12 months. RESULTS: A total of 75 eyes were included in the OVD-free group and 43 in the OVD group. No infection or other complications were observed in any eye. In the OVD-free group, the safety and efficacy indices were 1.19 ± 0.15 and 1.05 ± 0.20, respectively. 74.5% of the eyes gained one or two lines of corrected distance visual acuity (CDVA), and 25.5% were stable. In the OVD group, the safety and efficacy indices were 1.17 ± 0.17 and 1.03 ± 0.15, respectively; 65.7% of the eyes gained one or two lines of CDVA, and 34.3% were stable. The mean change of ECD was 65.34 cell/ mm2 compared to the baseline in the OVD-free group and 25.94 cell/ mm2 compared to baseline in the OVD group (P = 0.038). CONCLUSIONS: The ICL V4c implantation with an OVD-free technique is a safe and feasible method in eyes with good maintenance of the anterior segment.
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A terahertz (THz) metamaterial absorber based on a split ring resonator (SRR) structure was used to realize the highly accurate detection of trace pesticides, including indole-3-acetic acid (IAA) and tricyclazole. The density functional theory (DFT) was used to analysis the THz fingerprint peaks of IAA and tricyclazole. According to the dual-band (0.918 and 1.575 THz) near-perfect absorption characteristics of the absorber in the transverse magnetic (TM) polarization state, the univariate regressions were used to analyze the responses of peak amplitude and frequency to pesticide concentrations. For IAA, the sensing response based on the peak amplitude at 1.575 THz was the best with a coefficient of determination (R2) of 0.9627. As for tricyclazole, the best sensing response was based on the peak frequency at 1.575 THz with a R2 of 0.8742. Moreover, the detection accuracy of IAA (R2 = 0.9752) and tricyclazole (R2 = 0.9177) were significantly improved through effective variable selection and multivariate fusion. The results indicated that the limit of detection (LOD) of two pesticides both reached 10 ng/L. This study provided a good experimental basis for trace hazardous substances detection, presenting a new prospect for food quality and safety control in the future.
Assuntos
Ácidos Indolacéticos , Praguicidas , TiazóisRESUMO
PURPOSE: To investigate the long-term changes in posterior corneal elevation in moderate and high myopia after small-incision lenticule extraction (SMILE). SETTING: Eye & ENT Hospital, Fudan University, Shanghai, China. DESIGN: Prospective case series. METHODS: 33 eyes of 20 patients (30.1 ± 9.5 years, 7 men and 13 women, spherical equivalent [SE] range -4.00 to -8.75 D, mean SE -6.25 ± 1.29 D) who underwent SMILE were included. Changes in the posterior corneal elevation at central points (PCE), the thinnest point (PTE), the maximal point (PME), and an additional 20 points within the 4 mm area of the best-fit sphere were evaluated with a Pentacam (Oculus Optikgeräte GmbH) during a 7-year follow-up period. Mixed linear models were used to evaluate changes with P values less than 0.05. Correlations of elevation changes and residual bed thickness (RBT) were also evaluated. RESULTS: No ectasia was observed among the 33 eyes studied. The safety index was 1.08, and the efficacy index was 1.03. The mean change in PCE at 1 year, 3 years, 5 years, and 7 years was -1.42 ± 0.95 µm, -2.67 ± 0.98 µm, -2.44 ± 1.06 µm, and -1.91 ± 0.92 µm, respectively. Statistically significant differences were found at 3 years, 5 years, and 7 years (P = .007, .023, and .040, respectively). PTE reduced significantly at each time point compared with baseline. The mean change was -2.82 ± 1.19 µm, -3.55 ± 1.22 µm, -3.47 ± 1.32 µm, and -2.39 ± 1.15 µm, respectively (P = .019, .004, .010, and .039, respectively). PME changed in 2.45 ± 1.02 µm at 7 years compared with baseline (P = .017). The changes in PCE and PME negatively correlated with the RBT. CONCLUSIONS: Long-term posterior corneal elevation was stable in moderate and high myopia after SMILE.