Add-On Effect of 0.01% Atropine in Orthokeratology Wearers for Myopia Control in Children: A 2-Year Retrospective Study.

INTRODUCTION: Orthokeratology (OK) and low-concentration atropine are recommended approaches for controlling myopia. However, children with younger age and lower myopia are more likely to experience rapid axial progression during OK or atropine monotreatment. This study aimed to assess the efficacy of OK combined with low-concentration atropine for myopia control in children over 24 months and to determine whether the effect was sustainable. METHODS: In this retrospective study, we reviewed medical records of baseline and follow-up visits from children (7-14 years) applying OK for myopia control. Sixty-eight children receiving monoorthokeratology treatment (OK group) and 68 children who received 0.01% atropine in combination with orthokeratology simultaneously (AOK group) were included. A series of ophthalmic tests at baseline were conducted, and axial length (AL) was measured every 6 months. The comparison of AL change at different visits between the two groups was performed by repeated measures multivariate analyses of variance (RM-MANOVA). RESULTS: There were no significant differences in baseline characters between the two groups (p > 0.05). The AL significantly increased over time in both groups (all p < 0.05), and the 2-year change in AOK was 0.16 mm (36%) lower than in OK (0.28 ± 0.22 mm versus 0.44 ± 0.34 mm, p = 0.001). Compared with OK group, the significant suppression of AL elongation in the AOK group was observed in 0-6, 6-12, and 12-18 month periods (suppression rate: 62.5%, 33.3%, 38.5%, respectively, p < 0.05), while there was no significant difference in the 18-24 month period (p = 0.105). The multiple regression analysis showed an interaction between age and treatment effect (interaction coefficient = 0.06, p = 0.040), indicating one year age decrease approximately associated with 0.06 mm increased retardation in AL elongation in the AOK group. CONCLUSION: The add-on effect of 0.01% atropine in OK wearers only occurred within 1.5 years, and younger children benefited more from the combination treatment.

Ratiometric and visual determination of copper ions with fluorescent nanohybrids of semiconducting polymer nanoparticles and carbon dots.

Developing nanohybrid composition based fluorescent carbon dots (CDs) for ratiometric detection of copper ions is highly appealing. Herein, a ratiometric sensing platform (GCDs@RSPN) for copper ions detection has been developed by loaded green fluorescence carbon dots (GCDs) on the surface of red emission semiconducting polymer nanoparticles (RSPN) through electrostatic adsorption. The GCDs, featuring abundant amino groups, can selectively bind copper ions to induce the photoinduced electron transfer, leading to fluorescence quenching. A good linearity within the range of 0-100 µM is obtained, and the limit of detection (LOD) is 0.577 µM by using obtained GCDs@RSPN as ratiometric probe to detect copper ion. Moreover, the paper-based sensor derived from GCDs@RSPN was successfully applied for the visual detection of Cu2+.

Changes of corneal biomechanics in children using orthokeratology and their roles in predicting axial length progression-A prospective 2-year study.

PURPOSE: To determine how orthokeratology (ortho-k) affects corneal biomechanical properties in myopia control and whether corneal biomechanical parameters can predict clinical efficacy of ortho-k. METHODS: A total of 125 children 7-15 years of age using ortho-k lenses were followed in this clinical practice and data of their right eyes were analysed. Corneal biomechanical parameters and most ocular biometry were measured at baseline, 1 week, and at 1, 3, 6, 12, 18 and 24 months. Axial length (AL) was collected every 6 months after baseline measurements. RESULTS: During the 2-year follow up, nine corneal biomechanical parameters, including deformation amplitude maximum (DA), varied between baseline and 1 week (p < 0.05) and stabilized during the rest of wearing period (p > 0.05). The mean AL increased from 25.02 ± 0.84 mm to 25.38 ± 0.81 mm and baseline DA strongly correlated with AL progression (Pearson r = 0.37). In the multiple regression models, baseline age, AL and DA were the independent factors for AL progression (R2 : 0.7849, 0.2180 in low and moderate myopes). The area under the receiver operating characteristic curves using the three variables for predicting excessive AL progression (>0.35 mm during 2 years) in low and moderate myopes was 0.902 and 0.698. CONCLUSIONS: Corneal biomechanics firstly fluctuated before becoming stable with long-term ortho-k use. Corneal biomechanics was associated with AL progression in children wearing ortho-k lenses. DA combined with age and AL at baseline could predict AL progression in low myopes using ortho-k.

Clinical and Microbiological Characteristics of Endogenous Klebsiella pneumoniae Endophthalmitis in a Tertiary Hospital in Shanghai, China.

PURPOSE: To investigate the clinical features of endogenous Klebsiella pneumoniae endophthalmitis (EKPE) and the molecular characteristics of pathogenic K. pneumoniae. METHODS: A retrospective study was conducted between January 2014 and January 2021. Clinical data were extracted. K. pneumoniae isolates cultured from EKPE patients' specimens were characterized by antimicrobial susceptibility testing, multilocus sequence typing, capsular serotyping, and virulence gene profiles. Virulence phenotypes were confirmed by mouse lethality assay. RESULTS: Thirty-nine patients (47 eyes) were diagnosed with EKPE. Administration of systemic antibiotics and eye treatment within 24 hours of ocular symptom onset was statistically associated with better visual outcomes (p = .007). Sixteen K. pneumoniae isolates were collected, three of which were carbapenem-resistant and avirulent. Only salmochelin encoding gene was harbored by all isolates. CONCLUSIONS: Systemic and eye treatment administered within 24 hours from the onset improves visual prognosis. Besides hypervirulent strains, avirulent carbapenem-resistant K. pneumoniae can cause EKPE.

Refinement method for compressive hyperspectral data cubes based on self-fusion.

Compressive hyperspectral images often suffer from various noises and artifacts, which severely degrade the imaging quality and limit subsequent applications. In this paper, we present a refinement method for compressive hyperspectral data cubes based on self-fusion of the raw data cubes, which can effectively reduce various noises and improve the spatial and spectral details of the data cubes. To verify the universality, flexibility, and extensibility of the self-fusion refinement (SFR) method, a series of specific simulations and practical experiments were conducted, and SFR processing was performed through different fusion algorithms. The visual and quantitative assessments of the results demonstrate that, in terms of noise reduction and spatial-spectral detail restoration, the SFR method generally is much better than other typical denoising methods for hyperspectral data cubes. The results also indicate that the denoising effects of SFR greatly depend on the fusion algorithm used, and SFR implemented by joint bilateral filtering (JBF) performs better than SRF by guided filtering (GF) or a Markov random field (MRF). The proposed SFR method can significantly improve the quality of a compressive hyperspectral data cube in terms of noise reduction, artifact removal, and spatial and spectral detail improvement, which will further benefit subsequent hyperspectral applications.

Photopic pupil size change in myopic orthokeratology and its influence on axial length elongation.

AIM: To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology (ortho-k) over 1-year period and its effects on the axial elongation. METHODS: A total of 202 Chinese myopic children were enrolled in this prospective clinical trial. Ninety-five subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study. Axial length (AL) was measured before enrollment and every 6mo after the start of ortho-k. The photopic pupil diameter (PPD) was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx. Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation. RESULTS: Compared with spectacle group, the average 1-year axial elongation was significantly slower in the ortho-k group (0.25±0.27 vs 0.44±0.23 mm, P<0.0001). In ortho-k group, PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear (P=0.001, Bonferroni correction) and the change lasts for 3-month visit. No significantly change during the other follow-up visits was found (P>0.05, Bonferroni correction). The 4.81 mm PPD may be a possible cutoff point in the ortho-k group. Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period (t=-3.09, P=0.003). In ortho-k group, univariate analyses indicated that those with older age, greater degree of myopia, longer AL, smaller baseline PPD (PPDbaseline) experienced a smaller change in AL. In multivariate analyses, older age, greater AL and smaller PPDbaseline were associated with smaller increases in AL. In spectacle group, PPD tended to be stable (P>0.05, Bonferroni correction) and did not affect axial growth. CONCLUSION: PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment. Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.

Practical generation of arbitrary high-order cylindrical vector beams by cascading vortex half-wave plates.

A practical direct-view scheme for generating arbitrary high-order cylindrical vector (HCV) beams by cascading vortex half-wave plates (VHPs) is presented. The combination of odd number 2n-1 VHPs for n≥1 can realize (m2n-1-m2n-2+…+m1)-order CV beams, in which m is the order number of VHP and the corresponding subscript 2n-1 represents the arrangement number of VHPs, and the cascading of even number 2n ones can obtain (m2n-m2n-1+…+m2-m1)-order CV beams. All 1-12 order CV beams, including the high-order anti-vortex CV (ACV) beams, are generated only by selectively cascading the VHPs with m=1, 3 and 8. The polarization properties of the generated HCV beams are investigated by measuring the corresponding Stokes parameters. It is experimentally demonstrated that arbitrary HCV beams are effectively achieved by the proposed method. The order numbers of CV beams can be greatly expanded by cascading limited types of VHPs.

Crystalline Lens Power and Associated Factors in Highly Myopic Children and Adolescents Aged 4 to 19 Years.

PURPOSE: To investigate the distribution characteristics of lens power in highly myopic Chinese children and adolescents and its association with age, axial length (AL), and spherical equivalent (SE). DESIGN: Cross-sectional study. METHODS: A total of 459 highly myopic (SE ≤-5 diopter [D]) children and adolescents aged 4-19 years were included in the study. Participants underwent a series of ophthalmic examinations, which included AL, cycloplegic refraction, and Pentacam measurements. Lens power was calculated using Bennett's formula with its distribution described by age, AL, and SE. Multiple regression was conducted to analyze the associated factors of lens power. RESULTS: Greater lens power was independently associated with younger age, girls, shorter AL, and thicker lens thickness (standardized ß = -0.203, 0.214, -0.379 and 0.492, respectively; all P < .001). However, a significant difference in lens power with age was only found in participants younger than 9 years, after which it reached a plateau (mean difference of 1.23 and 0.084 D per age group, respectively). Lens power was negatively associated with AL only in participants with AL <27 mm. No correlation was observed between lens power and SE. CONCLUSION: Among highly myopic children and adolescents, differences in lens power with age declined significantly after 9 years of age, which was 1 year earlier than non-high myopic patients in previous studies, which implied differences in pathophysiological process between non-high myopia and high myopia. The decoupling of lens power and AL in eyes >27 mm might represent the limited influence of AL on lens power.

Single-shot coherent power-spectrum imaging of objects hidden by opaque scattering media.

We report coherent imaging of objects behind opaque scattering media with only one piece of the power spectrum pattern. We solve the unique solution and improve algorithm speed for the inverse problem. Based on the proposed scattering-disturbance model, with only one piece of the Fourier transform power spectrum pattern under coherent illumination, we successfully reconstruct clear images of the objects fully hidden by an opaque diffuser. The experimental results demonstrate the feasibility of the reconstruction method and the scattering-disturbance model. Our method makes it possible to carry out snapshot coherent imaging of the objects obscured by scattering media, which extends the methodology of x-ray crystallography to visible-light scattering imaging for underwater and living biomedical imaging.

Prevalence and associated risk factors of undercorrected refractive errors among people with diabetes in Shanghai.

BACKGROUND: To investigate the prevalence and risk factors of undercorrected refractive error (URE) among people with diabetes in the Baoshan District of Shanghai, where data for undercorrected refractive error are limited. METHODS: The study was a population-based survey of 649 persons (aged 60 years or older) with diabetes in Baoshan, Shanghai in 2009. One copy of the questionnaire was completed for each subject. Examinations included a standardized refraction and measurement of presenting and best-corrected visual acuity (BCVA), tonometry, slit lamp biomicroscopy, and fundus photography. RESULTS: The calculated age-standardized prevalence rate of URE was 16.63% (95% confidence interval [CI] 13.76-19.49). For visual impairment subjects (presenting vision worse than 20/40 in the better eye), the prevalence of URE was up to 61.11%, and 75.93% of subjects could achieve visual acuity improvement by at least one line using appropriate spectacles. Under multiple logistic regression analysis, older age, female gender, non-farmer, increasing degree of myopia, lens opacities status, diabetic retinopathy (DR), body mass index (BMI) index lower than normal, and poor glycaemic control were associated with higher URE levels. Wearing distance eyeglasses was a protective factor for URE. CONCLUSION: The undercorrected refractive error in diabetic adults was high in Shanghai. Health education and regular refractive assessment are needed for diabetic adults. Persons with diabetes should be more aware that poor vision is often correctable, especially for those with risk factors.

The control effect of orthokeratology on axial length elongation in Chinese children with myopia.

BACKGROUND: To retrospectively compare axial elongation in children with different degrees of myopia wearing spectacles and undergoing ortho-k treatment. METHODS: The medical records of 128 patients who were fitted with spectacles or orthokeratology (ortho-k) lenses in our clinic between 2008 and 2009 were reviewed. Ortho-k group comprised 65 subjects and 63 subjects wearing spectacles were included in the control group. Subjects were also divided into low-myopia, moderate-myopia and high-myopia groups, based on the basic spherical equivalent refractive error. Axial length periodically measured over 2-year of lens wear and changes in axial length were compared between treatment groups and between subgroups with different degrees of myopia. RESULTS: The control group exhibited more changes in axial length than the ortho-k group at both 12 months (0.39 ± 0.21 mm vs 0.16 ± 0.17 mm, p <0.001) and 24 months (0.70 ± 0.35 mm vs 0.34 ± 0.29 mm, p <0.001). Axial length elongation was estimated to be slower by about 51% in the ortho-k group. Similar results were found for the subgroups (49%, 59% and 46% reductions, respectively). In the group with low and moderate myopia, the annual increases in axial length were significantly different between the ortho-k and control groups during both the first ( Low myopia: 0.19 ± 0.17 mm vs 0.40 ± 0.18 mm, p = 0.001; Moderate myopia: 0.14 ± 0.18 mm vs 0.45 ± 0.22 mm, p <0.001) and second ( Low myopia: 0.18 ± 0.14 mm vs 0.32 ± 0.19 mm, p = 0.012; Moderate myopia: 0.18 ± 0.16 mm vs 0.34 ± 0.30 mm, p = 0.030) years. In the high myopia groups, significant differences were only found between the ortho-k and control groups during the first year (0.16 ± 0.18 mm vs 0.34 ± 0.22 mm, p = 0.004). The 2-year axial elongation was significantly associated with initial age (p <0.001) and treatment (p <0.001), but not with gender, initial refractive error, initial axial length, initial corneal curvature. CONCLUSIONS: This 2-year study indicates that ortho-k contact lens wear is effective for reducing myopia progression in children with low, moderate and high myopia.

Three-dimensional shape-controllable focal spot array created by focusing vortex beams modulated by multi-value pure-phase grating.

We propose a method for creating a three-dimensional (3D) shape-controllable focal spot array by combination of a two-dimensional (2D) pure-phase modulation grating and an additional axial shifting pure-phase modulation composed of four-quadrant phase distribution unit at the back aperture of a high numerical aperture (NA) objective. It is demonstrated that the one-dimensional (1D) grating designed by optimized algorithm of selected number of equally spaced arbitrary phase value in a single period could produce desired number of equally spaced diffraction spot with identical intensity. It is also shown that the 2D pure-phase grating designed with this method could generate 2D diffraction spot array. The number of the spots in the array along each of two dimensions depends solely on the number of divided area with different phase values of the dimension. We also show that, by combining the axial translation phase modulation at the back aperture, we can create 3D focal spot array at the focal volume of the high NA objective. Furthermore, the shape or intensity distribution of each focal spot in the 3D focal array can be manipulated by introducing spatially shifted multi vortex beams as the incident beam. These kinds of 3D shape-controllable focal spot array could be utilized in the fabrication of artificial metamaterials, in parallel optical micromanipulation and multifocal multiphoton microscopic imaging.

[The impact of amplitude of accommodation on controlling the development of myopia in orthokeratology].

OBJECTIVE: To evaluate the impact of amplitude of accommodation on controlling the development of myopia in orthokeratology. METHODS: Forty-nine children aged 7 to 14 years were enrolled in this prospective clinical study.Orthokeratology was performed to correct the refractive errors of these children after measurement of refraction, corneal topography, amplitude of accommodation and axial length. Axial length (AL) and amplitude of accommodation was measured after treatment. The average amplitude of accommodation was calculated and was used as the cutting point for dividing the cohort into "amplitude of accommodation above average" vs. "amplitude of accommodation below average". Data were analyzed by paired t-test, independent t-test, repeated measures-ANOVAs and Pearson correlation analysis. RESULTS: The AL before and after 1- year and 2-year treatment was (24.98 ± 0.75) mm, (25.13 ± 0.74) mm and (25.32 ± 0.78) mm, respectively. AL increased significantly throughout the observed 24-month period (F = 75.848, P < 0.001) . Amplitude of accommodation increased from (13.68 ± 2.65) D to (16.12 ± 2.41) D in 2 years (t = -6.461, P < 0.001) and amplitude of accommodation significantly affected axial growth (F = 7.395, P = 0.009) . The axial growth of subjects with below average amplitude of accommodation and those with above average amplitude of accommodation was (0.23 ± 0.25) and (0.44 ± 0.30) mm, indicating a statistically difference(t = -2.719, P = 0.009). AL change in subjects with below average amplitude of accommodation was 55.81% that of the subjects with above average amplitude of accommodation. Baseline amplitude of accommodation was positively correlated to axial growth at 24-month visit (r = 0.502, P < 0.001). Linear regression analysis was used between baseline amplitude of accommodation and 2-year axial growth: Axial growth = 0.055· Baseline amplitude of accommodation-0.409(F = 15.806, P < 0.001). The change of amplitude of accommodation for subjects with below average amplitude of accommodation and those with above average amplitude of accommodation after 2-year was (4.04 ± 2.16) D and (0.91 ± 2.15) D, indicating statistically difference (t = 5.084, P < 0.001). CONCLUSIONS: Myopic control effect would be more beneficial to lower amplitude of accommodation children than that to higher amplitude of accommodation children in orthokeratology. The enhancement of accommodation provides some basis for slowing myopia progression with orthokeratology.

Visual impairment and spectacle coverage rate in Baoshan district, China: population-based study.

BACKGROUND: To investigate the prevalence and risk factors of visual impairment associated with refractive error and the unmet need for spectacles in a special suburban senior population in Baoshan District of Shanghai, one of several rural areas undergoing a transition from rural to urban area, where data of visual impairment are limited. METHODS: The study was a population based survey of 4545 Chinese aged (age: >60 years or older ) at Baoshan, Shanghai, in 2009. One copy of questionnaire was completed for each subject. Examinations included a standardized refraction and measurement of presenting and best corrected visual acuity (BCVA) as well as tonometry, slit lamp biomicroscopy, and fundus photography. RESULTS: The prevalence of mild (6/12 to 6/18), moderate (6/18 to 6/60) and severe visual impairment was 12.59%, 8.38% and 0.44%, respectively, and 5.26%, 3.06% and 0.09% with refractive correction. Visual impairment was associated with age, gender, education and career, but not insurance . The prevalence of correctable visual impairment was 5.81% (using 6/18 cutoff) and 13.18% (using 6/12 cutoff). Senior people and women were significantly at a higher risk of correctable visual impairment, while the well-educated on the contrary. The prevalence of undercorrected refractive error (improves by 2 or more lines with refraction) was 24.84%, and the proportion with undercorrected refractive error for mild, moderate , severe and no visual impairment was 61.54%, 67.98%, 60.00% and 14.10%, respectively. The spectacle coverage rate was 44.12%. Greater unmet need for spectacles was observed among elderly people, females, non-peasant, and subjects with less education and astigmatism only. CONCLUSIONS: High prevalence of visual impairment, visual impairment alleviated by refractive correction, and low spectacle coverage existed among the senior population in Baoshan District of Shanghai. Education for the public of the importance of regular examination and appropriate and accessible refraction service might be helpful to solve the problem.

Regional macular light sensitivity changes in myopic Chinese adults: an MP1 study.

PURPOSE: To investigate the variation of macular light sensitivity (MLS) in myopic Chinese adults by using microperimetry. METHODS: MLS was recorded with the MP1 microperimeter (Nidek Technologies, Padova, Italy) in eyes affected by various degrees of myopia. Subjects were divided into group A (18-30 years) and group B (31-60 years). Subjects in both age groups were further divided based on refractive status: (1) high myopia (spherical equivalent, SE<-6.00 D); (2) low to moderate myopia (-6.00 D