Efficacy of scleral buckling for the treatment of rhegmatogenous retinal detachment using a novel foldable capsular buckle

●AIM:To evaluate the effectiveness and safety of scleral buckling for the treatment of rhegmatogenous retinal detachment(RRD)using a novel foldable capsular buckle(FCB).●METHODS:This was a series of case observation studies.Eighteen patients(18 eyes)who visited our ophthalmology department between August 2020 and August 2022 and were treated for RRD with scleral buckling using FCB were included.The procedure was similar to conventional scleral buckling,while a balloon-like FCB was placed onto the retinal break with balanced salt solution filling for a broad,external indentation instead of the silicone buckle.The retinal reattachment rate,best corrected visual acuity(BCVA),intraocular pressure(IOP),refractive dioptre and astigmatism degree,and complications were evaluated and recorded.●RESULTS:There were 7 males and 11 females aged 19-58y.The average time course of RRD was 12d,ranging from 7-20d.The retinal break was located in the superior quadrants in 8 eyes and in the inferior quadrants in 10 eyes,with macula-off detachments in 12 eyes.The patients were followed-up for at least 6mo.The final retinal reattachment rate was 100%.The BCVA was significantly improved compared with the baseline(P<0.05).There was no significant change in refractive dioptre or astigmatism degree at each follow-up(all P>0.05).Three patients had transiently high IOPs within one week after surgery.Mild diplopia occurred in 5 patients after surgery and then disappeared after the balloon fluid was removed.●CONCLUSION:The success rate of FCB scleral buckling for RRD is satisfactory.This procedure can be expected to be applied in new,uncomplicated cases of RRD.

Clinical Efficacy and Safety of Foldable Capsular Vitreous Body Implant Surgery in 22 Cases of Silicone Oil-dependent Eyes

Objective This study aimed to evaluate the clinical efficacy and safety of foldable capsular vitreous body(FCVB)implant surgery in silicone oil-dependent eyes.Methods A total of 22 participants with silicone oil-dependent eyes who received treatment with FCVB implant surgery between January 2019 and June 2020 were included in this retrospective study.The intraocular pressure(IOP),best-corrected visual acuity(BCVA),demographic data,and any recorded complications were evaluated.Results The postoperative IOP(12.73±4.20 mmHg)was significantly improved(P=0.03)compared to the preoperative IOP(10.23±3.69 mmHg)(the main endpoint).There was no significant difference(P=0.33)in the final BCVA preoperation and 3rd month postoperation(the secondary endpoint).The most common postoperative complication was hyphema.Other common postoperative complications included corneal opacity,a shallow anterior chamber,and a low IOP.Conclusion FCVB implant surgery is a safe and effective method for treating silicone oil-dependent eyes;however,attention should be paid to the prevention and timely treatment of complications.

Comparison of iris-fixated foldable lens and scleralfixated foldable lens implantation in eyes with insufficient capsular support

AIM： To compare the outcomes of vision using two different intraocular lens（IOL） replacement techniques,iris-fixated foldable intraocular lens（IF-IOL） and scleralfixated foldable intraocular lens（SF-IOL） in patients with insufficient capsular support.METHODS： Total 63 eyes（62 patients） with insufficient posterior capsule support underwent replacement of IF-IOL or SF-IOL between January 2008 and August 2011.Outcome measures included changes in visual acuity, slit lamp examination, refractive indices and corneal curvatures. RESULTS： The mean improvement of uncorrected visual acuity（UCVA） was greater in IF-IOL group compared to the SF-IOL group（0.43 D±0.19 D vs 0.35 D±0.18 D, P 〈0.05）. Moreover, 12（38.71%） eyes in IF-IOL group and 4（12.50%） in SF-IOL group had a higher postoperative UCVA than preoperative best corrected visual acuity（BCVA） while 9（29.03%） eyes in IF-IOLgroup and 18（56.25%） in SF-IOL group had a lower postoperative UCVA than preoperative BCVA. The myopic mean manifest sphere and mean cylinder magnitude were lower in the IF-IOL group than that in the SF-IOL group（-0.47 D±0.58 D vs 0.50 D±0.43 D, P 〈0.01; 0.84 D ±0.53 D vs 1.23 D ±0.70 D, P 〈0.05）. No difference of corneal astigmatism and surgically induced astigmatism was found between the two groups. In addition, fewer complications were observed in IF-IOL eyes. CONCLUSION： IF-IOL implantation can give a significant improvement in vision with fewer complications than SF-IOL in patients with insufficient capsular support.

Visual performance after implantation of two types of phakic foldable intraocular lenses for correction of high myopia

AIM: To compare Visian lens(model V4 c) and Artiflex lens regarding quality(contrast sensitivity) and quantity(efficacy, predictability, safety and stability) of vision in correcting high myopia with recording and analysis of complications. METHODS: The comparative prospective study included 39 eyes of 23 patients with high myopia, 19 eyes had Visian lens implantation(model V4 c) and 20 eyes had Artiflex lens implantation. The inclusion criteria were high myopia(higher than 6.0 D) and stable refraction(<0.5 D change over one year). Outcomes included assessment of safety and efficacy indices, predictability, stability, contrast sensitivity and analysis of complications at postoperative 1 d, 1 wk and 1, 3, 6 and 12 mo. Selection of the type of phakic intraocular lens for patients was based on surgeons' preferences, which was no specific selection criteria. RESULTS: After 12 mo of follow up, difference in uncorrected and corrected distant visual acuity(CDVA) between both groups was statistically insignificant(UDVA for VisianV4 c and Artiflex lens were 0.33±0.2 logMAR and 0.37±0.2 logMAR respectively, P=0.59, CDVA for VisianV4 c and Artiflex lens were 0.155±0.1 logMAR and 0.147± 0.1 logMAR respectively, P=0.87). The efficacy index was 1.25 for VisianV4 c lens and 0.8 for Artiflex lens, 78.9% of eyes were within one diopter spherical equivalent in Visian V4 c lens group compared to 70% in the Artiflex lens group. No eye lost lines of CVDA proving a good safety index for both lenses(safety index was 1.67 for VisianV4 c lens and 1.34 for Artiflex lens). Difference in contrast sensitivity between both groups was statistically insignificant(P=0.15, 0.88, 0.27, 0.32 and 0.82 at five spatial frequencies). CONCLUSION: Both Visian ICL V4 c and Artiflex lensesare safe and effective with stable and predictable refraction and they have comparable contrast sensitivity outcomes with no vision threatening complications.

Evaluation of the long-term effect of foldable capsular vitreous bodies in severe ocular rupture

AIM:To evaluate the long-term effect of foldable capsular vitreous body(FCVB)in the treatment of severe ocular rupture to provide a practical basis for clinical selection.METHODS:A total of 26 patients(26 eyes),23 men and 3 women,with severe ocular rupture who underwent FCVB implantation between March 2018 and September 2018 were retrospectively analysed.All open ocular wounds located in zone III,with preoperative visual acuity grade IV and above(Snellen less than 4/200).The best corrected visual acuity(BCVA),intraocular pressure(IOP),cornea,anterior chamber,iris,lens,choroid,and retina were evaluated before and after the surgery.The subjective feeling and the location of FCVB were also assessed.RESULTS:The average age of the 26 patients was 36y(20-60y).Postoperative follow-up was from 10 to 14mo.At the end of follow up,BCVA was light perception(LP)in 10 cases,no light perception(NLP)in 13 cases,hand motions(HM)in 3 cases.IOP was 11±5 mm Hg.Corneal degeneration was in 3 cases and corneal endothelial dystrophy was in 7 cases.Shallow anterior chamber was in 8 cases and hyphema was in 8 cases.Organized membrane in the pupil was in 14 cases.Epiphora occurred in 3 cases.FCVB drainage tube exposed in 3 cases.All FCVBs were in their normal location and no rejection occurred.CONCLUSION:FCVB implantation is a long-term effective treatment and may provide a practical selection for severe ocular rupture.

Evaluation of suturless scleral fixation with posterior chamber foldable intraocular lens implantation

AIM: To assess the sutureless scleral fixation technique for posterior chamber foldable intraocular lens(PCIOL) implantation in aphakic eyes with insufficient or no capsular support. METHODS: A technique for sutureless intrascleral fixation of the haptics of a standard 3-piece PCIOL was used which ensures sutureless fixation by permanent incarceration of the haptics in a scleral tunnel parallel to the limbus. All patients were evaluated for preoperative status [visual acuity, refractive error, K readings, intraocular pressure(IOP) measurement, slit lamp examination, fundus examination and optical biometry], postoperative status and complications. Ultrasound biomicroscopy(UBM) was done for 10 cases to evaluate optic tilt. RESULTS: The study evaluated 42 eyes of 42 patients. The follow-up period was 6 mo. Improvement of best corrected visual acuity(BCVA) one line occurred in 10 cases(23.8%) and loss of one line in 3 cases(7.1%). Intraoperative complications included: haptic kink in 4 cases(9.5%), haptic breakage in 1 case(2.4%), haptic dislocation in 1 case(2.4%), haptic slippage in 3 cases(7.1%), IOL dislocation in 1 case(2.4%) and sclerotomy related bleeding in 1 case(2.4%). Postoperative complications included: transient mild vitreous hemorrhage in 3 cases(7.1%), choroidal detachment in 1 case(2.4%), cystoid macular edema(CME) in 1 case(2.4%), optic capture in 1 case(2.4%), subconjunctival haptic in 2 cases(4.8%), ocular hypotony in 4 cases(9.5%) and ocular hypertension in 1 case(2.4%). There were no cases of retinal detachment or endophthalmitis. UBM showed optic tilt in 3 cases(30%). CONCLUSION: Fixation of three-piece foldable IOL haptics in scleral tunnel parallel to the limbus-providedaxial stability and proper centration of the IOL with minimal or no tilt in most cases and a low complication rate during the follow up period which lasted 6 mo.

Determining Optimum Design Parameters of Foldable Product Using Response Surface Methodology and Genetic Algorithm

It is desired to optimize design parameters in any product development for achieving the appropriate efficiency level in any manufacturing industry. To select the best materials used, reduce cost, and increase a product’s sustainability, an analysis of all design parameters must be conducted. Suitable design parameters and their optimum ranges provide the feasibility in developing a specific product. Response Surface Methodology (RSM) provides the opportunity of checking the parameters after considering optimization strategies, which results in improving the production process. In this study, the research aims to construct a 3D model and a mathematical equation on a foldable product to optimize the design parameters. A 2-level 3 factors small Central Composite Design (CCD) method is used for planning experimental trials, and the primary objective is to determine the optimal value for three design parameters, which are fold angle, length of the cycle, and height between seat and paddle in terms of the response which is “time required to fold the product”. This paper directs attention towards response optimization to achieve minimum “time required to fold the product” using the desirability criteria of Response Surface Methodology (RSM) and the optimization approach of the Genetic Algorithm (GA). The optimum value of “time required to fold the product” is found to be 2.415 seconds with a combination of design parameters such as “fold angle” of 180°, “length of the cycle” of 74.112 cm, and “height between seat and paddle” of 0.613 m using Response Surface Methodology (RSM). The Genetic Algorithm (GA) predicts the “time required to fold the product” is 2.39 seconds and design parameters of “fold angle” of 179.559°, “length of the cycle” of 74.1 cm, and “height between seat and paddle” of 0.59 m. This similar sort of analysis can be implemented in different manufacturing industries for developing a specific product.

Hollow Co_(9)S_(8) cores encapsulated in hierarchical MXene@Bi_(2)O_(3) multiple shells for constructing binder-free electrodes of foldable supercapacitors

Rational structure design and regulation are of paramount importance for obtaining electrode materials with desirable electrochemical performance.Here,a novel binder-free electrode with the hollow Co_(9)S_(8) core@multi-shell structure(CS-x@MXene@Bi_(2)O_(3))derived from metal-organic frameworks(MOFs)precursor is well designed by the electrospinning,sulfuration,carbonization,and hydrothermal processes.In this architecture,the concentration of Co_(9)S_(8)(CS-x)is optimized for an ideal flexible substrate,which alleviates the dimensional variation for long cycle life.The unique cores and the MXene flakes engineered by Bi_(2)O_(3) multiple shells can be responsible for the superior characteristics,including a fast electronic pathway,large specific surface area,enhanced electrical conductivity,and improved electrochemical performance.As expected,the obtained CS-2@MXene@Bi_(2)O_(3) binder-free electrode exhibits a high discharge capacitance of 646.1 F g^(–1)(1 A g^(–1)).Two binder-free electrodes can be assembled into a solid-state supercapacitor with desirable energy and power density,and long-term cyclic stability is demonstrated through 5000 cycles.Given these advantages,the CS-2@MXene@Bi_(2)O_(3) is selected as the electrode in a foldable supercapacitor.More importantly,the specific capacitance is reserved after various deformations.Therefore,it is expected that binder-free electrode materials with the unique core@shell structure design could be applied in wearable and portable energy conversion devices.

Design and Demonstration of Insect Mimicking Foldable Artificial Wing Using Four-Bar Linkage Systems

In this work, we develop an artificial foldable wing that mimics the hind wing of a beetle （Allomyrina dichotoma）. In real flight, the beetle unfolds forewings and hind wings, and maintains the unfolded configuration unless it is exhausted. The artificial wing has to be able to maintain a fully unfolded configuration while flapping at a desirable flapping frequency. The artificial foldable hind wing developed in this work is based on two four-bar linkages which adapt the behaviors of the beetle＇s hind wing. The four-bar-linkages are designed to mimic rotational motion of the wing base and the vein folding/unfolding motion of the beetle＇s hind wing. The behavior of the artificial wings, which are installed in a flapping-wing system, is observed using a high-speed camera. The observation shows that the wing could maintain a fully unfolded configuration during flapping motion. A series of thrust measurements are also conducted to estimate the force generated by the flapping-wing system with foldable artificial wings. Although the artificial foldable wings give added burden to the flapping-wing system because of its weight, the thrust measurement results show that the flapping-wing system could still generate reasonable thrust.

Foldable Units and Wing Expansion of the Oakleaf Butterfly During Eclosion

Eclosion is a rapid process of morphological changes in insects,especially for the wings of butterflies.The orange oakleaf butterfly(Kallima inachus)transits from pupae to adults with a 9.3 fold instant increase in the surface area of their wings.To explore the mechanism for the rapid morphological changes in butterfly wings,we analyzed changes in microstructures in the wings of K.inachus.We found that there were lots of micron-sized foldable units in the wings at the pupal stage.The foldable units could provide as much as 31.35 times of increase in wing surface area.During eclosion,foldable units were flattened sequentially and resulted in a rapid increase in wing surface areas.The unfolding process was regulated by the structures and layouts of wing veins.Based on our observation,foldable units play important roles in both deformation and stretching of wings.The foldable units of microstructures may provide mimics for simulating entities of large-deformational bionic structures with practical application.

Vitreous substitutes: challenges and directions

The natural vitreous body has a fine structure and complex functions. The imitation of the natural vitreous body by vitreous substitutes is a challenging work for both researchers and ophthalmologists. Gases, silicone oil, heavy silicone oil and hydrogels, particularly the former two vitreous substitutes are clinically widely used with certain complications. Those, however, are not real artificial vitreous due to lack of structure and function like the natural vitreous body. This article reviews the situations, challenges, and future directions in the development of vitreous substitutes, particularly the experimental and clinical use of a new artificial foldable capsular vitreous body.

AcrySof phakic angle-supported intraocular lens for the correction of high to extremely high myopia:one-year follow-up results

AIM: To assess the safety, efficacy and predictability of the AcrySof phakic angle-supported intraocular lens (IOL) (Alcon Inc., U.S.A.) for correction of high-to-extremely high myopia in adults. METHODS: In this prospective study performed in Tianjin Medical University Eye Center & College of Optometry, Tianjin, China, 25 eyes of 13 patients were implanted with AcrySof phakic angle-supported IOLs and followed for 1 year postoperatively. Preoperative manifest refractive sphere was (-12.08 +/- 2.44) diopters (D) and cylinder was (-1.35 +/- 0.62)D. Visual acuity, predictability and stability of manifest refraction spherical equivalent (MRSE), adverse events, and endothelial cell density were analyzed during 1-year of follow-up. RESULTS: After 1 year of follow-up, no eyes lost 1 line (best spectacle-corrected visual acuity)BSCVA; an uncorrected visual acuity (UCVA) of 20/20 or better was achieved in 60% of eyes; 100% had an UCVA of 20/40 or better; a BSCVA of 20/30 or better was achieved by 100% of eyes; 84% had a BSCVA of 20/20 or better. The overall mean percentage change in endothelial cell density 1 year after surgery was (-0.27 +/- 3.60)%. Two eyes (8%) had increased intraocular pressure (IOP) on the day of surgery. No pupil ovalization, pupillary block, or retinal detachment events were observed. CONCLUSION: After 1 year of follow-up, the implantation of AcrySof phakic angle-supported IOL is proved to be safe, effective and predictable with minimal complications in patients with high-to-extremely high myopia. Due to the limitation of visiting time, long-term of clinical investigation is necessary to verify the safety and efficacy of this IOL.

Corneal injection track: an unusual complication of intraocular lens implantation and review

Phacoemulsification is the main gold standard for cataract operation in the developed world together with foldable intraocular lens(IOL) implantation by injection,allowing for stable wound construction and less postoperative astigmatism. It is a safe procedure with high success rate with the advancement in machines,improvement of IOL injection systems and further maturation of surgeons’ techniques. Despite the large number of operations performed every day, foldable IOL injection leading to an intra-stromal corneal track is a very rare complication. We report a case of this unusual finding in a 70-year-old gentleman who has undergone cataract operation in November 2011 in our hospital and will review on the complications related to foldable IOL injection.

Behaviors of Bellows-Like Origami Patterned Tubes with Trapezoidal Patterns

In this paper, we show one of the possibility utilizing typical origami structures for civil engineering fields such as the bridge bearing support. We numerically investigate axial spring constants and buckling behaviors of bellows-like origami tube structures. The bellows-like origami tube structures, which can be folded because of elastic deformations, work as a kind of spring. If the initial heights of the bellows-like origami tubes are less than 90% of the height of the prismatic tubes without bellows-like folded lines, the spring constants of the bellows-like tubes are very low compared with those of the prismatic tubes. The buckling loads and patterns of the bellows-like tubes vary depending on the initial heights of the tubes.

A Survey on Working under Trees with an Agricultural Narrow Tractor in Italy

To protect the driver in case of a tractor overturn,narrow-track tractors,mainly used for working under trees or in vineyards,can be equipped with a foldable roll-over protective structure(FROPS)generally consisting of a two-pillar front-mounted foldable rollbar.FROPSs have been mainly developed to offer greater mobility when working in low overhead clearance zones(CZs)and more storage options.However,many fatalities and serious injuries in Italy are due to overturn of narrow tractors with FROPS not in safety configuration.The reason lies on that lowering and raising a conventional FROPS is a time-consuming and strenuous process.After operators fold down FROPS to pass a low overhead CZ,some prefer to leave it in the folded or inoperative position,increasing the risk of a roll-over fatality.Italian Workers Compensation Authority(Inail)collects injury reports of workers covered by compulsory accident insurance.However,for agricultural sector Inail set up in 2008 a national observatory to add data and information on fatalities in agriculture covering workers,even those not Inail insured.From these data it appears that about 10 fatalities per year occur in Italy involving folded ROPS.The aim of the analysis in this article is to make a survey on the FROPS issue considering both what is required by Mother Regulation(Regulation(EU)167/2013)for new tractors and the achievable technical solutions to be applied on old tractors for reducing the misuse of FROPS.

An approach for formation design and flight performance prediction based on aerodynamic formation unit:Energy-saving considerations

The performance improvement of swarm drones through aerodynamic shape optimization may be challenging due to folded size constraints imposed by the specific launch approach.However,fixed-wing aircraft swarms can benefit from formation flight in terms of energy consumption.This study introduces the concept of the"aerodynamic formation unit",which consists of two or three aircraft that form an inseparable unit of the formation.Considering the Unmanned Aerial Vehicle(UAV)distribution and wingtip vortex interference in the formation,two typical aerodynamic formation units are optimized by the variable-fidelity aerodynamic optimization method based on space mapping.The aerodynamic characteristics of the formation UAVs that affect flight performance,such as lift-to-drag ratio(L/D ratio)and static stability are analyzed by Computational Fluid Dynamics(CFD)simulations.The L/D ratio(cruising condition)of the following aircraft can be increased by 22.8%and 57.5%in the optimal units that involve two and three aircraft respectively.Moreover,this study conducts several CFD simulations for multi-aircraft formations formed by the units,which show that the average L/D ratio of the formation can be improved by more than 19%.These results verify the feasibility and effectiveness of the"aerodynamic formation unit"concept and the optimization framework for formation parameters.

Progress in organic semiconducting materials with high thermal stability for organic light-emitting devices

Organic light-emitting devices(OLEDs)have been extensively studied over the past three decades and are still attracting attention owing to their potential use in flexible and foldable displays.To achieve highly durable OLED displays for flexible devices,constitutive OLED materials need to be stable in various environments,including those with thermally and mechanically severe conditions.To this end,the present review aims to investigate the progress of OLED material research over the past two decades with respect to thermal stability.The literature survey is first conducted using the keyword“OLEDs”and then narrowed down to“high thermal stability materials for OLEDs.”The number of search results indicates that creating OLED materials with high thermal stability is a widely studied topic in the field of OLED research and has undergone an average growth rate of approximately 15%per year over the past two decades.In this review,the OLED materials used as core layers(ie,the hole injection and transport layers,emission layers,and electron injection and transport layers)are thoroughly analyzed,and the best representative materials are discussed in detail by summarizing their major thermal and electronic characteristics.Finally,several previous reports on flexible and foldable OLED displays are analyzed to determine the importance of the stability of their constitutive materials.

Mechanical behavior of a shelter system based on cable-strut structures

A shelter system based on cable-strut structures,consisting of compressive struts and high-tensile elements,is described in this paper.The deployment of the shelter is achieved by tightening inclined cables.Lower cables are used to terminate the deployment.The state of self-stress of the cable-strut structures in the fully deployed configuration is given,and the minimum strut length and the maximum load design of the shelter are discussed.The mechanical behavior of the system was studied under symmetrical and asymmetrical load cases.The results show that the shelter in the deployed configuration satisfies the ultimate limit and the serviceability limit state conditions.Finally,the stability of the cable-strut system is investigated,considering the effect of imperfections on the buckling of the shelter.We conclude that the influence of imperfections based on the consistent imperfection mode method is not significant.