Search Results (34)

Objective: This study aims to examine the anterior chamber structure and related factors in 8-year-old children based on data from The Yamanashi Adjunct Study of the Japan Environment and Children’s Study (JECS). Methods: A total of 709 children aged 8 years (350 boys and 359 girls) who participated in the JECS Adjunct Study were included. The right eyes were primarily used for measurements. Optical Coherence Tomography (OCT) was utilized to scan the anterior chambers of the participants’ eyes. The following parameters were measured: Angle Opening Distance (AOD500, 750), Trabecular Iris Space Area (TISA500, 750), Anterior Chamber Angle (ACA500, 750), Peripheral Iris Thickness (IT500, 750), and Peripheral Corneal Thickness (PCT500, 750). The relationships between anterior chamber structure, axial length (AL), spherical equivalent (SE), logMAR (without correction), and body height were analyzed. Results: A significant negative correlation was found between SE and ACA (500: coefficient = −0.19; 750: −0.24), AOD (500: −0.19; 750: −0.24), and TISA (500: −0.17; 750: −0.23) (p < 0.001). Conversely, a significant positive correlation was observed between AL and ACA (500: 0.22; 750: 0.26), AOD (500: 0.25; 750: 0.30), and TISA (500: 0.24; 750: 0.29) (p < 0.001). Boys exhibited a longer AL (boys: girls = 23.30 ± 0.76 mm; girls = 22.79 ± 0.72 mm) and greater CT (500: boys = 812.82 ± 51.94 mm; girls = 784.48 ± 51.81 mm; 750: boys = 776.01 ± 48.64 mm; girls = 751.34 ± 49.63 mm) compared to girls (p < 0.001) despite no significant difference in body height. CT and IT showed no correlation with AL or SE, and visual acuity had minimal correlation with IT and CT. Conclusions: In our cohort of eight-year-old children, the anterior chamber angle structure correlates with ocular structures and refractive error, revealing notable differences between boys and girls. Full article

Background/Objectives: Different surgical techniques are available in cases of missing or insufficient capsular bag support. Next to the anterior chamber or iris-fixated intraocular lenses (IOL), the implantation of the Carlevale IOL provides a sutureless and scleral fixated treatment method. Methods: In a retrospective single-center study, the perioperative data of 100 patients who consecutively received a scleral fixated Carlevale IOL combined with a 25 gauge (G) pars plana vitrectomy between September 2021 and June 2024 were investigated. The intraoperative and postoperative results were analyzed in terms of complication rates and refractive outcomes. Results: IOL dislocation was the most common surgical indication (50%) for sutureless Carlevale IOL implantation, followed by postoperative aphakia in 35 patients (35%). Nearly every fourth patient (24%) had a preoperative traumatic event, and 21% had pseudoexfoliation (PEX) syndrome. The average surgery time was 60.2 (±20.1) min. Intraoperative intraocular hemorrhage occurred in seven cases, and IOL haptic breakage in two patients. Temporary intraocular pressure fluctuations represented the most common postoperative complications (28%). Severe complications such as endophthalmitis or retinal detachment were not observed in our cohort. The mean refractive prediction error was determined in 67 patients and amounted to an average of −0.7 ± 2.0 diopters. The best corrected visual acuity (BCVA) at the last postoperative follow-up showed an improvement of 0.2 ± 0.5 logMAR (n = 76) compared to the preoperative BCVA (p = 0.0002). The postoperative examination was performed in 72% of the patients, and the mean follow-up period amounted to 7.2 ± 6.4 months. Conclusions: Overall, sutureless and scleral fixated implantation of the Carlevale IOL represents a valuable therapeutic option in the treatment of aphakia and lens as well as IOL dislocation in the absence of capsular bag support with minor postoperative complications and positive refractive outcomes. Full article

Background/Objectives: To propose a combined surgery of surgically induced macular detachment (MD) and autologous internal limiting membrane (ILM) transplantation to treat refractory full thickness macular holes (FTMHs). Methods: A series of patients affected by refractory FTMHs underwent a combined surgery. The following demographic and clinical data were collected: age, gender, eye, lens status, and best corrected visual acuity (BCVA). The tomographic pre- and post-operative parameters were the following: pre-operative FTMH diameter, refractory FTMH morphology (flat/with cuff), FTMH closure, foveal profile (regular/flat/inverted), flap displacement, and outer retinal layers restoration. Results: The study included a total of 14 pseudophakic eyes (14 patients). In all of the patients, surgical FTMH closure was reached. The mean BCVA improved after surgery from 1.1 ± 0.14 to 0.48 ± 03 logMAR (p < 0.0001). Statistical analysis demonstrated that the larger the FTMH, the poorer the post-operative gain in BCVA (p −0.5). The post-operative regular foveal profile was obtained in 50% of the eyes with a mean post-operative BCVA of 0.3 logMAR. A negative correlation between the time interval from diagnosis to surgery and post-operative BCVA gain was highlighted (p −0.8). Conclusions: The proposed combined surgical technique led to encouraging anatomical and functional results. Surgically induced MD increased the elasticity of the retina, and the free flap isolated the macular hole from the vitreous chamber favoring its closure. Full article

Background: This study aimed to compare the anterior segment characteristics of patients with central serous chorioretinopathy (CSCR) to those with diabetic retinopathy (DR) and healthy controls. Additionally, it explored the possible associations between quality of life and anxiety with CSCR. Methods: A single-center, cross-sectional study involving patients aged 23–61 years diagnosed with CSCR or DR, and healthy patients. Comprehensive ophthalmic examinations included best-corrected visual acuity (BCVA, LogMAR), objective and subjective refraction, and anterior and posterior segments optical coherence tomography (OCT) imaging. Participants completed the Quality-of-Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) and the Beck Anxiety Inventory (BAI). Statistical analysis included Kruskal–Wallis, Tukey post-hoc, Chi-square, and Spearman correlation tests to compare the three groups. Results: A total of 53 patients were recruited (16 CSCR, 8 DR, 29 controls; 52.8% males), with an additional 16 CSCR patients completed only the questionnaires. CSCR and DR patients were the same age as the controls (43.8 ± 9.0, 42.7 ± 9.9, 37.06 ± 13.61 years, respectively, p = 0.19). CSCR and DR patients had similar BCVA, lower than controls (0.19 ± 0.30, 0.15 ± 0.13, 0.01 ± 0.02 LogMAR, respectively, p < 0.01). CSCR patients exhibited more hyperopic refraction compared to healthy controls (p < 0.01) and reported significantly lower life enjoyment and satisfaction than DR and healthy individuals (51.56 ± 9.17, 53.75 ± 7.81, 60.03 ± 7.32, respectively, p < 0.01). No significant correlations were found between anxiety levels and pupil size, anterior chamber depth (ACD), amplitude of accommodation (AA), and intraocular pressure (IOP) among study groups (p > 0.05). Conclusions: CSCR patients demonstrated lower life enjoyment and satisfaction, reduced BCVA, and hyperopic refraction compared to healthy patients. They also tended to have higher stress and anxiety levels. Both CSCR and DR patients shared similar anterior segment characteristics. Full article

Background: This study compared the visual and morphological outcomes between iris fixation and anterior chamber intraocular lens (ACIOL) implantation for late spontaneously dislocated intraocular lens (IOL)–capsular bag complexes in a tertiary reference center in Lithuania. Methods: A prospective observational study was conducted between 2017 and 2019 involving 80 patients (83 eyes) with late spontaneous IOL–capsular bag dislocation. Patients underwent repositioning and fixation of the dislocated IOL to the iris (IF group) or IOL exchange with an ACIOL implant (ACIOL group). Pre- and postoperative assessments included best-corrected distance visual acuity (BCDVA), intraocular pressure (IOP), corneal endothelial cell density (ECD) and macular thickness (evaluating whether cystoid macular edema (CME) had occurred). Results: Both groups showed a significant improvement in BCDVA, with a more remarkable improvement in the IF group (median: 0.1 logMAR) than in the ACIOL group (median: 0.3 logMAR), p = 0.001. Corneal astigmatism increased significantly in the ACIOL group (p < 0.001) but remained stable in the IF group. IOP management outcomes were better in the IF group as fewer eyes required additional glaucoma treatment. ECD decreased in both groups, but the decrease was significantly greater in the ACIOL group (p < 0.001). Postoperative CME occurred in 4.4% of IF eyes and 39% of ACIOL eyes (p = 0.01). Conclusions: The iris fixation of late dislocated IOL–capsular bag complexes is a safe and minimally invasive technique that offers better visual outcomes, less astigmatism and fewer complications than ACIOL exchange. Full article

The ability to predict lift is crucial for enabling flapping flights on planets with varying air densities and gravities. After determining the lift required for a flapping flight on Earth, it can be predicted under different conditions using a scaling equation as a function of air density and gravity, assuming the cycle-average lift coefficient remains constant. However, in flapping wings, passive deformation due to aerodynamic and inertial forces may alter the flapping-wing kinematics, complicating predictions. In this study, we investigated changes in the lift coefficient of flapping wings under various air density and gravity conditions simulated using a low-pressure chamber and tilting stand, respectively. The current study found that the cycle-averaged lift coefficients remained nearly constant, varying by less than 7% across the air density and gravity conditions. The difference between the measured and predicted hovering frequencies increased under a lower air density due to the higher vibration-induced friction. The power consumption analysis demonstrated higher energy demands in thinner atmospheres and predicted a required power of 5.14 W for a hovering flight on Mars, which is a 66% increase compared to that on Earth. Future experiments will test Martian air density and gravity conditions to enable flapping flights on Mars. Full article

Background: The aim of this retrospective study was to compare the surgical and refractive outcomes using the Carlevale IOL (FIL SSF; SOLEKO) with those of the retropupillary-fixated Artisan IOL (Aphakia Model 205; OPHTEC), implanted through a 6 mm sclerocorneal tunnel incision in both groups. Methods: This study included 51 consecutive eyes (25 Carlevale and 26 Artisan IOLs). Due to complex preoperative conditions (e.g., dislocated polymethylmethacrylat IOL, luxated Cataracta rubra), all patients underwent lens explantation using a standardized 6 mm sclerocorneal tunnel incision and a 23 G or 25 G pars plana vitrectomy. Visual acuity (VA), spherical equivalent, refractive prediction error (PE), incision-suture time, and complication rates were recorded preoperatively and during the follow-up period. Results: The average follow-up period was 40.9 ± 5.7 days. VA improved by 0.28 ± 0.39 logMAR (p < 0.0001) in the Carlevale group and by 0.36 ± 0.47 logMAR (p < 0.0001) in the Artisan group. The improvement was comparable between both groups (p = 0.921). The deviation of the PE was −0.67 ± 0.56 in the Carlevale group and 0.34 ± 0.71 in the Artisan group (p < 0.0001). The mean incision-suture time was 42.5 ± 5.8 min in the Carlevale group and 28.2 ± 6.4 min in the Artisan group. Anterior chamber and vitreous hemorrhages were the most common complications, occurring in 12% in the Carlevale group and 17.2% in the Artisan group. Conclusions: The use of the Carlevale IOL, implanted using a sclerocorneal tunnel technique, presents a valid option for treating complex lens dislocations. The scleral fixation of the Carlevale IOL minimizes risks associated with iris fixation, such as chronic inflammation and pupil distortion, making it particularly suitable for patients with damaged irises. Full article

Objectives: This study aimed to describe the outcomes of a staged procedure combining Descemet membrane endothelial keratoplasty (DMEK) and sutureless scleral fixation (SSF) of a one-piece intraocular lens (IOL) in a case series. Co-performing endothelial keratoplasty (EK) and SSF is associated with intraoperative and postoperative complications such as graft deployment difficulties, air migration, graft detachment, and IOL opacification or tilt, all of which are evaluated in this study. Methods: This is a retrospective observational case series. Clinical data were collected from eight eyes of eight patients who underwent DMEK for endothelial failure and had previously received an SSF with one-piece IOL following complete vitrectomy. During DMEK surgery, an air leak test was conducted to check for air migration into the posterior chamber. If instability was detected, pupilloplasty was performed. Intraoperative and postoperative data, including DMEK graft unfolding time, were collected. Corrected Distance Visual Acuity (CDVA), refraction, endothelial cell density (ECD), central corneal thickness (CCT), intraocular pressure (IOP), and complications were recorded over a 12-month follow-up period. Results: We performed pupilloplasty in four patients (50%). The median CDVA improved from preoperative 0.85 logMAR (range: 0.60 to 1.00) at baseline to 0.18 logMAR (range: 0.10 to 0.70, p = 0.012) at 12 months. The median refraction value changed significantly from −1.00 to −0.50 at 12 months. The median percentage reduction in ECD after 12 months was 33.4% (range 30 to 40). The median baseline CCT was 689 μm (range: 651 to 701) at baseline visit and 541.5 μm (range: 525 to 591, p = 0.008) at 12 months. The median IOP was reduced significantly during follow-up. The median graft unfolding time was 6 min (5 to 9). One patient required rebubbling for partial detachment on postoperative day one. No complications occurred within 12 months. Conclusions: The effective compartmentalization of the anterior and posterior chambers in vitrectomized eyes with an SSF one-piece IOL and pupilloplasty can facilitate critical steps of DMEK surgery in complex eyes. Additionally, the air leak test could prove useful in identifying the need for iris-lens diaphragm reconstruction. Full article

The need to refuel future missions to Mars and the Moon via in situ resource utilization (ISRU) requires the development of LOX/LCH4 engines, which are complex and expensive to develop and improve. This paper discusses how the use of digital engineering—specifically physics-based modeling (PBM)—can aid in developing, testing, and validating a LOX/LCH4 engine. The model, which focuses on propulsion performance and heat transfer through the engine walls, was created using Siemens’ STAR-CCM+ CFD tool. Key features of the model include Eulerian multiphase physics (EMP), complex chemistry (CC) using the eddy dissipation concept (EDC), and segregated solid energy (SSE) for heat transfer. A comparison between the complete GRI 3.0 and Lu’s reduced combustion mechanisms was performed, with Lu’s mechanism being chosen for its cost-effectiveness and similar output to the GRI mechanism. The model’s geometry represents 1/8th of the engine’s volume, with a symmetric rotational boundary. The performance of this engine was investigated using NASA’s chemical equilibrium analysis (CEA) and STAR-CCM+ simulations, focusing on thrust levels of 125 lbf and 500 lbf. Discrepancies between theoretical predictions and simulations ranged from 1.4% to 28.5%, largely due to differences in modeling assumptions. While NASA CEA has a zero-dimensional, steady-state approach based on idealized conditions, STAR-CCM+ accounts for real-world factors such as multiphase flow, turbulence, and heat loss. For the 125 lbf case, a 9.2% deviation in combustion chamber temperature and a 15.0% difference in thrust were noted, with simulations yielding 113.48 lbf compared to the CEA’s 133.52 lbf. In the 500 lbf case, thrust reached 488 lbf, showing a 2.4% deviation from the design target and an 8.6% increase over CEA predictions. Temperature and pressure deviations were also observed, with the highest engine wall temperature at the nozzle throat. Monte Carlo simulations revealed that substituting LNG for LCH4 affects combustion dynamics. The findings emphasize the need for advanced modeling approaches to enhance the prediction accuracy of rocket engine performance, aiding in the development of digital twins for the CROME. Full article

A Planetary Atmospheric Chamber (PAC) was used to create simulations of interplanetary conditions to test the spore survival of three Bacillus spp. exposed to interacting conditions of vacuum (VAC), simulated solar heating (HEAT), and simulated solar ultraviolet irradiation (UV). Synergism was observed among the experimental factors for all three Bacillus spp. tested that suggested the increased lethality of HEAT and UV when concomitantly exposed to VAC. The most aggressive biocidal effects were observed for assays with VAC + HEAT + UV conditions run simultaneously over short time-steps. The results were used to predict the accumulation of extremely rapid Sterility Assurance Levels (SALs; def., −12 logs of bioburden reduction) measured in a few minutes to a few hours for external surfaces of interplanetary spacecraft. Furthermore, the results were extrapolated to predict that approx. 1 × 10⁴ SAL exposures might be accumulated for external surfaces on the Europa Clipper spacecraft during a 3.5-year transit time between Venus (0.7 AU) and Mars (1.5 AU) during a series of Venus–Earth–Earth gravity assists (VEEGA trajectory) to Jovian space. The results are applicable to external spacecraft surfaces exposed to direct solar heating and UV irradiation during transits though the inner solar system. Full article

Background: The aim of this study was to evaluate the short-term efficacy and safety of the Paul Glaucoma Implant (PGI) in pediatric eyes diagnosed with glaucoma following congenital cataract surgery (GFCS). Methods: A retrospective, single-center, descriptive study was conducted on consecutive children diagnosed with GFCS who underwent PGI implantation between July 2022 and November 2023 at the University Medical Center Mainz. The primary outcome measure was the reduction in IOP at the last follow-up visit. Results: Ten eyes of nine children were included in the study. The mean follow-up time was 7.70 ± 4.22 months (4.68–10.72 months). At the end of the study follow-up, the mean (95% CI) reduction in IOP was −14.8 ± 8.73 mmHg (−8.56 to −21.04 mmHg, p < 0.001). At the last follow-up, 30.0% (3/10) of patients achieved an IOP (intraocular pressure) of ≥6 and ≤21 mmHg with a reduction in IOP of ≥25% without treatment, while 90.0% (9/10) achieved this target IOP regardless of glaucoma medication treatment. The mean number of antiglaucoma medications was significantly reduced from 3.50 (IQR = 1) to 2.0 (IQR = 2, p = 0.01), and the visual acuity logMAR improved from 1.26 ± 0.62 to 1.03 ± 0.48 (p = 0.04). Only one eye experienced numerical hypotony (4 mmHg) without choroidal detachment or anterior chamber shallowing within the first 24 h. No other adverse events were observed during the follow-up period. Conclusions: PGI implantation significantly lowered IOP and the number of antiglaucoma eye drops with a favorable safety profile in children diagnosed with GFCS, thereby achieving a high rate of qualified surgical success in the short term. Full article

Background: In this study, we aimed to report the short-term (6 months) effects on visual functionality and safety of femto-laser assisted smaller-incision new-generation implantable miniature telescope (SING-IMT™) implanting, particularly related to postsurgical intraocular pressure increase, in patients suffering from end-stage age-related macular degeneration (AMD) and cataract. This device, designed for monocular use, aims to minimise the impact of the central scotoma by projecting the images onto a larger area of the photoreceptors surrounding the macula. Methods: In this prospective multicentric observational case series study, 6 eyes of 6 patients who underwent SING-IMT™ implantations were enrolled. At baseline and 6 months follow-up, best corrected distance visual acuity (BCDV) and best corrected near visual acuity (BCNVA), intraocular pressure (IOP), anterior chamber depth, endothelial cells count were assessed. In addition, IOP was also measured at 7, 15, 30, 45 days, and at 3 months follow-up. Finally, the incidence of complications was evaluated. Results: At final follow-up, in the study eyes, mean BCDVA improved by +10.0 letters (6.25; 13.8) letters and mean BCNVA improved by −0.30 logMAR (−0.55; −0.20). At postoperative month 6, we reported a mean IOP decrease of 4.50 mmHg (−5.75; −0.25). Interestingly, 83.3% of patients had an increased IOP value in at least one of the first two postoperative follow-ups (7 days and 15 days). In patients in whom intraoperative mechanical iridotomy was not performed, it was necessary to perform a postoperative YAG laser iridotomy to improve IOP management. Compared to the baseline, ECD loss at 6 months follow-up was 12.6%. Conclusions: The SING IMT™ device was found to be effective in the distance and near vision improvement, without serious postoperative complications. We recommend intraoperative mechanical iridectomy in order to easily manage post-operative IOP and to avoid sudden IOP rise with its possible consequences. These good results can be a hope to partially improve the quality of life of patients suffering from severe end stage macular atrophy. Full article

Background: Early vitrectomy for postsurgical endophthalmitis may improve visual acuity outcomes. Silicone oil as a tamponade has some potential benefits in the management of endophthalmitis. This study aims to evaluate the use of a silicone oil tamponade in the surgical management of endophthalmitis. Material and Methods: All patients with a pars plana vitrectomy with silicone oil tamponade for postsurgical endophthalmitis at the Department of Ophthalmology, University of Bonn, Germany, between 2017 and 2021 were retrospectively reviewed. We included all preoperative data, including BCVA at diagnosis, clinical findings, and symptoms. For every follow-up visit, we looked at BCVA and complications. Results: In total, 82 patients were included in this study. The mean follow-up was 13.1 months (range 1–58 months). An intravitreal injection was the cause in 42 patients (51.2%) and cataract surgery in 29 patients (35.4%). The mean interval between the causing event and the date of onset was 8.8 days (range, 1–59 days). The most prevalent pathogen was Staphylococcus epidermidis in 16 patients (19.5%). In 47 patients (57.3%), no pathogen was found. The initial best-corrected visual acuity was 2.1 logMAR and improved significantly to 1.0 logMAR after six months (p < 0.001) and 1.1 logMAR after 1 year (p < 0.001). In a multivariate analysis, a low BCVA at diagnosis (p = 0.041) was a significant predictor for poor visual acuity outcomes. A total of 17 patients (20.1%) developed postoperative complications. Five patients (6.1%) needed an anterior chamber washout with repeated injections of antibiotics. Two patients (2.4%) had persistent fibrin and were treated with YAG-laser treatment. Three patients (6.7%) developed a retinal detachment. Two patients (2.4%) had persistent corneal decompensation with endothelial cell loss and received perforating keratoplasty. We performed a matched-pair analysis (n = 30, each group n = 15) to compare a silicone oil tamponade with BSS at the end of surgery. The visual acuity outcome showed no significant differences (BCVA after one year: 1.17 logMAR in eyes with silicone oil and 0.90 logMAR in eyes with BSS; p = 0.684). Conclusions: In our study, a vitrectomy with silicone oil tamponade in the surgical management of postoperative endophthalmitis led to a significant improvement in visual acuity and had a low complication rate. Low BCVA at diagnosis was significantly associated with poor visual acuity outcomes. A comparison of silicone oil and BSS at the end of surgery showed similar results. Full article

Compared to detection methods employed by Mars rovers and orbiters, the employment of Mars UAVs presents clear advantages. However, the unique atmospheric conditions on Mars pose significant challenges to the design and operation of such UAVs. One of the primary difficulties lies in the impact of the planet’s low air density on the aerodynamic performance of the UAV’s rotor system. In order to determine the aerodynamic characteristics of the rotor system in the Martian atmospheric environment, a rotor system suitable for the Martian environment was designed under the premise of fully considering the special atmospheric environment of Mars, and the aerodynamic characteristics of the rotor system in the compressible and ultra-low Reynolds number environment were numerically simulated by means of a numerical calculation method. Additionally, a bench experiment was conducted in a vacuum chamber simulating the Martian atmospheric environment, and the aerodynamic characteristics of the UAV rotor system in the Martian environment were analyzed by combining theory and experiments. The feasibility of the rotor system applied to the Martian atmospheric environment was verified, and the first generation of Mars unmanned helicopters was developed and validated via hovering experiments, which thereby yielded crucial data support for the design of subsequent Mars UAV models. Full article

Aim: To determine the clinical risk factors that may increase the occurrence of intraocular lens (IOL) calcification in patients who had undergone pars plana vitrectomy (PPV). Methods: The medical records of 14 patients who underwent IOL explantation due to clinically significant IOL opacification after PPV were reviewed. The date of primary cataract surgery, technique and implanted IOL characteristics; the time, cause and technique of PPV; tamponade used; additional surgeries; the time of IOL calcification and explantation; and IOL explantation technique were investigated. Results: PPV had been performed as a combined procedure with cataract surgery in eight eyes and solely in six pseudophakic eyes. The IOL material was hydrophilic in six eyes, hydrophilic with a hydrophobic surface in seven eyes and undetermined in one eye. The endotamponades used during primary PPV were C2F6 in eight eyes, C3F8 in one eye, air in two eyes and silicone oil in three eyes. Two of three eyes underwent subsequent silicone oil removal and gas tamponade exchange. Gas in the anterior chamber was detected in six eyes after PPV or silicone oil removal. The mean interval between PPV and IOL opacification was 20.5 ± 18.6 months. The mean BCVA in logMAR was 0.43 ± 0.42 after PPV, which significantly decreased to 0.67 ± 0.68 before IOL explantation for IOL opacification (p = 0.007) and increased to 0.48 ± 0.59 after the IOL exchange (p = 0.015). Conclusions: PPV with endotamponades in pseudophakic eyes, particularly gas, seems to increase the risk for secondary IOL calcification, especially in hydrophilic IOLs. IOL exchange seems to solve this problem when clinically significant vision loss occurs. Full article