Changes In Thickness Research Articles

Anti-VEGF Monotherapy vs Anti-VEGF and Steroid Combination Therapy for Diabetic Macular Edema: A Meta-analysis.

Introduction: To compare the safety and efficacy of antivascular endothelial growth factor (anti-VEGF) monotherapy vs anti-VEGF and steroid combination therapy in treatment-naïve and treatment-resistant patients with diabetic macular edema (DME). Methods: A systematic literature search was conducted from January 2005 to December 2022. Sixteen randomized control trials (RCTs) published in English that reported the efficacy or safety of monotherapy and combination therapy in patients with DME were included. Results: The 16 RCTs included 1166 eyes. Monotherapy was associated with a significantly better best-corrected visual acuity (BCVA) at the final follow-up (weighted mean difference [WMD], -0.04 logMAR; 95% CI, -0.07 to -0.02; P = .002; I 2 = 0%). No significant differences were observed in the change in BCVA between groups at the final observation. Monotherapy was associated with a significantly smaller change in retinal thickness at the final follow-up (WMD, 37.63 μm; 95% CI, 11.67-63.60; P = .005; I 2 = 78%) and with a significantly lower risk for intraocular pressure-related adverse events (AEs) (risk ratio, 0.27; 95% CI, 0.15-0.46; P ≤ .001; I 2 = 0%). The risk for cataract-related AEs was not significantly different between groups (P = .06). The results in treatment-naïve patients were similar. In treatment-resistant patients, the change in retinal thickness at the final follow-up was similar between groups (P = .14) but the risk for cataract-related AEs was significantly lower in the monotherapy group in 2 RCTs (risk ratio, 0.09; 95% CI, 0.01-0.66; P = .02; I 2 = 0%). Conclusions: The changes in BCVA were similar despite combination therapy being associated with greater changes in retinal thickness. However, increased complications were seen with combination therapy. Most results in treatment-naïve patients and treatment-resistant patients were similar.

The association between change in temporal muscle mass and treatment of acromegaly

PurposeWe aimed to evaluate the relationship between temporal muscle thickness and GH/IGF-1 elevation and the effect of acromegaly treatment on temporal muscle thickness. MethodsPatients with acromegaly and healthy controls were included in the study. While laboratory parameters, clinical findings and temporal muscle thickness of acromegaly patients at the time of diagnosis and one year after treatment were evaluated, laboratory parameters and temporal muscle thickness of healthy controls were evaluated only during the period when they were included in the study. Temporal muscle thickness was measured using pituitary MRI. Temporal muscle thickness of patients with acromegaly was compared with healthy controls. We also evaluated how temporal muscle thickness changes with treatment in patients with acromegaly and the association between laboratory parameters and temporal muscle thickness. ResultsIn patients with acromegaly, measurements of left, right, and mean temporal muscle thickness at the time of diagnosis were found to be significantly higher than those of healthy controls' measurements at the time of their inclusion in the study (p = 0.007, p = 0.014 and p = 0.018, respectively). However, no significant difference was found when comparing the temporal muscle thickness of the 1st year of acromegaly treatment with the temporal muscle thickness of healthy controls at the time of their inclusion in the study (p = 0.155, p = 0.189, p = 0.198, respectively). In addition, a significant decrease was detected in the left, right and mean temporal muscle thicknesses of patients with acromegaly before and after treatment. While the temporal muscle thickness at the time of diagnosis was thicker in patients with acromegaly receiving surgical + medical treatment than in patients receiving exclusively surgical treatment, statistical significance was only found in the left temporal muscle thickness (p = 0.042). ConclusionTemporal muscle thickness was found to be associated with treatment modalities in patients with acromegaly.

Prognostic factors of visual outcome in central serous chorioretinopathy treated with subthreshold micropulse laser therapy.

Analyze the prognostic factors of visual outcome in central serous choriretinopathy (CSC) treated with subthreshold micropulse laser (SML) therapy through the most fundamental medical history and clinical examinations. It was a retrospective clinical study. We collected the most fundamental medical history and clinical examinations of CSC patients who received SML treatment, including visual acuity (VA) and spectral-domain optical coherence tomography (SD-OCT) of macular. Eyes were divided into two groups according the change of central macular thickness (CMT) before and one month after SML: CMT improvement and CMT deterioration group; divided into three groups according the change of VA: VA improvement, VA stability and VA decline group. Seventy-eight patients (eighty-three eyes) were enrolled. The baseline CMT was 339.83 ± 115.72μm, and the baseline VA was 0.43 ± 0.36. One month after SML, CMT was 281.13 ± 121.48μm, had a significant statistical improvement (p = 0.000); and VA was 0.46 + 0.42, had no significant statistical difference compared to baseline VA (p = 0.114). CMT of sixty-three eyes (75.90%) declined, and twenty eyes (24.10%) increased; VA of thirty-one eyes (37.35%) improved, fourteen eyes (16.87%) remained unchanged, and thirty-eight eyes (45.78%) declined. CMT and VA of twenty-seven eyes (32.53%) were both improved, and eleven eyes (13.25%) were both deteriorated. VA one month after SML was statistically correlated with age (p = 0.000), baseline VA (p = 0.000), and baseline CMT (P = 0.002). CMT and VA both improved one month after SML, and the improvement of CMT was more significant than VA. Elder age and poorer baseline vision indicated poorer VA one month after SML, while higher baseline CMT indicated better VA one month after SML.

Temporal Augmentation Effect of Reduction Malarplasty: Application of our Bracing Technique with Zygomatic Arch Elevation.

A broad midface is usually accompanied by temporal depression. Traditional reduction malarplasty may visually improve the temporal depression by the inward reduction of zygomatic arch, but also has a high risk of soft tissue sagging. Our bracing technique has been reported to have an anti-sagging effect and may have a temporal augmentation effect as observed during our long-term clinical practice. Data of patients who received reduction malarplasty with our bracing technique from September 2015 to July 2023 were retrospectively collected. The pre-op and post-op CT images of those who met the inclusion criteria were used for three-dimensional reconstruction and measurements of the thickness and volume of the temporal soft tissue as well as the elevation distance of zygomatic arch. Fifty-eight patients with an average follow-up of 18.4 ± 9.1months were included. Despite mild thinning of the temporalis muscle after reduction malarplasty, the overall thickness of the temporal soft tissue significantly increased due to the significant thickening of the temporal adipose-fascial layer. There was a 0.5ml-increase in the temporal volume although without statistical difference. No significant correlation was detected between the elevation distance of zygomatic arch and the temporal thickness or volume change. The bracing technique of reduction malarplasty not only plays an anti-sagging role, but also has a temporal augmentation effect through the superior bracing by the elevation and rigid fixation of the zygomatic arch. It adds brilliance to the traditional technique and can be suggested especially when the patients are disturbed by temporal depression. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Five-year changes in retinal nerve fibre layer thickness in the adult population: a population-based cohort study.

Distinguishing between the pathological thinning of the retinal nerve fibre layer (RNFL) and age-related reduction requires a comprehensive understanding of the longitudinal changes in RNFL thickness within a healthy population. To determine five-year changes in RNFL thickness and associated factors in people aged 45-69 years. This report pertains to the second and third phases of the Shahroud Eye Cohort Study. Participants were recruited by a multi-stage cluster sampling in Shahroud, Iran. Data on demographic details, visual acuity, non-cycloplegic refraction, and slit-lamp biomicroscopy were collected. High-definition optical coherence tomography was employed for retinal imaging. A total of 1,524 eyes from 908 participants were examined. The average RNFL thickness was 92.2 ± 8.5 (95% CI: 91.6 to 92.8) and 93.1 ± 8.7 μm (95% CI: 92.5 to 93.7) in the first and second phases with a five-year mean change of 0.95 ± 4.15 μm (95% CI: 0.70 to 1.20). The RNFL thickness mean changes in the superior, inferior, nasal, and temporal quadrants were 2.51 ± 7.86 (95% CI: 2.01 to 3.02), 2.93 ± 7.39 (95% CI: 2.56 to 3.29), -0.53 ± 6.15 (95% CI: -0.84 to -0.21), and -1.01 ± 4.67 μm (95% CI: -1.27 to -0.75), respectively. The five-year changes in average RNFL thickness were inversely correlated with axial length (β = -0.69, p < 0.001), mean keratometry (β = -0.37, p = 0.017), and baseline RNFL thickness (β = -0.617, p < 0.001). In hyperopic individuals, the increase in average RNFL thickness (β = 0.65, p = 0.012) was significantly greater than in those with emmetropia. Macular volume (β = 1.65, p < 0.001) showed a direct association with five-year changes in average RNFL thickness. Over 5 years, RNFL thickness changes were clinically insignificant in the normal population. The mean RNFL thickness seems to remain stable unless there is ocular disease. However, increased axial length and steeper keratometric readings were linked to RNFL thinning. Those with thicker RNFL measurements were at higher risk of thinning over time.

Soft and hard tissue evaluation for vestibular socket therapy of immediately placed implants in infected and non-infected sockets: a 1-year prospective cohort study

BackgroundImmediate implant placement using vestibular socket therapy (VST) proved to offer a successful treatment option in compromised sockets. However, the presence of active signs infection complicates immediate implants in sockets with defective labial plates, due to the possible contamination of the implant or the bone graft with existing infected tissues or oral environment via the fistula. This study, therefore, aims to explore the success of immediate implant placement using VST in managing infected compromised sockets.MethodsWe included 26 age- and sex-matched patients with 41 implants sites. Thirteen patients had 19 infected (group I) and 13 had 21 non-infected type 2 sockets (group N). Both groups were treated using vestibular socket therapy (VST) and a 6-day protocol. Implant survival, changes in facial bone thickness, and mid, mesial, and distal mucosal levels were evaluated 1 year after implant placement. The Mann–Whitney U test was used to compare both groups. Furthermore, the Wilcoxon signed-rank test was used to study changes with time within each group. The statistical significance level was set at P < 0.05.ResultsAll implants survived; no significant difference was found between groups N and I regarding apical, mid, and crestal bone thickness and soft tissue level, except at the mesial papilla, where the recession was significantly more in group N than in group I. Changes over time were statistically significant in the apical, mid, and crestal bone thickness in both groups. The mean bone thickness gain ranged from 0.85 to 2.4 mm and 0.26–1.63 mm in groups I and N, respectively. Additionally, the mean mucosal recession ranged from 0.29 to 0.51 mm and 0.39–1.47 mm in groups I and N, respectively.ConclusionWithin the limitations of this study immediate implant placement in type II infected sockets using the 6-day protocol and VST achieved 100% implant survival, while maintaining the regenerated facial bone thickness with minimal mucosal recession.Trial registrationThe protocol for this study was registered on clinicaltrials.gov at 3/10/2021 (registration number NCT04787224).

A radar backscatter simulation of a forest canopy using 3D physical structures derived from LiDAR scanning

ABSTRACT This study aims to explore the forest aboveground biomass relationship to C-band backscatter. A one-hectare area in Wytham Woods, located west of Oxford, was selected for this research. The area has a total of 525 trees of seven different tree species. The Michigan Microwave Canopy Scattering Model (MIMICS), a two-layer radiative transfer model, was applied to simulate canopy backscatter responses in this deciduous UK forest. Model parameters related to forest structure were derived from previously published terrestrial laser (LiDAR) data. Simulated backscatter was performed for co-polarized and cross-polarized modes at a C-band frequency range and incidence angles (20° to 45° at 5° increments). The research includes five objectives: i) backscatter sensitivity analysis from the variation of different model parameters; ii) backscatter seasonal effect under spring–summer (leaf-on) and autumn–winter (leaf-off) periods; iii) backscatter comparison between species as well as between simulated and satellite observations in a spatial pattern; iv) relationship between simulated backscatter and aboveground biomass; and v) relationship between MIMICS forest structure parameters and simulated backscatter. Sensitivity analysis results showed significant differences in backscatter from changes in leaf distribution, leaf thickness and water content (leaf, trunk and soil) for both polarization modes in leaf-on scenarios. Leaf-off scenarios presented significant differences from changes in branch distribution but only for the co-polarized mode. Seasonal variations presented significant backscatter differences between spring–summer and autumn–winter scenarios; additionally, backscatter differences among species for each seasonality in the co-polarized mode were observed. The computation of the grid resolution (20 m × 20 m) showed a range of backscatter values depending on the grid and incidence angle. Higher backscatter values were observed for the satellite data than for the simulated data. Finally, the aboveground biomass and the MIMICS input parameters presented high random variability and little systematic co-variation with the total backscatter on both simulated seasons, suggesting that more robust allometric equations for biomass estimation are required.

Optical Coherence Tomography Image Analysis for Detection of Alzheimer’s Disease: A Comprehensive Structured Review

Optical Coherence Tomography (OCT) has emerged as a promising non-invasive imaging modality for the early detection of Alzheimer’s Disease (AD). This systematic literature review aims to consolidate current research on OCT image analysis for AD detection, addressing the growing need for early and accurate diagnostic tools. Despite the advances in neuroimaging, early diagnosis of AD remains challenging due to its asymptomatic nature in initial stages and the invasiveness of traditional methods. To achieve this, we conducted an extensive search of related articles from reputable databases (Scopus and Web of Science), focusing on studies published between 2022-2024. The flow of study was based on PRISMA framework. The database found (n = 29) final primary data. This review was divided into three themes, (1) retinal and ocular biomarkers for AD, (2) optical coherence tomography angiography (OCTA) and imaging techniques, and (3) machine learning and computational approaches for Alzheimer’s disease diagnosis. Key findings include the enlargement of the periarteriole capillary-free zone and changes in retinal nerve fibre layer thickness as potential AD biomarkers. Based on the review, the implementation of image analysis for OCT images have shown substantial potential for AD detection. By evaluating the past studies, gaps for the current research were discovered including the need for larger, more diverse cohorts and longitudinal studies to validate these biomarkers. In summary, detection of AD is possible through thorough OCT image analysis, but further research could be suggested to enhance its clinical applicability and reliability.

Attenuation of 1-chloro-2,4-dinitrobenzene-induced inflammation in atopic dermatitis-like skin lesions in rats by a pyrrole containing FELL-NH 2 bioconjugate: Cannabinoid receptor type 1 involvement

Atopic dermatitis (AD) is a chronic inflammatory skin condition of significant health and social importance, which justifies the search for new means of treatment. Since the endogenous cannabinoid system appears to be involved in the pathogenesis of AD, the proposed article summarizes the clinical impact on skin inflammation in a rat model of 1-chloro-2,4-dinitrobenzene-induced atopic dermatitis-like condition after exogenous systemic administration of the cannabinoid receptor type 1 (CB1r) agonist anandamide, as well as after local treatment with a newly synthesized pyrrole moiety containing bioconjugate of FELL tetrapeptide with CB1r-dependent analgesic activity. The changes in skin lesions and ear thickness were estimated along with the CB1r expression immunohistochemically determined on skin punch biopsies. The results showed attenuation of skin lesions by anandamide and lack of positive effect after introduction of CB1r antagonist, accompanied by a change in CB1r expression, suggesting the involvement of the cannabinoid system in the defensive functions of the skin. The topically applied newly synthesized bioconjugate also favorably affected skin manifestations of inflammation, but without a change in CB1r expression, suggesting the involvement of other mechanisms in the reported effects.

Changes in choroidal thickness and blood flow in response to form deprivation-induced myopia and repeated low-level red-light therapy in Guinea pigs.

To evaluate ocular refractive development, choroidal thickness (ChT) and changes in choroidal blood flow in form-deprived myopia (FDM) Guinea pigs treated with repeated low-level red-light (RLRL) therapy. Twenty-eight 3-week-old male tricolour Guinea pigs were randomised into three groups: normal controls (NC, n = 10), form-deprived (FD, n = 10) and red light treated with form-deprivation (RLFD, n = 8). Interocular refraction and axial length (AL) changes were monitored. Optical coherence tomography angiography (OCTA) measured choroidal thickness, vessel area density, vessel skeleton density and blood flow signal intensity (flux) in the choriocapillaris and medium-large vessel layers. The experimental intervention lasted 3 weeks. At week 3, the FD group had higher myopia and longer axial length than the NC group (all p < 0.001). The RLFD group had higher hyperopia and shorter axial length than the FD group (all p < 0.001). At week 1, the NC group had a thicker choroidal thickness than the FD group (p < 0.05). At weeks 2 and 3, the RLFD group had a thicker choroidal thickness than the FD group (p = 0.002, p < 0.001, respectively). Additionally, the NC group had higher vessel area density, vessel skeleton density and flux in the choriocapillaris layer than the FD group at the three follow-up time points (all p < 0.05). At week 3, the vessel skeleton density and flux were higher in the RLFD group than in the FD group (all p < 0.05). Correlation analysis results showed that weekly changes in refraction and choroidal thickness were negatively correlated with changes in axial length (all p < 0.05). Choroidal thickness changes were positively correlated with alterations in the vessel area density, vessel skeleton density and flux in the choriocapillaris layer, as well as vessel skeleton density and flux changes in the medium-large vessel layers (all p < 0.05). Repeated low-level red-light (RLRL) therapy retards FDM progression in Guinea pigs, potentially through increased choroidal blood flow in the choriocapillaris layer.

Morphological Evaluation of Corpus Callosum Atrophy Over Time in Relapsing Remitting Multiple Sclerosis

Objective: Multiple sclerosis (MS) is a chronic central nervous system (CNS) disease that generally affects young adults and is marked by inflammation, demyelination, and neurodegeneration. Magnetic resonance imaging (MRI) is widely used diagnosis tool for relapsing remitting MS (RRMS). Corpus callosum (CC), the largest commissural tract in brain which is associated with both cognitive and physical impairment by atrophy in MS. Our study aimed to evaluate CC in RRMS patients using MR images and compare it to measurements from healthy controls within the same age. Methods: We manually measured changes in CC thickness in T1 brain MR images of RRMS patients in 2017, 2019, and 2022. Results: Our results showed that control group had greater thickness, length, and index values in all CC sections compared to patient group. Additionally, a significant difference was observed in thickness of genu and splenium sections and CC index between patient and control groups. However, no significant difference was detected in truncus part of CC or overall CC length. CC measurements in patient group decreased over time, with 1st MRI showing greater values than 2nd and 3rd MRI scans. Furthermore, there was a statistically significant difference in thickness of truncus part of CC and volume values of subcortical areas between 2nd-3rd and 1st-3rd MRI measurements. Conclusion: As a result of these findings, our study provides important information about changes in CC measurements for MS patients.

Comparison of visual acuity outcome and choroidal thickness variation of intravitreal ranibizumab injection for myopic choroidal neovascularization with or without dome-shaped macula

BackgroundTo investigate the visual acuity outcome and choroid thickness (CT) change after intravitreal ranibizumab in highly myopic eyes with or without dome-shaped macula (DSM) in Chinese patients. MethodsThis retrospective, observative study included 80 treatment-naive eyes (80 patients), which received ranibizumab according to the 1+PRN protocol. The best corrective visual acuity (BCVA) and CT change were compared between eyes with or without DSM. ResultsThere was no significant difference between eyes with or without DSM in BCVA and central macular thickness (CMT). The recurrent rate was not different between the two groups during the first year of treatment. The CT was significantly thinner in eyes with DSM than in eyes without DSM before treatment (median 40.00um versus 71.00um), at 1 month after treatment (median 31.00um versus 65.50um), and in the last follow up (median, 32.00um versus 65.00um) (p = 0.0101). Axial length (AL) was longer in eyes with DSM than those without DSM (median, 29.17 mm versus 28.10 mm) before treatment, and in the last follow up (median, 29.44 mm versus 28.20 mm) (p = 0.0055). The CT was significantly correlated with AL (p < 0.0001). ConclusionsNo difference was found in visual outcome between eyes with or without DSM. The visual acuity significantly improved at 1 month after ranibizumab injection and it was recovery sooner in extrafoveal choroidal neovascularization (CNV) group than in subfoveal CNV group. The CT was thinner in eyes with DSM, which was significantly correlated with AL.

Prevalence and characteristics of minimal pleural fluid on screening chest MRI

BackgroundMinimal pleural fluid is often seen incidentally on chest MRI. However, its prevalence and clinical characteristics remain unknown. MethodsThis retrospective observational study included 2726 participants who underwent comprehensive medical check-ups for screening, including chest CT and MRI, and transthoracic echocardiography between March 2018 and February 2019. Pleural fluid on MRI was manually measured for maximum thickness. Its distribution, change over time, and relevance to participant characteristics were analyzed. The pulmonary function data of 82 participants and their associations with fluid were also analyzed. ResultsOf the 2726 participants (mean age ± standard deviation, 59 ± 11 years), 2009 (73.7%) had minimal pleural fluid (thickness, 1–9 mm) on either side, with right-sided fluid being more frequent than left-sided fluid (P < 0.001). Negligible changes in fluid thickness were observed one year later. The following parameters were associated with less fluid: age, ≥65 years (P < 0.001); male sex (P = 0.006); current smoking (P < 0.001); body mass index, ≥25 kg/m2 (P < 0.001); and mean arterial pressure, ≥100 mmHg (P = 0.01), whereas a ratio between early mitral inflow velocity and mitral annular early diastolic velocity>14 was associated with more fluid (P = 0.01). The presence of fluid was an independent explanatory variable for a higher percentage of predicted vital capacity (P = 0.048). ConclusionsMRI was highly sensitive in detecting minimal pleural fluid. Pleural fluid found on MRI for health screening was assumed to be physiological and fluid thickness at the steady state might be variable among participants depending on age, sex, smoking habits, body shape, blood pressure, and cardiac diastolic capacity.

Speech motor impairment in ALS is associated with multiregional cortical thinning beyond primary motor cortex.

Cortical thinning is well-documented in individuals with amyotrophic lateral sclerosis (ALS), yet its association with speech deterioration remains understudied. This study characterizes anatomical changes in the brain within the context of speech impairment patterns in individuals with ALS, providing insight into the disease's multiregional spread and biology. To evaluate patterns of cortical thickness in speakers with ALS with and without functional speech changes compared to healthy controls (HCs) using whole-brain and region of interest (ROI) analyses. Forty individuals with ALS and 22 HCs underwent a T1-weighted 3-Tesla magnetic resonance imaging (MRI). Individuals with ALS were divided into two groups based on the preserved speech [ps-ALS] (n = 18) or deteriorated speech [ds-ALS] (n = 22) as measured by the ALSFRSF-R speech subscore (=4 or <4 points, respectively). Sixteen a priori-defined and automatically segmented cortical and subcortical brain ROIs were selected based on their previously documented roles in speech production. Two cortical thickness analyses were performed: (1) group-level whole-brain surface-based analyses and (2) group-level ROI analyses. A case study of 6 ALS individuals examined the cortical thickness, and their speech was characterized using quantitative and qualitative measures. Based on the group-level whole-brain surface-based analyses, the ds-ALS group demonstrated significant cortical thinning compared to HCs in the left primary motor and somatosensory cortices and the right inferior parietal lobe with its adjacent lateral occipital cortical regions. The ps-ALS group demonstrated no significant cortical thinning compared to HCs. Based on the group-level ROI analyses, the ds-ALS group demonstrated significant cortical thinning compared to HCs in bilateral middle motor cortices, right posterior dorsal premotor cortex, and left anterior cingulate cortex. The case study analysis revealed that ALS speakers with speech features characteristic of spastic dysarthria exhibited cortical thinning, while those with speech features characteristic of flaccid dysarthria did not. Individuals with ALS have anatomical changes involving multiregional neocortical areas beyond the primary motor cortex that may manifest as subjective (i.e., clinical judgment) and objective (i.e., speaking rate) changes in speech production. Further longitudinal work in ALS is needed to better understand the link between MRI cortical thickness changes and bulbar dysfunction.

Corneal Epithelial Remodeling After Hyperopic SMILE: A 4-Year Study.

The purpose of this study was to investigate dynamic changes in corneal epithelial thickness (ET) after hyperopic small incision lenticule extraction (SMILE). This observational study included 18 eyes of 16 patients who were scheduled for hyperopic SMILE. High-resolution spectral-domain optical coherence tomography and a custom image segmentation algorithm were applied to measure corneal dynamic ET over a central 6 mm area. ET was analyzed among different corneal sectors (central, pericentral, and peripheral) at baseline and multiple postoperative time points (1 day, 1 month, 6 months, 2 years, and 4 years). Correlation analysis was performed between ET changes and preoperative and intraoperative parameters. The mean spherical equivalent of hyperopia correction was +2.64 ± 1.00 D, and the average age of enrolled 16 patients was 32.4 ± 10.8 years. At the last follow-up, 72% of eyes kept or improved corrected distance visual acuity, with 2 eyes that lost 2 lines. 72% of eyes were within ±1.0 D of target refraction, and 56% were within ±0.5 D. Average ET decreased by 11.0% (5.9 ± 2.3 μm) from 53.2 ± 3.5 μm to 47.4 ± 4.2 μm 4 years postoperatively (P<0.001). The ET at center 2 mm decreased most significantly by 14.5% (7.9 ± 2.9 μm), followed by the pericentral area by 10.5% (5.6 ± 2.3 μm). ET and front corneal curvature stabilized 1 month after surgery. No correlation was found between refraction regression and ET changes. Hyperopic SMILE induced significant central ET thinning. ET remodeling in the 6 mm area stabilized after 1 month and did not underlie refractive changes.

Walking recovers cartilage compressive strain in vivo

BackgroundArticular cartilage is a fiber reinforced hydrated solid that serves a largely mechanical role of supporting load and enabling low friction joint articulation. Daily activities that load cartilage, lead to fluid exudation and compressive axial strain. To date, the only mechanism shown to recover this cartilage strain in vivo is unloading (e.g., lying supine). Based on recent work in cartilage explants, we hypothesized that loaded joint activity (walking) would also be capable of strain recovery in cartilage. MethodsEight asymptomatic young adults performed a fixed series of tasks, each of which was followed by magnetic resonance imaging to track changes in their knee cartilage thickness. The order of tasks was as follows: 1) stand for 30 ​min, 2) walk for 10 ​min, 3) stand for 30 ​min, and 4) lie supine for 50 ​min. The change in cartilage thickness was used to compute the axial cartilage strain. ResultsStanding produced an average axial strain of −5.1 ​% (compressive) in the tibiofemoral knee cartilage, while lying supine led to strain recovery. In agreement with our hypothesis, walking also led to cartilage strain recovery. Interestingly, the recovery rate during walking (0.19 ​% strain/min) was nearly 3-fold faster than lying supine (0.07 ​% strain/min). ConclusionsThis study represents the first in vivo demonstration that joint activity is capable of recovering compressive strain in cartilage. These findings indicate that joint activities such as walking may play a key role in maintaining and recovering cartilage strain, with implications for maintaining cartilage health and preventing or delaying cartilage degeneration.

Lifelong Changes in the Choroidal Thickness, Refractive Status, and Ocular Dimensions in C57BL/6J Mouse.

To investigate the changes in choroidal thickness (ChT), refractive status, and ocular dimensions in the mouse eye in vivo using updated techniques and instrumentation. High-resolution swept-source optical coherence tomography (SS-OCT), eccentric infrared photoretinoscopy, and custom real-time optical coherence tomography were used to analyze choroidal changes, refractive changes and ocular growth in C57BL/6J mice from postnatal day (P) 21 to month 22. The ChT gradually increased with age, with the thickest region in the para-optic nerve head and thinning outward, and the temporal ChT was globally thicker than the nasal ChT. Retinal thickness remained stable until 4months and subsequently decreased. The average spherical equivalent refraction error was -4.81 ± 2.71 diopters (D) at P21, which developed into emmetropia by P32, reached a hyperopic peak (+5.75±1.38D) at P82 and returned to +0.66 ± 1.86 D at 22months. Central corneal thickness, anterior chamber depth, lens thickness, and axial length (AL) increased continuously before 4months, but subsequently exhibited subtle changes. Vitreous chamber depth decreased with lens growth. ChT was correlated significantly with the ocular parameters (except for retinal thickness) before the age of 4months, but these correlations diminished after 4months. Furthermore, for mice younger than 4months, the difference in the ChT, especially temporal ChT, between the two eyes contributed most to that of axial length and spherical equivalent refraction error. Four months could be a watershed age in the growth of mouse eyes. Large-span temporal recordings of refraction, ocular dimensions, and choroidal changes provided references for the study of the physiological and pathological mechanisms responsible for myopia.

Temporal Changes in the Retinal Pigment Epithelium-Bruch's Membrane Complex Thickness After Autologous Retinal Transplantation in Myopic Eyes.

To investigate the association between the thickness of the retinal pigment epithelium (RPE)-Bruch's membrane (BM) complex and the development of retinal autograft edema as a postoperative complication following autologous retinal transplantation (ART). This retrospective study examined data from 28 eyes of 28 patients (14 males, 14 females; mean age, 61.5 ± 19.8 years) who underwent ART and were followed for 1 year. The RPE-BM complex thickness was measured 2000 µm from the fovea using Image J software. Additionally, the graft blood flow was also evaluated by optical coherence tomography angiography and fluorescein angiography. Macular hole (MH) diameters ranged from 711.2 ± 251.9 µm to 1299.9 ± 333.0 µm, with MH closure achieved in all patients. RPE-BM complex thickness decreased by 4.17 µm at 6 months and 4.34 µm at 1 year, showing significant differences from preoperative measurements (29.88 ± 4.99 µm; 6 months: 95% confidence interval [CI], 1.62-6.71, P = 0.0018; 1 year: 95% CI, 2.03-6.65 µm, P = 0.00044). The decrease was significantly greater in the edema-positive group (95% CI, -8.33 to -0.82, P = 0.020). Furthermore, the rates of ellipsoid zone (EZ) recovery, alignment of neurosensory layers (ANL), and graft reperfusion were lower in the edema-positive group (EZ, P = 0.017; ANL, P = 0.0098; reperfusion, P = 0.039). After ART, RPE-BM complex thickness decreases, particularly in cases with postoperative edema, suggesting a potential relationship between RPE function and postoperative outcomes, highlighting the importance of monitoring RPE-BM complex thickness after surgery.

Longitudinal Imaging of the Foveal Cone Mosaic in CNGA3-Associated Achromatopsia.

The purpose of this study was to assess the natural history of the foveal cone mosaic in CNGA3-associated achromatopsia (ACHM). Thirteen eyes from 10 genetically confirmed patients underwent longitudinal imaging with optical coherence tomography (OCT) and non-confocal split detection adaptive optics scanning light ophthalmoscopy (AOSLO). OCT scans assessed outer nuclear layer (ONL) thickness, foveal ellipsoid zone (EZ) disruption, and foveal hypoplasia. AOSLO images were analyzed to calculate peak foveal cone density (PCD) and mean inter-cell distance (ICD) between cones. Mixed effects models were used to analyze the rate of annual change of PCD and ICD. Mean (±SD) age at visits was 29 ± 10 years, with a follow-up of 2.6 ± 1 years. There was no change in ONL thickness, degree of EZ disruption, or foveal hypoplasia over the follow-up period. We also observed a stable foveal cone mosaic using AOSLO imaging, with no significant change in PCD or ICD. Mean PCD was 15,346 cones/mm² at the mean age of 29 years old (cf. 64,000-324,000 cones/mm² in previously reported healthy controls), with a mean rate of change of -117.79 cones/mm² (0.8%) per year, P = 0.130. Mean ICD at the mean age was 13.82 µm, with a rate of change of 0.17 µm per year, P = 0.83. CNGA3-associated ACHM displays stable foveal cone structure over time with a similar rate of change to CNGB3-associated ACHM (2% decline per year). The stable PCD, small cohort, and large variability within the cohort means significant age associations were not detected.

Techniques to mitigate membrane displacement for vacuum-membrane solar-dish facets

The prospects of a multifaceted vacuum-membrane solar dish concentrator are considered in this work. The membrane depths of these facets can shift slightly due to varying ambient conditions throughout an operational day, leading to major focal point shifts and a reduced overall efficiency. The purpose of this work was to experimentally investigate different methods of membrane displacement mitigation. A controlled-environment (indoor) enclosure was employed to examine the effects of static ambient conditions, allowing for the independent manipulation of the surrounding pressure and temperature. Various manufacturing techniques were also investigated within the controlled-environment enclosure, which included alterations in pretension, changes in membrane thickness and adjustments to overall facet sizes. Furthermore, outdoor tests were conducted to determine how solar radiation and convection affected membrane displacement as well as to investigate the performance of various membrane depth control strategies using an Arduino Uno microcontroller. The indoor results showed that opting for a small facet would minimize membrane displacement. The results were supported by material tests and a finite element analysis. The outdoor test results indicated that solar radiation and wind affected the internal temperature and consequently also affected the membrane depth. Furthermore, a focus control system maintaining a constant differential pressure across the membrane achieved the required accuracy of ±2 mm membrane displacement limitation. However, another focus control system consisting of a Hall effect module actively monitoring membrane depth emerged as the most effective, with an increase of about 0.09 mm and a decrease of approximately 0.02 mm from an initial depth of 10 mm. This level of stability with a focus control system will ensure that the facet maintains a consistent optical performance, ultimately advancing the reliability and efficiency of low-cost vacuum-membrane technology.