Magnification Differences Research Articles

Correction algorithm for misalignment and magnification difference of focused and defocused images in phase diversity image reconstruction

Correction algorithm for misalignment and magnification difference of focused and defocused images in phase diversity image reconstruction

Exoscope and Supermicrosurgery: Pros and Cons of 3D Innovation in Lymphatic Surgery.

Background: The surgical treatment of lymphedema has seen advancements in recent years, with supramicrosurgical lymphaticovenular anastomosis (sLVA) gaining global acceptance. The integration of 3D exoscopes into microsurgery offers potential ergonomic and educational benefits. However, systematic evaluation of their efficacy in sLVA remains limited. Methods: A retrospective cross-sectional study was conducted comparing the use of 3D exoscopes to conventional operating microscopes (OM) in sLVA surgeries. Patient data from January 2019 to January 2024 were reviewed, with demographic, clinical, and surgical outcome variables analyzed. Ergonomic assessments were performed using Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA), while surgeon satisfaction was evaluated through the Microsurgical Intraoperative Satisfaction and Comfort questionnaire (MISCq). Results: An analysis of 25 patients (OM group: n = 14; exoscope group: n = 11) revealed no significant differences in age, sex, etiology, or surgical site between the two groups. Surgical time, number of incisions, and number of anastomoses showed nonsignificant variations between the OM and exoscope groups. Ergonomic assessments indicated potential benefits with exoscope use, particularly for the assistant surgeon. Survey results demonstrated comparable levels of surgeon satisfaction with both instruments, with no significant differences in image quality, contrast, illumination, magnification, visual field, ergonomic maintenance, or stereoscopic orientation. Conclusions: The study suggests that 3D exoscopes are a valuable tool for sLVA supermicrosurgery, offering comparable outcomes to traditional microscopes with potential ergonomic advantages. Their integration into microsurgical practice may contribute to improved surgical comfort and team performance. Further research is warranted to confirm these findings and explore additional factors such as cost-effectiveness and long-term patient outcomes.

Radiographical magnification of the shoulder region

Abstract Background Calibration of shoulder radiographs is required for accurate preoperative planning. Current practice mostly uses an empirical fixed calibration factor of 5%, and limited information is available about how the magnification of the glenohumeral region differs among patients. This retrospective observational study analyzed the patient-specific magnification factor in total shoulder arthroplasty. Methods Radiographs of 94 patients with unilateral total shoulder arthroplasty (SMR Reverse Shoulder System, Lima Ltd., San Daniele del Friuli, Italy) were obtained from archives. The reverse humeral body diameter was used as internal reference. The measured radiographical magnifications were correlated with the patients’ sex, weight, and height. Results The average magnification factor of the glenohumeral region was 11.9% (standard deviation: 3.2%, range: 5.7–20.3%). No statistically significant difference in radiographic magnification was found between the male and the female patients. The magnification factor was higher in patients with higher weight (p < 0.05), but the explanatory power of the model was weak (R = 0.09). Conclusions The observed radiographic magnification was considerably higher than a commonly used fixed calibration factor of 5% and exhibited considerable variability among the patients. Therefore, standard radiographs might not be appropriate for accurate preoperative templating, and we recommend using either computer tomography data or calibrating radiographs through external calibration markers for each patient.

Multimodal in-vivo maps as a tool to characterize retinal structural biomarkers for progression in adult-onset Stargardt disease.

To characterize retinal structural biomarkers for progression in adult-onset Stargardt disease from multimodal retinal imaging in-vivo maps. Seven adult patients (29-69 years; 3 males) with genetically-confirmed and clinically diagnosed adult-onset Stargardt disease and age-matched healthy controls were imaged with confocal and non-confocal Adaptive Optics Scanning Light Ophthalmoscopy (AOSLO), optical coherence tomography (OCT), fundus infrared (FIR), short wavelength-autofluorescence (FAF) and color fundus photography (CFP). Images from each modality were scaled for differences in lateral magnification before montages of AOSLO images were aligned with en-face FIR, FAF and OCT scans to explore changes in retinal structure across imaging modalities. Photoreceptors, retinal pigment epithelium (RPE) cells, flecks, and other retinal alterations in macular regions were identified, delineated, and correlated across imaging modalities. Retinal layer-thicknesses were extracted from segmented OCT images in areas of normal appearance on clinical imaging and intact outer retinal structure on OCT. Eccentricity dependency in cell density was compared with retinal thickness and outer retinal layer thickness, evaluated across patients, and compared with data from healthy controls. In patients with Stargardt disease, alterations in retinal structure were visible in different image modalities depending on layer location and structural properties. The patients had highly variable foveal structure, associated with equally variable visual acuity (-0.02 to 0.98 logMAR). Cone and rod photoreceptors, as well as RPE-like structures in some areas, could be quantified on non-confocal split-detection AOSLO images. RPE cells were also visible on dark field AOSLO images close to the foveal center. Hypo-reflective gaps of non-waveguiding cones (dark cones) were seen on confocal AOSLO in regions with clinically normal CFP, FIR, FAF and OCT appearance and an intact cone inner segment mosaic in three patients. Dark cones were identified as a possible first sign of retinal disease progression in adult-onset Stargardt disease as these are observed in retinal locations with otherwise normal appearance and outer retinal thickness. This corroborates a previous report where dark cones were proposed as a first sign of progression in childhood-onset Stargardt disease. This also supports the hypothesis that, in Stargardt disease, photoreceptor degeneration occurs before RPE cell death.

Correction Method for Optical Scaling of Fundoscopy Images: Development, Validation, and First Implementation.

Although fundus photography is extensively used in ophthalmology, refraction prevents accurate distance measurement on fundus images, as the resulting scaling differs between subjects due to varying ocular anatomy. We propose a PARaxial Optical fundus Scaling (PAROS) method to correct for this variation using commonly available clinical data. The complete optics of the eye and fundus camera were modeled using ray transfer matrix formalism to obtain fundus image magnification. The subject's ocular geometry was personalized using biometry, spherical equivalent of refraction (RSE), keratometry, and/or corneal topography data. The PAROS method was validated using 41 different eye phantoms and subsequently evaluated in 44 healthy phakic subjects (of whom 11 had phakic intraocular lenses [pIOLs]), 29 pseudophakic subjects, and 21 patients with uveal melanoma. Validation of the PAROS method showed small differences between model and actual image magnification (maximum 3.3%). Relative to the average eye, large differences in fundus magnification were observed, ranging from 0.79 to 1.48. Magnification was strongly inversely related to RSE (R2=0.67). In phakic subjects, magnification was directly proportional to axial length (R2=0.34). The inverse relation was seen in pIOL (R2=0.79) and pseudophakic (R2=0.12) subjects. RSE was a strong contributor to magnification differences (1%-83%). As this effect is not considered in the commonly used Bennett-Littmann method, statistically significant differences up to 40% (mean absolute 9%) were observed compared to the PAROS method (P<0.001). The significant differences in fundus image scaling observed among subjects can be accurately accounted for with the PAROS method, enabling more accurate quantitative assessment of fundus photography.

Design of a Spaceborne, Compact, Off-Axis, Multi-Mirror Optical System Based on Freeform Surfaces

Based on the application requirements of high spectral resolutions, high spatial resolutions and wide swatches, a new-generation, high-performance, spaceborne, hyperspectral imaging spectrometer (NGHSI) with a spatial resolution of 15 m and a swatch of 90 km is proposed. The optical system of the NGHSI has a focal length of 1128 mm, an F-number of three, a field of view (FOV) of 7.32° and a slit length of 144 mm. A new off-axis, multi-mirror telescope structure with intermediate images is put forward, which solves the design problem that realizes secondary imaging and good telecentricity at the same time. And a new off-axis lens-compensation Offner configuration is adopted to address the challenge of the high-fidelity design of spectral imaging systems with long slit lengths. The relationship between X-Y polynomials and aberration coefficients is analyzed, and the X-Y polynomial freeform surfaces are used to correct the off-axis aberrations. The design results show that the image quality of the telescope system is close to the diffraction limit. The smile, known as the spectral distortion along the line, and keystone, which is the magnification difference for different wavelengths, of the spectral imaging system are less than 1/10 pixel size. The complete optical system of the NGHSI, including the telescope system and the spectral imaging system, has excellent imaging quality and the layout is compact and reasonable, which realizes the miniaturization design.

Three-Dimensional Pore Structure Characterization of Bituminous Coal and Its Relationship with Adsorption Capacity.

Bituminous coal reservoirs exhibit pronounced heterogeneity, which significantly impedes the production capacity of coalbed methane. Therefore, obtaining a thorough comprehension of the pore characteristics of bituminous coal reservoirs is essential for understanding the dynamic interaction between gas and coal, as well as ensuring the safety and efficiency of coal mine production. In this study, we conducted a comprehensive analysis of the pore structure and surface roughness of six bituminous coal samples (1.19% < Ro,max < 2.55%) using various atomic force microscopy (AFM) techniques. Firstly, we compared the microscopic morphology obtained through low-pressure nitrogen gas adsorption (LP-N2-GA) and AFM. It was observed that LP-N2-GA provides a comprehensive depiction of various pore structures, whereas AFM only allows the observation of V-shaped and wedge-shaped pores. Subsequently, the pore structure analysis of the coal samples was performed using Threshold and Chen's algorithms at ×200 and ×4000 magnifications. Our findings indicate that Chen's algorithm enables the observation of a greater number of pores compared to the Threshold algorithm. Moreover, the porosity obtained through the 3D algorithm is more accurate and closely aligns with the results from LP-N2-GA analysis. Regarding the effect of magnification, it was found that ×4000 magnification yielded a higher number of pores compared to ×200 magnification. The roughness values (Rq and Ra) obtained at ×200 magnification were 5-14 times greater than those at ×4000 magnification. Interestingly, despite the differences in magnification, the difference in porosity between ×200 and ×4000 was not significant. Furthermore, when comparing the results with the HP-CH4-GA experiment, it was observed that an increase in Ra and Rq values positively influenced gas adsorption, while an increase in Rsk and Rku values had an unfavorable effect on gas adsorption. This suggests that surface roughness plays a crucial role in gas adsorption behavior. Overall, the findings highlight the significant influence of different methods on the evaluation of pore structure. The 3D algorithm and ×4000 magnification provide a more accurate description of the pore structure. Additionally, the variation in 3D surface roughness was found to be related to coal rank and had a notable effect on gas adsorption.

Formulation of fenofibrate nanocrystals with wet milling method

Background: Fenofibrate is an antihyperlipidemic belonging to BCS class II, practically insoluble in water and has high lipophilicity, so it is proven that the inhibitor of the rate of absorption of fenofibrate from the digestive tract is slow to dissolve. This study aims to increase the solubility of fenofibrate by forming nanocrystals.&#x0D; Method: Formation of nanocrystals using the wet milling method&#x0D; Result: The fenofibrate nanocrystals produced a particle size of 775.966 nm, a zeta potential of -21.302 mV, and a solubility of 5.977 μg/mL. &#x0D; Conclusion : The optimum formula with tween 80 components, grinding speed and grinding time in the manufacture of fenofibrate nanocrystals using the Factorial Design method obtained 0.2% tween 80, grinding speed of 500 rpm and grinding time of 1 hour. The critical parameter test results for the optimum formula obtained a particle size of 775.966 nm, a zeta potential of -21.302 mV and a solubility of 5.977 µg/mL. The DSC test showed that there was a difference in the melting point peaks and a decrease in crystal intensity between pure fenofibrate and fenofibrate nanocrystals. The FTIR test showed no difference in functional groups between pure fenofibrate and fenofibrate nanocrystals. The XRD test showed that there was a difference in peak crystal intensity between pure fenofibrate and fenofibrate nanocrystals. The SEM analysis shows that there are differences in shape and magnification used between pure fenofibrate and fenofibrate nanocrystals.

O-099 The inner cell mass (ICM) regions can be used to predict pregnancy with a similar accuracy as the original images of the entire embryo

Abstract Study question Can clinical pregnancy be accurately predicted using only ICM and TE regions in an embryo microscopy image? Summary answer The AI model accurately predicted pregnancy using ICM segmented images with a similar accuracy as using original embryo images. What is known already Previous research suggests that ICM and TE are key factors in determining embryo grade and clinical pregnancy. Grad-CAM images on the CNN models in various literature also highlight the significance of ICM and TE regions. However, there have been no studies to compare and assess the importance of the two regions in pregnancy prediction. This study aims to test the significance of each region by evaluating the performance of models after segmenting ICM and TE regions. Study design, size, duration We performed a retrospective study of single static images of 2,555 Day 5 blastocysts from seven in vitro fertilization (IVF) clinics between June 2011 and May 2022. The images were collected from standard optical light microscopes and matched with metadata such as pregnancy outcomes. ICM and TE regions were manually labeled and examined by 5 embryologists with over 10 years of experience. Participants/materials, setting, methods We defined a positive pregnancy indication as the presence of a gestational sac (G-SAC). We built 4 CNN models using original embryo images (“Original model”), ICM segmented images (“ICM model”), TE segmented images (“TE model”) and ICM &amp; TE segmented images (“ICM &amp; TE model”). The performances were measured through 3-fold cross validation. Main results and the role of chance In 3-fold cross validation, the mean and the standard deviation of AUROCs were 0.753±0.005 for Original model, 0.733±0.003 for ICM model, 0.724±0.016 for ICM &amp; TE model and 0.690±0.011 for TE model, respectively. The DeLong test showed significant differences between the AUCs of Original model and ICM model (p = 0.01), and ICM model and ICM &amp; TE model (p = 0.0003). Positive correlations were found between prediction values with pearson correlation [Confidence interval] for Original image and ICM model (0.426 [0.343, 0.495]), Original model and ICM &amp; TE model (0.345 [0.266, 0.419]) and Original model and TE model (0.223 [0.140, 0.304]). Original model showed the highest accuracy and TE model was the least accurate as expected. However, it is noteworthy that ICM model outperformed ICM &amp; TE model. Although it is well known that TE plays a significant role in implantation, forcing the model to utilize both ICM and TE to predict pregnancy could have muddled the analysis. This study proved that pregnancy can be successfully predicted using ICM regions only as well as original embryo images. Limitations, reasons for caution This study has limitations due to its retrospective nature, using embryo images from seven IVF centers. Further study with a larger dataset is warranted to offset the differences in focus, magnification and color of embryo images. Wider implications of the findings We showed that the AI model using ICM segmented images predicted pregnancy with a similarly high accuracy as using original embryo images. However, the model using TE segmented images showed the lowest performances. Utilizing well-focused ICM images may enhance the performance of pregnancy prediction models. Trial registration number not applicable

Calibration of magnification in two-dimensional low-dose full-body imaging for preoperative planning of total hip arthroplasty.

Preoperative planning of total hip arthroplasty (THA) using two-dimensional low-dose (2DLD) full-body imaging has gained popularity in recent years. The low-dose imaging system is said to produce a calibrated image with constant 1:1 magnification. However, the planning software used in conjunction with those images may introduce variations in the degree of magnification in 2DLD imaging, and this has not yet been investigated. The purpose of the present study was to quantify any variation in 2DLD image to assess the need for image calibration when using conventional planning software. Postoperative 2DLD images from 137 patients were retrospectively evaluated. Only patients who underwent THA for primary osteoarthritis were included in the study cohort. The femoral head diameter was measured by two independent observers using both Orthoview™ and TraumaCad™ planning software programs. Actual sizes of the femoral head implants were extracted from surgical reports to calculate image magnification. Magnification measurement reliability was calculated with the intra-class correlation coefficient (ICC) index. Image magnification varied among cases (mean 133%, range 129-135%). There was no statistical difference in mean image magnification among the various implant sizes (p = 0.8). Mean observer and inter-observer reliability was rated excellent. THA planning with 2DLD imaging is subject to variation in magnification as analyzed with conventional planning software in this series. This finding is of paramount importance for surgeons using 2DLD imaging in preparation for THA since errors in magnification could affect the accuracy of preoperative planning and ultimately the clinical outcome.

Pain Catastrophizing in Dance Students in Relation to Resilient Behavior and Self-Reported Injuries.

Pain catastrophizing is characterized by a set of negative emotional and cognitive processes in response to pain, with a tendency to focus inordinately on the painful sensation, exaggerate the damage, and perceive feelings of helplessness. It is a psychological factor that can be treated to help people more effectively cope with pain. In this cross-sectional study, we explored the relationship between self-reported injuries, resilient behavior, and pain catastrophizing in dance students, with more than 3 years of study in public conservatories or private academies. A sample of 147 dance students participated, 75.5% of whom were female with a mean age of 28.34 yrs (SD 11.42). Pain catastrophizing was assessed using the Pain Catastrophizing Scale, and resilience was assessed using the Resilience Scale. Students in the high resilience category reported lower scores on rumination and magnification, with a marginal difference in total catastrophizing and no difference in helplessness. Those who reported having suffered injuries during the last 3 years showed higher scores in total catastrophizing, rumination, and magnification, but not in helplessness. Those who reported mild injuries showed differences in pain catastrophizing, rumination, and magnification, while those with moderate and severe/very severe injuries only showed differences in magnification. The individual nature of pain perception and coping strategies suggests that pain catastrophizing may be considered before dance performance and in those dancers who do not recover as expected after injury.

Radial and Tangential Retinal Magnifications as Functions of Visual Field Angle Across Spherical, Oblate, and Prolate Retinal Profiles.

PurposeTo provide a tool for calculating radial and tangential retinal magnifications as functions of field angle and retinal shape and to articulate patterns of magnification across the retina for monocular and binocular combinations of prolate-, oblate-, and spherical-shaped retinas.MethodsFormulae were derived to calculate radial and tangential retinal magnifications (mm/deg) from field angle (degrees), retinal asphericity (unitless conic constant), retinal vertex radius of curvature (mm), and nodal point position (mm). Monocular retinal magnifications were determined for eyes with prolate, spherical, and oblate retinas as functions of field angle. Bilateral differences in magnifications were examined for combinations of those eyes.ResultsRetinal shape substantially affects magnification profiles even for eyes with the same axial length. Greatest magnification changes across a retina and between eyes, as well as greatest increase in radial–tangential differences (distortion), occur with prolate retinas. Binocular magnification differences were smallest for oblate retinas. Nodal points anterior to the vertex center of curvature and oblate asphericity both cause field-dependent reductions in magnification relative to the fovea (barrel distortion), whereas nodal points posterior to vertex center of curvature and prolate asphericity cause the opposite (pincushion distortion). Retinal magnification differences due to eye shape are much greater than aniseikonia thresholds and chromatic differences in magnification. A spreadsheet tool implements the magnification calculations.ConclusionsLocal retinal magnifications as functions of field angle have substantial effects on objective applications (imaging retinal anatomy) and subjective experiences (aniseikonia) and quantify an ocular property that differs across eye shapes and refractive errors.Translational RelevanceMethods are provided to customize the calculation of radial and tangential magnifications across the retina for individual eyes, which will bolster the multifactorial study of the effects of foveal and peripheral optics across eye shapes and refractive errors.

Size Constancy Mechanisms: Empirical Evidence from Touch.

Several studies have shown the presence of large anisotropies for tactile distance perception across several parts of the body. The tactile distance between two touches on the dorsum of the hand is perceived as larger when they are oriented mediolaterally (across the hand) than proximodistally (along the hand). This effect can be partially explained by the characteristics of primary somatosensory cortex representations. However, this phenomenon is significantly attenuated relative to differences in acuity and cortical magnification, suggesting a process of tactile size constancy. It is unknown whether the same kind of compensation also takes place when estimating the size of a continuous object. Here, we investigate whether the tactile anisotropy that typically emerges when participants have to estimate the distance between two touches is also present when a continuous object touches the skin and participants have to estimate its size. In separate blocks, participants judged which of two tactile distances or objects on the dorsum of their hand felt larger. One stimulation (first or second) was aligned with the proximodistal axis (along the hand) and the other with the mediolateral axis (across the hand). Results showed a clear anisotropy for distances between two distinct points, with across distances consistently perceived as larger than along distances, as in previous studies. Critically, however, this bias was significantly reduced or absent for judgments of the length of continuous objects. These results suggest that a tactile size constancy process is more effective when the tactile size of an object has to be approximated compared to when the distance between two touches has to be determined. The possible mechanism subserving these results is described and discussed. We suggest that a lateral inhibition mechanism, when an object touches the skin, provides information through the distribution of the inhibitory subfields of the RF about the shape of the tactile RF itself. Such a process allows an effective tactile size compensatory mechanism where a good match between the physical and perceptual dimensions of the object is achieved.

Linking individual differences in human primary visual cortex to contrast sensitivity around the visual field

A central question in neuroscience is how the organization of cortical maps relates to perception, for which human primary visual cortex (V1) is an ideal model system. V1 nonuniformly samples the retinal image, with greater cortical magnification (surface area per degree of visual field) at the fovea than periphery and at the horizontal than vertical meridian. Moreover, the size and cortical magnification of V1 varies greatly across individuals. Here, we used fMRI and psychophysics in the same observers to quantify individual differences in V1 cortical magnification and contrast sensitivity at the four polar angle meridians. Across observers, the overall size of V1 and localized cortical magnification positively correlated with contrast sensitivity. Moreover, greater cortical magnification and higher contrast sensitivity at the horizontal than the vertical meridian were strongly correlated. These data reveal a link between cortical anatomy and visual perception at the level of individual observer and stimulus location.

Prediction of ocular magnification and aniseikonia after cataract surgery.

Ocular magnification and aniseikonia after cataract surgery has been widely ignored in modern cataract surgery. The purpose of this study was to analyse ocular magnification and inter-individual differences in a normal cataract population with a focus on monovision. From a large dataset containing biometric measurements (IOLMaster 700) of both eyes of 9734 patients prior to cataract surgery, eyes were indexed randomly as primary (P) and secondary (S). Intraocular lens power (IOLP) was derived for the HofferQ, Haigis and Castrop formulae for emmetropia for P and emmetropia or myopia (-0.5 to -2 dpt) for S to simulate monovision. Based on the pseudophakic eye model in addition to these formulae, ocular magnification was extracted using matrix algebra (refraction and translation matrices and a system matrix describing the optical property of the entire spectacle corrected or uncorrected eye). With emmetropia for P and S the IOLP differences (S-P) showed a standard deviation of 0.162/0.156/0.157 dpt and ocular magnification differences yielded a standard deviation of 0.0414/0.0405/0.0408 mm/mrad for the HofferQ/Haigis/Castrop setting. Simulating monovision, the myopic eye (S) showed a systematically smaller mean absolute spectacle corrected ocular magnification than the emmetropic eye (-0.0351/-0.0340/-0.0336, respectively, relative magnification around 2%). If myopia in the S eye remains uncorrected, the reduction of ocular magnification is much smaller (around 0.2-0.3%). Vergence formulae for IOLP calculation sometimes implicitly define a pseudophakic eye model which can be directly used to predict ocular magnification after cataract surgery. Despite a strong similarity of both eyes, ocular magnification does not fully match between eyes and the prediction of ocular magnification and aniseikonia might be relevant to avoid eikonic problems in the pseudophakic eye.

Quantitative Analysis of Preoperative and Postoperative Photographs Posted on Social Media by Oculoplastic Surgeons.

To investigate and quantitatively analyze preoperative and postoperative photographs posted on social media by oculoplastic surgeons. Pre- and postoperative blepharoplasty photographs posted by oculoplastic surgeons on the social media platform Instagram were identified over a 4-month period. Photographs demonstrating a frontal pose of the periocular region were selected, and image analysis was performed to compare the preoperative and postoperative photographs. Quantitative image analysis was performed with a semiautomated script using ImageJ (v1.52k) software. Image analysis compared magnification, patient position, luminosity, relative color profiles, and edge detection/sharpness. Three oculoplastic surgeons graded these imaging metrics for the same photoset and the consensus grade was assigned to each category. Finally, the quantitative calculations were then compared with the consensus grades to develop receiver operating characteristic curves for further analysis. The study included 104 posts from 35 members of ASOPRS. Regarding patient positioning, 9 postings were 5%-10% offset from the patients' center, and 6 postings were more than 10% from the patients' center. The majority of photosets demonstrated less than or equal to 2.5% difference in magnification (69/104), with 7 postings demonstrating a greater than 5% difference, and 3 postings exhibiting greater than 10% difference in magnification. In the periocular region, 17.3% (18/104) of postings were found to have a greater than 10% difference in luminosity (>25.5 pixel-value). A more than 5% difference (>12.75 pixel-value) in pre- and postoperative edge-detection measurements was identified in 12 of 104 postings. In 22 of 104 photosets, the mean absolute deviation in color channel ratios was more than 0.01 and 15 of 104 photosets were found to have a mean absolute deviation more than 0.05. Numerous quantifiable photographic inconsistencies were identified in surgical photographs posted on social media by members of ASOPRS. Adoption of an automated image analysis tool that compares before-and-after surgical photographs could promote standardized oculoplastic surgery photography on social media.

Analysis of Multilayered Ground Amplification Characteristics by Scaled-Down Model Tests

During an earthquake, seismic waves travel through different media through the source to reach the surface. It is very necessary to study the dynamic characteristics of soil between different layers during earthquake. In order to explore the dynamic characteristics of soil under the action of ground seismic input motion, scaled-down model tests were carried out through 1 g shaking table tests based on a laminar shear box. After creating a dense lower ground with a sample of mixed silica and silty soil, and a loose upper ground with sand, the acceleration was measured by applying seismic loading through the 1 g shaking table test. Through the Peak ground acceleration, Spectral acceleration and Spectral acceleration amplification factors, the magnification variation and differences of each depth of the model and the dynamic characteristics of soil between different layers were displayed. In order to verify the reliability of the experimental data, a one-dimensional ground response analysis was carried out using DEEPSOIL software. The approximate results obtained by comparing each other can provide a basis for the accuracy of the experimental results.

Depth from axial differential perspective

We introduce an imaging-based passive on-axis technique for measuring the distance of individual objects in complex scenes. Two axially separated pupil positions acquire images (can be realized simultaneously or sequentially). Based on the difference in magnification for objects within the images, the distance to the objects can be inferred. The method avoids some of the disadvantages of passive triangulation sensors (e.g., correspondence, shadowing), is easy to implement and offers high lateral resolution. Due to the principle of operation it is especially suited for applications requiring only low to medium axial resolution. Theoretical findings, as well as follow-up experimental measurements, show obtainable resolutions in the range of few centimeters for distances of up to several meters.

P–132 Centralized versus local embryologists scoring of blastocyst quality obtained in a large European multicenter clinical trial

Abstract Study question Does blastocyst quality scoring by central assessment deviate from local assessment and potentially lead to the selection of a different single blastocyst for transfer? Summary answer Central and local assessment provided the same quality classification (poor / good / top) in 69% of all blastocysts and 63% of all transferred blastocysts. What is known already Blastocyst quality is scored most frequently by three morphological parameters, namely expansion and hatching (EH) status, inner cell mass (ICM) grading and trophectoderm (TE) grading. The score is used to define the quality classification (poor / good / top) which determines which embryo is to be transferred or cryopreserved. Blastocyst scoring and grading can be highly subjective, which does influence the choice for transfer and cryopreservation. Time-lapse imaging technology captures additional input about embryo development as well as enables centralized data storage and sharing for independent central assessments. Study design, size, duration Pooled embryo analysis from a prospective, randomized, multicenter trial (RAINBOW) of 619 women undergoing ovarian stimulation with an individualized dose of follitropin delta in a long GnRH agonist protocol between May 2018 and January 2020. Blastocysts were centrally assessed using time-lapse images by two independent assessors and one adjudicator . Selection of the blastocyst for transfer by local assessment was based on morphological scoring and not on morphokinetic time-lapse parameters. Participants/materials, setting, methods Oocytes were fertilized by ICSI and cultured in the Embryoscopeâ (Vitrolife) up to day 5 for transfer or day 5/6 for cryopreservation. Embryos were assessed as either non-blastocyst or blastocyst. Blastocysts were graded centrally and locally at 116 hrs of development, based on EH status (1–6), ICM (A-D) and TE grading (A-D). Central assessors were blinded to local assessment and embryo transfer selection. Main results and the role of chance In total 4282 embryos were assessed centrally, of which 2046 day 5 embryos (48%) were adjudicated due to a scoring difference of at least one parameter between the two central assessors. In total 38% of day 5 embryos were judged as non-blastocysts and 62% as blastocysts of which 61% (i.e. 38% of all embryos) were determined to be of good or top quality. Identical results in terms of quality classification (poor / good / top) were obtained for 69% of blastocysts between local and central assessment and in 78%, between the two central assessors. Moreover, central and local scoring were identical in 62% for EH status, 53% for ICM grading and 57% for TE grading. For all transferred blastocysts (n = 508), central and local quality assessment was aligned for 63%. The ongoing pregnancy rate following single blastocyst transfer (SBT) was 41% (202/489), and similar to when considering only the transfers for which the central assessment had the same or a higher classification than the local assessment (166/411=40%). In 16% of all SBT, central quality assessment gave a lower score for the transferred blastocyst than the central assessment. This discrepancy could potentially have led to transfer of a different blastocyst. Limitations, reasons for caution This trial included assessments made by embryologists from 20 IVF centres. Some centres has limited experience with time-lapse technology for morphological blastocyst scoring. Scoring could therefore have been affected by differences in focal planes, magnification and contrast compared to inverted microscopy, with potential influence on blastocyst scores and quality classification. Wider implications of the findings: Local and central blastocyst quality classification based on morphology aligns well but remains subjective. Embryo assessment may benefit from using tools like artificial intelligence-based algorithms for a more objective analysis. Trial registration number NCT03564509

Effect of Aniseikonia Induced by a Size Lens on Contrast Visual Acuity and Stereo Acuity and Eye-hand Coordination

Purpose : The purpose of this study is to find out the effect of unequal vision induced by a size lens on contrast visual acuity, and distance and near stereo acuity.Methods : Thirty people in their 20s and 30s were involved to measure for high and low contrast visual acuity, distance stereo acuity and near stereo acuity according to the magnification of 2, 4, and 6% of the size lens. Contrast visual acuity composed of a Randolt ring was measured using LogMAR visual acuity, and it was divided into high contrast (100%) and low contrast (25, 10%) visual acuity according to the contrast of the target. The distance stereo acuity was measured using a three-rod test, and the near stereo acuity was measured using a random dot test. For eyehand coordination, a device made with a t-wall as a motif was used.Results : Contrast visual acuity did not show any significant difference after 2% aniseikonia induction, but showed a significant difference and a decrease at 4 and 6% aniseikonia induction (p<0.050). Contrast visual-acuity decreased significantly as the degree of aniseikonia increased, and as the degree of contrast decreased. The distance and near stereo-acuity showed a significant difference and decreased when the aniseikonia of 4 and 6% was induced, except for the aniseikonia of 2% (p<0.050). Eye-hand coordination decreased significantly with increasing aniseikonia (p<0.050).Conclusion : It was identified that as the aniseikonia increased, contrast visual-acuity, stereo-acuity and the capability of eye-hand coordination were decreased. In clinical practice, aniseikonia should be considered when an optician prescribes aniseikonia. However, if the prescription is avoided in consideration of aesthetics, the difference in magnification must be induced to within 2%. Therefore, it is expected that it will contribute to improving the health and quality of life by preventing the factors deteriorating daily life that can be caused by aniseikonia.