Aberrant Values Research Articles

Refractive and visual outcomes of two different aspheric monofocal intraocular lenses with differing tinting and spherical aberration values

Purpose: To compare refractive and visual outcomes of two diffractive monofocal intraocular lenses (IOLs) with different tinting and spherical aberration values. Study design: Retrospective case series. Methods: The right eye of consecutive patients who had undergone bilateral implantation of SZ-1 (NIDEK Co. Ltd., Gamagori, Japan) or ZCB00 (Johnson and Johnson Inc. New Brunswick, NJ, USA) IOLs was evaluated. Refractive outcomes, changes in visual acuity, ocular spherical aberration, and changes in photopic and mesopic contrast sensitivity were analyzed. Results: Thirty-three eyes received the SZ-1 IOL (SZ-1 group, while 29 eyes received the ZCB00 IOL (ZCB00 group). The mean preoperative manifest refraction spherical equivalent (MRSE) was −1.48 ± 4.74 D and −0.34 ± 1.50 in the SZ-1 group and ZCB00 group, respectively. At 3 months, the mean MRSE was −0.87 ± 1.08 D and −0.65 ± 0.76, respectively (p=0.25). At 3 months postoperatively, the mean best spectacle-corrected visual acuity was 0.14 ± 0.20 LogMAR and 0.11 ± 0.17 LogMAR, respectively (p=0.67). At the same time point, ocular spherical aberration was statistically significantly different (0.01 ± 0.23 μm vs. −0.51 ± 0.51 μm, respectively; p<0.0001). Postoperatively, the mean photopic and scotopic contrast sensitivity did not differ between the groups (p=0.57). Conclusion: Postoperative refractive outcomes and visual acuity following the implantation of these aspheric IOLs were similar. The different asphericity and yellow tinting of the SZ-1 IOL did not affect postoperative visual performance.

Suitability of calibrated X-ray fluorescence core scanning for environmental geochemical characterisation of heterogeneous sediment cores

Multi-element analysis of discrete samples via X-Ray fluorescence or inductively coupled plasma spectrometry is commonly used to characterise the composition of solid geo-materials for environmental geochemical characterisation. Conventional geochemical analysis of individual samples is time consuming and costly, which often results in low-resolution sampling with the danger of missing crucial information. X-ray fluorescence Core Scanning (XCS) provides an alternative method to obtain elemental information, which can be potentially used quantitatively when combined with the Multivariate Log-ratio Calibration (MLC) approach. The suitability of the XCS-MLC method was tested for environmental geochemical characterisation on four terrestrial Holocene-Pleistocene sediment cores that have a variable lithology (clay, sand, peat, with variable calcareous content), were stored at ambient room conditions and scanned post sampling. Element contents based on XCS-MLC and conventional geochemical analysis proved to be comparable (R2 > 0.5) for Al, Ca, Cr, Fe, K, Sr, Mn, Ni, Pb, Rb, S, Si, Ti, Zn, Zr, and also for Br as proxy for organic matter. For As, Cu and Ba the correlations were less satisfactory (R2 < 0.4) partially due to the low concentration ranges present in these sediments. For some samples aberrant high values for Ca, Fe, S, and Zn were introduced by application of the MLC method due to extrapolation outside the MLC-calibrated range. Similar to the conventional element analyses the XCS-MLC approach has the ability to retrieve quantitative element contents and enable the calculation of mineral phases such as calcium carbonate and reactive iron species. Both conventional and XCS-MLC methods reproduced the average contents per sediment layer and mostly their ranges. Nevertheless, local features such as diagenetic enrichments were not always evident from the discrete samples. Thus, a better understanding of the spatial heterogeneity in geochemical and mineralogical contents within the sediment layers was obtained with the additional XCS-MLC data. Our study shows that also cores stored under unfavourable conditions can be reliably re-analysed with XCS to generate high resolution records.

Evaluation of spontaneous regional brain activity in weight-recovered anorexia nervosa

Whereas research using structural magnetic resonance imaging (sMRI) reports sizable grey matter reductions in patients suffering from acute anorexia nervosa (AN) to be largely reversible already after short-term weight gain, many task-based and resting-state functional connectivity (RSFC) studies suggest persistent brain alterations even after long-term weight rehabilitation. First investigations into spontaneous regional brain activity using voxel-wise resting-state measures found widespread abnormalities in acute AN, but no studies have compared intrinsic brain activity properties in weight-recovered individuals with a history of AN (recAN) with healthy controls (HCs). SMRI and RSFC data were analysed from a sample of 130 female volunteers: 65 recAN and 65 pairwise age-matched HC. Cortical grey matter thickness was assessed using FreeSurfer software. Fractional amplitude of low-frequency fluctuations (fALFFs), mean-square successive difference (MSSD), regional homogeneity (ReHo), voxel-mirrored homotopic connectivity (VHMC), and degree centrality (DC) were calculated. SMRI and RSFC data were analysed from a sample of 130 female volunteers: 65 recAN and 65 pairwise age-matched HCs. Cortical grey matter thickness was assessed using FreeSurfer software. Fractional amplitude of low-frequency fluctuations (fALFF), mean-square successive difference (MSSD), regional homogeneity (ReHo), voxel-mirrored homotopic connectivity (VHMC), and degree centrality (DC) were calculated. Abnormal regional homogeneity found in acute AN seems to normalize in recAN, supporting assumptions of a state rather than a trait marker. Aberrant fALFF values in the cerebellum and the infertior temporal gyrus could possibly hint towards trait factors or a scar (the latter, e.g., from prolonged periods of undernutrition), warranting further longitudinal research.

Breadth-first piston diagnosing approach for segmented mirrors through supervised learning of multiple-wavelength images.

Piston diagnosing approaches for segmented mirrors via machine-learning have shown great success. However, they are inevitably challenged with 2π ambiguity, and the accuracy is usually influenced by the location and number of submirrors. A piston diagnosing approach for segmented mirrors, which employs the breadth-first search (BFS) algorithm and supervised learning strategies of multi-wavelength images, is investigated. An original kind of object-independent and normalized dataset is generated by the in-focal and defocused images at different wavelengths. Additionally, the segmented mirrors are divided into several sub-models of binary tree and are traversed through the BFS algorithm. Furthermore, two deep image-based convolutional neural networks are constructed for predicting the ranges and values of piston aberrations. Finally, simulations are performed, and the accuracy is independent of the location and number of submirrors. The Pearson correlation coefficients for test sets are above 0.99, and the average root mean square error of segmented mirrors is approximately 0.01λ. This technique allows the piston error between segmented mirrors to be measured without 2π ambiguity. Moreover, it can be used for data collected by a real setup. Furthermore, it can be applied to segmented mirrors with different numbers of submirrors based on the sub-model of a binary tree.

Using Deep Learning to Extrapolate Protein Expression Measurements.

Mass spectrometry (MS)‐based quantitative proteomics experiments typically assay a subset of up to 60% of the ≈20 000 human protein coding genes. Computational methods for imputing the missing values using RNA expression data usually allow only for imputations of proteins measured in at least some of the samples. In silico methods for comprehensively estimating abundances across all proteins are still missing.Here, a novel method is proposed using deep learning to extrapolate the observed protein expression values in label‐free MS experiments to all proteins, leveraging gene functional annotations and RNA measurements as key predictive attributes. This method is tested on four datasets, including human cell lines and human and mouse tissues. This method predicts the protein expression values with average R2 scores between 0.46 and 0.54, which is significantly better than predictions based on correlations using the RNA expression data alone. Moreover, it is demonstrated that the derived models can be “transferred” across experiments and species. For instance, the model derived from human tissues gave a R2=0.51 when applied to mouse tissue data. It is concluded that protein abundances generated in label‐free MS experiments can be computationally predicted using functional annotated attributes and can be used to highlight aberrant protein abundance values.

Visualization of spherical aberration using an optically levitated droplet as a light source.

Optical aberrations can greatly distort the image created by an optical element. Several aberrations can affect the image simultaneously and discerning or visualizing specific aberrations can be difficult. By making use of an optically levitated droplet as a light source, we have visualized the spherical aberration and coma of a lens. The droplet approximates a point source in the ray optic regime but, at the same time, creates a diffraction pattern in the far-field region similar to that used in the Ronchi test. When focused by a lens, this micro double point source creates patterns that resemble comets, barreling, hyperbolic triangles, and, most strikingly, a spider. We show how all these patterns are a consequence of spherical aberration and coma. The Zernike polynomials were used to quantify the value of several individual aberrations by comparing them to patterns resulting from numerical simulations.

Calculation of the wave aberration of field curvature and color aberrations of an ultrawide-angle optical system

Based on the aberration theory of plane-symmetric optical system, this paper develops a method for calculating the wave aberration of the field curvature and color aberrations of each optical surface in an ultrawide-angle optical system, which enables us to analyze, like Seidel aberration theory, the contribution and balance of these aberrations between different optical surfaces. We then apply the resultant formulas to calculate the wave aberrations of the field curvature and color aberrations of two optical lenses, and compare the results with the corresponding wave aberrations values obtained from Seidel aberration theory and Zemax software. The study shows that accuracy of the results obtained with our formulas are quite satisfactory even in the large range of field view while the accuracy of those with the Seidel aberrations is limited by the field angle. Our method can provide an effective means for aberration analysis and optimization design of an ultrawide-angle optical systems.

Optical Performance of a Monofocal Intraocular Lens Designed to Extend Depth of Focus.

To test the performance of a new monofocal intraocular lens, intended to extend depth of focus (Tecnis Eyhance, ICB00; Johnson & Johnson Vision, Inc) (ICB-IOL), in comparison to a standard monofocal IOL (Tecnis 1-piece, ZCB00; Johnson & Johnson Vision, Inc) (ZCB-IOL) of the same platform and material. Assessment of the optical performance of the two IOLs was made in vitro using an optical test bench with a model eye. The spherical aberration, modulation transfer function (MTF), and area under the MTF (MTFa) were obtained for pupil sizes ranging from 2 to 5 mm. Through-focus MTFa curves between -3.00 and +1.00 diopters (D) were obtained with three pupil sizes (2, 3, and 4.5 mm). Halo formation was also assessed for both lenses. The ICB-IOL had slightly worse optical quality at its best focus (ie, lower MTF scores at distance vision) and more negative spherical aberration than the ZCB-IOL for pupils ranging from 2 to 3 mm. The maximum of the through-focus MTFa curve of the ICB-IOL with a 2-mm pupil shifted to a myopic defocus of -0.50 D. For larger pupils (≥ 3.5 mm), there were no differences in spherical aberration, MTF scores, and halo energy between the two lenses. The new ICB-IOL is a modified monofocal lens with 0.50 D of additional power in its central 2-mm zone and more negative spherical aberration values, which induce a myopic shift of the maximum of optical quality and could improve intermediate vision. For pupils larger than 3.5 mm, there were no differences between IOLs. The new ICB-IOL design would produce photic phenomena comparable to a standard IOL. [J Refract Surg. 2020;36(9):625-632.].

Pentacam corneal densitometry-guided treatment of adenoviral corneal subepithelial infiltrates: a comparative study between transepithelial phototherapeutic keratectomy and topical tacrolimus

To compare the changes in the measurement of corneal densitometry and total corneal higher-order aberrations (HOAs) between topical tacrolimus and transepithelial phototherapeutic keratectomy (Te-PTK) in the treatment of adenoviral corneal subepithelial infiltrates (SEIs). This is an interventional prospective randomized study, including 63 eyes of 35 patients with symptomatic adenoviral corneal SEIs for at least 6months. All patients underwent previous topical steroid therapy associated with unsatisfactory response and/or complications. Patients were assigned into three groups: (1) Te-PTK group: Te-PTK with MMC 0.02% was performed by a Technolas; Teneo excimer laser; (2) tacrolimus group: tacrolimus 0.03% ointment was applied once daily for 2-6months; the endpoint of treatment was based on the improvement in the corneal densitometry, BCVA, and OSDI; and (3) control group: no intervention was done. BCVA, corneal densitometry, and total corneal higher-order aberrations (HOAs) evaluation using Pentacam HR were done at the baseline, 1week, and then 1, 3, 6, and 12months of the study. The study population was similar between all groups. The mean follow-up was 12.75 ± 0.9months. Bilateral corneal SEI was recorded at 80%. At 12-month follow-ups, the mean BCVA improved in both the Te-PTK and tacrolimus groups without significant changes in the control group. The mean corneal densitometry of the anterior, central, and total cornea decreased significantly in the Te-PTK and tacrolimus groups. HO-RMS and total RMS decreased significantly in the Te-PTK and tacrolimus groups. BCVA, corneal densitometry (anterior, central, and total cornea), and corneal aberrations (total coma, total trefoil, HO-RMS, and total RMS) values were significantly better for the Te-PTK and tacrolimus groups than the control group. There were no statistically significant differences between Te-PTK and tacrolimus groups in terms of BCVA, corneal densitometry, corneal HOA, and the persistence of corneal SEIs. The persistence of corneal SEIs was significantly lower in Te-PTK and tacrolimus groups than the control group. Te-PTK and topical tacrolimus are effective methods for the treatment of adenoviral corneal SEIs improving visual acuity, corneal densitometry, and corneal HOA. The densitometry program of the Pentacam may give an objective guide for the treatment of adenoviral corneal SEIs. ClinicalTrials.gov ID is NCT04267991.

Comprehensive Genomic Analysis of Translocation Renal Cell Carcinoma Reveals Copy-Number Variations as Drivers of Disease Progression.

Translocation renal cell carcinoma (tRCC) is a rare, aggressive renal cell carcinoma (RCC) subtype. There is currently limited understanding on the role of molecular alterations in the pathogenesis and progression of these tumors. We investigated the association between somatic alterations and clinical outcomes in two independent cohorts profiled using DNA sequencing. Twenty-two tRCCs underwent targeted sequencing [Memorial Sloan Kettering Cancer Center (MSK)-IMPACT]; a subset was profiled using exome-sequencing and combined with exome data from The Cancer Genome Atlas (TCGA) for analysis. The prognostic value of specific somatic aberrations, tumor mutation burden (TMB), and fraction of copy-number-altered genome (FCNAg) was explored. In TCGA cases, neoantigen prediction and immune cell deconvolution were performed using RNA-sequencing and exome data. Overall survival estimates were computed using the Kaplan-Meier method; time-on-treatment was calculated for 14 MSK-IMPACT patients who underwent systemic therapy. Associations between molecular features and outcomes were evaluated using nonparametric testing. Copy-number aberrant tRCCs were associated with poor overall survival (P = 0.03). Pediatric patients had tumors with lower FCNAg (P = 0.01). In one adult case with two chronologically distinct tumor samples sequenced, we confirmed that copy-number events occurred early during evolution. TERT promoter mutations were found exclusively in high-stage tumors. We found that tRCCs displayed distinct angiogenesis and PD-L1 gene expression profiles compared with other RCC subtypes. Tumors molecularly defined by increased copy-number variations were associated with aggressive disease in tRCC. A higher burden of genomic events in adults compared with pediatric cases likely reflects a more aggressive clinical course. The unique immunophenotypic characteristics of tRCC merit further exploration.

Experimental Investigation of Color Reproduction Quality of Color 3D Printing Based on Colored Layer Features.

Color three-dimensional (3D) printing is an advanced 3D printing technique for reproducing colorful 3D objects, but it still has color accuracy issues. Plastic-based color 3D printing is a common color 3D printing process, and most factors affecting its color reproduction quality have been studied from printing materials to parameters in the fixed consecutive layers. In this work, and combined with variable stair thickness, the colored layer sequence in sliced layers of a specific 3D color test chart is deliberately changed to test the effects of colored layer features on its final color reproduction quality. Meanwhile, the colorimetric measurement and image acquisition of printed 3D color test charts are both achieved under standard conditions. Results clearly show that the chromatic aberration values and mean structural similarity (MSSIM) values of color samples have a significant correlation with the colored stair thickness, but both did not display a linear relationship. The correlation trends between colored layer sequence and the above two indexes are more localized to the colored stair thickness. Combined with color structural similarity (SSIM) maps analysis, a comprehensive discussion between colored layer features and color reproduction quality of color 3D printing is presented, providing key insights for developing further accurate numerical models.

Variations in Values of State, Response Entropy and Haemodynamic Parameters Associated with Development of Different Epileptiform Patterns during Volatile Induction of General Anaesthesia with Two Different Anaesthetic Regimens Using Sevoflurane in Comparison with Intravenous Induct: A Comparative Study.

Background and Objectives: Raw electroencephalographic (EEG) signals are rarely used to monitor the depth of volatile induction of general anaesthesia (VIGA) with sevoflurane, even though EEG-based indices may show aberrant values. We aimed to identify whether response (RE) and state entropy (SE) variations reliably reflect the actual depth of general anaesthesia in the presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anaesthesia. Materials and Methods: A randomized, prospective clinical study was performed with 60 patients receiving VIGA using sevoflurane with the increasing concentrations (group VIMA) or the vital capacity (group VCRII) technique or an intravenous single dose of propofol (group PROP). Facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, RE and SE, and standard electroencephalographic evaluations were performed in these patients. Results: In contrast to periodic epileptiform discharges, erroneous SE and RE values in the patients’ EEGs were associated with the presence of polyspikes (PS) and rhythmic polyspikes (PSR), which were more likely to indicate toxic depth rather than false emergence from anaesthesia with no changes in the FiAA, FeAA, and MAC of sevoflurane. Conclusion: Calculated RE and SE values may be misleading during VIGA when EPs are present in patients’ EEGs. During VIGA with sevoflurane, we recommend monitoring raw EEG data in scientific studies to correlate it with potentially erroneous RE and SE values and the end-tidal concentration of sevoflurane in everyday clinical practice, when monitoring raw EEG is not available, because they can mislead anaesthesiologists to reduce sevoflurane levels in the ventilation gas and result in unintentional true emergence from anaesthesia. Further studies are required to investigate the behaviour of EEG-based indices during rapid changes in sevoflurane concentrations at different stages of VIGA and the influence of polyspikes and rhythmic polyspikes on the transformation of EEG signals into a digital form.

Do Organisational Circumstances in the Birth Ward Influence Perinatal Outcome? A Retrospective Analysis of Over 43.000 Deliveries

Background: Birth can be a high-risk situation requiring identification of potential complications and decisive action. Identifying times of increased risk with respect to working patterns is important to optimise quality and safety. The umbilical cord pH and the 1-minute APGAR score are evaluated predictive parameters for the neonatal outcome. Aberrant values may be related to many factors, including special circumstances during birth. Objectives: In this study, we checked the data of our hospital to find out, whether the day, the time of birth, as well as the Hand Over Times (HOT), may be correlated to conspicuous findings. Methods: This retrospective cohort study included deliveries of 20 years. The impaired fetal outcome was defined as pH values 6. Conclusion: These results demonstrate a high standard of care during the different days, times, and HOT over the last decades despite an increased workload. As the neonatal outcome depends on various factors, further studies are necessary to improve the working environment

Normative database of spatiotemporal gait parameters using inertial sensors in typically developing children and young adults

BackgroundInertial sensors are increasingly useful to clinicians and researchers to detect gait deficits. Reference values are necessary for comparison to children with gait abnormalities. ObjectiveTo present a normative database of spatiotemporal gait and turning parameters in 164 typically developing children and young adults ages 5−30 utilizing the APDM Mobility Lab® system. MethodsParticipants completed the i-WALK test at both self-selected (SS) and fast as possible (FAP) walking speeds. Spatiotemporal gait and turning parameters included stride length, stride length variability, gait speed, cadence, stance, swing, and double support times, and foot strike, toe-off, and toe-out angles, turn duration, peak turn velocity and number of steps to turn. ResultsAbsolute stride length and gait speed increased with age. Normalized gait speed, absolute and normalized cadence, and stride length variability decreased with age. Normalized stride length and all parameters of gait cycle phase and foot position remained unaffected by age except for greater FSA in children 7−8. Foot position parameters in children 5−6 were excluded due to aberrant values and high standard deviations. Turns were faster in children ages 5–13 and 7–13 in the SS and FAP conditions, respectively. There were no differences in number of steps to turn. Similar trends were observed in the FAP condition except: normalized gait speed did not demonstrate a relationship with age and children ages 5–8 demonstrated increased stance and double support times and decreased swing time compared to children 11−13 and young adults (ages 5−6 only). Females ages 5−6 demonstrated increased stride length variability in the SS condition; males ages 7−8 and 14–30 ha d increased absolute stride length in the FAP condition. Similarities and differences were found between our values and previous literature. SignificanceThis normative database can be used by clinicians and researchers to compare abnormal gait patterns and responses to interventions.

Usefulness of real time elastography strain ratio in the assessment of cervical intraepithelial neoplasia and cervical cancer using a reference material

To assess the usefulness of real time elastography (RTE) strain ratio (SR) in diagnosing cervical cancer (CC) and cervical intraepithelial neoplasia (CIN), using a synthetic experimental device (ED) as reference material. Seventy-nine participants were enrolled, divided in three groups: Group 1 - benign cervix (n=39); Group 2 - CIN (n=32); Group 3 - CC (n=8). Transvaginal RTE was performed, with SR determination, as the ratio between the ED and the cervical tissue. Mean SR values of the groups were compared; diagnostic performance was assessed by tracing the receiver operating characteristic (ROC) curve. Area under the curve (AUC) was analyzed. Cut-off values were established. Pathological results were considered as reference for data interpretation. SR means significantly differed in Group 1 as compared to Groups 2 and 3 (p=0.001). Excluding 2 aberrant values in Group 3, assigned to cases complicated by hemorrhagic necrosis, statistical difference was also noted between Groups 2 and 3 (p=0.02). For Groups 1 and 3, AUC was 0.966 with a 95%CI (0.914-1.000); the cut-off point of SR was 1.42, with a sensitivity of 100% and a specificity of 94.9%. AUC was 0.752 with a 95%CI (0.629-0.876) for Groups 1 and 2. For the cut-off value of 1.03, sensitivity and specificity were 75% and 74%, respectively. RTE SR, performed with a synthetic reference material, seems a reliable method for distinguishing between benign uterine cervix and malignancy, with promising results as a complementary investigation in diagnosing CIN. However, SR becomes inoperant in cases of cancer complicated with hemorrhagic necrosis.

Evaluating missing value imputation methods for food composition databases

Missing data are a common problem in most research fields and introduce an element of ambiguity into data analysis. They can arise due to different reasons: mishandling of samples, measurement error, deleted aberrant value or simply lack of analysis. The nutrition domain is no exception to the problem of missing data. This paper addresses the problem of missing data in food composition databases (FCDBs). Missing data in FCDBs results in incomplete FCDBs, which have limited usage, because any dietary assessment can be performed only on a complete dataset. Most often, this problem is resolved by calculating means/medians from excising data in the same database or borrowing data from other FCDBs. These solutions introduce significant error. We focus on missing data imputation techniques based on methods for substituting missing values with statistical prediction: Non-Negative Matrix Factorization (NMF), Multiple Imputations by Chained Equations (MICE), Nonparametric Missing Value Imputation using Random Forest (MissForest), and K-Nearest Neighbors (KNN), and compared them with commonly used approaches - fill-in with mean, fill-in with median. The data used was from national FCDBs collected by EuroFIR (European Food Information Resource Network). The results show that the state-of-the-art methods for imputation yield better results than the traditional approaches.

Comparison of wavefront aberrations in eyes with multifocal and monofocal iols before and after Nd:YAG laser capsulotomy for posterior capsule opacification.

The aim of this study was to compare wavefront aberrations before and after Nd:YAG capsulotomy in multifocal intraocular lens (MfIOL) and monofocal (MoIOL) pseudophakic eyes with posterior capsule opacification (PCO). Wavefront aberrations were measured using a ARK-10000 topographer before and after Nd:YAG capsulotomy in eyes that underwent MfIOL or MoIOL implantation and developed PCO. Total and higher-order aberrations (HOAs) values were evaluated as root mean square (RMS). The study included 64 eyes with MfIOLs (64 patients) and 72 with MoIOLs (72 patients) that developed PCO. Total RMS values before and 1month after Nd:YAG capsulotomy were 0.863 ± 0.27 and 0.504 ± 0.24 in the MFIOL group and 0.862 ± 0.31 and 0.466 ± 0.26 in the MoIOL group, respectively. Total RMS values did not differ significantly between the groups before (p = 0.914) or 1month after Nd:YAG laser capsulotomy (p = 0.357), but decreased significantly after Nd:YAG capsulotomy compared to baseline in both the MfIOL (p = 0.027) and MoIOL (p = 0.012) groups. HOA values before and 1month after Nd:YAG capsulotomy were 0.546 ± 0.23 and 0.364 ± 0.19 in the MfIOL group and 0.500 ± 0.21 and 0.346 ± 0.18 in the MoIOL group, respectively. HOA values did not differ significantly before (p = 0.828) or after Nd:YAG capsulotomy (p = 0.111), while both groups showed significant reduction in HOAs after Nd:YAG capsulotomy (MfIOL: p = 0.021, MoIOL: p = 0.027). Nd:YAG capsulotomy reduces total and HOAs to the same extent in eyes with both MfIOLs and MoIOLs, with no significant impact of the IOL design.

Utilization of a convolutional method for Alzheimer disease diagnosis

With the increasing number of cases as well as care costs, Alzheimer’s disease has gained more interest in several scientific communities especially medical and computer science. Clinical and analytical tests are widely accepted techniques for detecting Alzheimer cases. However, early detection can help prevent damage to brain tissue and heal it with proper treatment. Interpreting brain images is considered as a time-consuming task with a high error-prone. Recently, advanced machine learning methods have successfully proved high performance in various fields including brain image analysis. These existing techniques, which become more used for clinical disease detection, present challenging wrongness sensibility to detect aberrant values or areas in the human brain. We conducted our work to automate the detection of the damaged areas and diagnose Alzheimer’s disease. Our method can segment MRI images, identify brain lesions and the different stages of Alzheimer’s disease. We evaluated our method using ample cases form public databases to demonstrate that our proposition performed reliable and effective results. Our proposal achieved an accuracy of 94.73%, a recall rate of 93.82%, and an F1-score of 92.8%. Also, the detection precision reached 91.76% with a sensitivity of 92.48% and a specificity rate of 90.64%. Our method creates an important way to optimize the imaging process via an automated computer-assisted diagnosis using potential deep learning methods to increase the consistency and accuracy of Alzheimer’s disease diagnosis worldwide.

Comparison of Two Different Accelerated Corneal Cross-linking Procedure Outcomes in Patients with Keratoconus

Background:Corneal cross-linking treatment is the unique treatment method that can cease the progression of keratoconus disease. Because of the long duration of conventional treatment, accelerated cross-linking treatment methods are being developed.Aims:To compare two different accelerated corneal cross-linking protocols in terms of postoperative visual acuity and topographic findings (higher-order aberrations and keratometry values).Study Design:Retrospective comparative study.Methods:Sixty-five eyes of 43 patients (30 men and 13 women) who underwent two different accelerated corneal cross-linking protocols (10 min, 9 mW/cm2 and 5 min, 18 mW/cm2) for progressive keratoconus were retrospectively analyzed. Patients were divided into two groups according to the accelerated corneal cross-linking treatment protocol: group 1 (10 min, 9 mW/cm2, 32 eyes of 21 patients) and group 2 (5 min, 18 mW/cm2, 33 eyes of 22 patients). Uncorrected visual acuity and best-corrected visual acuity values and topographic findings (central corneal thickness and flat and steep keratometry values) were recorded preoperatively and 6 months after corneal cross-linking treatment. High-order aberration values measured with Pentacam preoperatively and 6 months after corneal cross-linking were also recorded.Results:In both groups, a significant improvement was detected in the uncorrected visual acuity and best-corrected visual acuity levels preoperatively and 6 months postoperatively (group 1: p=0.001, p=0.001 and group 2: p=0.001, p=0.001, respectively). In addition, central corneal thickness values decreased significantly in both groups (p=0.006 and 0.001). Trefoil values showed no significant difference preoperatively and 6 months postoperatively in group 1 (p=0.160 and 0.620, respectively). In groups 1 and 2, coma values were found to decrease significantly in the 6th postoperative month compared with preoperative values (p=0.001 and 0.020, respectively). There was no significant difference between preoperative and 6th month postoperative horizontal and vertical trefoil values in both groups (p=0.850 and 0.140, respectively). There was no significant difference between the two groups in terms of preoperative and 6th month postoperative higher-order aberrations, refractive errors, keratometry values, and uncorrected visual acuity and best-corrected visual acuity levels.Conclusion:Both accelerated corneal cross-linking procedures provide similar improvement in topographic findings, coma values and visual acuity.

Spherical Aberration Customization to Extend the Depth of Focus With a Clinical Adaptive Optics Visual Simulator.

To evaluate the use of the VAO adaptive optics visual simulator (Voptica SL, Murcia, Spain) for customization of spherical aberration to increase depth of focus. Through-focus visual acuity with both high- and low-contrast letters from +1.00 to -3.00 diopters (D) was measured in 17 dilated eyes with three different induced amounts of spherical aberration for a 4.5-mm pupil diameter: control (0 µm), -0.15 µm, and -0.30 µm. The defocus curves followed the same behavior with both values of contrast, but the visual acuity was 0.2 logMAR lower with low contrast. The mean values of high-contrast logMAR visual acuity at far, intermediate (67 cm), and near (40 cm) were -0.10, 0.11, and 0.37 for control, 0.04, 0.00, and 0.15 for -0.15 µm, and 0.23, 0.00, and 0.06 for -0.30 µm conditions. The 95% confidence interval ranged from ±0.14 to ±0.45 logMAR and the middle 50% of the distribution was approximately 0.2 logMAR. Negative values of spherical aberration extend the depth of focus in different ways depending on each patient. The VAO is a new instrument that allows the visual customization of spherical aberration to enhance depth of focus. [J Refract Surg. 2020;36(4):223-229.].