Segment Parameters Research Articles

Texture analysis of contrast enhancement CT in the differential diagnosis of tumor and tumor-like cystic lesions of the pancreas: possibilities in texture preprocessing and various segmentation parameters

Texture analysis of contrast enhancement CT in the differential diagnosis of tumor and tumor-like cystic lesions of the pancreas: possibilities in texture preprocessing and various segmentation parameters

Accuracy of intraocular lens calculation formulas based on swept-source OCT biometer in cataract patients with phakic intraocular lens

PurposeTo research the accuracy of intraocular lens (IOL) calculation formulas and investigate the effect of anterior chamber depth (ACD) and lens thickness (LT) measured by swept-source optical coherence tomography biometer (IOLMaster 700) in patients with posterior chamber phakic IOL (PC-pIOL).MethodsRetrospective case series. The IOLMaster 700 biometer was used to measure axial length (AL) and anterior segment parameters. The traditional formulas (SRK/T, Holladay 1 and Haigis) with or without Wang-Koch (WK) AL adjustment, and new-generation formulas (Barret Universal II [BUII], Emmetropia Verifying Optical [EVO] v2.0, Kane, Pearl-DGS) were utilized in IOL power calculation.ResultsThis study enrolled 24 eyes of 24 patients undergoing combined PC-pIOL removal and cataract surgery at Xiamen Eye Center of Xiamen University, Xiamen, Fujian, China. The median absolute prediction error in ascending order was EVO 2.0 (0.33), Kane (0.35), SRK/T-WKmodified (0.42), Holladay 1-WKmodified (0.44), Haigis-WKC1 (0.46), Pearl-DGS (0.47), BUII (0.58), Haigis (0.75), SRK/T (0.79), and Holladay 1 (1.32). The root-mean-square absolute error in ascending order was Haigis-WKC1 (0.591), Holladay 1-WKmodified (0.622), SRK/T-WKmodified (0.623), EVO (0.673), Kane (0.678), Pearl-DGS (0.753), BUII (0.863), Haigis (1.061), SRK/T (1.188), and Holladay 1 (1.513). A detailed analysis of ACD and LT measurement error revealed negligible impact on refractive outcomes in BUII and EVO 2.0 when these parameters were incorporated or omitted in the formula calculation.ConclusionThe Kane, EVO 2.0, and traditional formulas with WK AL adjustment displayed high prediction accuracy. Furthermore, the ACD and LT measurement error does not exert a significant influence on the accuracy of IOL power calculation formulas in highly myopic eyes implanted with PC-pIOL.

Optimizing SEM parameters for segmentation with AI – Part 1: Generating a training set

Extracting significant quantitative results from SEM images requires feature segmentation with image processing software. The efficiency of segmentation algorithms depends on the image quality, determined by the parameters set on the microscope during acquisitions. By integrating AI within SEM acquisition workflows, it is possible to suggest microscope parameters that will produce images where the features to quantify will be easily segmented. Specifically, a model is trained to automatically suggest the beam energy and probe current to set on the microscope during acquisitions. This paper is the first of two parts, describing workflows for generating a complete training set. The training set is carefully designed, consisting of both simulated data and real data acquired on the SEM by varying the energy and current. Separate workflows are required for generating simulated and acquired training examples. Simulated data generation is accomplished with the MC X-ray simulator in Dragonfly, where multiple virtual samples are created to intentionally diversify the training set. Acquiring data on the SEM for training is a time-consuming process when compared to generating simulations and would ideally be avoided but is included here to determine the degree to which it is required. Using only simulated data for adequate training, we show that our data generation workflow can be fully automated and produces a considerable amount of high quality data rapidly and with minimal effort.

Segmental deformity markers offer novel indicators of deformity progression risk in deformity-matched adolescent idiopathic scoliosis patients.

Identification of adolescent idiopathic scoliosis (AIS) patients with mild curvatures who pose significant risk of progressing to severe levels of curvatures is of paramount importance for clinical care. This study aimed to compare segmental deformity changes in AIS sub-cohorts that are dichotomised by progression status. Thirty-six female participants with Lenke 1 AIS curves were investigated with sequential MRIs during growth. Scans were reformatted to measure orthogonal segmental parameters, including sagittal/coronal wedging angles and axial rotation angles. Participants were dichotomised by progression. Two-tailed, independent sample t-tests were used to compare sub-cohort multi-segmental and segmental deformity parameters. Measurements were compared at each scan number and variable rates of change were determined using actual time between measures. AIS progression status sub-cohorts were comparable at scan 1 for multi-segmental deformity parameters (e.g. major thoracic curve angle, rib hump, kyphosis) (P > 0.05). However, apical measures of coronal IVD wedging, axial IVD rotation and axial vertebral rotation were segmental parameters at scan 1 which were larger for participants whose AIS would later go on to clinically progress (all P < 0.05). Measures of segmental hypokyphosis were comparable between groups. As development was tracked at each subsequent scan, coronal and axial plane differences between groups increased in both magnitude and number of differences. Initial disparity and then subsequent increasing magnitude of change of axial rotation may indicate a higher propensity to clinically progress in the future. This knowledge hopes to provide useful management information for AIS care providers and prognostic education for patients alike. II.

RECOMMENDATIONS ON THE URBAN NETWORK FOTL STRUCTURE WITH THE LOWEST POSSIBLE LEVEL OF DISTORTION OF INFORMATION AND CONTROL ILCF-SIGNALS

The article studies the problem of construction of subscriber branched networks xPON/MAN/RoF, on the base of fiber-optic transmission lines, with the possibility of non-relational control. Namely, enabling transmission of control information as a part of subscriber signal. It is proposed to use instantaneous wavelength change function of the optical signal (ILCF)as the control information with parametric characteristics. A method of modeling such segments was offerred, nature of ILCF was analyzed, and recommendations on inclusion of EDFA light guides and methods of pumping to them from the point of view of maintaining positive chirp for the information-control ILCF signal were made. It was assumed that ensuring positive chirp will minimize distortion of the latter during its transmission. It is concluded that branching has significant effect on ILCF. Recommended parameters of segments for different degrees of their branching are also obtained as well.

Real-time monitoring of middle cerebral artery blood flow using intraoperative transcranial doppler during trans-carotid artery revascularization

ObjectiveTranscarotid artery revascularization (TCAR) has emerged as a safe and effective method for carotid revascularization, offering several key advantages over carotid endarterectomy (CEA) and carotid artery stenting (CAS). Intraoperative transcranial Doppler (TCD) monitoring plays a pivotal role in assessing cerebral hemodynamics and detecting embolic signals during TCAR at our institution. MethodsThis review synthesizes the current literature and provides guidance for TCD monitoring throughout the various phases of TCAR, from preoperative assessment to postoperative management. Key considerations include probe placement, waveform evaluation, interpreting monitoring parameters such as mean flow velocity (MFV), pulsatility index (PI), and percentage change in the MFV (Δ%). Techniques for maintaining the insonation of the middle cerebral artery (MCA) M1 segment and optimal parameter settings for intraoperative TCD monitoring are detailed. ResultsTCAR phases are highlighted, including transcarotid access and vessel control, sheath insertion, the establishment of flow reversal, pre-dilation, stent placement, post-dilation, and closure, while emphasizing the importance of real-time feedback provided by TCD monitoring in identifying embolic signals and assessing changes in cerebral perfusion. The review discusses limitations of TCD monitoring, such as inadequate temporal windows, incorrect vessel identification and reliability issues with automatic emboli detection counters. Furthermore, practical advice is provided on how to navigate common pitfalls encountered during intraoperative TCD monitoring. ConclusionBy understanding the nuances of TCD monitoring and its application in TCAR, intraoperative TCD monitoring may aid to minimize the low but potential risk of intraprocedural embolic events, periprocedural hypoperfusion and postoperative hyperperfusion. Finally, we suggest opportunities for further research in embolization quantification and additional strategies to optimize quality control in TCAR.

Extraction of Brightness Values of Different Object from IRS &amp; Landsat Satellite Image : Comparative Study

The main aim of this research is to find optimum segmentation parameters for extracting different spectral values of a different object of Land sat and IRS image. A relatively new segmentation approach, multiresolution segmentation, is being examined using two data sets (Land sat and IRS).

The Influence of Corneal Thickness on Surgically Induced Corneal Astigmatism Derived from Total Keratometry Measured by Anterior Segment Swept-Source OCT.

The purposeof the study was to explore the possible correlations between the anterior segment parameters derived from anterior segment swept-source optical coherence tomography (AS-SS-OCT) with the surgically induced corneal astigmatism (CSIA) calculated from total keratometry (TK) measured by AS-SS-OCT. Seventy-one eyes of 67 patients with age-related cataract who underwent phacoemulsification combined with intraocular lens implantation with 2.2-mm incision were included. The CSIA values were calculated from anterior keratometry (CSIAKant) and TK (CSIATK) measured by AS-SS-OCT, respectively. Hotelling's T2 test was used to evaluate the difference. The correlation of CSIA with various parameters derived from AS-SS-OCT was tested with the Spearman correlation coefficient. The centroid of CSIAKant and of CSIATK were 0.31 ± 0.55 D @ 54° and 0.41 ± 0.59 D @ 51°, with no significant difference (F = 1.283, p = 0.281, Hotelling's T2). The mean absolute CSIAKant and CSIATK were 0.58 ± 0.24 D and 0.65 ± 0.28 D. Spearman test showed that the magnitude of CSIAKant was negatively correlated with preoperative peripheral corneal thickness (PCT, p = 0.045) and the magnitude of anterior keratometry (p = 0.044). The magnitude of CSIATK was negatively correlated with preoperative central corneal thickness (CCT, p = 0.003) and preoperative PCT (p = 0.015). The increased thickness of the peripheral cornea is correlated with the decrease in the magnitude of the CSIA. The correlation we identified between the corneal thickness and the CSIA indicated that certain preoperative parameters should be considered for the prediction of CSIA for a more precise refractive outcome.

Changes in the meander belt and channel pattern in the middle-low segment of the Cuarto river. Córdoba. Argentina

The Cuarto River is an important watercourse in the Córdoba Province, Argentina. Its middle-low segment crosses the eastern plains of this province, one of the most populated and (agricultural-livestock) productive regions of the country. In this segment, the channel and fluvial belt morphometric parameters exhibit notable changes downstream. Understanding the morphodynamics of the Cuarto River allows the characterization and definition of channel reach with tendencies towards migration, aggradation and overflow. In this way, it is possible to identify critical channel reaches, a fundamental aspect for effective planning. This work aims to characterize the downstream changes in the fluvial belt, meanders geometry, channel pattern and channel slope, along the middle-low segment of the Cuarto River and link these modifications with authigenic (sediment supply and transport regime) and allogenic controls. Five channel reaches (R1-R5) were selected according to geological-geomorphological criteria and different geometric parameters (channel width, channel slope, braided index, meander geometry, confinement degree) were determined for each of them. Empirical equations were used to establish relationships between these geometric parameters. Although most parameters showed a generally downward trend towards downstream reaches, marked changes were observed. Particularly, in the R1-R2 reaches, the fluvial belt widens and is unconfined, and the channel width and braided index also increases. The relationship between meander length/channel width (Lm/w) and radius of curvature/channel width (rc/w) obtained were within the ranges for free meanders (8–14) and high mobility (2–3), respectively. These parameter values are associated with alluvial channels and suggest limitations in transport and conditions for sedimentation. However, in R3, R4 and R5, the fluvial belt narrows and becomes confined, with high sinuosity, a reduction in the width of the channel and the braiding index. This pattern is expected for reaches characterized by predominance of transport and a tendency to a mixed or suspensive load. Moreover, both groups of reaches also exhibit an abrupt contrast in bedload size (from very coarse sand/gravel in R1 and R2 to fine/very fine sand in R3, R4, and R5). The similarity between the exponents of the predictive functions (Lm/w, rc/w, and Lm/rc) and those obtained for the Cuarto River, in addition to the satisfactory regression coefficients of the measured parameters suggest an acceptable balance between meander geometry and channel width regime of sediment transport. The middle-low reach of the Cuarto River shows notable changes, which can be linked to regional-scale allogenic factors such as morphostructures and lithology (R1-R2 with elevated morphostructure, R3-R4 are transitional reaches towards depressed plains, while R5 with subsidence environments). Nonetheless, the river demonstrates the capacity to regulate these factors at the reach level through authigenic processes. Thus the variability of channel width, channel slope, braiding index, meander geometry and degree of confinement are explained mainly by downstream changes in sediment supply and transport regime (authigenic controls) and secondarily by changes in regional slope and banks lithology (allogeneic controls).

Analysis of Face Milling of Hard Steel 55NiCrMoV7 by Studying Rough and Semi-Finished Machining and the Influence of Cutting Parameters on Macroscopic Chip Dimensions.

Hard milling is being increasingly used as an alternative to EDM due to its high productivity. The present paper presents the results of theoretical-experimental research on the face milling of hard steel 55NiCrMoV7. A comprehensive analysis of cutting temperatures and forces during single-tooth milling and a morphological examination of the resulting chips are conducted for roughing and semi-finishing operations. The temperature is analyzed in the chip formation area, and the detached chips and the cutting force are analyzed through their tangential, radial, and penetration components, depending on the contact angle of the cutter tooth with the workpiece. The analysis of chip morphology is carried out based on the dimensional and angular parameters of chip segmentation and their degree of segmentation. Based on the central composite design and the response surface method, it is shown that it is possible to mathematically model the dependence of the macroscopic dimensions of the detached chips on the cutting parameters. The determined process functions, the maximum chip curling diameter, and the maximum chip height allow for establishing the influence of the cutting parameters' values on the chips' macroscopic dimensions and, thus, guiding the cutting process in the desired direction.

The effect of epilepsy and anti-epileptic drugs on the anterior and posterior segment of the eye

ABSTRACT Clinical relevance Understanding the causes of visual symptoms in epilepsy patients is important for early diagnosis and taking precautions. Background The aim of this study is to evaluate the anterior and posterior segment parameters in patients with generalized tonic-clonic epilepsy (GTCE). Methods This retrospective study included 50 eyes of 50 patients with GTCE and 55 eyes of 55 healthy controls. For all participants, detailed ophthalmic examinations were obtained from the files of patients. Anterior segment parameters were measured using corneal topography and non-contact specular microscopy, and posterior segment parameters were measured using swept-source optical coherence tomography. Results The mean age of the patients with GTCE was 43.3 ± 13.2 years, and in the healthy controls it was 47.6 ± 10.7 years (p = 0.405). In GTCE patients, 34 patients were treated with monotherapy (MT) and 16 patients with polytherapy (PT). Central macular thickness (CMT) was statistically significantly thin in GTCE patients (p = 0.001). The average and four quadrants (superior, inferior, nasal, temporal) retinal nerve fibre layer (RNFL) were thinner in GTCE patients than in the healthy controls, but there was no statistically significant difference (p > 0.05, all). The central corneal thickness was statistically significantly thin in GTCE patients (p = 0.04). Endothelial cell density (ECD), endothelial cell number (ECN), and average cell area (ACA) were statistically significantly lower in GTCE patients than in the healthy controls (p < 0.05, all). Although the CMT, average, and four-quadrants RNFL were thinner in the PT group compared to the MT group, no statistically significant difference was observed (p > 0.05, all). Total high-order aberrations (HOAs) were 0.6 ± 0.4 in the MT group and 0.4 ± 0.1 in the PT group (p = 0.01). ECD, ECN, and ACA measurements were observed to be lower in the PT group compared to the MT group, but no statistically significant difference was detected (p > 0.05, all). Conclusion There could be statistically significant differences between GTCE patients and healthy controls in anterior and posterior segment parameters. This situation may be due to the epilepsy itself or to the antiepileptic drugs.

A method to enhance Apache Spark performance based on data segmentation and configuration parameters settings

When using modern big data processing tools, there is a problem of increasing the productivity of using modern frameworks in the context of effective setting of various configuration parameters. The object of the research is computational processes of processing big data with the use of technologies of high-performance frameworks. The subject is methods and approaches to the effective setting of configuration parameters of frameworks in the conditions of limitations of virtualization environments and local resources. The purpose of the study is to improve the performance of Apache Spark and Apache Hadoop deployment modes based on a combined approach that includes preprocess segmentation of input data and setting of basic and additional configuration parameters that take into account the limitations of the virtual environment and local resources. Achieving the set goal involves the following tasks: create a synthesized set of WordCount test data for using input data segmentation methods. Determine the composition of general and specific Apache Spark and Apache Hadoop configuration parameters that most affect the performance of frameworks in Spark Standalone and Hadoop Yarn (FIFO) deployment modes. Justify changes in the values of the configuration parameters (accepted by default) by setting the level of parallelism, the number of partitions of the input file according to the number of processor cores, the number of tasks assigned to each core and the system executor. Conduct experimental research to substantiate theoretical results and prove their use in practice. Methods. The research used the following methods: statistical analysis; a method of generating test data based on defined segmentation characteristics with arbitrary volumes of data; a systematic approach for comprehensive evaluation and analysis of performance of frameworks based on selected configuration parameters. The results. On the basis of the developed system of parameters for evaluating the performance of the studied frameworks, experiments were carried out, which include: the application of the method of segmentation of input data based on the division of the input file into paragraphs (lines) for different values of the ranges of the number of words and the number of letters in each word; setting the main parameters and specific ones, in particular, partitioning and parallelism, taking into account the characteristics of the virtual environment and the local resource. According to the obtained results, a detailed analysis of the use of the proposed methods to improve the performance of the studied frameworks with recommendations for choosing the optimal values of data segmentation parameters and configuration parameters was carried out. You are snowmen. The obtained results of the experiments allow us to conclude that the use of the proposed methods of setting the configuration parameters of Spark and Hadoop will increase the processing productivity: for small files (0.5–1 GB) on average up to 25–30%, for large ones (1.5–2.5 GB ) – up to 10–20% on average. At the same time, the average value of the execution time of one task decreased by 10-15% for files of different sizes and with different number of words in a line.

Evaluation of fetal cardiac morphology and function by fetal heart quantification technique in the normal second and third trimesters.

The study of fetal heart is receiving increasing attention. Fetal heart quantification (Fetal HQ) technology is a new speckle tracking technology that can analyze the 24-segment morphology and function of fetal ventricles. This study aims to use Fetal HQ to assess the changes in the structure and function of the fetal heart in normal mid to late pregnancy, providing a foundation for the clinical application of fetal cardiac speckle tracking technology. The heart size, global sphericity index (GSI), left ventricular [stroke volume (SV)], cardiac output (CO), ejection fraction (EF), global longitudinal strain (GLS), fractional area change (FAC), 24-segment end-diastolic diameter (EDD), sphericity index (SI) and fractional shortening (FS) of the two ventricles of 500 normal pregnant fetuses were evaluated by Fetal HQ. The subjects were divided into 5 groups according to gestational weeks (GA), and the changes of fetal heart morphology and function were observed. P<0.05 indicated the statistically significant difference. The fetal heart rate decreased gradually with the increase of GA (P<0.05). The size parameters of the fetal heart and two ventricles gradually increased with increasing GA (P<0.05). The 24 segments EDD of both ventricles increased with increasing GA (P<0.05), while the EDD increased first and then decreased from the ventricle base to the apex. The GSI and the 24 segments SI of two ventricles were basically not significantly different among the groups (P>0.05). The EF, GLS, FAC of the left ventricle and the GLS, FAC of the right ventricle decreased with the increase of GA (P<0.05), and SV and CO increased with increasing GA (P<0.05). The 24 segments FS of the left ventricle showed a downward trend with the increase of GA and gradually increased from the base to the apex. The FS of most segments of the right ventricle decreased with the increase of the GA and increased first and then decreased from the base to the apex. The whole and segmental size parameters of fetal heart can quantitatively evaluate the growth and development of fetal heart; the GSI and segmental SI are reliable morphological indexes for evaluating fetal heart; fetal ventricular function parameters EF, FAC, GLS and segmental FS can evaluate fetal cardiac function. The Fetal HQ technique can help us to evaluate the heart growth and development of normal fetuses in the second and third trimester of pregnancy.

An OpenSim thoracolumbar spine model applying a bottom-up modelling approach is similar to a top-down approach

The kinetic demands of the spine can be assessed using a top-down (TD) or bottom-up (BU) approach, which start calculations from the either the hands or from the feet, respectively. Biomechanists have traditionally favored a BU approach, though existing modeling approaches encourage a TD approach. Regardless of the approach the demands should be similar, provided the external forces and linked segment parameters are equivalently measured and modeled. Demonstrating a level of agreement between the two approaches can help evaluate a model. Further, having both approaches can be advantageous when data is inaccurate or unavailable for one. The purpose of this study was to compare the internal moments and forces at multiple lumbar and thoracic intervertebral joint (IVJ) levels during lifting tasks from an established OpenSim thoracolumbar spine model that applies a TD approach and a similar model modified to adopt a BU approach. Kinematics and external forces were recorded from twelve participants during sagittal and lateral lifts of different lifting speeds and crate masses. For both approaches IVJ kinetics were estimated using a standard OpenSim modeling pipeline. The BU and TD approach IVJ joint moments generally agreed both temporally (R2 = .94 ± .17) and in magnitude (RMSE=6.2 ± 3.5 Nm) of the primary planes of movement. There were however some temporal fit exceptions for off axes moments with low magnitudes (i.e., < 10 Nm). Bland-Altman plots also indicated acceptable agreement for IVJ peak forces (BU-TD difference of 12 ± 111 and 8 ± 31 N in compression and resultant shear, respectfully). These results support the application of the BU approach and the assigned linked segment parameters of the model. The new BU model is available on the SimTK site (https://simtk.org/projects/spine_ribcage).

Optimization of the SWAT+ model to adequately predict different segments of a managed streamflow hydrograph

ABSTRACT Complete representation of rainfall–runoff responses in complex, large watersheds using a single-objective parameterization approach in watershed models is often unachievable. In this study we present a calibration approach for the SWAT+ model that independently fits model parameters for different flow segments of the hydrograph. The approach is demonstrated for the Feather River, California, USA, using daily streamflow from the Lake Oroville Reservoir outlet gage. Results show that when model parameters were independently fitted for different flow segments the KGE, NSE, PBIAS, and RSR values improved to 0.96, 0.99, −3.3, and 0.10, respectively, compared to 0.72, 0.66, −9.30, and 0.53, respectively, achieved under a multiobjective and full hydrograph (average hydrograph) calibration. The results highlight that when considering the average hydrograph and flow duration curves, a more balanced representation of both poorly and well-performing segments is achieved, emphasizing the importance of segment-specific parameterization and multi-objective evaluation for accurately representing different flow conditions.

Crystalline lens clarity in patients treated with isotretinoin

ABSTRACT Clinical relevance Isotretinoin has been the best treatment option for moderate and severe acne vulgaris since the 1980s. Some studies have shown evidence of subclinical anterior segment involvement of the eye in patients treated with isotretinoin. Background This study aimed to evaluate lens clarity with the densitometry software of Scheimpflug tomography in patients treated with isotretinoin and to compare with healthy control subjects. Methods Thirty-seven acnepatients treated with isotretinoin who met the inclusion criteria (24 males and 13 females, mean age 22.94 ± 4.21 years) and 39 healthy control subjects were included in the study. Clinical characteristics of the isotretinoin and control subjects were recorded. Lens density was evaluated with the densitometry software of the Scheimpflug tomography device (PentacamHR, Oculus, Wetzlar, Germany). Results There was no statistically significant difference between the groups in age, gender distribution, spherical equivalent, or anterior segment parameters measured by the Pentacam system (p > 0.05 for all). Lens density values in zones 2 and 3 were significantly higher in the isotretinoin group (p = 0.042, p < 0.001) and positively correlated with cumulative isotretinoin dose (zone 2: r = 0.384, p = 0.032; zone 3: r = 0.384, p = 0.005). Conclusion Zone 2 and zone 3 lens density are higher in patients treated with isotretinoin when compared to healthy controls.

Aphakia treatment with sutureless scleral fixation or retropupillary iris-claw intraocular lens implantation: visual acuity, anterior segment and keratometry outcomes

PurposeEvaluation of anterior segment parameters using the Scheimpflug corneal topography 1 year after surgery in patients who underwent sutureless scleral fixation intraocular lens (SFIOL) implantation using the modified Yamane technique and retropupillary iris-claw intraocular lens (RPIOL) implantation.MethodsA total of 60 eyes from 57 patients who underwent sutureless SFIOL implantation and 57 eyes from 52 patients who underwent RPIOL implantation were included. Anterior chamber depth (ACD), anterior chamber angle (ACA), anterior chamber volume (ACV), anterior–posterior corneal astigmatism, and keratometric values were assessed using the Scheimpflug corneal topography (Pentacam HR, Germany).ResultsThere was no statistically significant difference in postoperative UCVA and BCVA between the sutureless SFIOL and the RPIOL group (p = 0.236, p = 0.293, respectively). While there was no statistically significant difference in postoperative IOP between the two groups (p = 0.223), a statistically significant decrease in IOP was observed in both groups (p < 0.001). While there was no statistical difference between the sutureless SFIOL group and the RPIOL group in terms of spherical value (p = 0.441) and spherical equivalence (p = 0.237), there was a statistically significant difference in cylindrical value (p < 0.001). While there was a statistical difference in anterior astigmatism (p < 0.001), there was no statistical difference in posterior astigmatism (p = 0.405). There was no statistical difference in terms of ACV, ACD, and ACA between the sutureless SFIOL and the RPIOL group (p = 0.812, p = 0.770, p = 0.401, respectively).ConclusionIn this study, although there was a statistical difference in cylindrical value and anterior corneal astigmatism between the sutureless SFIOL and RPIOL groups, vision was not affected. According to this study, sutureless SFIOL and RPIOL are two successful methods in terms of visual acuity, anterior segment, and keratometry outcomes in aphakic patients after phacoemulsification.

Myocardial viability under various ischemic burdens in chronic total occlusions: A stress-cardiac magnetic resonance study

ObjectivesThis study aimed to analyze each myocardial segment's ischemic burden, scarring, function, and viability by late gadolinium enhancement (LGE) imaging and stress-MRI using adenosine. Materials and methodsSemi-quantitative and qualitative parameters of myocardial segments were obtained by stress-MRI. Moreover, segments without perfusion defect were defined as the no ischemic group, segments with a perfusion defect of ≤50% were defined as a low ischemic burden group, and segments with a perfusion defect of >50% were defined as a high ischemic burden group. “Segmental wall thickening (SWT)” was defined as the absolute difference between the end-diastolic and end-systolic wall thickness. Finally, viability was defined by dysfunctional myocardium (<3 ​mm segmental wall thickening [SWT]) and ≤50% late gadolinium enhancement (LGE). ResultsA total of 445 segments in the CTO territory were analyzed, scar tissue was found in the CTO territory, with LGE evident in 18.2% of CTO segments totaling >50%. Among the different ischemic burden groups, there were significant differences in LGE volume (p ​< ​0.01), and the trend of SWT was consistent with the degree of myocardial ischemia. The incidence of ≤50% LGE and viable myocardium was higher in segments of the no ischemia and low ischemic burden groups. However, there was no significant difference in the incidence of dysfunctional myocardial segments among the three groups (P ​> ​0.05). ConclusionsStress MRI parameters can accurately and detailly assess myocardial viability and function, so multi-parameter joint assessment of CTO patients by stress MRI may help in treatment decisions.

How automated techniques ease functional assessment of the fetal heart: Applicability of two-dimensional speckle-tracking echocardiography for comprehensive analysis of global and segmental cardiac deformation using fetalHQ®.

Prenatal echocardiographic assessment of fetal cardiac function has become increasingly important. Fetal two-dimensional speckle-tracking echocardiography (2D-STE) allows the determination of global and segmental functional cardiac parameters. Prenatal diagnostics is relying increasingly on artificial intelligence, whose algorithms transform the way clinicians use ultrasound in their daily workflow. The purpose of this study was to demonstrate the feasibility of whether less experienced operators can handle and might benefit from an automated tool of 2D-STE in the clinical routine. A total of 136 unselected, normal, singleton, second- and third-trimester fetuses with normofrequent heart rates were examined by targeted ultrasound. 2D-STE was performed separately by beginner and expert semiautomatically using a GE Voluson E10 (FetalHQ®, GE Healthcare, Chicago, IL). Several fetal cardiac parameters were calculated (end-diastolic diameter [ED], sphericity index [SI], global longitudinal strain [EndoGLS], fractional shortening [FS]) and assigned to gestational age (GA). Bland-Altman plots were used to test agreement between both operators. The mean maternal age was 33 years, and the mean maternal body mass index prior to pregnancy was 24.78kg/m2. The GA ranged from 16.4 to 32.0weeks (average 22.9weeks). Averaged endoGLS value of the beginner was -18.57%±6.59 percentage points (pp) for the right and -19.58%±5.63 pp for the left ventricle, that of the expert -14.33%±4.88 pp and -16.37%±5.42 pp. With increasing GA, right ventricular endoGLS decreased slightly while the left ventricular was almost constant. The statistical analysis for endoGLS showed a Bland-Altman-Bias of -4.24 pp±8.06 pp for the right and -3.21 pp±7.11 pp for the left ventricle. The Bland-Altman-Bias of the ED in both ventricles in all analyzed segments ranged from -.49mm±1.54mm to -.10mm±1.28mm, that for FS from -.33 pp±11.82 pp to 3.91 pp±15.56 pp and that for SI from -.38±.68 to -.15±.45. Between both operators, our data indicated that 2D-STE analysis showed excellent agreement for cardiac morphometry parameters (ED and SI), and good agreement for cardiac function parameters (EndoGLS and FS). Due to its complexity, the application of fetal 2D-STE remains the domain of scientific-academic perinatal ultrasound and should be placed preferably in the hands of skilled operators. At present, from our perspective, an implementation into clinical practice "on-the-fly" cannot be recommended.

Correlations of Corneal Endothelial Morphology and Corneal Thickness With Anterior Segment Parameters in Healthy Individuals.

The purpose of this study was to investigate the associations between central corneal endothelial cell density (ECD), endothelial morphology, and corneal thickness (central corneal thickness) with the anterior chamber depth, corneal volume (CV), white-to-white (WTW) distance, mean anterior chamber angle (CAmean), and gender in healthy individuals. This observational study included 136 healthy volunteers. The ECD, coefficient of variation of cell area, and hexagonal cell appearance ratio (%Hex) were measured by means of specular microscopy. The central corneal thickness, anterior chamber depth, CV, WTW distance, and the angle width of 12 points were taken by the Pentacam HR Scheimpflug anterior segment imaging. The arithmetical mean of the 12 points was considered as the CAmean. We used mixed effect linear regression model for the statistical analysis of the data. ECD was positively correlated with CV ( P = 0.028), while after adjusting for age, it was negatively correlated with age ( P < 0.001). Coefficient of variation of cell area was positively correlated with CAmean ( P = 0.036), while after adjusting for age, it was positively correlated with age ( P < 0.001) and CAmean ( P = 0.005). Hex was negatively correlated with WTW ( P = 0.023) and CAmean ( P = 0.025), and after adjusting for age, this correlation remained the same ( P = 0.029 when correlated with WTW and P = 0.035 with CAmean). There were significant changes in the morphology of the corneal endothelial cells in eyes with wider anterior chamber angle. Greater pleomorphism and polymegethism of the corneal endothelium was observed in healthy patients with wider CAmean. Deepening of the anterior chamber as myopia progresses could render the corneal endothelium more fragile and susceptible to mechanical stress, which is an area worthy of further study.