Quantification Software Research Articles

Real-time automatic quantification of left ventricular function by hand-held ultrasound devices in patients with suspected heart failure: a feasibility study of a diagnostic test with data from general practitioners, nurses and cardiologists

ObjectivesTo evaluate the feasibility and reliability of hand-held ultrasound (HUD) examinations with real-time automatic decision-making software for ejection fraction (autoEF) and mitral annular plane systolic excursion (autoMAPSE) by novices (general...

Gestational Age-Adjusted Reference Ranges for Fetal Left Ventricle Longitudinal Strain by Automated Cardiac Motion Quantification between 24 and 37 Weeks’ Gestation

Introduction: The objective of this study was to construct gestational age (GA) based reference values for left ventricle (LV) longitudinal strain in normal fetuses, between 24 and 37 weeks’ gestation, assessing its feasibility and reproducibility with automated cardiac motion quantification software (aCMQ-QLab), which is widely used in postnatal echocardiography. Methods: This prospective study included healthy gravid women with singleton pregnancies and no evidence of fetal structural cardiovascular disease. Fetal echocardiographies were performed between 24 and 37 GA. 2D four-chamber view clips were recorded and LV longitudinal strain was analyzed offline. Intra- and interobserver reproducibility between 2 independent observers was evaluated by intraclass correlation coefficients (ICC) and Bland-Altman scatterplots. Regression analysis was used to determine GA adjusted reference ranges and construct nomograms. Results: LV longitudinal strain measurements were feasible in 95.4% of acquisitions. 435 clips were obtained. Intra- and interobserver ICC were 0.998 (95% CI 0.997–0.999) and 0.991 (95% CI 0.984–0.995), respectively. The global longitudinal strain and the middle and apical LV segments showed progressive decline as GA advanced, whereas the basal segments remained stable. Conclusions: Assessment of LV longitudinal strain by aCMQ-QLab is feasible, reproducible, and within normal ranges. Our results offer more information regarding fetal cardiac function assessment with 2D speckle tracking techniques, aiding in the introduction of this software into research practice, encouraging the realization of more studies, and probably helping in its future use in clinical practice, allowing longitudinal surveillance of strain without intervendor variability and aiding in follow-up of fetal cardiac conditions before and after birth, as it is the most commonly used software postnatally.

First in-human quantitative plaque characterization with ultra-high resolution coronary photon-counting CT angiography.

PurposeTo assess the effect of ultra-high-resolution coronary CT angiography (CCTA) with photon-counting detector (PCD) CT on quantitative coronary plaque characterization.Materials and methodsIn this IRB-approved study, 22 plaques of 20 patients (7 women; mean age 77 ± 8 years, mean body mass index 26.1 ± 3.6 kg/m2) undergoing electrocardiography (ECG)-gated ultra-high-resolution CCTA with PCD-CT were included. Images were reconstructed with a smooth (Bv40) and a sharp (Bv64) vascular kernel, with quantum iterative reconstruction (strength level 4), and using a slice thickness of 0.6, 0.4, and 0.2 mm, respectively (field-of-view 200 mm × 200 mm, matrix size 512 × 512 pixels). Reconstructions with the Bv40 kernel and slice thickness of 0.6 mm served as the reference standard. After identification of a plaque in coronary arteries with a vessel diameter ≥2 mm, plaque composition was determined using a dedicated, semi-automated plaque quantification software. Total plaque, calcified, fibrotic, and lipid-rich plaque components were quantified in all datasets.ResultsMedian plaque volume was highest (23.5 mm3, interquartiles 17.9–34.3 mm3) for reconstructions with the reference standard and lowest for ultra-high-resolution reconstructions with a slice thickness of 0.2 mm and the Bv64 kernel (18.1 mm3, interquartiles 14.1–25.8 mm3, p < 0.001). Reconstructions with the reference standard showed largest calcified (85.1%, interquartiles 76.4–91.1%) and smallest lipid-rich plaque components (0.5%, interquartiles 0.0–1.5%). Smallest calcified plaque components (75.2%, interquartiles 69.9–80.8%) and largest lipid-rich components (6.7%, interquartiles 5.1–8.4%) were found for ultra-high-resolution reconstructions with a slice thickness of 0.2 mm and the Bv64 kernel. At an identical slice thickness, volume of calcified components was always lower, and volume of lipid-rich components was always higher for reconstructions with the Bv64 kernel compared with reconstructions with the Bv40 kernel (all, p < 0.001).ConclusionThis patient study indicates significant differences of ultra-high-resolution scanning with PCD-CT on quantitative coronary plaque characterization. Reduced blooming artifacts may allow improved visualization of fibrotic and lipid-rich plaque components with the ultra-high-resolution mode of PCD-CT.

Left ventricular volume and ejection fraction measurements by fully automated 3D echocardiography left chamber quantification software versus CMR: A systematic review and meta-analysis

BackgroundAlthough transthoracic three-dimensional echocardiography (3DE) is now recommended by guidelines for left ventricular (LV) volumetric measurements, widespread implementation has been limited due to time constraints and required expertise. We hypothesized that fully automated 3DE left chamber quantification software might provide accurate measurements, and that its application could eliminate these obstacles. MethodsTo address this hypothesis, we conducted a systematic review and meta-analysis following a search for studies that compared LV volumes and ejection fraction (EF) using fully automated 3DE software (HeartModel or Dynamic HeartModel, Philips Healthcare, Andover, MA, USA) with cardiac magnetic resonance (CMR), from 2015 to 2021. A random effects model was used to determine biases, correlations, and 95 % confidence intervals (CI) of LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF. Subgroup and meta-regression analyses were performed to determine effects of moderators on the outcome. ResultsOf 12 studies (616 subjects), mean differences and 95 % CIs in EDV, ESV, and EF between fully automated 3DE software and CMR were −19.6 mL (95 % CI; −27.6 to −11.5 mL), −11.4 mL (−16.7 to −6.2 mL), and 0.4 % (−1.1 to 2.0 %), respectively. Corresponding correlation values between the two methods were 0.91 (0.86–0.94), 0.89 (0.82–0.93), and 0.85 (0.81–0.88), respectively. Meta-regression analysis revealed that there were no effects of either publication year, type of software, or type of analysis on the outcome of LV volumetric and functional parameters except for publication year on LVESV correlation values. ConclusionsAlthough 3DE still underestimates LV volumes, the observed differences were no >20 mL. EF showed similar values to CMR. Excellent correlations between the two techniques make fully automated 3DE left chamber quantification software useful for routine clinical practice in adult population.

The focused beam X-ray fluorescence elemental quantification software package PIQUANT

Adoption of a robust X-ray fluorescence spectroscopy quantification and spectrum fitting routine calls for careful consideration on the inner workings and databases incorporated in its architecture. For analysis of micro-XRF data returned from the Planetary Instrument for X-ray Lithochemistry (PIXL), integrated on the Mars 2020 Perseverance rover, the University of Washington and the National Aeronautics and Space Administration (NASA) have invested in the production of an in-house micro-XRF software package, PIQUANT, capable of supporting quantitative elemental analysis of whole rock and geological materials. The PIQUANT software uses an iterative fundamental parameters physics-based model to convert X-ray peak intensity into elemental concentration, and has minimal reliance on calibration using standards. It also incorporates polycapillary optic transmission correction to account for photon passage in the X-ray optic of micro-XRF systems. This work introduces the key features of PIQUANT's architecture, its databases, models, assumptions and summarizes features available as part of the analysis products it generates. A working example of a quantification process available with this software is presented within.

Lesions in White Matter in Wilson's Disease and Correlation with Clinical Characteristics.

Neuroimaging studies in Wilson's disease (WD) have identified various alterations in white matter (WM) microstructural organization. However, it remains unclear whether these alterations are localized to specific regions of fiber tracts, and what diagnostic value they might have. The purpose of this study is to explore the spatial profile of WM abnormalities along defined fiber tracts in WD and its clinical relevance. Ninety-nine patients with WD (62 men and 37 women) and 91 age- and sex-matched controls (59 men and 32 women) were recruited to take part in experiments of diffusion-weighted imaging with 64 gradient vectors. The data were calculated by FMRIB Software Library (FSL) software and Automated Fiber Quantification (AFQ) software. After registration, patient groups and normal groups were compared by Mann-Whitney U test analysis. Compared with the controls, the patients with WD showed widespread fractional anisotropy reduction and mean diffusivity, radial diffusivity elevation of identified fiber tracts. Significant correlations between diffusion tensor imaging (DTI) parameters and the neurological Unified Wilson's Disease Rating Scale (UWDRS-N), serum ceruloplasmin, and 24-h urinary copper excretion were found. The present study has provided evidence that the metrics of DTI could be utilized as a potential biomarker of neuropathological symptoms in WD. Damage to the microstructure of callosum forceps and corticospinal tract may be involved in the pathophysiological process of neurological symptoms in WD patients, such as gait and balance disturbances, involuntary movements, dysphagia, and autonomic dysfunction.

NMRpQuant: an automated software for large scale urinary total protein quantification by one-dimensional 1H NMR profiles.

Summary 1H nuclear magnetic resonance (NMR) spectroscopy is an established bioanalytical technology for metabolic profiling of biofluids in both clinical and large-scale population screening applications. Recently, urinary protein quantification has been demonstrated using the same 1D 1H NMR experimental data captured for metabolic profiling. Here, we introduce NMRpQuant, a freely available platform that builds on these findings with both novel and further optimized computational NMR approaches for rigorous, automated protein urine quantification. The results are validated by interlaboratory comparisons, demonstrating agreement with clinical/biochemical methodologies, pointing at a ready-to-use tool for routine protein urinalyses.Availability and implementation NMRpQuant was developed on MATLAB programming environment. Source code and Windows/macOS compiled applications are available at https://github.com/pantakis/NMRpQuant, and working examples are available at https://doi.org/10.6084/m9.figshare.18737189.v1.Supplementary information Supplementary data are available at Bioinformatics online.

HARLEY mitigates user bias and facilitates efficient quantification and co-localization analyses of foci in yeast fluorescence images

Quantification of cellular structures in fluorescence microscopy data is a key means of understanding cellular function. Unfortunately, numerous cellular structures present unique challenges in their ability to be unbiasedly and accurately detected and quantified. In our studies on stress granules in yeast, users displayed a striking variation of up to 3.7-fold in foci calls and were only able to replicate their results with 62–78% accuracy, when re-quantifying the same images. To facilitate consistent results we developed HARLEY (Human Augmented Recognition of LLPS Ensembles in Yeast), a customizable software for detection and quantification of stress granules in S. cerevisiae. After a brief model training on ~ 20 cells the detection and quantification of foci is fully automated and based on closed loops in intensity contours, constrained only by the a priori known size of the features of interest. Since no shape is implied, this method is not limited to round features, as is often the case with other algorithms. Candidate features are annotated with a set of geometrical and intensity-based properties to train a kernel Support Vector Machine to recognize features of interest. The trained classifier is then used to create consistent results across datasets. For less ambiguous foci datasets, a parametric selection is available. HARLEY is an intuitive tool aimed at yeast microscopy users without much technical expertise. It allows batch processing of foci detection and quantification, and the ability to run various geometry-based and pixel-based colocalization analyses to uncover trends or correlations in foci-related data. HARLEY is open source and can be downloaded from https://github.com/lnilya/harley.

Repeatability and Reproducibility of 4.5 by 4.5 mm Peripapillary Optical Coherence Tomography Angiography Scans in Glaucoma and Non-Glaucoma Eyes.

Peripapillary vessel parameters from optical coherence tomography angiography (OCTA) 4.5×4.5 mm scans in nonglaucomatous and glaucomatous eyes showed high repeatability and reproducibility, with higher reliability for commercially developed OCTA parameters compared with custom OCTA parameters. The purpose of this study was to assess intrasession repeatability versus intersession reproducibility of peripapillary vessel parameters from 4.5×4.5 mm OCTA scans in nonglaucomatous eyes and glaucomatous eyes. In a longitudinal study, peripapillary OCTA scans were quantified using research-oriented custom quantification software that calculated vessel area density (VAD) and flux and clinic-oriented commercially developed software (Cirrus 11.0) that calculated perfusion density (PD) and flux index (FI). Intrasession repeatability and intersession reproducibility were evaluated using within-eye coefficient of variation (CV W ) and intraclass correlation coefficient (ICC). With 127 nonglaucomatous eyes, intrasession CV W for VAD, PD, flux, and FI were 1.900%, 1.174%, 2.787%, and 1.425%, respectively. The intersession CV W were 2.039%, 1.606%, 4.053%, and 2.798%, respectively. Intrasession ICC ranged from 0.903 to 0.956, and intersession ICC ranged from 0.850 to 0.896. Among 144 glaucomatous eyes, intrasession CV W for VAD, PD, flux, and FI were: 3.841%, 1.493%, 5.009%, and 2.432%, respectively. The intersession CV W were 4.991%, 2.155%, 6.360%, and 3.458%, respectively. Intrasession ICC ranged from 0.956 to 0.969, and intersession ICC ranged from 0.918 to 0.964. Among nonglaucomatous and glaucomatous eyes, the majority of peripapillary OCTA vessel parameters from 4.5×4.5 mm scans had greater intrasession repeatability than intersession reproducibility. There was a greater agreement for the commercially developed quantification parameters than for their custom quantification counterparts.

Three-dimensional echocardiographic assessment of left ventricular volume in different heart diseases using a fully automated quantification software.

BACKGROUNDHeartModel (HM) is a fully automated adaptive quantification software that can quickly quantify left heart volume and left ventricular function. This study used HM to quantify the left ventricular end-diastolic (LVEDV) and end-systolic volumes (LVESV) of patients with dilated cardiomyopathy (DCM), coronary artery heart disease with segmental wall motion abnormality, and hypertrophic cardiomyopathy (HCM) to determine whether there were differences in the feasibility, accuracy, and repeatability of measuring the LVEDV, LVESV, LV ejection fraction (LVEF) and left atrial end-systolic volume (LAESV) and to compare these measurements with those obtained with traditional two-dimensional (2D) and three-dimensional (3D) methods.AIMTo evaluate the application value of HM in quantifying left heart chamber volume and LVEF in clinical patients.METHODSA total of 150 subjects who underwent 2D and 3D echocardiography were divided into 4 groups: (1) 42 patients with normal heart shape and function (control group, Group A); (2) 35 patients with DCM (Group B); (3) 41 patients with LV remodeling after acute myocardial infarction (Group C); and (4) 32 patients with HCM (Group D). The LVEDV, LVESV, LVEF and LAESV obtained by HM with (HM-RE) and without regional endocardial border editing (HM-NE) were compared with those measured by traditional 2D/3D echocardiographic methods to assess the correlation, consistency, and repeatability of all methods.RESULTS(1) The parameters measured by HM were significantly different among the groups (P < 0.05 for all). Compared with Groups A, C, and D, Group B had higher LVEDV and LVESV (P < 0.05 for all) and lower LVEF (P < 0.05 for all); (2) HM-NE overestimated LVEDV, LVESV, and LAESV with wide biases and underestimated LVEF with a small bias; contour adjustment reduced the biases and limits of agreement (bias: LVEDV, 28.17 mL, LVESV, 14.92 mL, LAESV, 8.18 mL, LVEF, -0.04%). The correlations between HM-RE and advanced cardiac 3D quantification (3DQA) (rs = 0.91-0.95, P < 0.05 for all) were higher than those between HM-NE (rs = 0.85-0.93, P < 0.05 for all) and the traditional 2D methods. The correlations between HM-RE and 3DQA were good for Groups A, B, and C but remained weak for Group D (LVEDV and LVESV, rs = 0.48-0.54, P < 0.05 for all); and (3) The intraobserver and interobserver variability for the HM-RE measurements were low.CONCLUSIONHM can be used to quantify the LV volume and LVEF in patients with common heart diseases and sufficient image quality. HM with contour editing is highly reproducible and accurate and may be recommended for clinical practice.

Neurochemical Profile of Enteric Neurons in the Submucosal Plexuses of Pig vs. Human Colon

The enteric nervous system (ENS), the neural network that controls gastrointestinal functions, varies among species. This is particularly evident for the submucosal plexus that is multilayered in humans but single layered and much less developed in rodents and guinea pigs often used for ENS studies. The submucosal plexus plays a major role in the control of gut functions. The pig has many homologies with humans, including a well‐developed submucosal plexus with an inner submucous plexus (ISP) near the mucosa and an outer submucous plexus (OSP) near the circularmuscle, as in humans. We have previously shown that in the adult pig colon, the density of enteric neurons is significantly higher in the ISP than OSP in ascending (AC) and descending (DC) colon, and that neurons in both plexuses contain choline acetyltransferase (ChAT) immunoreactivity (IR) and neuronal nitric oxide synthase (nNOS)‐IR, markers of the major excitatory (acetylcholine) and inhibitory (nitric oxide) transmitters with a small subpopulation containing both transmitters (Cell Tissue Res. 2021;383(2):645‐654). In this study, we compared the density and neurochemical profile of enteric neurons of the ISP and OSP in the AC and DC of the adult pig (16 Yucatan pigs, 3 F,25‐30 kg) and humans. Human specimens were obtained from 14 patients (6 F, age 48‐86) undergoing elective surgery for colon adenocarcinoma and were taken from the uninvolved resection margin. We used HuC/D (pan‐neuronal marker), ChAT, nNOS and substance P (SP) antibodies in whole mount preparations of the submucosa, confocal imaging and Imaris software for quantification. In both pig and human colon, the highest density of neurons was observed in the ISP of the AC, though the overall density of HuC/D‐IR neurons was about 4 times higher in pig vs. human. As observed in the pig colon, the density of HuC/D‐IR neurons in the ISP of the AC was significantly higher than the ISP of the DC (P&lt;0.01), whereas neuronal density in OSP of AC and DC were not significantly different. The ganglia were also smaller in human ISP and OSP throughout the colon (average ranging from 13‐28 neurons/ganglion) compared to pig where average neurons/ganglion ranged from 30‐120. The % of ChAT‐IR neurons in human (38‐44%) and pig (30‐44%) colon was comparable with no differences between ISP and OSP in AC and DC. The % of nNOS‐IR neurons in human colon was similar in the ISP and OSP of AC and DC (16‐22%), which differs from the pig, where the % of nNOS‐IR neurons in the ISP of AC was significantly lower than OSP (15% vs. 45%) and both ISP and OSP of DC (38‐42%). Overall, the density of nNOS‐IR neurons in human colon was lower compared to the pig colon. The % of SP‐IR neurons was slightly lower in human (15‐20%) vs. pig (23‐26%) colon in both plexuses in the AC and DC. There were dense SP‐IR varicosities through the ganglia in both pig and human colon. SP‐IR mostly colocalized with ChAT‐IR but was also observed in a subpopulation of nNOS‐IR and of nNOS/ChAT‐IR neurons in both human and pig colon. Overall, except for a few differences in neuronal density, there are neurochemical similarities that support the validity of the pig as pre‐clinical model for translational research to explore neuromodulation in colonic disorders in humans.

Quantitative imaging analysis detects subtle airway abnormalities in symptomatic military deployers

BackgroundExposure to inhalational hazards during post-9/11 deployment to Southwest Asia and Afghanistan puts military personnel at risk for respiratory symptoms and disease. Pulmonary function and qualitative chest high resolution computed tomography (HRCT) are often normal in “deployers” with persistent respiratory symptoms. We explored the utility of quantitative HRCT imaging markers of large and small airways abnormalities, including airway wall thickness, emphysema, and air trapping, in symptomatic deployers with clinically-confirmed lung disease compared to controls.MethodsChest HRCT images from 45 healthy controls and 82 symptomatic deployers with asthma, distal lung disease or both were analyzed using Thirona Lung quantification software to calculate airway wall thickness (by Pi10), emphysema (by percentage of lung volume with attenuation < -950 Hounsfield units [LAA%-950]), and three parameters of air trapping (expiratory/inspiratory total lung volume and mean lung density ratios, and LAA%-856). SAS v.9.4 was used to compare demographic and clinical characteristics between deployers and controls using Chi-Square, Fisher Exact or t-tests. Linear regression was used to assess relationships between pulmonary function and quantitative imaging findings.ResultsGender and smoking status were not statistically significantly different between groups, but deployers were significantly younger than controls (42 vs 58 years, p < 0.0001), had higher body mass index (31 vs 28 kg/m2, p = 0.01), and had fewer total smoking pack-years (8 vs. 26, p = 0.007). Spirometric measures were not statistically significantly different between groups. Pi10 and LAA%-950 were significantly elevated in deployers compared to controls in unadjusted analyses, with the emphysema measure remaining significantly higher in deployers after adjustment for age, sex, smoking, BMI, and expiratory total lung volume. Air trapping parameters were more common in control images, likely due to differences in age and smoking between groups. Among deployers, LAA%-950 and Pi10 were significantly correlated with spirometric markers of obstruction based on ratio of forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) and/or percent predicted FEV1.ConclusionsQuantitative chest HRCT imaging analysis identifies emphysema in deployers with asthma and distal lung disease, and may be useful in detecting and monitoring deployment-related lung disease in a population where spirometry is typically normal.

CVIS: Automated OCT‐scan‐based software application for the measurements of choroidal vascularity index and choroidal thickness

To develop an automated image recognition software for the objective quantification of choroidal vascularity index (CVI) and choroidal thickness (CT) at different choroidal locations on images obtained from enhanced depth imaging optical coherence tomography (EDI-OCT), and to validate its reliability and investigate the difference and correlation between measurements made by manual and software. A total of 390 EDI-OCT scans, captured from 130 eligible emmetropic or myopic subjects, were categorized into four grades in terms of their accessibility to identify the choroidal-scleral interface (CSI) and were further assessed for CT and CVI at five locations (subfoveal, nasal, temporal, superior and inferior) by the newly developed Choroidal Vascularity Index Software (CVIS) and three ophthalmologists. Choroidal parameters acquired from CVIS were evaluated for its reliability and correlation with ocular factors, in comparison to manual measurements. Distribution of difference and correlation coefficient between CVIS and manual measurements were also analysed. Choroidal Vascularity Index Software (CVIS) demonstrated excellent intra-session reliability for CT (ICC: 0.992) and CVI (ICC: 0.978) measurements, compared to the relatively lower intra- and inter-observer reliability of manual measurements. Choroidal Vascularity Index Software (CVIS) and manual assessments had the highest correlation at nasal choroid (CT: r = 0.829, p < 0.001; CVI: r = 0.665, p < 0.001). Choroidal parameters identified with CVIS showed stronger correlations with axial length than manual measurements. This automated software, CVIS, exhibited excellent reliability compared to manual measurements, which are subject to image quality and clinical experience. With its validated clinical relevance, CVIS holds promise to serve as a flexible and robust tool in future vitreoretinal and chorioretinal studies.

Intrasession Repeatability and Intersession Reproducibility of Macular Vessel Parameters on Optical Coherence Tomography Angiography in Glaucomatous and Non-Glaucomatous Eyes

Purpose Using optical coherence tomography angiography (OCTA), this study compared intrasession repeatability versus intersession reproducibility of macular vessel parameters in glaucoma and non-glaucoma subjects. Methods 6 × 6 mm2 macular OCTA scans (Cirrus HD-OCT 5000) were acquired from glaucomatous and non-glaucomatous subjects as part of an observational, longitudinal study. Vessel area density (VAD) and vessel skeleton density (VSD) were calculated using research-based quantification software while perfusion density (PDZ) and vessel density (VDZ) were calculated using commercially developed software (Cirrus 11.0, Carl Zeiss Meditec). Intrasession repeatability and intersession reproducibility were determined using within-eye standard deviation (SW), within-eye coefficient of repeatability (CRW), within-eye coefficient of variation (CVW), and intraclass correlation coefficients (ICC). Results The intrasession repeatability and intersession reproducibility for macular OCTA parameters were similar to one another for both non-glaucomatous and glaucomatous eyes. Intrasession CVW from the non-glaucoma group (n = 73) was 1.097% for VAD, 1.007% for VSD, 2.980% for PDZ, and 2.714% for VDZ. Intersession CVW from the non-glaucoma group (n = 55) was 1.389% for VAD, 1.279% for VSD, 2.935% for PDZ, and 2.695% for VDZ. Intrasession CVW from the glaucoma group (n = 59) was 1.189% for VAD, 0.970% for VSD, 3.827% for PDZ, and 3.542% for VDZ. Intersession CVW from the glaucoma group (n = 45) was 1.412% for VAD, 1.132% for VSD, 3.915% for PDZ, and 3.654% for VDZ. Non-glaucomatous intrasession ICC ranged from 0.711 to 0.824, non-glaucomatous intersession ICC ranged from 0.649 to 0.762, glaucomatous intrasession ICC ranged from 0.710 to 0.853, and glaucomatous intersession ICC ranged from 0.661 to 0.827. Conclusions Macular OCTA scans can be a useful tool in monitoring the longitudinal progression of glaucoma due to their high repeatability and reproducibility.

Differences in Mean Values and Variance in Quantitative Analyses of Foveal OCTA Imaging.

Multiple approaches for quantifying parameters such as vessel density (VD) and vessel length density (VLD) in optical coherence tomography angiography (OCTA) en-face segmentations are currently available. While it is common knowledge that data gathered from different methods should not be directly compared to each other, a comparison of the different methods can help to further the understanding of differences between different methods of measurement. Here we compare a common method of semiautomatically quantifying VD and VLD with an automated method supplied by the manufacturer of an OCTA device and report on differences in performance in order to probe for and highlight differences in values gathered by both methods. OCTA was performed using the swept source PLEX Elite 9000 device, software version 2.0.1.47652 (Carl Zeiss Meditec Inc., Dublin, CA, USA). Scans of 3 mm × 3 mm from healthy volunteers centred on the fovea were acquired by a well-trained certified ophthalmologist. Scans with a signal strength of 8 out of 10 or higher were included. Quantitative parameters of the 3 mm × 3 mm cube scans were automatically generated and segmented into superficial capillary plexus (SCP) and deep capillary plexus (DCP) layers using layer segmentation produced by the instrument software and prototype analysis VD quantification software (Macular Density v.0.7.1, ARI Network Hub, Carl Zeiss Meditec Inc., Dublin, CA, USA) supplied by the manufacturer. An alternative approach of quantitative analysis of VD and VLD was performed manually with ImageJ (National Institutes of Health, Bethesda, Maryland, USA), as previously reported. VD was assessed as the ratio of the retinal area occupied by vessels. VDL was measured as the total length of the skeletonised vessels using 1-pixel centre line extraction of the blood vessels. We report differences in standard deviation (SD) in OCTA parameters obtained using different methods. The standard deviation of VD and VLD measurements was statistically significantly different in VD of 3 mm × 3 mm DCP (p = 0.009), VLD of 3 mm × 3 mm SCP (p = 0.000), and VLD of 3 mm × 3 mm DCP (p = 0.021). No statistically significant differences were found in VD of 3 mm × 3 mm SCP (p = 0.128) or VLD of 3 mm × 3 mm SCP (p = 0.107). As expected, we were able to demonstrate significant differences in quantitative OCTA parameters gathered from the same images using different methods of quantification. Values gathered using different methods are not interchangeable. In scientific studies and in situations where long-term follow-up is necessary, the same device and the same method of quantification should be used to maintain retrospective comparability of measurements.

Impact of accelerated washout of Technetium-99m-sestamibi on exercise tolerance in patients with acute coronary syndrome: single-center experience.

Technetium-99m-sestamibi (99mTc-sestamibi) single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with acute coronary syndrome (ACS) could be used to assess area-at-risks, as well as myocardial infarct or saved sizes. In patients with ACS, accelerated washout of 99mTc-sestamibi during early and delayed imaging in the acute phase may suggest mitochondrial dysfunction in the injured but salvaged myocardium. However, the link between 99mTc-sestamibi accelerated washout and exercise tolerance is unknown. The purpose of this study was to investigate a possible association between 99mTc-sestamibi accelerated washout and exercise tolerance in acute ACS patients as they progressed into the chronic phase. One hundred and sixty-five patients with ACS who underwent 99mTc-sestamibi SPECT MPI during the acute phase were recruited. On this basis, we calculated the total perfusion deficits (TPDs) for early (1h after tracer injection) and delayed (4h after tracer injection) images using automated quantification software. We then subtracted the early TPDs from the delayed TPDs to calculate the ΔTPD. We conducted a cardiopulmonary exercise test in acute and chronic phases. We divided two groups according to the median ΔTPD (the ΔTPD ≥ 4 group and the ΔTPD < 4 group) and compared anaerobic threshold (AT; ml/kg/min) between the groups. For anaerobic threshold (AT) improvement in data analysis, we employed multivariate logistic regression analysis. A total of 101 ST-segment elevation myocardial infarctions, 36 non-ST-elevation myocardial infarctions, and 28 unstable angina pectoris events were reported as ACS. From acute phase (10.8 ± 4.2 ml/kg/min) to chronic phase (11.9 ± 2.3 ml/kg/min), the AT in the ΔTPD ≥ 4 group was significantly increased (p < 0.0001). This trend was also seen in the ΔTPD < 4 group from acute (11.4 ± 1.8 ml/kg/min) to chronic phase (12.1 ± 2.2 ml/kg/min, p = 0.015). AT was lower in the ΔTPD ≥ 4 group in the acute phase (p = 0.027), but there was no difference in AT between the two groups in the chronic phase (p = 0.60). ΔTPD and the absence of diabetes were both independent predictors of AT improvement in multivariate logistic regression analysis. Receiver-operating characteristic curve analysis determined that ΔTPD = 6 was the best cut-off value, with 60.0% sensitivity and 71.4% specificity, respectively. The accelerated washout of 99mTc-sestamibi in patients with ACS during the acute phase could help to predict improvement in exercise tolerance in the chronic phase.

LC-MS/MS-Based Serum Protein Profiling for Identification of Candidate Biomarkers in Pakistani Rheumatoid Arthritis Patients.

Rheumatoid arthritis is an autoimmune disorder of complex disease etiology. Currently available serological diagnostic markers lack in terms of sensitivity and specificity and thus additional biomarkers are warranted for early disease diagnosis and management. We aimed to screen and compare serum proteome profiles of rheumatoid arthritis serotypes with healthy controls in the Pakistani population for identification of potential disease biomarkers. Serum samples from rheumatoid arthritis patients and healthy controls were enriched for low abundance proteins using ProteoMinerTM columns. Rheumatoid arthritis patients were assigned to one of the four serotypes based on anti-citrullinated peptide antibodies and rheumatoid factor. Serum protein profiles were analyzed via liquid chromatography-tandem mass spectrometry. The changes in the protein abundances were determined using label-free quantification software ProgenesisQITM followed by pathway analysis. Findings were validated in an independent cohort of patients and healthy controls using an enzyme-linked immunosorbent assay. A total of 213 proteins were identified. Comparative analysis of all groups (false discovery rate < 0.05, >2-fold change, and identified with ≥2 unique peptides) identified ten proteins that were differentially expressed between rheumatoid arthritis serotypes and healthy controls including pregnancy zone protein, selenoprotein P, C4b-binding protein beta chain, apolipoprotein M, N-acetylmuramoyl-L-alanine amidase, catalytic chain, oncoprotein-induced transcript 3 protein, Carboxypeptidase N subunit 2, Apolipoprotein C-I and Apolipoprotein C-III. Pathway analysis predicted inhibition of liver X receptor/retinoid X receptor activation pathway and production of nitric oxide and reactive oxygen species pathway in macrophages in all serotypes. A catalogue of potential serum biomarkers for rheumatoid arthritis were identified. These biomarkers can be further evaluated in larger cohorts from different populations for their diagnostic and prognostic potential.

New 3-Dimensional Volumetric Ultrasound Method for Accurate Quantification of Atherosclerotic Plaque Volume

BackgroundCarotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)–matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging. ObjectivesThis study aimed to validate this method for plaque volume measurement in early and intermediate–advanced plaques in the carotid and femoral territories. MethodsPlaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate–high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)–based plaque quantification software. ResultsIn the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 μL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 μL-859 μL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%. Conclusions3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate–advanced plaques located in carotid and femoral arteries.

An automated software for real-time quantification of wall shear stress distribution in quantitative coronary angiography data

BackgroundWall shear stress (WSS) estimated in 3D-quantitative coronary angiography (QCA) models appears to provide useful prognostic information and identifies high-risk patients and lesions. However, conventional computational fluid dynamics (CFD) analysis is cumbersome limiting its application in the clinical arena. This report introduces a user-friendly software that allows real-time WSS computation and examines its reproducibility and accuracy in assessing WSS distribution against conventional CFD analysis. MethodsFrom a registry of 414 patients with borderline negative fractional flow reserve (0.81–0.85), 100 lesions were randomly selected. 3D-QCA and CFD analysis were performed using the conventional approach and the novel CAAS Workstation WSS software, and QCA as well as WSS estimations of the two approaches were compared. The reproducibility of the two methodologies was evaluated in a subgroup of 50 lesions. ResultsA good agreement was noted between the conventional approach and the novel software for 3D-QCA metrics (ICC range: 0.73–0-93) and maximum WSS at the lesion site (ICC: 0.88). Both methodologies had a high reproducibility in assessing lesion severity (ICC range: 0.83–0.97 for the conventional approach; 0.84–0.96 for the CAAS Workstation WSS software) and WSS distribution (ICC: 0.85–0.89 and 0.83–0.87, respectively). Simulation time was significantly shorter using the CAAS Workstation WSS software compared to the conventional approach (4.13 ± 0.59 min vs 23.14 ± 2.56 min, p < 0.001). ConclusionCAAS Workstation WSS software is fast, reproducible, and accurate in assessing WSS distribution. Therefore, this software is expected to enable the broad use of WSS metrics in the clinical arena to identify high-risk lesions and vulnerable patients.

Assessment and validation of a novel fast fully automated artificial intelligence left ventricular ejection fraction quantification software.

Quantification of left ventricular ejection fraction (LVEF) by transthoracic echocardiography (TTE) is operator-dependent, time-consuming, and error-prone. LVivoEF by DIA is a new artificial intelligence (AI) software, which displays the tracking of endocardial borders and rapidly quantifies LVEF. We sought to assess the accuracy of LVivoEF compared to cardiac magnetic resonance imaging (cMRI) as the reference standard and to compare LVivoEF to the standard-of-care physician-measured LVEF (MD-EF) including studies with ultrasound enhancing agents (UEAs). In 273 consecutive patients, we compared MD-EF and AI-derived LVEF to cMRI. AI-derived LVEF was obtained from a non-UEA four-chamber view without manual correction. Thirty-one patients were excluded: 25 had interval interventions or incomplete TTE or cMRI studies and six had uninterpretable non-UEA apical views. In the 242 subjects, the correlation between AI and cMRI was r=.890, similar to MD-EF and cMRI with r=.891 (p=0.48). Of the 126 studies performed with UEAs, the correlation of AI using the unenhanced four-chamber view was r=.89, similar to MD-EF with r=.90. In the 116 unenhanced studies, AI correlation was r=.87, similar to MD-EF with r=.84. From Bland-Altman analysis, LVivoEF underreported the LVEF with a bias of 3.63 ± 7.40% EF points compared to cMRI while MD-EF to cMRI had a bias of .33 ± 7.52% (p=0.80). Compared to cMRI, LVivoEF can accurately quantify LVEF from a standard apical four-chamber view without manual correction. Thus, LVivoEF has the ability to improve and expedite LVEF quantification.