Agreement Kappa Research Articles

Accuracy of the LaserSAFE technique for detecting positive surgical margins during robot-assisted radical prostatectomy: blind assessment and inter-rater agreement analysis.

Fluorescence confocal microscopy (FCM) is a new imaging modality capable of generating digital microscopic resolution scans of fresh surgical specimens, and holds potential as an alternative to frozen section (FS) analysis for intra-operative assessment of surgical margins. Previously, we described the LaserSAFE technique as an application of FCM for margin assessment in robot-assisted radical prostatectomy (RARP) using the Histolog® scanner. This study describes the accuracy and inter-rater agreement of FCM imaging compared to corresponding paraffin-embedded analysis (PA) among four blinded pathologists for the presence of positive surgical margins (PSM). RARP specimens from patients enrolled in the control arm of the NeuroSAFE PROOF study (NCT03317990) were analysed from April 2022 to February 2023. Prostate specimens were imaged using the Histolog® scanner before formalin fixation and PA. Four trained assessors, blinded to PA, reviewed and analysed FCM images of the posterolateral prostatic surface. A total of 31 prostate specimens were included in the study. PA per lateral side of the prostate identified 11 instances of positive margins. Among the four histopathologists included in our study, FCM achieved a sensitivity of 73-91 and specificity of 94-100% for the presence of PSM. Fleiss' Kappa for inter-rater agreement on PSM was 0.78 (95% confidence interval = 0.64-0.92), indicating substantial agreement. This blinded analysis of FCM versus PA among histopathologists with different experience levels demonstrated high accuracy and substantial inter-rater agreement for diagnosing PSM. This supports the role of the FCM as an alternative to FS.

Assessing Alkaline Phosphatase Reference Intervals Using Gamma-Glutamyl Transferase as a Surrogate for Normal Liver Function

Abstract Limited studies assess reference intervals (RIs) for hepatic enzymes, particularly for alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT). In the US, ALP and GGT RIs were established on Roche assays using a European cohort of ≤ 450 patients that may not reflect population variance. Further, age- and sex-specific variation in ALP and GGT may warrant tiered RIs, but evidence to justify this approach is limited. We aimed to evaluate the manufacturer’s RIs by comparing them to indirectly estimated RIs (IRIs). 217,333 AST, ALT, ALP, and GGT results (Roche c702) performed between 1/1/2019-12/31/2022 on outpatients ≥21 years were extracted from the laboratory information system. The first ALP for each patient was identified, and the earliest AST, ALT, and GGT drawn within 7 days was included. This approach was repeated for GGT. Concordance and correlation were calculated using Weighted Cohen’s Kappa and Spearman’s rank correlation coefficient respectively. {refineR} was applied to patients with “normal” liver function (defined as normal AST, ALT for all IRIs, plus normal GGT for ALP IRIs, and ALP for GGT IRIs). IRIs were estimated for all males, all females, females ≤50, and females >50 years and compared to the method specific manufacturer RI (ALP: 40-129 Units/L for males and 35-104 Units/L for females; GGT: 8-61 Units/L for males and 5-36 Units/L for females). Of the 71,783 outpatients, 54.9% were female, 74% self-identified as white and 19% as black. The median age was 58 (IQR: 43-68 years), the median ALP concentration was 77 (62-97 Units/L), and the median GGT concentration was 28 (17-57 Units/L). A moderate agreement (Kappa = 0.48, 95% confidence interval: 0.46-0.51) and positive correlation (r = 0.51; p<0.0001) between ALP and GGT was observed. For ALP and GGT, no significant differences were observed between the lower limit of the IRIs and the current RI. The upper limit of estimated IRIs was 132 [95% confidence interval: 117-147 Units/L] for patients with normal AST/ALT/GGT (n = 1596). For males, the sex-specific upper limit was 120 [101-140 Units/L] and for females, was 123 [110-136 Units/L]. Age stratified upper limits for females were 120 [101-140 Units/L], and 109 [97-121 Units/L] for ≤50 and >50 years, respectively. The upper limit for all patients with normal AST/ALT/ALP (n = 2,446) was 62 [55-70 Units/L]. For males, all females, females ≤50 and >50 years was 58 [46-69 Units/L], 40 [39-51 Units/L], 31 [23-39 Units/L], and 56 [41-71 Units/L]. Manufacturer RIs agreed well with the IRIs for most subsets, but differed for ALP IRIs of all females with normal hepatobilliary function and in GGT for all females and females >50 years. Further investigation of the impact of preselecting patient populations on IRIs and a direct RI study on select patient subsets is worth investigation.

Assessing the feasibility of ChatGPT-4o and Claude 3-Opus in thyroid nodule classification based on ultrasound images.

Large language models (LLMs) are pivotal in artificial intelligence, demonstrating advanced capabilities in natural language understanding and multimodal interactions, with significant potential in medical applications. This study explores the feasibility and efficacy of LLMs, specifically ChatGPT-4o and Claude 3-Opus, in classifying thyroid nodules using ultrasound images. This study included 112 patients with a total of 116 thyroid nodules, comprising 75 benign and 41 malignant cases. Ultrasound images of these nodules were analyzed using ChatGPT-4o and Claude 3-Opus to diagnose the benign or malignant nature of the nodules. An independent evaluation by a junior radiologist was also conducted. Diagnostic performance was assessed using Cohen's Kappa and receiver operating characteristic (ROC) curve analysis, referencing pathological diagnoses. ChatGPT-4o demonstrated poor agreement with pathological results (Kappa = 0.116), while Claude 3-Opus showed even lower agreement (Kappa = 0.034). The junior radiologist exhibited moderate agreement (Kappa = 0.450). ChatGPT-4o achieved an area under the ROC curve (AUC) of 57.0% (95% CI: 48.6-65.5%), slightly outperforming Claude 3-Opus (AUC of 52.0%, 95% CI: 43.2-60.9%). In contrast, the junior radiologist achieved a significantly higher AUC of 72.4% (95% CI: 63.7-81.1%). The unnecessary biopsy rates were 41.4% for ChatGPT-4o, 43.1% for Claude 3-Opus, and 12.1% for the junior radiologist. While LLMs such as ChatGPT-4o and Claude 3-Opus show promise for future applications in medical imaging, their current use in clinical diagnostics should be approached cautiously due to their limited accuracy.

Micro-enema immediately prior to prostate MRI: effects on rectal gas, image quality and PI-QUAL score.

Our aim was to determine whether the administration of a micro-enema immediately prior to prostate MRI is associated with a reduction in rectal gas, gas related artifacts and an improvement in image quality and PI-QUAL score. This retrospective analysis enrolled 171 patients who underwent multiparametric 3T prostate MRI at our institution between January 2021 and September 2022. 86 patients received a micro-enema, and a further 85 patients did not. Two fellowship trained abdominal radiologists were blinded and independently reviewed each prostate MRI, recording scores on a dedicated scoring sheet. The quality of T2 weighted (T2W), diffusion weighted (DWI), and dynamic contrast enhancement (DCE) images were assessed according to standardised scales supported in the literature. In addition, gas related artifacts and rectal gas level were examined. An independent-samples Mann-Whitney U and t-test were performed, comparing both the median and mean score between micro-enema and no micro-enema groups for each reader. Spearman's correlation was used to determine the strength of relationship between variables. A quadratic weighted Cohen's Kappa and percent agreement were used to assess inter-observer agreement. Image quality was improved in those who received the micro-enema compared to those who did not according to the visual grading scale on the DWI sequence for both readers (reader 1: median 4 vs. 4, p < 0.001, mean 4.27 vs. 3.92, p < 0.001; reader 2: median 5 vs. 4, p < 0.001, mean 4.74 vs. 4.14, p < 0.001). PI-QUAL score was significantly improved in the micro-enema group for reader 2 only (reader 1: median 4 vs. 4, p = 0.25, mean 3.99 vs. 4.08, p = 0.21; reader 2: median 5 vs. 5, p = 0.01, mean 4.95 vs. 4.78, p = 0.01). Visual grading score for both the T2W and DCE images was not significantly different. Rectal gas level was lower in patients who received the micro-enema for both readers (reader 1: median 2 vs. 4, p < 0.001, mean 2.12 vs. 3.60, p < 0.001; reader 2: median 1 vs. 2, p < 0.001, mean 1.37 vs. 2.48, p < 0.001), correlating with a lower score for gas-related artifacts (reader 1: median 1 vs. 2, p < 0.001, mean 1.50 vs. 1.92, p < 0.001; reader 2: median 1 vs. 1, p < 0.001, mean 1.16 vs. 1.71, p < 0.001) in this group. Correlation between rectal gas level and gas-related artifacts on DWI regardless of whether a micro-enema was given was strong (rs = 0.71, p < 0.001). Correlation was moderate to strong between rectal gas level and image quality on DWI (rs = -0.63, p < 0.001). There was only 1 (1.2%) borderline diagnostic or non-diagnostic DWI sequence in those who received the micro-enema, compared to 9 (10.6%) in those who did not (p = 0.009). Interobserver agreement was moderate for image quality on DWI, gas related artifacts and rectal gas level (weighted kappa values of 0.52, 0.49 and 0.53 respectively). The administration of a micro-enema immediately prior to prostate MRI is associated with a significant improvement in image quality on the DWI sequence compared to no bowel preparation. This is mediated through a reduction in rectal gas and gas related artifacts. Improvements in PI-QUAL score was mixed between readers.

Anti-SARS-CoV-2 IgM Antibody Levels Measured by an In-House ELISA in a Convalescent Latin Population Persist over Time and Exhibit Neutralizing Capacity to Several Variants of Concern.

The coronavirus, SARS-CoV-2, is the causative agent for COVID-19, first registered in Wuhan, China and responsible for more than 6 million deaths worldwide. Currently, RT-PCR is the gold-standard method for diagnosing COVID-19. However, serological tests are needed for screening acute disease diagnosis and screening large populations during the COVID-19 outbreak. Herein, we described the development and validation of an in-house enzyme-linked immunosorbent assay (ELISA) for detecting the levels of anti-spike-1-RBD IgM antibody (CovIgM-ELISA) in well-defined serum/plasma panel for screening and identifying subjects infected with SARS-CoV-2 in a Latin population. In-house CovIgM-ELISA has the format of an indirect ELISA. It was optimized by checkerboard titration using recombinant SARS-CoV-2 spike-S1-RBD protein as an antigen. We found that, compared to the RT-PCR as the standard method, the in-house CovIgM-ELISA displayed sensitivities of 96.15% and 93.22% for samples collected up to 30 or 60 days after infection, respectively, as well as 95.59% specificity with 97.3% accuracy. The agreement kappa value (κ) of our CovIgM-ELISA was substantial when compared to RT-PCR (κ = 0.873) and the anti-SARS-CoV-2 IgM ELISA (InBios Int) (κ = 0.684). The IgM levels detected in the population positively correlated with the neutralizing activity against the wild-type, Alpha and Delta variants of concern, but failed to neutralize Omicron. These data indicate that our in-house CovIgM-ELISA is a compatible performing assay for the detection of SARS-CoV-2 infection.

B-207 Clinical Evaluation of ExiStation™ FA 96 RV for the detection of human respiratory viruses in human nasopharyngeal swab specimen

Abstract Background There has been growing demand for fully automated multiplex testing of respiratory viruses in molecular diagnostics following the COVID-19 pandemic. ExiStation™ FA 96 RV developed by BIONEER is a multiplex real-time RT-PCR assay. It is designed for the simultaneous detection and differentiation of SARS-CoV-2, Influenza A, Influenza B, and RSV RNA in human nasopharyngeal swab specimens from individuals showing signs and symptoms of respiratory viral infection. ExiStation™ FA 96 automates the entire process from RNA extraction to real-time RT-PCR for up to 96 samples at once within 100 minutes. Moreover, the system is equipped to decap sample tubes, eliminating the need for handling sample transport media. In this study, the clinical performance of the ExiStation™ FA 96 RV assay was evaluated using nasopharyngeal swab samples. Methods Nasopharyngeal swab samples, totaling 859 samples, are collected according to the procedures by the clinical institution in France and preserved in Virus transport media. Once anonymized and randomly allocated, the swab transport media tube, without capping procedure, are directly placed onto the ExiStation™ FA 96. Subsequently, both extraction and real-time RT-PCR are automatically processed. Clinical sensitivity, specificity, and agreement are analyzed by comparing results with confirmatory reagents SARS-CoV-2 RT-qPCR Reagent Kit, PKAmp™ Respiratory SARS-CoV-2 RT-PCR Panel Kit, and Bosphore SARS-CoV-2/Flu/RSV Panel Kit, as well as comparator reagent Allplex™ Respiratory Panel 1 and Allplex™ SARS-CoV-2 Assay. Results The comparison between confirmatory reagents and the ExiStation™ FA 96 RV resulted in a clinical sensitivity of at least 96.4% (164/164 for SARS-CoV-2, 64/65 for Influenza A, 74/75 for Influenza B, and 53/55 for RSV) and a clinical specificity of 100% (500/500 for all targets). When compared with the comparator reagent, the overall agreement and Cohen's kappa value were both determined to be above 99.1% and 0.989, respectively (664/664 for SARS-CoV-2, 564/565 for Influenza A, 573/575 for Influenza B, and 550/555 for RSV). Additionally, any discrepant samples identified in comparison with the comparator reagent were verified through sequencing analysis. Upon sequencing analysis on a total of 8 samples and aligning the confirmed results with the analysis content, no alterations observed in the analysis of clinical sensitivity and specificity. Conclusions The evaluation of the ExiStation™ FA 96 RV assay showed outstanding clinical performance in detecting four respiratory viruses, SARS-CoV-2, Influenza A, Influenza B, and RSV, with high sensitivity and specificity. This study supports that the ExiStation™ FA 96 RV assay is a reliable tool for simultaneous molecular diagnostics of various respiratory infections in clinical laboratories.

A-185 Impact Assessment of Centrifugation During Transportation on Examination Results

Abstract Background Laboratories are increasingly challenged to seek solutions to expedite the collection process and provide more convenience to patients. This study aims to validate the centrifugation of samples in transport cars for home collections without need to return to the basic unit after each sample collection for centrifugation using the traditional method for up to 2 hours, as recommended in the literature, providing an increase in the number of patient appointments and a greater portfolio of exams. Methods The study was carried out evaluating measurands that represent different methodologies and sample stability challenges, namely, PTH, free T4, testosterone, CA19.9, anti-HBS, anti-transglutaminase, LDH, potassium, glucose, sodium and alkaline phosphatase( FAL). The centrifuge used during sample transport was the Drucker, model Horizon - 6 Flex, calibrated and monitored during the study. Forty samples from volunteer patients were analyzed, with one tube centrifuged in the equipment installed in the car and a second tube in the basic unit's centrifuge within 2 hours of collection, both respecting the 30-minute clot retraction period. All tubes were sent to the same laboratory for execution. Results Throughout the study period, the calibration of the car's centrifuge remained stable. In the correlation, the variance, calculated by the F Test, showed an adequate result, below 1.69. The difference between the means of the test method and the comparative method calculated through the T Test was below the Critical T. The Pearson correlation for the mensurands Free T4, CA19.9, anti-transglutaminase, LDH, potassium, sodium and glucose was lower than the accepted limit of 0.950. Agreement analysis and Kappa index were performed and the data were evaluated from a qualitative point of view by the medical team, who considered the differences to have no clinical impact on the patient. PTH, CA19.9 and FAL were approved by the difference graph.In relation to glucose, the correlation between the serum-gel tube and fluoride was also evaluated, where we obtained lower results with the fluoride tube due to hemolysis caused by the additive. During the analysis of LDH results, a tendency to decrease the concentration of its dosages over time can be observed, and in this case there were lower results in samples centrifuged in the basic unit, due to the longer interval between collection and centrifugation. Conclusions After evaluation from a pre-analytical, quality and medical point of view, centrifugation from home samples collection directly in the car will allow a greater number of patients to be served, as there will be no need to return to the basic unit for centrifugation every 2 hours. It will also bring greater safety in centrifuging the sample at the correct time, avoiding any delays that may occur, mitigating potential deviations in results and greater process efficiency as the collector will not need to return to the basic unit for centrifugation, right during During the collection route, the samples will already be prepared for sending directly to the execution site. For glucose and LDH tests, it was possible to observe efficiency gains due to centrifugation 30 minutes after collection.

Evaluation of Molecular Assays for Diagnosis of Amoebic Liver Abscess in India with Bayesian Latent Class Analysis.

Amoebic liver abscess (ALA) is the most common extra-intestinal complication of Entamoeba histolytica, accounting for 50,000 deaths annually, and is endemic in South Asia. Diagnosis based on microscopic examination is insensitive, and serological assays are not discerning of current infections in endemic settings with high exposure. For a rapid and confirmatory laboratory diagnosis of ALA, the performance of a polymerase chain reaction (PCR), quantitative real time PCR (qPCR), digital droplet PCR (ddPCR), and a loop-mediated isothermal amplification (LAMP) assay that detects E. histolytica DNA in liver abscess pus, and a lectin antigen detection ELISA were evaluated against clinical diagnosis (based on predefined criteria) as the gold standard. Owing to the lack of a laboratory gold standard, a Bayesian latent class analysis approach was also used to determine sensitivity and specificity of these assays. In the latent class analysis, qPCR and ddPCR showed the highest sensitivity (98% and 98.1%) and specificity (both 96.6%), and although clinical diagnosis had a comparable sensitivity to qPCR and ddPCR (95.2%), poorer specificity (64.3%) was seen. Kappa agreement analysis showed that qPCR and ddPCR had a perfect agreement of 1 followed by an agreement of 0.76 (95% CI: 0.64-0.88) with PCR. Considering the performance characteristics and relative ease of setting up qPCR as well as the wide availability of qPCR equipment needed, this would be the most optimal assay for rapid, confirmatory, molecular diagnosis of ALA in the tertiary care laboratory setting in India, whereas further optimization of LAMP or antibody-based detection is required for use at smaller or secondary hospitals.

Computed tomography scan accuracy for the prediction of lobe and division of liver tumors by four board-certified radiologists.

(1) Evaluate the accuracy of computed tomography (CT) scans for localization of liver masses. (2) Assess the agreement between radiologists on localization. (3) Determine if location influences the accuracy of localization and histopathologic diagnosis. (4) Determine what lobar vasculature radiologists found most useful for localization. Retrospective. A total of 67 client-owned dogs with a total of 75 hepatic masses. Records were reviewed for relevant data. Localization for each hepatic mass was performed by four radiologists (JH, EH, ML, JF) independently. Overall accuracy of mass localization was 217/292 (74.3%) by lobe and 264/300 (88%) by division. Accuracy for the quadrate lobe (11/27, 40.7%) was lower (p < .05) than for the caudate process of the caudate lobe (19/24, 79.2%), left medial lobe (47/64, 73.4%) and left lateral lobe (95/101, 89.6%). Accuracy for the right lateral lobe (17/35, 48.6%) was lower (p < .05) lower than for the left lateral lobe (95/101, 89.6%). Accuracy of localization was 173/192 (90.1%) for masses located in the left division, 37/48 (77.1%) in the central division, and 53/60 (88.3%) for the right division. The agreement (kappa) between radiologists was good (0.61-0.8) to excellent (0.81-1) for division and moderate (0.41-0.6) to good for lobe localization. CT localization was more accurate for division than lobe localization of canine hepatic masses. Similarly, radiologists had a better agreement for division than lobe localization. This study supports CT as a useful modality for liver mass localization based on division. CT localization to specific lobes should be interpreted with some caution.

Predictive modeling of sensory responses in deep brain stimulation.

Although stimulation-induced sensations are typically considered undesirable side effects in clinical DBS therapy, there are emerging scenarios, such as computer-brain interface applications, where these sensations may be intentionally created. The selection of stimulation parameters, whether to avoid or induce sensations, is a challenging task due to the vast parameter space involved. This study aims to streamline DBS parameter selection by employing a machine learning model to predict the occurrence and somatic location of paresthesias in response to thalamic DBS. We used a dataset comprising 3,359 paresthetic sensations collected from 18 thalamic DBS leads from 10 individuals in two clinical centers. For each stimulation, we modeled the Volume of Tissue Activation (VTA). We then used the stimulation parameters and the VTA information to train a machine learning model to predict the occurrence of sensations and their corresponding somatic areas. Our results show fair to substantial agreement with ground truth in predicting the presence and somatic location of DBS-evoked paresthesias, with Kappa values ranging from 0.31 to 0.72. We observed comparable performance in predicting the presence of paresthesias for both seen and unseen cases (Kappa 0.72 vs. 0.60). However, Kappa agreement for predicting specific somatic locations was significantly lower for unseen cases (0.53 vs. 0.31). The results suggest that machine learning can potentially be used to optimize DBS parameter selection, leading to faster and more efficient postoperative management. Outcome predictions may be used to guide clinical DBS programming or tuning of DBS based computer-brain interfaces.

Phenotypic variations in knee osteoarthritis: insights from MRI and radiographic comparisons.

To investigate the correlation between MRI-based phenotypes (cartilage-meniscus, subchondral bone, and inflammatory) and radiography-based atrophic and hypertrophic phenotypes, aiming to demonstrate MRI's diagnostic capability in identifying complex osteoarthritis phenotypes that radiography cannot fully capture. This single-center retrospective study examined knee radiographs and MRIs of patients from November 2021 to April 2023 to identify osteoarthritis phenotypes. Radiographs were staged by the Kellgren-Lawrence system, and both modalities were classified into atrophic or hypertrophic phenotypes. MRIs were further classified into three phenotypes: cartilage-meniscus, subchondral bone, and inflammatory. Associations between phenotypes, Kellgren-Lawrence stage, age, and gender were analyzed with Pearson chi-square test and student T-test. Reliability measurements were evaluated using kappa statistic. A total of 214 knees from 187 individuals (73.3% women, 26.7% men; mean age 57.1 ± 9.1years) were included. The hypertrophic MRI phenotype was significantly associated with cartilage-meniscus and subchondral bone phenotypes (p < 0.001). Cartilage-meniscus and subchondral bone phenotypes were less prevalent in Kellgren-Lawrence stage 2 than in stages 3 and 4 (p < 0.001 and p = 0.004, respectively). The subchondral bone phenotype was more common in men (p = 0.022), and the cartilage-meniscus phenotype in the elderly (p < 0.001). Radiography and MRI had substantial agreement (Kappa = 0.637, p < 0.001) in diagnosing hypertrophic and atrophic phenotypes. The hypertrophic phenotype was associated with cartilage-meniscus and subchondral bone phenotypes, with lower prevalences in Kellgren-Lawrence stage 2 knees. MRI offers enhanced phenotypic characterization, which facilitates more precise and individualized management in osteoarthritis care. Despite limitations compared to MRI, radiography remains valuable for the evaluation of hypertrophic and atrophic phenotypes.

Antigenic reactivity of Leishmania (Viannia) lainsoni axenic amastigote proved to be a suitable alternative for optimizing Montenegro skin test

BackgroundLaboratory diagnosis of American cutaneous leishmaniasis (ACL) requires a tool amenable to the epidemiological status of ACL in Brazil. Montenegro skin test (MST), an efficient immunological tool used for laboratory diagnosis of ACL, induces delayed-type hypersensitivity (DTH) response to the promastigote antigens of Leishmania; however, human immune responses against infection are modulated by the amastigote of the parasite. Leishmania (V.) lainsoni induces strong cellular immunity in humans; therefore, the antigenic reactivity of its axenic amastigote (AMA antigen) to MST was evaluated for the laboratory diagnosis of ACL.MethodsAmong 70 individuals examined, 60 had a laboratory-confirmed diagnosis of ACL; 53 had localized cutaneous leishmaniasis (LCL), and 7 had mucosal leishmaniasis (ML). Patients were treated at the Evandro Chagas Institute’s leishmaniasis clinic, Pará State, Brazil. Ten healthy individuals with no history of ACL (control group) were also examined. Leishmania (V.) braziliensis promastigote antigen (PRO) was used to compare the reactivity with that of AMA antigen. Paired Student’s t-test, kappa agreement, and Spearman test were used to evaluate the reactivity of AMA and PRO.ResultsThe mean reactivity of AMA in ACL patients was 19.4 mm ± 13.3, which was higher (P < 0.001) than that of PRO: 12.1 mm ± 8.1. MST reactivity according to the clinical forms revealed that AMA reactivity in LCL and ML, 18.8 mm ± 13.3 and 24.3 mm ± 13.7, was higher (P < 0.001) than that of PRO, 11.8 mm ± 8.2 and 14.6 mm ± 8.4, respectively.ConclusionAMA reactivity was higher than that of PRO, indicating that AMA is a promising alternative for optimizing MST in the laboratory diagnosis of ACL.Graphical abstract

Reliability of the Assessment of Tooth Wear Severity on Dental Hard Tissues and Dental Restorations, Using the TWES 2.0, by Nonexperts.

Tooth wear is a multifactorial process resulting in the loss of dental hard tissues. For its assessment, the tooth wear evaluation system (TWES) 2.0 has been published. Previous studies on the TWES involved well-trained practitioners, rather than nonexperts. The first aim of this study was to investigate the reliability of the assessment of tooth wear severity on dental hard tissues, using the TWES 2.0, by nonexperts. The second aim was to investigate the reliability of assessment of wear severity on dental restorations, using a third scale. Forty-seven dental students evaluated at least 9 of 14 possible patient cases on dental casts and intraoral photographs. Cohen's kappa (agreement with sample solution) and Fleiss' kappa (Inter-rater reliability) were calculated. The agreements of the operators' ratings compared to the sample-solution resulted in Cohen's kappa between 0.02 and 0.9. The agreements were 0.34 for occlusal; 0.43 for vestibular; 0.57 for oral surfaces. Inter-rater reliability (Fleiss' kappa) was 0.35 for occlusal, 0.17 for vestibular and 0.24 for oral assessment. The inter-rater reliability of the ratings on tooth surfaces with restorations was lower with 0.21 (occlusal), 0.14 (vestibular) and 0.39 (oral). The agreement on different restorations differed tremendously. The ability to correctly assess the cases varied considerably between individual examiners. Within the limits of this study, assessment of restorations was slightly more challenging compared to natural teeth, particularly in occlusal regions or when the restorative material is gold. Subsequent studies should address whether enhanced training and improved definition of tooth wear grades result in higher reliability scores.

Evaluation of automated pediatric sleep stage classification using U-Sleep: a convolutional neural network.

U-Sleep is a publicly available automated sleep stager, but has not been independently validated using pediatric data. We aimed to a) test the hypothesis that U-Sleep performance is equivalent to trained humans, using a concordance dataset of 50 pediatric polysomnogram excerpts scored by multiple trained scorers, and b) identify clinical and demographic characteristics that impact U-Sleep accuracy, using a clinical dataset of 3114 polysomnograms from a tertiary center. Agreement between U-Sleep and 'gold' 30-second epoch sleep staging was determined across both datasets. Utilizing the concordance dataset, the hypothesis of equivalence between human scorers and U-Sleep was tested using a Wilcoxon two one-sided test (TOST). Multivariable regression and generalized additive modelling were used on the clinical dataset to estimate the effects of age, comorbidities and polysomnographic findings on U-Sleep performance. The median (interquartile range) Cohen's kappa agreement of U-Sleep and individual trained humans relative to "gold" scoring for 5-stage sleep staging in the concordance dataset were similar, kappa=0.79 (0.19) vs 0.78 (0.13) respectively, and satisfied statistical equivalence (TOST p < 0.01). Median (interquartile range) kappa agreement between U-Sleep 2.0 and clinical sleep-staging was kappa=0.69 (0.22). Modelling indicated lower performance for children < 2 years, those with medical comorbidities possibly altering sleep electroencephalography (kappa reduction=0.07-0.15) and those with decreased sleep efficiency or sleep-disordered breathing (kappa reduction=0.1). While U-Sleep algorithms showed statistically equivalent performance to trained scorers, accuracy was lower in children < 2 years and those with sleep-disordered breathing or comorbidities affecting electroencephalography. U-Sleep is suitable for pediatric clinical utilization provided automated staging is followed by expert clinician review.

Indirect ELISAs with sucrose subcellular fractions of Neospora caninum as antigens for diagnosis of neosporosis in cattle

Neosporosis is one of the major causes of abortion in cattle, and it is responsible for significant economic losses in those animals. Thus, this study aimed to evaluate indirect ELISA using subcellular fractions of Neospora caninum obtained via sucrose gradient separation. Eighty-five sera from dairy cattle previously tested using indirect immunofluorescence assay (IFA) were used. Three distinct bands were separated at 1.0 M, 1.4 M, 1.6 M, and the pellet at 1.8 M, which were identified as fractions one (F1), two (F2), three (F3), and four (F4), respectively. These fractions showed parasite membranes in the F1, rhoptry and conoids in the F2, mitochondria in the F3, and tachyzoite ghosts remain in F4. Indirect ELISAs for IgM, and IgG were performed. Additionally, sensitivity, specificity, and kappa values were defined considering the IFA as the gold standard. The highest and lowest specificities were observed for F1 (76 %) and F3 (16 %), respectively. F2 and F4 showed the highest sensitivity (93.3 %), kappa agreement (0.46), and Negative Preventive Value (NPV) (73 %) respectively. It was possible to standardize indirect ELISAs using whole soluble antigen and subcellular fractions of N. caninum, and F2 and F4 showed higher sensitivity (93.3 %), kappa (0.41), and NPV values (75 %) than F1, and F3, which could be used for epidemiology studies such as screening.

R-cVR, a two-step bedside algorithm for the differential diagnosis of acute dizziness and vertigo

BackgroundThe ability to quickly and accurately differentiate between peripheral and central dizziness or vertigo is vital. We developed the R-cVR algorithm for the early identification of central-type dizziness or vertigo. MethodsIn this single-center, retrospective cohort study, we assessed patients with isolated dizziness or vertigo between December 10, 2023, and February 28, 2024. Classification into central or peripheral types was based on magnetic resonance imaging (MRI)-diffusion-weighted imaging (DWI) results. We reevaluated the diagnostic value of the Romberg test for acute dizziness or vertigo by quantifying the duration of standing and created the R-cVR algorithm. The algorithm's accuracy was subsequently validated against the MRI-DWI results. ResultsAfter screening, 109 patients were recruited and divided into central (n = 25) and peripheral (n = 84) groups. The central group had a high incidence of cerebral infarction (88.0 %), whereas the peripheral group included patients with vestibular neuronitis, benign paroxysmal positional vertigo, and Meniere's disease (96.4 %). Significant disparities in the incidence of balance disorders were noted between the groups (92.0 % vs. 15.5 %, p < 0.001). Multivariate logistic regression revealed an odds ratio of 61.82 for balance disorders (p < 0.001). The R-cVR algorithm, which integrates the Romberg test and the V-shaped stance with closed-eyes protocol, was tested against MRI-DWI and yielded high diagnostic agreement (kappa = 0.80), with a sensitivity and specificity of 88.0 % and 94.0 %, respectively. There was no significant difference in the diagnostic efficacy of this algorithm for acute dizziness or vertigo with or without nystagmus. ConclusionThe R-cVR algorithm effectively identifies central-type dizziness or vertigo and is simple for general practitioners to use without specialized equipment, which may be valuable in various clinical settings.

Application value of individualized tube voltage, contrast injection, and adaptive statistical iterative reconstruction V algorithm based on body mass index in renal computed tomography angiography for radiation and iodinated contrast dose reduction.

To explore the application value of body mass index (BMI)-based kilovoltage peak (kVp) selection and contrast injection protocol combined with different adaptive statistical iterative reconstruction V (ASIR-V) strengths in renal computed tomography angiography (CTA) in reducing radiation and contrast medium (CM) doses. One-hundred renal CTA patients were prospectively enrolled and were divided into individualized kVp group (group A, n = 50) and conventional 100kVp group (group B, n = 50), both with automatic tube current modulation and CM of Iohexol at 350mgI/mL concentration. Group A: 70kVp, noise index (NI) of 18 and CM dose rate of 17mgI/kg/s for 10 s for BMI <25kg/m2 patients; 80kVp, NI = 17, and CM dose rate of 19mgI/kg/s for 10 s for 25 kg/m2≤BMI≤30kg/m2 patients. Group B: 100kVp, 50 mL of CM at the flow rate of 4.5 mL/s. The objective image quality, effective radiation dose, CM dose, injection rate, and image quality were compared between the 2 groups. There was no significant difference in patient characteristics between the 2 groups (P > .05). Compared to group B, group A significantly reduced effective radiation dose by 28.4%, CM dose by 27.2%, and injection rate by 22.7% (all P < .001). The 2 groups had similar SD values in erector spine (P > .05). Group A had significantly higher CT values, SNR, and CNR values of the renal arteries than group B (all P < .001). The 2 radiologists had excellent agreement (Kappa value > 0.8) in the subjective scores of renal CTA images and showed no statistically significant difference between the 2 groups (4.57 ± 0.42 vs 4.41 ± 0.49) (P > .05). BMI-based scan and reconstruction protocol in renal CTA significantly reduces radiation and contrast doses while maintaining diagnostic image quality. (i) BMI-based individualized tube voltage selection and contrast injection protocol in renal CTA reduces both radiation and contrast doses over conventional protocol. (ii) The combination of lower kVp and higher weight ASIR-V maybe used to improve image quality in terms of contrast enhancement and image noise under lower radiation and contrast dose conditions. (iii) Renal CTA of normal size (BMI ≤ 30kg/m2) patients acquired at low radiation dosage and low iodine contrast dose through the combination of low tube voltage and ASIR-V algorithm achieves excellent diagnostic image quality with a good inter-rater agreement.

The use of Loss Velocity and the Rate of Perceived Exertion to Assess Effort Intensity During Sets of Bench Press Exercise Performed until Exhaustion

The objective of the present study was to verify the agreement and correlation between effort intensity determined from the rate of perceived exertion (RPE) and loss velocity in sets performed to exhaustion in the bench press exercise at a self-selected velocity. Thirty-five men and women practitioners of resistance training (33.61±8.16 years; 172.75±11.04 cm of stature; 76.79±15.57 kg of body mass) were evaluated. Participants were familiarized and then performed two sets of bench press performed until exhaustion at a self-selected velocity at 70% and 85% of one-repetition maximum (1RM). Loss velocity was measured by a linear position transducer (Ergonauta® encoder) applied to velocity-based training. A 3-point RPE scale was used to evaluate the perceived exertion of the individuals. The analysis of agreement (Kappa test) and correlation (Spearman test) were applied (p&lt;0.05). The results of the study indicated the existence of a moderate degree of agreement (κ = 0.499; κ = 0.509 for 70% and 85% of 1RM, respectively), but a strong correlation (ρ = 0.720; ρ = 0.753 for 70% and 85% of 1RM, respectively) between the effort intensity determined by the Ergonauta and the RPE, at both intensities analyzed (70% and 85% of 1RM). Despite the lack of perfect agreement between methods, loss velocity and RPE seem to demonstrate strong consistency, allowing both to be used for controlling intensity in resistance training. The results of this study should be interpreted in light of individual characteristics, type of exercise, and training objectives.

Metal artifact reduction tool and mA levels impact on the diagnosis of fracture extension in endodontically treated teeth using cone-beam CT.

To evaluate the influence of different levels of metal artifact reduction (MAR) tool and milliamperage (mA) on the diagnosis of fracture extension in endodontically treated teeth using cone beam CT (CBCT). Ten maxillary premolars were endodontically treated and positioned in the empty sockets of a human maxilla covered with wax. CBCT acquisitions were performed using the Eagle Edge device (Dabi Atlante, Brazil) adjusted to 120 kVp, FOV of 4 × 6cm, exposure time of 24s and voxel size of 0.2mm in 8 different conditions with different MAR (1, 2 and 3) and mA (3.2 and 6.3) levels. Crown-root fractures were simulated in the universal testing machine, and CBCT images were acquired again. Five radiologists evaluated the presence and extension of fractures with a 5-point scale. Statistical analysis was performed by analysis of variance, Tukey and Kappa test (α = 0.05). Although different mA levels did not significantly (p > 0.05) affect the diagnosis values for fracture presence and extension, when evaluated the different levels of MAR, AUC and sensitivity showed significantly higher values (p < 0.05) for MAR 0 using 6.3mA and kappa agreement showed significantly higher values (p < 0.05) for MAR 0 and 2 using 6.3mA. Although mA levels do not have a diagnostic effect when isolating the MAR level; in 6.3mA, MAR 0 and 2 can positively influence the diagnosis of fracture extension in endodontically treated teeth using CBCT. The isolate evaluation of dental fracture presence can overlook diagnostics error of its extension.

Comparison of Copper (II) Sulphate to Hemocue Analyser in the Estimation of Haemoglobin among Voluntary and Replacement Blood Donors at Bugando Medical Centre

Background Pre-donation haemoglobin (Hb) screening is among the foremost test done on blood donors to determine whether an individual is fit to donate with the intention of preventing inadvertent donation from an anaemic donor. The National Blood Transfusion Service (NBTS) in Tanzania uses the Copper II Sulphate (CuSO4) gravimetric method to estimate haemoglobin (Hb) in blood donors. The accuracy of the copper II sulphate method for the rapid screening of prospective blood donors has been questioned because this rapid screening method may lead to false deferral of truly eligible prospective blood donors. However, this and other point-of-care method may provide false results. Methods This was a cross-sectional study conducted among 236 eligible blood donors attending BMC transfusion centre at Mwanza, Tanzania. The blood donors were asked for their consent to participate in this study from 1st May to 1st August 2024. Capillary blood samples were obtained for Hb estimation by CuSO4 and HemoCue methods, and 3mls of venous blood were also collected for Hb quantification by AHA (gold standard). Descriptive statistics were used to analyse the demographic details of the donor. Kappa statistics were used to determine the level of agreement between the two methods of Hb estimation. Results The median age of the study participants was 30 years (IQR: 25-36). The proportion of false eligible donors was 5.5%, and false deferral donors were 2.3% using the CuSO4 gravimetric method. The specificity, sensitivity, positive and negative predictive values, and Kappa agreement for CuSO4 were 53.8%, 94.7%, 93.8%, 58.3%, and 0.51, respectively. In contrast, the specificity, sensitivity, positive and negative predictive values, and Kappa agreement for HemoCue were 63.6%, 97.9%, 96%, 77.7%, and 0.67, respectively. Conclusion. The current study revealed that, the performance of the CuSO4 gravimetric method is relatively poor, with a high proportion of false eligible donors than the HemoCue method. These findings warrant further studies to evaluate the quality control measures for CuSO4 gravimetric method and explore alternative point-of-care methods for Hb estimation among blood donors in similar resource limited-settings.