Assess Interobserver Agreement Research Articles

Deep Learning Model for Grading and Localization of Lumbar Disc Herniation on Magnetic Resonance Imaging.

Methods for grading and localization of lumbar disc herniation (LDH) on MRI are complex, time-consuming, and subjective. Utilizing deep learning (DL) models as assistance would mitigate such complexities. To develop an interpretable DL model capable of grading and localizing LDH. Retrospective. 1496 patients (M/F: 783/713) were evaluated, and randomly divided into training (70%), validation (10%), and test (20%) sets. 1.5T MRI for axial T2-weighted sequences (spin echo). The training set was annotated by three spinal surgeons using the Michigan State University classification to train the DL model. The test set was annotated by a spinal surgery expert (as ground truth labels), and two spinal surgeons (comparison with the trained model). An external test set was employed to evaluate the generalizability of the DL model. Calculated intersection over union (IoU) for detection consistency, utilized Gwet's AC1 to assess interobserver agreement, and evaluated model performance based on sensitivity and specificity, with statistical significance set at P < 0.05. The DL model achieved high detection consistency in both the internal test dataset (grading: mean IoU 0.84, recall 99.6%; localization: IoU 0.82, recall 99.5%) and external test dataset (grading: 0.72, 98.0%; localization: 0.71, 97.6%). For internal testing, the DL model (grading: 0.81; localization: 0.76), Rater 1 (0.88; 0.82), and Rater 2 (0.86; 0.83) demonstrated results highly consistent with the ground truth labels. The overall sensitivity of the DL model was 87.0% for grading and 84.0% for localization, while the specificity was 95.5% and 94.4%. For external testing, the DL model showed an appreciable decrease in consistency (grading: 0.69; localization: 0.66), sensitivity (77.2%; 76.7%), and specificity (92.3%; 91.8%). The classification capabilities of the DL model closely resemble those of spinal surgeons. For future improvement, enriching the diversity of cases could enhance the model's generalization. Stage 2.

Assessment for Carotid Atherosclerotic Plaque Using Vessel Wall Magnetic Resonance Imaging: A Multireader ROC Study to Determine Optimal Sequence for Detecting Vessel Wall Calcification

Introduction: We aimed to compare conventional vessel wall MR imaging techniques and quantitative susceptibility mapping (QSM) to determine the optimal sequence for detecting carotid artery calcification. Methods: Twenty-two patients who underwent carotid vessel wall MR imaging and neck CT were enrolled. Four slices of 6-mm sections from the bilateral internal carotid bifurcation were subdivided into 4 segments according to clock position (0–3, 3–6, 6–9, and 9–12) and assessed for calcification. Two blinded radiologists independently reviewed a total of 704 segments and scored the likelihood of calcification using a 5-point scale on spin-echo imaging, FLASH, and QSM. The observer performance for detecting calcification was evaluated by a multireader, multiple-case receiver operating characteristic study. Weighted κ statistics were calculated to assess interobserver agreement. Results: QSM had a mean area under the receiver operating characteristic curve of 0.85, which was significantly higher than that of any other sequence (p < 0.01) and showed substantial interreader agreement (κ = 0.68). A segment with a score of 3–5 was defined as positive, and a segment with a score of 1–2 was defined as negative; the sensitivity and specificity of QSM were 0.75 and 0.87, respectively. Conclusion: QSM was the most reliable MR sequence for the detection of plaque calcification.

Interobserver Reliability of Cervical Vertebral Maturation Staging

Background: the accurate identification of a patient's maturation stage, particularly during the pubertal growth spurt, takes on heightened importance, particularly when addressing cases of dentoskeletal problem Active growth determination is crucial for orthodontic treatment. Objectives: The objective of this study was to determine interobserver reliability of Cervical Vertebrae Maturation (CVM) stagingMaterial and Methods: This cross-sectional correlational study, conducted in the Department of Orthodontics on 70 subjects. Ten orthodontic clinicians, including 4 orthodontists and 6 orthodontic residents, with no prior experience in CVM staging, underwent comprehensive training. The study involved assessing 70 lateral cephalograms with clear visibility of cervical vertebrae, evaluated by two independent examiners using the Baccetti et al. staging system. The collected data were analyzed using R programming, including descriptive statistics for age, Spearman's correlation, and Cohen's Kappa for assessing interobserver agreement, with stratification by gender. Results: The mean age of participants was 12.60±3.93 years, with 38 females (54.29%) and 32 males (45.71%). The study revealed varying levels of agreement between two observers for different CVM stages, ranging from perfect agreement in CS1 to strong agreement in CS3. CS4, CS5, and CS6 also showed varying agreement rates. Additionally, there was robust and statistically significant agreement (p&lt;0.001) between observers in cervical maturation staging, supported by a high Spearman's rho value (r=0.927). Furthermore, substantial agreement was observed with a Kappa value of 0.748, indicating a strong consensus in cervical staging assessments.Conclusion: Cervical vertebral maturation staging is reliable in term of inter-observers agreement. Keywords: Cervical vertebral maturation, Interobserver agreement, Growth assessment

Interobserver variability in thyroid ultrasound.

Ultrasound evaluation of thyroid nodules is the preferred technique, but it is dependent on operator interpretation, leading to inter-observer variability. The current study aimed to determine the inter-physician consensus on nodular characteristics, risk categorization in the classification systems, and the need for fine needle aspiration puncture. Four endocrinologists from the same center blindly evaluated 100 ultrasound images of thyroid nodules from 100 different patients. The following ultrasound features were evaluated: composition, echogenicity, margins, calcifications, and microcalcifications. Nodules were also classified according to ATA, EU-TIRADS, K-TIRADS, and ACR-TIRADS classifications. Krippendorff's alpha test was used to assess interobserver agreement. The interobserver agreement for ultrasound features was: Krippendorff's coefficient 0.80 (0.71-0.89) for composition, 0.59 (0.47-0.72) for echogenicity, 0.73 (0.57-0.88) for margins, 0.55 (0.40-0.69) for calcifications, and 0.50 (0.34-0.67) for microcalcifications. The concordance for the classification systems was 0.7 (0.61-0.80) for ATA, 0.63 (0.54-0.73) for EU-TIRADS, 0.64 (0.55-0.73) for K-TIRADS, and 0.68 (0.60-0.77) for K-TIRADS. The concordance in the indication of fine needle aspiration puncture (FNA) was 0.86 (0.71-1), 0.80 (0.71-0.88), 0.77 0.67-0.87), and 0.73 (0.64-0.83) for systems previously described respectively. Interobserver agreement was acceptable for the identification of nodules requiring cytologic study using various classification systems. However, limited concordance was observed in risk stratification and many ultrasonographic characteristics of the nodules.

Prediction of bowel necrosis by reduced bowel wall enhancement in closed-loop small bowel obstruction: Quantitative methods

PurposeTo assess diagnostic performance and reproducibility of reduced bowel wall enhancement evaluated by quantitative methods using CT to identify bowel necrosis among closed-loop small bowel obstruction (CL-SBO) patients. MethodsThis retrospective single-center study included patients who diagnosed with CL-SBO caused by adhesion or internal hernia during January 2016 and May 2022. Patients were divided into necrotic group (n = 41) and non-necrotic group (n = 67) according to surgical exploration and postoperative pathology. Two doctors independently measured the attenuation of bowel wall and consensus was reached through panel discussion with a third gastrointestinal radiologist. Reduced bowel wall enhancement was assessed by four quantitative methods. Univariate analyses were used to evaluate the association between each method and bowel necrosis, and kappa/intraclass correlation coefficient values were used to assess interobserver agreement. Diagnostic performance parameters were calculated for each method. ResultsReduced bowel wall enhancement in arterial phase (OR 8.98, P < 0.0001), reduced bowel wall enhancement in portal phase (OR 16.84, P < 0.001), adjusted reduced bowel wall enhancement in arterial phase (OR 29.48, P < 0.001), adjusted reduced bowel wall enhancement in portal phase (OR 145.69, P < 0.001) were significantly associated with bowel necrosis. Adjusted reduced bowel wall enhancement in portal phase had the best diagnostic performance (AUC: 0.92; Youden index: 0.84; specificity: 94.03 %) and interobserver agreement (kappa value of 0.59–0.73) to predict bowel necrosis. ConclusionWhen assessing reduced bowel enhancement to predict bowel necrosis among CL-SBO patients, using unenhanced CT images and proximal dilated loop as standard references in portal phase is the most accurate quantitative method among those tested.

Increased Attenuation of Intestinal Contents at CT Indicates Bowel Necrosis in Closed-Loop Small Bowel Obstruction.

Background Preoperative recognition of irreversible bowel necrosis is important, as it provides valuable guidance for surgical strategy selection but also may inform perioperative risk assessment and communication. Few studies have focused on the association between CT signs and bowel necrosis. Purpose To assess the diagnostic accuracy of CT signs to predict bowel necrosis in patients with closed-loop small bowel obstruction (CL-SBO). Materials and Methods This retrospective single-center study included patients who were surgically confirmed to have CL-SBO caused by adhesion or internal hernia between January 2016 and May 2022. Necrosis was determined based on surgical exploration and postoperative pathologic examination. Two radiologists independently reviewed CT signs by both subjective visual assessment and objective measurement. Disagreements were resolved in consensus with a third gastrointestinal radiologist. Univariable and multivariable analyses were used to assess the association between CT signs and bowel necrosis, and Cohen κ was used to assess interobserver agreement. Sensitivity and specificity were calculated for each CT sign. Results This study included 145 patients: 61 (42.1%) in the necrotic group (median age, 62 years [IQR, 51-71.5 years]; 37 [60.7%] women) and 84 (57.9%) in the nonnecrotic group (median age, 61.5 years [IQR, 51-68.8 years]; 51 [60.7%] women). Univariable analysis and multivariable analysis showed that increased attenuation of intestinal contents and increased attenuation of intestinal wall were independent predictors for bowel necrosis (odds ratio = 45.3 and 15.1; P = .001 and P < .001, respectively). Increased attenuation of intestinal contents and increased attenuation of intestinal wall had similar sensitivity (64% and 67%, respectively) and specificity (99% and 92%, respectively) for predicting bowel necrosis. However, interobserver agreement was better for assessing the contents than the wall (κ = 0.84 and 0.59, respectively). Conclusion Increased attenuation of intestinal contents was a highly specific CT sign with good reproducibility to predict bowel necrosis in CL-SBO. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Taourel and Zins in this issue.

Reproducibility and Repeatability of Intravoxel Incoherent Motion MRI Acquisition Methods in Liver.

Intravoxel incoherent motion (IVIM) diffusion weighted MRI (DWI) has potential for evaluating hepatic fibrosis but image acquisition technique influence on diffusion parameter estimation bears investigation. To minimize variability and maximize repeatably in abdominal DWI in terms of IVIM parameter estimates. Prospective test-retest and image quality comparison. Healthy volunteers (3F/7M, 29.9 ± 12.9 years) and Family Study subjects (18F/12M, 51.7 ± 16.7 years), without and with liver steatosis. Abdominal single-shot echo-planar imaging (EPI) and simultaneous multi-slice (SMS) DWI sequences with respiratory triggering (RT), breath-holding (BH), and navigator echo (NE) at 3 Tesla. SMS-BH, EPI-NE, and SMS-RT data from twice-scanned healthy volunteers were analyzed using 6 × b-values (0-800 s⋅mm-2 ) and lower (LO) and higher (HI) b-value ranges. Family Study subjects were scanned using SMS and standard EPI sequences. The biexponential IVIM model was used to estimate fast-diffusion coefficient (Df ), fraction of fast diffusion (f), and slow-diffusion coefficient (Ds ). Scan time, estimated signal-to-noise ratio (eSNR), eSNR per acquisition, and distortion ratio were compared. Coefficients of variation (CoV) and Bland Altman analyses were performed for test-retest repeatability. Interclass correlation coefficient (ICC) assessed interobserver agreement with P < 0.05 deemed significant. Within-subject CoVs among volunteers (N = 10) for f and Ds were lowest in EPI-NE-LO (11.6%) and SMS-RT-HI (11.1%). Inter-observer ICCs for f and Ds were highest for EPI-NE-LO (0.63) and SMS-RT-LO (0.76). Df could not be estimated for most subjects. Estimated eSNR (EPI = 21.9, SMS = 4.7) and eSNR time (EPI = 6.7, SMS = 16.6) were greater for SMS, with less distortion in the liver region (DR-PE: EPI = 23.6, SMS = 13.1). Simultaneous multislice acquisitions had significantly less variability and higher ICCs of Ds , higher eSNR, less distortion, and reduced scan time compared to EPI. 2 TECHNICAL EFFICACY: Stage 1.

ChatGPT's Accuracy on Magnetic Resonance Imaging Basics: Characteristics and Limitations Depending on the Question Type.

Our study aimed to assess the accuracy and limitations of ChatGPT in the domain of MRI, focused on evaluating ChatGPT's performance in answering simple knowledge questions and specialized multiple-choice questions related to MRI. A two-step approach was used to evaluate ChatGPT. In the first step, 50 simple MRI-related questions were asked, and ChatGPT's answers were categorized as correct, partially correct, or incorrect by independent researchers. In the second step, 75 multiple-choice questions covering various MRI topics were posed, and the answers were similarly categorized. The study utilized Cohen's kappa coefficient for assessing interobserver agreement. ChatGPT demonstrated high accuracy in answering straightforward MRI questions, with over 85% classified as correct. However, its performance varied significantly across multiple-choice questions, with accuracy rates ranging from 40% to 66.7%, depending on the topic. This indicated a notable gap in its ability to handle more complex, specialized questions requiring deeper understanding and context. In conclusion, this study critically evaluates the accuracy of ChatGPT in addressing questions related to Magnetic Resonance Imaging (MRI), highlighting its potential and limitations in the healthcare sector, particularly in radiology. Our findings demonstrate that ChatGPT, while proficient in responding to straightforward MRI-related questions, exhibits variability in its ability to accurately answer complex multiple-choice questions that require more profound, specialized knowledge of MRI. This discrepancy underscores the nuanced role AI can play in medical education and healthcare decision-making, necessitating a balanced approach to its application.

Evaluation of Induced Sputum against Gastric Juice Aspirate in the Diagnosis of Tuberculosis in Children: A Cross-sectional Study

Introduction: Diagnosing Tuberculosis (TB) in children is difficult as they do not expectorate sputum on their own, and the sample is usually paucibacillary. Hence, alternative sampling methods like Gastric juice Aspiration (GA), which is the widely accepted method, and Induced Sputum (IS) collection, a more novel approach, are used. The IS method has several advantages, such as being less invasive, not requiring inpatient admission, causing less discomfort, and not necessitating overnight fasting, compared to the GA method. Aim: To evaluate IS against GA for diagnosing TB using XpertMTB/ RIF assay, as well as mycobacterial culture, in children aged between 2 and 15 years. Materials and Methods: This cross-sectional study was conducted in the Department of Paediatrics at Christian Medical College and Hospital, Vellore, Tamil Nadu, India from June 2019 to March 2020, involving 138 children aged between 2 and 15 years who were being evaluated for TB. GA samples were collected after an overnight fast, and on the same day, atleast two hours later, IS samples were collected by trained staff. Both samples underwent mycobacterial smear and culture using the Mycobacteria Growth Indicator Tube (MGIT) method and Xpert MTB/RIF assay. Confirmation of pulmonary TB was based on atleast one of these tests being positive. The ‘Wong-Baker’ Visual Analogue Scale (VAS) was individually administered to each patient to compare the discomfort associated with GA and IS procedures. The differences in yield between IS and GA were tested for significance using the Two-sample test of proportions with a significance level set at 5%. McNemar's χ2 test was employed to compare matched observations. The MannWhitney test was used for comparing continuous variables, and the Chi-Square test for categorical variables. Cohen’s Kappa (κ) was used to assess interobserver agreement between the sampling methods using the different tests. Results: Out of the 138 cases recruited with suspected pulmonary TB, the diagnosis was microbiologically confirmed in 13 cases (9.4%). The overall diagnostic yield was 12/138 (8.7%) for GA and 10/138 (7.2%) for IS. In children under 10 years, GA outperformed IS with all three cases being positive by GA and none by IS. For those aged 10 years and above, 10 children (100%) tested positive with IS, while nine children (90%) were positive with GA. According to the Wong-Baker VAS measuring discomfort during the procedure, IS was favoured over GA (p-value&lt;0.0001). Conclusion: IS performs similarly or better than GA in children over 10 years, while GA performs better than IS in children under 10 years of age. IS is reported to cause less discomfort than GA on the Wong-Baker VAS.

Optimal Size Threshold for MRI-Detected Retropharyngeal Lymph Nodes to Predict Outcomes in Nasopharyngeal Carcinoma: A Two-Center Study.

BACKGROUND. Retropharyngeal lymph node (RLN) metastases have profound prognostic implications in patients with nasopharyngeal carcinoma (NPC). However, the AJCC staging system does not specify a size threshold for determining RLN involvement, resulting in inconsistent thresholds in practice. OBJECTIVE. The purpose of this article was to determine the optimal size threshold for determining the presence of metastatic RLNs on MRI in patients with NPC, in terms of outcome predictions. METHODS. This retrospective study included 1752 patients (median age, 46 years; 1297 men, 455 women) with NPC treated by intensity-modulated radiotherapy (RT) from January 2010 to March 2014 from two hospitals; 438 patients underwent MRI 3-4 months after treatment. Two radiologists measured the minimal axial diameter (MAD) of the largest RLN for each patient using a consensus process. A third radiologist measured MAD in 260 randomly selected patients to assess interobserver agreement. Initial ROC and restricted cubic spline (RCS) analyses were used to derive an optimal MAD threshold for predicting progression-free survival (PFS). The threshold's predictive utility was assessed in multivariable Cox regression analyses, controlling for standard clinical predictors. The threshold's utility for predicting PFS and overall survival (OS) was compared with a 5-mm threshold using Kaplan-Meier curves and log-rank tests. RESULTS. The intraclass correlation coefficient for MAD was 0.943. ROC and RCS analyses yielded an optimal threshold of 6 mm. In multivariable analyses, MAD of 6 mm and greater independently predicted PFS in all patients (HR = 1.35, p = .02), patients with N0 or N1 disease (HR = 1.80, p = .008), and patients who underwent posttreatment MRI (HR = 1.68, p = .04). In patients with N1 disease without cervical lymph node involvement, 5-year PFS was worse for MAD greater than or equal to 6 mm than for MAD that was greater than or equal to 5 mm but less than 6 mm (77.2% vs 89.7%, p = .03). OS was significantly different in patients with stage I and stage II disease defined using a 6-mm threshold (p = .04), but not using a 5-mm threshold (p = .09). The 5-year PFS rate was associated with a post-RT MAD of 6 mm and greater (HR = 1.68, p = .04) but not a post-RT MAD greater than or equal to 5 mm (HR = 1.09, p = .71). CONCLUSION. The findings support a threshold MAD of 6 mm for determining RLN involvement in patients with NPC. CLINICAL IMPACT. Future AJCC staging updates should consider incorporation of the 6-mm threshold for N-category and tumor-stage determinations.

Interobserver agreement for the Vesical Imaging-Reporting and Data System (VI-RADS) in differentiating non-muscle-invasive and muscle-invasive urinary bladder tumors

BackgroundBladder cancer is the most common tumor of the genitourinary tract. Transitional cell carcinoma is divided into two categories: non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC). In spite of the high recurrence rate, NMIBC has good prognosis, while MIBC has poor prognosis due to local organ invasion and metastases. Mp-MRI shows better tumor detection and staging. The aim of this study is to validate VI-RADS in detecting MIBC and assessing interobserver agreement and impact of reader's experience.ResultsAt cutoff value of VI-RADS score ≥ 3, the VI-RADS showed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 96.8%,83.3%, 93.8%, 90.9%, and 93%, respectively, for reader 1, 93.5%, 91.7%, 84.6%, and 93% for reader 2, and 96.8%,83.3%, 93.8%, 90.9%, and 93% for reader 3. The interobserver agreement between individual readers was excellent among the three readers.ConclusionsVesical imaging-reporting and data system (VI-RADS) is a good method showing satisfactory sensitivity, specificity, and diagnostic value for detecting detrusor muscle invasion.

Incidental Indeterminate Renal Lesions: Distinguishing Non-Enhancing from Potential Enhancing Renal Lesions Using Iodine Quantification on Portal Venous Dual-Layer Spectral CT.

The purpose of our study is to determine a threshold for iodine quantification to distinguish definitely non-enhancing benign renal lesions from potential enhancing masses on portal venous dual-layer spectral computed tomography (CT) to reduce the need for additional multiphase CT. In this single-center retrospective study, patients (≥18 years) scanned between April 2021 and January 2023 following the local renal CT protocol were included. Exclusion criteria were patients without renal lesions, lesions smaller than 10 mm, only fat-containing lesions, abscesses or infarction, follow-up after radiofrequent ablation, wrong scan protocol, or artefacts. Scans were performed on a dual layer detector-based spectral CT (CT 7500, Philips Healthcare, Best, The Netherlands). Iodine concentration (mgI/mL) in renal lesions was determined using spectral data. Analyses were performed for all lesions and for lesions of >30 HU on portal venous CT. Enhancement on multiphase CT (≥20 ΔHU from true unenhanced (TUE) to portal venous phase (PVP) CT) was used as reference standard. To determine thresholds for iodine concentration receiver operating characteristic (ROC) curves, area under the curve (AUC) and 95% confidence intervals were calculated. To obtain thresholds for definite (non-)enhancement, 100% sensitivity with maximum specificity and 100% specificity with maximum sensitivity were noted. Data were measured using one reader. To assess interobserver agreement, a second reader performed measurements on the PVP CT scans. A total of 103 patients (62 years ± 14, 68 men) were included. We measured 328 renal lesions, 56 enhancing lesions (17%) in 38 patients and 272 non-enhancing lesions (83%) in 86 patients. The threshold for non-enhancing lesions was 0.76 mgI/mL or lower (100% sensitivity, 76% specificity). The threshold for a definite enhancing mass was 1.69 mgI/mL or higher (100% specificity, 78% sensitivity). A total of 77% of indeterminate lesions (>30 HU on PVP CT) in our study could be definitely characterized. Renal lesions can be definitively classified as non-enhancing or enhancing on PVP spectral CT using thresholds of 0.76 mgI/mL or 1.69 mgI/mL, respectively, eliminating the need for multiphase imaging.

A study to assess interobserver agreement for measuring the intraocular pressure using Goldmann applanation tonometry by two ophthalmologists

A study to assess interobserver agreement for measuring the intraocular pressure using Goldmann applanation tonometry by two ophthalmologists

Agreement between pharmacists and physicians on the assessment of appropriateness of antimicrobial prescribing

IntroductionAudits for monitoring the quality of antimicrobial prescribing are a main tool in antimicrobial stewardship programs; however, interobserver reliability has not been conclusively assessed. Our objective was to measure the level of agreement between pharmacists and physicians on the appropriateness of antimicrobials prescribing in hospitals. MethodsA national multicenter, cross-sectional study was conducted of patients who were receiving antimicrobials one day of April 2021. Hospital participation was voluntary, and the study population was randomly selected. Pharmacists and physicians performed a simultaneous, independent assessment of the quality of antimicrobial prescriptions. The observers used an assessment method by which all indicators of the quality of antimicrobial use were considered. Finally, an algorithm was used to rate overall antimicrobial prescribing as appropriate, suboptimal, inappropriate, or not assessable. Gwet's AC1 coefficient was used to assess interobserver agreement. ResultsIn total, 101 hospitals participated, and 411 hospital antimicrobial prescriptions were reviewed. The strength of agreement was moderate regarding the overall quality of prescribing (AC1=0.51; 95%CI=[0.44–0.58]). A very good level of agreement (AC1>0.80) was observed between pharmacists and physicians in all indicators of the quality, except for duration of treatment, rated as good (AC1=0.79; 95%CI=[0.75–0.83]), and registration on the medical record, rated as fair (AC1=0.34; 95%CI=[0.26–0.43]). The agreement was greater in critical care, onco-hematology, and pediatric units than in medical and surgery units. ConclusionsIn this point prevalence study, a moderate level of agreement was observed between pharmacists and physicians in the evaluation of the appropriateness of antimicrobials prescribing in hospitals.

Diagnostic Accuracy of Hyperpigmented Microcircles in Dermatoscopy of Non-Facial Non-Acral Melanomas: A Pilot Retrospective Study using a Public Image Database

Background: Grey perifollicular circles are a dermatoscopic clue to melanoma, especially in facial skin. So far, no other adnexal clues than follicular have been investigated in this diagnosis. Objectives: The study aimed to analyse the prevalence of hyperpigmented periadnexal microcircles (HMs) in melanoma and its common simulators at non-facial non-acral sites, analyse the relation between the presence of HM, regression and hypopigmentation, and evaluate the diagnostic accuracy of this structure in melanoma. Methods: International Skin Imaging Collaboration (69,445 images) was searched in April 2020 for the pathology-confirmed dermatoscopic images with metadata including sex, age bin, and declared non-acral non-facial anatomic site. The final study sample (5,408 images, 1,326 of which were melanomas) was evaluated by expert dermatoscopist blinded to the diagnosis and labelled for the presence of ≥3 HM distributed centrally (cHM) or peripherally (pHM), hypopigmentation, and classic dermatoscopic regression structures. A subset of 40 images was labelled by 7 raters (2 residents, 5 experts) to assess interobserver agreement. We compared the presence of pHM with the presence of regression as well as performed a set of independent χ² tests to evaluate the discriminatory power and its fragility. Performance of the models was assessed using measures of discrimination and calibration. Results: HM were significantly more prevalent in melanomas than in non-melanomas and nevi. Fair/good interobserver agreement for HM was reached for all the raters, and moderate/good for experts only (single rater/average, respectively). Regardless of regression/hypopigmentation status, pHM were significantly more common in melanoma than in non-melanomas or nevi and were observed significantly more often in melanomas on sun-damaged skin (upper extremity, posterior torso). No significant differences between the groups were found for cHM. pHM proved a high odds ratio in the tests as to the classical indicators such as classic dermatoscopic regression structures. Conclusion: pHM could be considered a novel dermatoscopic clue to melanoma.

Single vs. Multiphase Computed Tomography angiography in acute internal carotid artery occlusion: An accuracy and interobserver agreement study

ObjectiveAccurate differentiation between the intracranial and extracranial location of the acute internal carotid artery (ICA) occlusion is essential for guiding treatment decisions and mechanical thrombectomy planning. Multiphase Computed Tomography angiography (mCTA) appears to be superior to Single-phase Computed Tomography angiography (sCTA) in the evaluation of acute ICA occlusions. The main objective of our research is to study the accuracy of mCTA compared to sCTA in distinguishing isolated acute intracranial ICA occlusion from extracranial or tandem occlusion. MethodsTwo observers independently analyzed sCTA and mCTA of patients with acute ICA occlusion at two different time points. The location of the occlusion was categorized as intracranial or extracranial for both imaging techniques and then compared with digital subtraction angiography (gold standard). Sensitivity and specificity rates for isolated intracranial ICA occlusion on sCTA and mCTA were calculated. Kappa statistics were used to assess interobserver agreement. ResultsThe sensitivity of sCTA and mCTA was 48.28% (28.36%–68.19%) and 79.31% (62.84%–95.78%) respectively for the diagnosis of isolated intracranial ICA occlusion, with an almost perfect interobserver agreement between both observers (p < 0.001). ConclusionsOur research suggests that mCTA is more accurate than sCTA in distinguishing isolated intracranial occlusions from extracranial or tandem occlusions.

Agreement between pharmacists and physicians on the assessment of appropriateness of antimicrobial prescribing

IntroductionAudits for monitoring the quality of antimicrobial prescribing are a main tool in antimicrobial stewardship programs; however, interobserver reliability has not been conclusively assessed. Our objective was to measure the level of agreement between pharmacists and physicians on the appropriateness of antimicrobials prescribing in hospitals. MethodsA national multicenter, cross-sectional study was conducted of patients who were receiving antimicrobials one day of April 2021. Hospital participation was voluntary, and the study population was randomly selected. Pharmacists and physicians performed a simultaneous, independent assessment of the quality of antimicrobial prescriptions. The observers used an assessment method by which all indicators of the quality of antimicrobial use were considered. Finally, an algorithm was used to rate overall antimicrobial prescribing as appropriate, suboptimal, inappropriate, or not assessable. Gwet's AC1 coefficient was used to assess interobserver agreement. ResultsIn total, 101 hospitals participated, and 411 hospital antimicrobial prescriptions were reviewed. The strength of agreement was moderate regarding the overall quality of prescribing (AC1=0.51; 95%CI=[0.44–0.58]). A very good level of agreement (AC1>0.80) was observed between pharmacists and physicians in all indicators of the quality, except for duration of treatment, rated as good (AC1=0.79; 95%CI=[0.75–0.83]), and registration on the medical record, rated as fair (AC1=0.34; 95%CI=[0.26–0.43]). The agreement was greater in critical care, onco-hematology, and pediatric units than in medical and surgery units. ConclusionsIn this point prevalence study, a moderate level of agreement was observed between pharmacists and physicians in the evaluation of the appropriateness of antimicrobials prescribing in hospitals.

Should we use a semi-quantitative assessment of apical rocking to predict outcome in CRT patients?

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Apical rocking (AR) is a systolic septal-to-lateral motion of the apex observed on echocardiography in the apical 4-chamber view in some patients with a ventricular conduction delay. It is a strong predictor for outcome after cardiac resynchronization therapy (CRT) and has been suggested as selection criterion for CRT. Critics argue that simple visual assessment of AR may be too subjective for clinical use. Speckle-tracking based myocardial motion analysis may allow to objectify AR and may reduce a potential observer dependence. Purpose To compare the visual assessment of AR (VAR) to the semi-quantitative assessment of AR (QAR) in patients for the prediction of (i) volume response and (ii) all-cause death after CRT. To assess interobserver agreement for VAR and QAR. Methods We retrospectively analyzed data from 166 patients with a first CRT implantation. All patients had an echo before CRT implantation and approximately 1 year after implantation. VAR and QAR analysis were performed by three experienced observers on echocardiographic apical 4-chamber views before CRT implantation. QAR was obtained by performing speckle-tracking in the apical segments of the lateral and septal wall. A negative lateral displacement with a positive septal displacement during systole was considered as AR (Figure). Areas under the ROC-curves (AUC) for prediction of volume response were determined and compared using the DeLong method. Volume response was defined as a ≥15% decrease in left ventricular end-systolic volume (LVESV) within 1 year. Patients were followed for a mean duration of 5.2 years. Hazard ratios (HR) for all-time all-cause death after CRT were calculated using an univariate Cox proportional-hazards regression model. Interobserver agreement was analysed using the intraclass correlation coefficient (ICC) based on an average measurement, absolute agreement, two-way mixed effects model. Results 77% (n = 122) of patients were volume responders. Seven patients died before follow-up echocardiography. 31% (n = 52) of patients died during follow-up. AUC for volume response were similar for VAR and QAR (0.73 vs 0.72, p = 0.782). HR for all-time all-cause death were similar for VAR (0.39, 0.25–0.61; p&amp;lt;0.001) and QAR (0.37, 0.23–0.59; p&amp;lt;0.001). ICC was good for VAR (0.78; 0.55–0.90) and QAR (0.84; 0.67–0.93). Conclusion Semi-quantification of AR (QAR) using speckle-tracking technology achieves comparable results as the simple visual assessment of AR (VAR) when performed by an experienced reader for prediction of volume response and prediction of all-cause death in patients eligible for CRT. Interobserver agreement for VAR and QAR was similarly good. QAR could be used as confirmation of the visual assessment and may support clinicians less familiar with the visual assessment.

PET/CT reading for relapse in non-small cell lung cancer after chemoradiotherapy in the PET-Plan trial cohort

BackgroundCurrent studies indicate that fluorine-18-fluorodeoxyglucose positron emission tomography/ computed tomography ([18F]FDG PET/CT) is the most accurate imaging modality for the detection of relapsed locally advanced non-small cell lung cancer (NSCLC) after curatively intended chemoradiotherapy. To this day, there is no objective and reproducible definition for the diagnosis of disease recurrence in PET/CT, the reading of which is relevantly influenced by post radiation inflammatory processes. The aim of this study was to evaluate and compare visual and threshold-based semi-automated evaluation criteria for the assessment of suspected tumor recurrence in a well-defined study population investigated during the randomized clinical PET-Plan trial.MethodsThis retrospective analysis comprises 114 PET/CT data sets of 82 patients from the PET-Plan multi-center study cohort who underwent [18F]FDG PET/CT imaging at different timepoints for relapse, as suspected by CT. Scans were first analyzed visually by four blinded readers using a binary scoring system for each possible localization and the associated reader certainty of the evaluation. Visual evaluations were conducted repeatedly without and with additional knowledge of the initial staging PET and radiotherapy delineation volumes. In a second step, uptake was measured quantitatively using maximum standardized uptake value (SUVmax), peak standardized uptake value corrected for lean body mass (SULpeak), and a liver threshold-based quantitative assessment model. Resulting sensitivity and specificity for relapse detection were compared to the findings in the visual assessment. The gold standard of recurrence was independently defined by prospective study routine including external reviewers using CT, PET, biopsies and clinical course of the disease.ResultsOverall interobserver agreement (IOA) of the visual assessment was moderate with a high difference between secure (ĸ = 0.66) and insecure (ĸ = 0.24) evaluations. Additional knowledge of the initial staging PET and radiotherapy delineation volumes improved the sensitivity (0.85 vs 0.92) but did not show significant impact on the specificity (0.86 vs 0.89). PET parameters SUVmax and SULpeak showed lower accuracy compared to the visual assessment, whereas threshold-based reading showed similar sensitivity (0.86) and higher specificity (0.97).ConclusionVisual assessment especially if associated with high reader certainty shows very high interobserver agreement and high accuracy that can be further increased by baseline PET/CT information. The implementation of a patient individual liver threshold value definition, similar to the threshold definition in PERCIST, offers a more standardized method matching the accuracy of experienced readers albeit not providing further improvement of accuracy.

Feasibility of Quantitative MRI Using 3D-QALAS for Discriminating Immunohistochemical Status in Invasive Ductal Carcinoma of the Breast.

Two-dimensional synthetic MRI of the breast has limited spatial coverage. Three-dimensional (3D) synthetic MRI could provide volumetric quantitative parameters that may reflect the immunohistochemical (IHC) status in invasive ductal carcinoma (IDC) of the breast. To evaluate the feasibility of 3D synthetic MRI using an interleaved Look-Locker acquisition sequence with a T2 preparation pulse (QALAS) for discriminating the IHC status, including hormone receptor (HR), human epidermal growth factor receptor 2 (HER 2), and Ki-67 expression in IDC. Prospective observational study. A total of 33 females with IDC of the breast (mean, 52.3 years). A 3-T, 3D-QALAS gradient-echo and fat-suppressed T1-weighted 3D fast spoiled gradient-echo sequences. Two radiologists semiautomatically delineated 3D regions of interest (ROIs) of the whole tumors on the dynamic MRI that was registered to the synthetic T1-weighted images acquired from 3D-QALAS. The mean T1 and T2 were measured for each IDC. Intraclass correlation coefficient for assessing interobserver agreement. Mann-Whitney U test to determine the relationship between the mean T1 or T2 and the IHC status. Multivariate logistic regression analysis followed by receiver operating characteristics (ROC) analysis for discriminating IHC status. A P value <0.05 was considered statistically significant. The interobserver agreement was good to excellent. There was a significant difference in the mean T1 between HR-positive and HR-negative lesions, while the mean T2 value differed between HR-positive and HR-negative lesions, between the triple-negative and HR-positive or HER2-positive lesions, and between the Ki-67 level > 14% and ≤ 14%. Multivariate analysis showed that the mean T2 was higher in HR-negative IDC than in HR-positive IDC. ROC analysis revealed that the mean T2 was predictive for discriminating HR status, triple-negative status, and Ki-67 level. 3D synthetic MRI using QALAS may be useful for discriminating IHC status in IDC of the breast. 1. Stage 2.