Intraobserver Comparisons Research Articles

Utility of digital cell imaging as an aid to enhance pathologist peripheral blood smear review for routine and on call practice: A verification study

Abstract Introduction/Objective Microscopic examination of peripheral blood smear (PBS) provides important information to support the diagnosis of hematological diseases. However, manual microscopic examination of PBS is labor-intensive and cannot be done remotely. CellaVision is digital cell imaging technology that provides pre-classification and digital imaging of the red blood cells (RBCs), white blood cells (WBCs), and platelets, myeloid, lymphoid and erythroid precursors. Several studies have evaluated the performance of this technology in the hematology laboratory as tool to assist laboratory technologists; our study evaluates its use for pathologist review of peripheral blood smears both during routine and on call practice. Methods/Case Report Our study included 30 PBS and two hematopathologists with greater than 10 years’ experience in performing PBS review. We compared pathologist’s own impression of microscopic PBS review to their own impression using CellaVision software (intraobserver comparison). Additionally, pathologist to pathologist impression was compared for both methods (interobserver comparison). All 30 cases revealed abnormal findings including, but not limited to: pancytopenia, leukocytosis, leukopenia, anemia, thrombocytopenia, and thrombocytosis. Of the 30 cases, 5 “on-call” were cases when the pathologist had to come on–site for pathologist PBS review. Results (if a Case Study enter NA) The pathologists own PBS interpretation (intraobserver) by microscopy and CellaVision had a concordance of 96.7%. The pathologist to pathologist interpretation of both methods had a concordance of 96.7%.The one discrepant case was a smear with platelet clumping and normal platelet count. On chart review of this case, this discrepancy would have minimal impact on patient care. Conclusion Pathologist use of CellaVision in their routine practice may result in speedier PBS review, particularly in cases with leukopenia, and better communication with laboratory technologists. CellaVision is less reliable in identifying platelet clumps and should not be used in isolation in evaluating thrombocytopenia. Used with other relevant data, CellaVision has the potential to preempt in person microscopic review of PBS when on-call in certain situations.

Abstract 6083: Inter-observer agreement in ultrasound-detected steatotic liver in the Chile Biliary Longitudinal Study (BiLS)

Abstract Background: Metabolic-associated steatotic liver disease (MASLD) is a prevalent chronic liver condition with an increased risk of cancer-related mortality. In Latin America, MASLD prevalence is estimated at 40%, with Chile reporting rates of 47.5% in 2019. Early detection is crucial for MASLD control and management. Liver biopsy, the gold standard for diagnosis, is invasive and costly. Ultrasound (US) is a preferred alternative, yet its precision varies depending on the observer interpretation. Methods: We conducted a cross-sectional analysis of a subset of baseline US images from the Chile Biliary Longitudinal Study (Chile BiLS), a cohort of women aged 50-74 with gallstones in Chile. Of the 4,032 participants recruited from Cautín Province in the Araucanía region, a random sample of 10% of the images were selected for review by a radiologist from Baylor College of Medicine (Observer 1) and compared to the original readings generated at the baseline exam by a team of Chile BiLS ultrasound technicians. To assess reproducibility, 33 blinded duplicate images from the 10% sample were reanalyzed by Observer 1 and an additional Chile BiLS technician who was not part of the original baseline team (Observer 2). Inter- and intra-observer agreement was assessed using weighted kappa values. Images were categorized as none, mild, moderate/severe. Results: Of the 409 images reviewed, agreement between Observer 1 and original readings across all categories of steatosis was poor (kappa: 0.09; CI 95% 0.06;0.11, p <0.001). The 33 duplicates compared to the original readings showed slight agreement for Observer 1 (kappa: 0.11 CI 95% 0.02;0.20, p <0.05) and fair for Observer 2 (kappa: 0.28 (CI 95% 0.07 - 0.49, p <0.001). The intra-observer agreement for Observer 1 was moderate, with a kappa of 0.41 (CI 95% 0.09 - 0.74, p <0.05), and for Observer 2, it was substantial with a weighted kappa of 0.69 (CI 95% 0.5 - 0.9, p <0.001). Conclusion: The study highlights the variability in US interpretation of hepatic steatosis, emphasizing the importance of standardized training and methodology. US's sensitivity and specificity is operator dependence, which impacts the diagnostic interpretation. Our findings underscore the significance of inter and intra-observer comparisons for optimal diagnosis, especially when US is the primary diagnostic tool in MASLD assessment. Finally, our results emphasize the importance of group training. Observer 2, who underwent the same training as the original Chile BiLS ultrasound technicians and was consistently exposed to this technique as a diagnostic method, exhibited more consistent results. This reinforces the importance of collective training initiatives to enhance the reliability and accuracy of US in MASLD diagnosis. Citation Format: Maria Spencer Sandino, Vanessa Van De Wyngard, David Wynne, Maya Balakrishnan, Noldy Mardones, Ruth Pfeiffer, Allan Hildesheim, Catterina Ferreccio, Jill Koshiol. Inter-observer agreement in ultrasound-detected steatotic liver in the Chile Biliary Longitudinal Study (BiLS) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6083.

A Recording Method for Sixteen Nonadult Muscle Entheses

ABSTRACT Bioarchaeology lacks a system for recording the morphology of muscle and ligament attachment sites, called entheses, in growing individuals. Such information is useful in investigating factors that affect bone growth and development, including sex, age, puberty, pathology, and activity. This paper presents a standardized recording method for nonadult entheses based on 29 archaeological individuals of archivally known sex and age-at-death, ranging from two to 17 years. This paper (a) assesses the range of osseous changes of 16 entheses in the upper and lower limbs of growing individuals, and (b) presents a scoring method for each enthesis, which is evaluated through inter-and intra-observer comparisons. Nonadult entheses show a wide range of morphological variation. Method reproducibility is established. This method will allow researchers to further investigate factors affecting bone development in nonadult skeletal remains.

Precision of CT-derived alveolar recruitment assessed by human observers and a machine learning algorithm in moderate and severe ARDS

BackgroundAssessing measurement error in alveolar recruitment on computed tomography (CT) is of paramount importance to select a reliable threshold identifying patients with high potential for alveolar recruitment and to rationalize positive end-expiratory pressure (PEEP) setting in acute respiratory distress syndrome (ARDS). The aim of this study was to assess both intra- and inter-observer smallest real difference (SRD) exceeding measurement error of recruitment using both human and machine learning-made lung segmentation (i.e., delineation) on CT. This single-center observational study was performed on adult ARDS patients. CT were acquired at end-expiration and end-inspiration at the PEEP level selected by clinicians, and at end-expiration at PEEP 5 and 15 cmH2O. Two human observers and a machine learning algorithm performed lung segmentation. Recruitment was computed as the weight change of the non-aerated compartment on CT between PEEP 5 and 15 cmH2O.ResultsThirteen patients were included, of whom 11 (85%) presented a severe ARDS. Intra- and inter-observer measurements of recruitment were virtually unbiased, with 95% confidence intervals (CI95%) encompassing zero. The intra-observer SRD of recruitment amounted to 3.5 [CI95% 2.4–5.2]% of lung weight. The human–human inter-observer SRD of recruitment was slightly higher amounting to 5.7 [CI95% 4.0–8.0]% of lung weight, as was the human–machine SRD (5.9 [CI95% 4.3–7.8]% of lung weight). Regarding other CT measurements, both intra-observer and inter-observer SRD were close to zero for the CT-measurements focusing on aerated lung (end-expiratory lung volume, hyperinflation), and higher for the CT-measurements relying on accurate segmentation of the non-aerated lung (lung weight, tidal recruitment…). The average symmetric surface distance between lung segmentation masks was significatively lower in intra-observer comparisons (0.8 mm [interquartile range (IQR) 0.6–0.9]) as compared to human–human (1.0 mm [IQR 0.8–1.3] and human–machine inter-observer comparisons (1.1 mm [IQR 0.9–1.3]).ConclusionsThe SRD exceeding intra-observer experimental error in the measurement of alveolar recruitment may be conservatively set to 5% (i.e., the upper value of the CI95%). Human–machine and human–human inter-observer measurement errors with CT are of similar magnitude, suggesting that machine learning segmentation algorithms are credible alternative to humans for quantifying alveolar recruitment on CT.

Classifying Bone Loss in Failed Stemmed Total Knee Arthroplasty: Determining Reliability

BackgroundFailed stemmed total knee arthroplasty (TKA) components present with varying degrees of bone loss and technical challenges. A classification system has been proposed based upon metaphyseal bone loss and diaphyseal cortical integrity. A validation study was performed to determine interobserver and intraobserver reliability at multiple institutions and with different levels of training. MethodsAn online survey with digital anteroposterior and lateral radiographs was sent to 5 arthroplasty surgeons and 5 adult reconstruction fellows. The survey included 62 cases with stemmed femoral and tibial components, considered failures and pending revision, and scored by each reviewer independently using the classification system. Each case was scored in 2 separate sessions. Interobserver and intraobserver reliability was assessed using the intraclass correlation coefficient (ICC). ResultsInterobserver grading for both the femur (0.69) and tibia (0.72) showed strong reliability among the attendings and fellows, with slightly stronger reliability in tibia cases. The intraclass correlation coefficient (ICC) for attendings and fellows was similar overall, demonstrating consistency of the grading regardless of training level. Intraobserver comparisons showed a strong ICC for attendings and fellows in femoral cases, while fellows had near-perfect ICC in tibia cases. Across all reviewers there was on average 93% agreement within 1 grade per case with the majority of the discrepancy occurring at the metaphyseal-diaphyseal junction. ConclusionThis classification demonstrated overall strong interobserver and intraobserver reliability, with 93% agreement within 1 grade of bone loss. With further education, this classification system can ultimately be used to standardize the degree of bone loss in failed stemmed components and help with preoperative planning.

How reproducible are clinical measurements in robotic knee surgery?

PurposeRobotic-assisted surgery has been recently introduced to improve biomechanical restoration, and thus better clinical and functional outcomes, after knee joint arthroplasty operations. Robotic-assisted uni-compartmental knee arthroplasty (UKA) aims indeed to improve surgical bone resection and alignment accuracy, optimized component positioning and knee balancing, relying on a series of calibration measurements performed during the surgery. These advantages focus therefore on improving the reproducibility of UKA surgeries, reducing (if not eliminating) eventual differences among high- and low-volume surgeons.The purpose of this study is to investigate and quantify the reproducibility of in-vivo measurements performed with a robotic system: the intra- and inter-observer variability of a series of measurements was therefore analyzed and compared among differently experienced operators.MethodsFive patients were analyzed and underwent robotic-assisted UKA using a semi-active robotic system.Three different observers with different experience levels were involved to independently perform the measurements of two parameters of the preoperative knee (Hip-Knee-Ankle angle [HKAa], Internal-External Rotation) at different degrees of knee flexion. Inter-observer and intra-observer comparisons were performed.ResultsThe average variability in the measurements obtained from the intra-observer and inter-observer comparisons were always < 0.68° for HKAa and < 2.59° for internal-external rotation, and the ICCs showed excellent agreement (> 0.75) for most cases and good agreement (> 0.60) in the remaining ones.ConclusionThis study demonstrated high reproducibility of the measurements obtainable in clinical environment with the robotic system. The inter-observer results furthermore showed that the level of confidence with the robotic system is not significantly influencing the measurement.

Inter and Intraobserver Variation in Interpretation of Fecal Loading on Abdominal Radiographs.

The current gold standard for the diagnosis of functional constipation is the ROME IV criteria. European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and North American Society for Pediatric Gastroenterology, Hepatology & Nutrition (NASPGHAN) guidelines do not support the use of abdominal X-rays in establishing the diagnosis of constipation. Despite these recommendations, abdominal radiography is frequently performed to diagnose constipation. The objective of our study is to evaluate inter and intraobserver variation in interpretation of fecal loading on abdominal radiographs. Electronic records of 100 children seen in the emergency room for gastrointestinal symptoms who had an abdominal radiograph performed were included. Four physicians from each specialty including gastroenterology, radiology, and emergency medicine interpreted the radiographs independently. Initially, subjective interpretations, followed by interpretations for intraobserver variation were obtained. Subsequently, all physicians were trained and asked to score the X-rays objectively using Barr and Blethyn scoring systems. Consistency between inter and intraobserver ratings of radiographic interpretation was evaluated using the Kappa coefficient ( k ) which ranges from 0 (no agreement) to 1.0 (perfect agreement). For subjective interpretations, k values showed a fixed margin k of 0.18 indicating poor agreement among 12 observers. Intraobserver k to look for reproducibility showed significant variability ranging from 0.08 (poor) to 0.61 (fair) agreement. Objective scoring results for Blethyn showed a k of 0.14 indicating poor agreement among 12 providers. Reliability and reproducibility of X-rays for diagnosis and grading of constipation is questionable given poor to fair agreement for both inter and intraobserver comparisons. Our study supports the current recommendation of ESPGHAN and NASPGHAN to not use abdominal X-rays to diagnose constipation.

Noninvasive Assessment of Left Ventricular Pressure-Volume Relations: Inter- and Intraobserver Variability and Assessment Across Heart Failure Subtypes

A novel method to derive pressure-volume (PV) loops noninvasively from cardiac magnetic resonance images has recently been developed. The aim of this study was to evaluate inter- and intraobserver variability of hemodynamic parameters obtained from noninvasive PV loops in healthy controls, subclinical diastolic dysfunction (SDD), and patients with heart failure with preserved ejection fraction, mildly reduced ejection fraction, and reduced ejection fraction. We included 75 subjects, of whom 15 were healthy controls, 15 subjects with SDD (defined as fulfilling 1 to 2 echocardiographic criteria for diastolic dysfunction), and 15 patients with preserved ejection fraction, 15 with mildly reduced ejection fraction, and 15 with reduced ejection fraction. PV loops were computed using time-resolved left ventricular volumes from cardiac magnetic resonance images and a brachial blood pressure. Inter- and intraobserver variability and intergroup differences of PV loop-derived hemodynamic parameters were assessed. Bias was low and limits of agreement were narrow for all hemodynamic parameters in the inter- and intraobserver comparisons. Interobserver difference for stroke work was 2 ± 9%, potential energy was 4 ± 11%, and maximal ventricular elastance was -4 ± 7%. Intraobserver for stroke work was -1 ± 7%, potential energy was 3 ± 4%, and maximal ventricular elastance was 1 ± 5%. In conclusion, this study presents a fully noninvasive left ventricular PV loop analysis across healthy controls, subjects with SDD, and patients with heart failure with preserved or impaired systolic function. In conclusion, the method for PV loop computation from clinical-standard manual left ventricular segmentation was rapid and robust, bridging the gap between clinical and research settings.

Robustness and reproducibility of radiomics in T2 weighted images from magnetic resonance image guided linear accelerator in a phantom study

PurposeQuantitative radiomics features extracted from medical images have been shown to provide value in predicting clinical outcomes. The study for robustness and reproducibility of radiomics features obtained with magnetic resonance image guided linear accelerator (MR-Linac) is insufficient. The objective of this work was to investigate the stability of radiomics features extracted from T2-weighted images of MR-Linac for five common effect factors. Materials and methodIn this work, ten jellies, five fruits/vegetables, and a dynamic phantom were used to evaluate the impact of test–retest, intraobserver, varied thicknesses, radiation, and motion. These phantoms were scanned on a 1.5 T MRI system of MR-Linac. For test–retest data, the phantoms were scanned twice with repositioning within 15 min. To assess for intraobserver comparison, the segmentation of MR images was repeated by one observer in a double-blind manner. Three slice thicknesses (1.2 mm, 2.4 mm, and 4.8 mm) were used to select robust features that were insensitive to different thicknesses. The effect of radiation on features was studied by acquiring images when the beam was on. Common movement images of patients during radiotherapy were simulated by a dynamic phantom with five motion states to study the motion effect. A total of 1409 radiomics features, including shape features, first-order features, and texture features, were extracted from the original, wavelet, square, logarithmic, exponential and gradient images. The robustness and reproducibility features were evaluated using the concordance correlation coefficient (CCC). ResultThe intraobserver group had the most robust features (936/1079, 86.7%), while the group of motion effects had the lowest robustness (56/936, 6.0%), followed by the group of different thickness cohorts (374/936, 40.0%). The stability of features in the test–retest and radiation groups was 1072 of 1312 (81.7%) and 810 of 936 (86.5%), respectively. Overall, 25 of 1409 (2.4%) radiomics features remained robust in all five tests, mostly focusing on the image type of the wavelet. The number of stable features extracted from when the beam was on was less than that extracted when the beam was off. Shape features were the most robust of all of the features in all of the groups, excluding the motion group. ConclusionCompared with other factors fewer features remained robust to the effect of motion. This result emphasizes the need to consider the effect of respiration motion. The study for T2-weighted images from MR-Linac under different conditions will help us to build a robust predictive model applicable for radiotherapy.

In vivo Imaging of Retina and Choroid in Guinea Pigs.

Purpose: To evaluate the feasibility of in-vivo imaging of the retina and choroid using spectral domain optical coherence tomography (OCT) in guinea pigs.Methods: The study included 19 pigmented guinea pigs (age: 3–4 weeks) which underwent sonographic axial length measurements and OCT imaging. At study end, the animals were sacrificed and histomorphometric examinations of the retina and choroid were performed. We assessed the reproducibility of the OCT measurements and compared in-vivo measurements to histomorphometric data.Results: The mean thickness of the retina and choroid near the optic nerve head was 175.6 ± 25.8 and 63.4 ± 16.5 μm, respectively, and mean Bruch's membrane opening (BMO) diameter was 831 ± 121 μm. The intra-observer comparison of measurements of retinal thickness (intraclass correlation coefficient (ICC) = 0.92, 95% CI: 0.86–0.96; P < 0.001), choroidal thickness (ICC = 0.92, 95% CI: 0.86–0.96; P < 0.001), and BMO diameter (ICC = 0.92, 95% CI: 0.86–0.96; P < 0.001) showed a high correlation. A high agreement was present also for the inter-observer reproducibility of the measurements of retinal thickness (Pearson correlation coefficient (R) = 0.98; P < 0.001), choroidal thickness (R = 0.96; P < 0.001), and BMO diameter (R = 0.98; P < 0.001). The Bland-Altman plots showed that 2.6% (1/38), 5.3% (2/38), and 7.9% (3/38) of the measurement points of retinal thickness, choroidal thickness and BMO diameter, respectively, were located outside of the 95% limits of agreement. The OCT-based thickness measurements of retina and choroid were significantly higher than those measured by histomorphometry (both P-values <0.01).Conclusion: OCT-based in-vivo morphometric imaging of the retina and choroid in guinea pigs is feasible with an acceptable intra-observer repeatability and inter-observer reproducibility.

Reliability and reproducibility of measurements in para-sagittal planes on sub-axial cervical vertebral bodies: a morphometric study of endplates in three-dimensional models

BackgroundDimensional measurements have been implemented on a variety of entities in morphological studies of the sub-axial cervical vertebral endplate. Despite great progress, little information between the mid-sagittal plane and bilateral uncinate processes has been acquired due to the lack of a reliable method to determine the para-sagittal planes. Also, few studies of this region are available. We proposed a new approach to defining the para-sagittal planes on a 3D cervical vertebral body model; in this approach, dimensions can be measured in a specific plane. The aim of this study was to assess the inter-observer and intra-observer reliability of the measurements in different sagittal planes on sub-axial cervical vertebral endplates of 3D models.MethodsWe established mid-sagittal and bilateral quarter para-sagittal planes on the 3D model of a sub-axial cervical vertebral body based on landmarks labeled on the surface. By intersecting the vertebral body with the planes, three curves located at the three para-sagittal planes were generated. Linear dimensions were measured on every curve by two observers separately, and in total, 24 sub-axial cervical spines were included in the study. The first observer (O1) performed the procedure twice with an interval of 2 weeks. The paired t test, Wilcoxon matched-pairs signed-rank test and the interclass correlation coefficient (ICC) were employed to evaluate the inter- and intra-observer reliability of the proposed method.ResultsThere were no significant differences in most intra- and inter-observer comparisons, and higher non-significant proportions were found in the intra-observer comparisons than in comparisons between different observers. The interclass correlation coefficients (ICCs) in the measurements were excellent (> 0.75) in most circumstances, and the values in intra-observer comparisons were higher than those in inter-observer comparisons.ConclusionsIn this study, we proposed an approach to determine the bilateral quarter para-sagittal planes in a 3D cervical vertebral body model; the results demonstrated that the method is reproducible with high intra- and inter-observer agreement.

Electrical stimulation to clinically identify position of the lingual nerve: results of 50 subjects with reliability and correlation with MRI

PurposeRecently we described mapping of the lingual nerve clinically in patients using electrical nerve stimulation. This paper reports results of a larger study with inter- and intra-observer reliability and comparison with positional measurements from magnetic resonance imaging (MRI).MethodsIn 50 healthy participants, measurements were taken when subjects felt a tingling sensation in the tongue induced by a stimulation probe over the lingual nerve. Three positions were measured in relation to the third molar. Measurement reliability was tested for both inter-observer and intra-observer agreement and positional data of the lingual nerve measured clinically was also compared with nerve position as measured from MRI scans.ResultsOut of 50 participants, 96 nerves (49 = left/47 = right) were included in the study. The lingual nerve was identified in 90% (87) of this sample. The mean of height of the nerve in points A, B and C were 9.64 mm, 10.77 mm and 12.34 respectively. Inter-and intra-observer agreement was considered to be good to excellent (ICC = 0.8–0.96). Agreement between nerve mapping measured values and MRI measured values was good (ICC < 0.6).ConclusionThis technique may prove useful for the clinical determination of lingual nerve position prior to procedures in the third molar region.

Fully digital pathology laboratory routine and remote reporting of oral and maxillofacial diagnosis during the COVID-19 pandemic: a validation study.

The role of digital pathology in remote reporting has seen an increase during the COVID-19 pandemic. Recently, recommendations had been made regarding the urgent need of reorganizing head and neck cancer diagnostic services to provide a safe work environment for the staff. A total of 162 glass slides from 109 patients over a period of 5 weeks were included in this validation and were assessed by all pathologists in both analyses (digital and conventional) to allow intraobserver comparison. The intraobserver agreement between the digital method (DM) and conventional method (CM) was considered almost perfect (κ ranged from 0.85 to 0.98, with 95% CI, ranging from 0.81 to 1). The most significant and frequent disagreements within trainees encompassed epithelial dysplasia grading and differentiation among severe dysplasia (carcinoma in situ) and oral squamous cell carcinoma. The most frequent pitfall from DM was lag in screen mirroring. The lack of details of inflammatory cells and the need for a higher magnification to assess dysplasia were pointed in one case each. The COVID-19 crisis has accelerated and consolidated the use of online meeting tools, which would be a valuable resource even in the post-pandemic scenario. Adaptation in laboratory workflow, the advent of digital pathology and remote reporting can mitigate the impact of similar future disruptions to the oral and maxillofacial pathology laboratory workflow avoiding delays in diagnosis and report, to facilitate timely management of head and neck cancer patients. Graphical abstract

Reproducibility of Left Ventricular CINE DENSE Strain in Pediatric Subjects with Duchenne Muscular Dystrophy.

Cardiomyopathy is the leading cause of mortality in boys with Duchenne muscular dystrophy (DMD). Left ventricular (LV) peak mid-wall circumferential strain (Ecc) is a sensitive early biomarker for evaluating both the subtle and variable onset and the progression of cardiomyopathy in pediatric subjects with DMD. Cine Displacement Encoding with Stimulated Echoes (DENSE) has proven sensitive to changes in Ecc, but its reproducibility has not been reported in a pediatric cohort or a DMD cohort. The objective was to quantify the intra-observer repeatability, and intra-exam and inter-observer reproducibility of global and regional Ecc derived from cine DENSE in DMD patients (N = 10) and age-and sex-matched controls (N = 10). Global and regional Ecc measures were considered reproducible in the intra-exam, intra-observer, and inter-observer comparisons. Intra-observer repeatability was highest, followed by intra-exam reproducibility and then inter-observer reproducibility. The smallest detectable change in Ecc was 0.01 for the intra-observer comparison, which is below the previously reported yearly decrease of 0.013 ± 0.015 in Ecc in DMD patients.

Feasibility of Cardiovascular Four-dimensional Flow MRI during Exercise in Healthy Participants.

To explore the feasibility of using four-dimensional (4D) flow MRI to quantify blood flow and kinetic energy (KE) in the heart during strenuous exercise. For this prospective study, cardiac 4D flow MRI was performed in 11 healthy young adult participants (eight men, three women; mean age, 26 years ± 1 [standard deviation]) at rest and during exercise with an MRI-compatible exercise stepper between March 2016 and July 2017. Flow was measured in the ascending aorta (AAo) and main pulmonary artery (MPA). KE was quantified in the left and right ventricle. Significant changes in flow and KE during exercise were identified by using t tests. Repeatability was assessed with inter- and intraobserver comparisons and an analysis of internal flow consistency. Nine participants successfully completed both rest and exercise imaging. Internal flow consistency analysis in systemic and pulmonary circulation showed average relative differences of 10% at rest and 16% during exercise. For flow measurements in the AAo and MPA, relative differences between observers never exceeded 6% in any vessel and showed excellent correlation, even during exercise. Relative differences were increased for KE, typically on the order of 30%, with poor interobserver correlation between measurements. Four-dimensional flow MRI can quantify increases in flow in the AAo and MPA during strenuous exercise and is highly repeatable. KE had reduced repeatability because of suboptimal segmentation methods and requires further development before clinical implementation. Supplemental material is available for this article. © RSNA, 2020See also the commentary by Markl and Lee in this issue.

Classifications in Brief: AO Thoracolumbar Classification System.

Classifications in Brief: AO Thoracolumbar Classification System.

Comparison of Fundus Biomicroscopy Examination of the Optic Nerve Head with and without Mydriasis

Background: Notwithstanding the significant advances in automated imaging techniques in the past 2 decades, subjective evaluation of the optic disc still remains an important part of glaucoma propaedeutic. In places with limited resources and a high demand for ophthalmic care, anatomical evaluation of glaucoma cases often relies solely on slit-lamp-based fundus biomicroscopic examination, which is frequently performed without mydriasis. Objective: The aim of this study was to compare metrics related to fundus biomicroscopy examination of the optic nerve head and peripapillary retinal nerve fiber layer (pRNFL) with and without mydriasis. Material and Methods: Healthy individuals, patients with early glaucoma, and glaucoma suspects were prospectively enrolled. Patients were examined before and after mydriasis by three glaucoma specialists, who estimated patients’ vertical cup-to-disc ratio (CDR) and evaluated the presence of glaucomatous signs: laminar dot sign, disc hemorrhage, disc saucering, disc notching, peripapillary atrophy, localized pRNFL defect, and loss of the ISNT pattern. Main outcome measures were the intra-observer comparison, the inter-observer agreement, and the abilities to identify glaucomatous signs before and after mydriasis. Results: Thirty patients (60 eyes) were enrolled (mean age, 62.3 ± 11.6 years). Considering the evaluation of the three examiners, the mean vertical CDR increased from 0.41 to 0.44 (p = 0.02), and the median of the coefficient of variation of the measures was reduced from 0.24 to 0.11 (p = 0.01) after mydriasis. Regarding the inter-observer agreement evaluation, the kappa coefficient values ranged from 0.64 to 0.72 before mydriasis and from 0.71 to 0.77 after mydriasis. Dot sign and disc notching were better identified through fundoscopic examination with mydriasis compared to the nonmydriatic examination (p < 0.01). Conclusion: Our results suggest that fundus biomicroscopy should be performed with mydriasis whenever possible, as it yells a better intra- and inter-observer agreement and improves the detection of glaucomatous signs. Moreover, examiners seem to underestimate CDR values without mydriasis. Further investigation is warranted to validate these findings by general ophthalmologists and in different populations.

Reliability Analyses of Radiographic Measures of Vertebral Body Height Loss in Thoracolumbar Burst Fractures

In thoracolumbar (TL) burst fractures, vertebral body height loss (VBHL) indicates the degree of instability and constitutes one of the decision criteria for surgical treatment. However, the relative reliability and variability of different measurement techniques for VBHL are unknown. We compared the reliability of different methods used to assess VBHL. A total of 144 patients with TL burst fractures were included, and lateral radiographs were taken twice at an interval of 2 weeks, which were examined by 3 observers. The measurement methods used included the anterior/posterior vertebral body height compression ratio (APCR), anterior height compression percentage (AHCP), and anterior/posterior vertebral body height compression ratio percentage. To compare the accuracy of measurements according to vertebral degeneration, subjects were divided into 2 groups based on the median age of 50 years. In intraobserver comparisons, the APCR method showed a higher inter- and intraclass correlation coefficient (ICC) (>0.714) compared with the other methods. In interobserver comparisons, the ICC of the APCR (>0.793) was excellent. In intraobserver comparisons of the aged >50-years group, only the APCR method showed an excellent ICC (>0.753), whereas the AHCP method showed a fair to good ICC, and the anterior/posterior vertebral body height compression ratio percentage method had the lowest ICC. In interobserver comparisons of the aged >50-years group, the APCR and AHCP methods showed excellent ICCs. In the aged ≤50-years group, all 3 methods showed similar fair to good ICC values. Based on comparative reliability analyses, we recommend the APCR method as the first-line technique and the AHCP as an alternative technique for measuring VBHL in TL burst fractures.

Automated 3-Dimensional Magnetic Resonance Imaging Allows for Accurate Evaluation of Glenoid Bone Loss Compared With 3-Dimensional Computed Tomography

To evaluate clinical measurements of glenoid bone loss based on 3-dimensional (3D) computed tomography (CT) and automatically segmented 3D reconstructions from Dixon fat-water magnetic resonance (MR) imaging. Available CT and MR studies from 16 patients with recurrent anterior shoulder instability were retrospectively reviewed. Three-dimensional reconstructions were formed independently by 2 observers using freely available software and a simple threshold-based segmentation (3D Slicer, version 4.8.0; http://www.slicer.org). Bone loss was estimated with the perfect-circle method. Intra-user and interuser reproducibility was determined with intraclass correlation coefficients. Bland-Altman plots were used to evaluate the similarity between imaging modalities. Differences between MR and CT estimates of bone loss ranged from 0% to 6%. The individual intraclass correlation coefficients showed good to excellent reliability, with intraobserver comparisons between MR- and CT-based bone loss estimates ranging from 0.94 to 0.99. Bland-Altman plots showed 95% confidence intervals from -5% to 6% for differences between MR and CT estimates, with 88% of all measurements (42 of 48) showing a less than 2% difference between MR and CT estimates. The described methodology for obtaining an MR-based 3D reconstruction of the glenoid can evaluate glenoid bone loss similarly to the performance of a 3D CT reconstruction. The results may allow surgeons to simplify the preoperative imaging protocol for patients with recurrent shoulder stabilization and limit the number of shoulder CT scans. Level III, retrospective therapeutic trial.

Breast Cancer Prognostic Factors in the Digital Era: Comparison of Nottingham Grade using Whole Slide Images and Glass Slides

Background: To assess reproducibility and accuracy of overall Nottingham grade and component scores using digital whole slide images (WSIs) compared to glass slides. Methods: Two hundred and eight pathologists were randomized to independently interpret 1 of 4 breast biopsy sets using either glass slides or digital WSI. Each set included 5 or 6 invasive carcinomas (22 total invasive cases). Participants interpreted the same biopsy set approximately 9 months later following a second randomization to WSI or glass slides. Nottingham grade, including component scores, was assessed on each interpretation, providing 2045 independent interpretations of grade. Overall grade and component scores were compared between pathologists (interobserver agreement) and for interpretations by the same pathologist (intraobserver agreement). Grade assessments were compared when the format (WSI vs. glass slides) changed or was the same for the two interpretations. Results: Nottingham grade intraobserver agreement was highest using glass slides for both interpretations (73%, 95% confidence interval [CI]: 68%, 78%) and slightly lower but not statistically different using digital WSI for both interpretations (68%, 95% CI: 61%, 75%; P = 0.22). The agreement was lowest when the format changed between interpretations (63%, 95% CI: 59%, 68%). Interobserver agreement was significantly higher (P < 0.001) using glass slides versus digital WSI (68%, 95% CI: 66%, 70% versus 60%, 95% CI: 57%, 62%, respectively). Nuclear pleomorphism scores had the lowest inter- and intra-observer agreement. Mitotic scores were higher on glass slides in inter- and intra-observer comparisons. Conclusions: Pathologists’ intraobserver agreement (reproducibility) is similar for Nottingham grade using glass slides or WSI. However, slightly lower agreement between pathologists suggests that verification of grade using digital WSI may be more challenging.