Inter-Observer Variability in the Detection and Interpretation of Chest X-Ray Anomalies in Adults in an Endemic Tuberculosis Area

Purpose: To assess the inter-observer agreement in reading adults chest radiographs (CXR) and determine the effectiveness of observers in radiographic diagnosis of pulmonary tuberculosis (PTB) in a tuberculosis endemic area. Methods: A quasi-observational study was conducted in the Pneumology Department of Yaounde Jamot Hospital (Cameroon) from January to March 2014. This included six observers (two chest physicians, two radiologists, two end-training residents in medical imaging) and 47 frontal CXRs (4 of diffuse interstitial lung disease, 6 normal, 7 of lung cancers, 7 of bacterial pneumonia, 23 of PTB). The sample size was calculated on the basis of an expected 0.47 Kappa with a spread of 0.13 (α = 5%, CI = 95%) for six observers and five diagnostic items. The analysis of concordance was focused on the detection of nodules, cavitary lesions, pleural effusion, adenomegaly and diagnosis of PTB and lung cancer. These intervals of kappa coefficient were considered: discordance (0.81). Results: The average score for the detection of caverns was the highest (58.3%) followed by that of the correct diagnosis of tuberculosis (49.3%). Pneumologists had the highest proportions of correct diagnosis of tuberculosis (69.6% and 73.9%) and better inter-observer agreement (k = 0.71) for PTB diagnosis. Observers were more in agreement for the detection of nodules (0.32 - 0.74), adenomegalies (0.43 - 0.69), and for the diagnosis of cancer (0.22 - 1) than for the diagnosis of tuberculosis (0.19 - 0.71). Disagreements were more frequent for the detection of pleural effusions (-0.08 - 0.73). Conclusion: The inter-observer agreement varies with the type of lesions and diagnosis. Pneumologists were most effective for the diagnosis of pulmonary tuberculosis. Observers were more in agreement for the detection of nodules and the diagnosis of cancer than for the diagnosis of pulmonary tuberculosis.

A Technical Note: Inter-Observer and Inter-Modality Variability of Cone-Beam Computed Tomography (CBCT) and Ultrasound (US) in Stereotactic Body Radiotherapy for Kidney Cancer

Introduction: To investigate the inter-observer and inter-modality variabilities of two imaging guided equipments—cone-beam computed tomography (CBCT) and ultrasound (US) in kidney stereotactic body radiotherapy. Methods: A renal metastasis case implanted with three gold anchor fiducial markers was firstly scanned by US to acquire a 3-dimension US image and followed by 4-dimension CBCT in every fraction. Seven observers retrospectively registered the pre-treatment images with the corresponding reference images based on the gold markers. Registration uncertainty of the observers between two imaging modalities was evaluated. Results: The uncertainties over whole treatment course in CBCT were 0.88 mm, 1.94 mm and 0.86 mm in lateral, longitudinal and vertical directions respectively;while 0.8 mm, 0.97 mm and 1.36 mm were found in US. Conclusion: The greatest uncertainty was found in longitudinal direction in CBCT due to the fact that the respiration motion is the most rigorous in cranial-caudal direction. In US, since the probe was hold almost in upright position, the strong echo in vertical direction was attributed to the greatest uncertainty for such direction.

Dosimetric Effects Due to Inter-Observer Variability of Organ Contouring When Utilizing a Knowledge-Based Planning System for Prostate Cancer

Purpose: Radiotherapy is a widely accepted standard of care for early-stage prostate cancer, and it is believed that the plan quality and treatment outcome are associated with contour accuracy of both the target and organs-at-risk (OAR). The purposes of this study are to 1) assess geometric and dosimetric uncertainties due to inter-observer contour variabilities and 2) evaluate the effectiveness of geometric indicators to predict target dosimetry in prostate radiotherapy. Methods: Twenty prostate patients were selected for this retrospective study. Five experienced clinicians created unique structure sets containing prostate, seminal vesicles, bladder, and rectum for each patient. A fully automated script and knowledge-based planning routine were utilized to create standardized and unbiased plans that could be used to evaluate changes in isodose distributions due to inter-observer variability in structure segmentation. Plans were created on a “gold-standard” structure set, as well as on each of the user-defined structure sets. Results: Inter-observer variability of contours during structure segmentation was very low for clearly defined organs such as the bladder but increased for organs without well-defined borders (prostate, seminal vesicles, and rectum). For plans generated with the user-defined structure sets, strong/moderate correlations were observed between the geometric indicators for target structure agreement and target coverage for both low-risk and intermediate-risk patient groups, while OAR indicators showed no correlation to final dosimetry. Conclusions: Target delineation is crucial in order to maintain adequate dosimetric coverage regardless of the associated inter-observer uncertainties in OAR contours that had a limited impact upon final dosimetry.

Inter-Observer Variability in the Interpretation of 68Ga-PSMA PET-CT Scan according to PROMISE Criteria

Aims & Objectives: Aim of the study was to evaluate inter-observer variability in interpretation of Gallium-68 labeled Prostate Specific Membrane Antigen sub-type 11 (68Ga-PSMA-11) Positron Emission Tomography-Computed Tomography PET_CT scan according to Prostate Cancer Molecular Imaging Standardized Evaluation (PROMISE) criteria. Method and Materials: Forty-four consecutive patients of prostate cancer were prospectively studied between the duration of January 2021 to June 2021 at Institute of Nuclear Medicine and Oncology (INMOL), Lahore. All PET-CT scans were assessed by a researcher and 3 nuclear physicians and divided into two groups, interpreted in two phases. In the first phase, each group independently evaluated the scans while in the second phase, a consensus meeting was held and all the cases with discordance were discussed. Cohen’s Kappa test was used to measure interobserver variability with the cut-off of K’s alpha Results: The study showed 41 out of 44 scans with positive PSMA findings while 03 scans were negative for any PSMA avid disease. In the first phase of image analysis, the level of agreement was slight in T stage (Kappa = 0.068, p = 0.65), moderate in the miN stage (Kappa = 0.46, p = 0.02) and substantial in miM stage (Kappa = 0.77, p ≤ 0.001) was seen. For PSMA score, overall agreement was substantial agreement (Kappa = 0.64, p Conclusion: Remarkable inter-observer agreement was seen in PROMISE criteria.

Inter-observer Reliability of Indicators and Decision of Pattern Identification Using Diagnostic Flowchart with Traditional Korean Medicine

Objective： To evaluate the consistency of patterns and pattern identification（PI）, and the improvement in the diagnosis of blood stasis after the standard operating procedures（SOPs） were enhanced by using a diagnostic flowchart. Methods： A total of 358 subjects who were admitted by the Jaseng Hospital of Korean Medicine between June 2013 and December 2014 were included in the study. Each patient was independently diagnosed by two experts from the same department. In 2014, the SOPs included the use of a diagnostic flowchart for each indicator. Inter-observer consistency was assessed by simple percent agreement and by the kappa and AC1 statistics. Results： The improvements in inter-observer agreement for the indicators（for al patients） and PI were greater in 2014 than in 2013. In 2013, the j-value measure of agreement between the two experts ranged from ＂poor＂（κ=–0.051） to ＂good＂（κ=0.968）. The AC1 measure of agreement between the experts was generally high for the indicators and ranged from –0.010 to 0.978. In most cases, agreement was considerably lower when it was assessed by the j-values compared with the AC1 values. In 2014, the j-value measure of agreement on the indicators（for the subjects） general y ranged from poor to good, with the values ranging from –0.007 to 0.994. Moreover, the AC1 measure of agreement between the experts was general y high for al of the indicators and ranged from ＂moderate＂（AC1=0.408） to ＂excel ent＂（AC1=0.996）. Conclusions： In four examinations, there was moderate agreement between the clinicians on the PI indicators of blood stasis. To improve clinician consistency（e.g., in the diagnostic criteria used）, it is necessary to analyse the reasons for inconsistency and to improve clinician training.（Trial registration No. KCT0000916）

Predictive findings forHelicobacter pylori-uninfected, -infected and -eradicated gastric mucosa: Validation study

AIM:To validate the usefulness of screening endoscopy findings for predictingHelicobacter pylori (H. pylori) infection status. METHODS:H. pylori infection status was determined by histology, serology, and the urea breast test in 77 consecutive patients who underwent upper endoscopy. Based on the findings, patients were categorized as H. pylori -uninfected, -infected, or -eradicated cases. Using six photos of certain sites in the stomach per case, we determined the presence or absence of the following endoscopic findings:regular arrangement of collecting venules (RAC), linear erythema, hemorrhage, fundic gland polyp (FGP), atrophic change, rugal hyperplasia, edema, spotty erythema, exudate, xanthoma, and mottled patchy erythema (MPE). The diagnostic odds ratio (DOR) and inter-observer agreement (Kappa value) for these 11 endoscopic findings used in the determination of H. pylori infection status were calculated. RESULTS:Of the 77 patients [32 men and 45 women; mean age (SD), 39.7 (13.4) years] assessed, 28 were H. pylori uninfected, 28 were infected, and 21 were eradicated. DOR values were significantly high (< 0.05) for the following H. pylori cases:uninfected cases with RAC (11.5), linear erythema (24.5), hemorrhage (4.1), and FGP (34.5); for infected cases with atrophic change (8.67), rugal hyperplasia (15.8), edema (14.2), spotty erythema (11.5), and exudate (3.52); and for eradicated cases with atrophic change (32.4) and MPE (103.0). Kappa values were excellent for FGP (0.93), good for RAC (0.63), hemorrhage (0.79), atrophic change (0.74), and MPE (0.75), moderate for linear erythema (0.51), rugal hyperplasia (0.49), edema (0.58), spotty erythema (0.47), and exudate (0.46), and poor for xanthoma (0.19). CONCLUSION:The endoscopic findings of RAC, hemorrhage, FGP, atrophic change, and MPE will be useful for predicting H. pylori infection status.

Research on consistency of identifying solitary pulmonary masses with CT

Objective：To research on consistency of identifying solitary pulmonary masses with CT. Methods：Three observers with different working backgrounds in imaging diagnosis individually interpreted the same group images of solitary pulmonary mass, by 12 indexes of objective signs. The differences in interpretation resulted in ante- and post-interpretations were assessed by the x^2 test. The agreement of two interpretations from the same observer was confirmed with the kappa test. A double-blind method was adopted for analysis. Results：The agreement rates of ante- and post-interpreting from the three observers were respectively 82.65%（486/588） 80.27%（472/ 588） and 84.86% （499/588） while their interpreting results were generally accordant without significant difference（x^2 = 4.975, df= 2, P= 0.083） however there was difference between the observer 2 and observer 3（x^2 = 4.875, df= 1, P = 0.027）. There were five indexes with k 〉 0.40 of ante- and post-interpreting results of the three observers, including clarity of nodule borderline, presence of sentus, uniformity of density, existence of cavity and calcification in pathological region, among them, the agreement rate of interpreting borderline and cavity was higher（k 〉 0.07）; the blood vessel convergence poorer（0 〈 k ≤ 0.40）; the other six CT signs of interpretation were slightly different. Conclusion：The ability to identify solitary pulmonary mass was inconsistent, and needs to be improved further.

Reproducibility of 3 mm-Slice-Thick Reconstruction of Paranasal Sinus Computed Tomography Scans

Background: After the failure of medical treatment, the surgery of chronic rhinosinusitis (CRS) is planned according to endoscopic and paranasal sinus computed tomography (CT) findings. Objective: The aim of this prospective study was to evaluate whether this study method might be eligible in studies aiming at radiation dose reduction. Sinus CT scans were chosen as a model because of the high variation of the radiological anatomy of surgically important sinonasal structures. We hypothesized that 3 mm-slice-thick reconstruction CT had poor reproducibility. Methods: 59 CRS patients underwent routine multi-detector sinus CT (CTMD). CT3mm was reconstructed from CTMD data-sets. Lund-Mackay (LM) scores and 43 other structural parameters were analyzed blinded. Agreement was studied between CTMD and CT3mm (intra-observer reproducibility), and between three observers (inter-observer reproducibility) by using Cohen’s kappa. Results: The inter-observer agreement was moderate (kappa 0.4 - 0.6, p < 0.01) in the majority of structures of CT3mm scans. The intra-observer reproducibility of CT3mm scans was very good in most structures, however, it was poor in important structures such as frontal and spheno-ethmoid recess, lamina papyracae, and location of optic nerve or anterior ethmoidal artery. The grade of surgeon’s confidence of CT3mm in comparison to CTMD was lower (kappa 0.2 - 0.4, P < 0.05). Conclusion: This methodology might have some use in studies aiming at radiation dose reduction. As was expected, 3 mm-slice-thick reconstruction CT had poor reproducibility and surgeon’s confidence. More recent methods such as cone beam computed tomography scans have nowadays more relevant dose reduction potential.

Reliability of the measurement of glenoid bone defect in anterior shoulder instability

Background:The size of the glenoid bone defect is an important index in selecting the appropriate treatment for anterior shoulder instability.However,the reliability of glenoid bone defect measurement is controversial.The purpose of the present study was to investigate the reliabilities of measurements of the glenoid bone defect on computed tomography and to explore the predisposing factors leading to inconsistency of these measurements.Methods:The study population comprised 69 consecutive patients who underwent surgery for recurrent anterior shoulder dislocation in Peking University Fourth School of Clinical Medicine from March 2016 to January 2017.The glenoid bone defect was measured by three surgeons on‘self-confirmed’and‘designated’3-D en-face views,and repeated after an interval of 3 months.Measurements included the ratio of the defect area to the best-fit circle area,and the ratio of the defect width to the diameter of the best-fit circle.The inter-and intra-observer reliabilities of the measurements were evaluated using intraclass correlation coefficients(ICCs).The maximum absolute inter-and intra-observer differences and the cumulative percentages of cases with inter-and intraobserver differences greater than these respective levels were calculated.Results:Almost all linear defect values were bigger than the areal defect values.The inter-observer ICCs for the areal defect were 0.557 and 0.513 in the‘self-confirmed’group and 0.549 and 0.431 in the‘designated’group.The inter-observer reliabilities for the linear defect were moderate or fair in the‘self-confirmed’group(ICC=0.446,0.374)and‘designated’group(ICC=0.402,0.327).The ICCs for intra-observer measurements were higher than those for inter-observer measurements.The respective maximum interand intra-observer absolute differences were 13.9%and 13.2%in the‘self-confirmed’group,and 15.8%and 9.8%in the‘designated’group.Conclusions:The areal measurement of the glenoid bone defect is more reliable than the linear measurement.The reliability of the glenoid defect areal measurement is moderate or worse,suggesting that a more accurate and objective measurement method is needed in both en-face view and best-fit circle determination.Subjective factors affecting the glenoid bone loss measurement should be minimized.