Impact of cone beam CT on diagnosis of external cervical resorption: the severity of resorption assessed in periapical radiographs and cone beam CT. A prospective clinical study

Objectives: To compare the severity of external cervical resorption (ECR) observed in periapical (PA) images and cone beam CT (CBCT) using the Heithersay classification system and pulp involvement; and to assess inter- and intraobserver reproducibility for three observers. Methods: CBCT examination was performed in 245 teeth (in 190 patients, mean age 40 years, range 12–82) with ECR diagnosed in PA images. Three observers scored the severity of ECR using the Heithersay classification system (severity class 1–4) and pulp involvement (yes/no) in both PA images and CBCT. Percentage concordance and κ-statistics described observer variation in PA images and CBCT for both inter- and intraobserver reproducibility. Results: For all three observers, the ECR score was the same in the two modalities in more than half of cases (average 59%; obs1: 54%, obs2: 63%, obs3: 61%). However, in 38% (obs1: 44%, obs2: 33%, obs3: 36%) of the cases, the observers scored more severe ECR in CBCT than in PA images (p < 0.001). The ECR score changed to a less severe score in CBCT only in 3% (obs1: 1%, obs2: 4%, obs3: 4%). For pulp involvement, 14% (obs1: 7%, obs2: 20%, obs3: 15%) of the cases changed from “no” in PA images to “yes” in CBCT. In general, κ values were higher for CBCT than for PA images for both the Heithersay classification score and pulp involvement. Conclusions: ECR was generally scored as more severe in CBCT than PA images using the Heithersay classification and also more cases had pulp involvement in CBCT.

The reliability of the AOSpine Thoracolumbar Spine Injury Classification System in children: an international validation study

Purpose To evaluate the AOSpine Thoracolumbar Spine Injury Classification System and if it is reliable and reproducible when applied to the paediatric population globally. Methods A total of 12 paediatric orthopaedic surgeons were asked to review MRI and CT imaging of 25 paediatric patients with thoracolumbar spine traumatic injuries, in order to determine the classification of the lesions observed. The evaluators classified injuries into primary categories: A, B and C. Interobserver reliability was assessed for the initial reading by Fleiss’s kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, sub-classification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff’s alpha (αk) along with bootstrapped 95% CIs. A second round of classification was performed one-month later. Intraobserver reproducibility was assessed for the primary classifications using Fleiss’s kappa and sub-classification reproducibility was assessed by Krippendorff’s alpha (αk) along with 95% CIs. Results In total, 25 cases were read for a total of 300 initial and 300 repeated evaluations. Adjusted interobserver reliability was almost perfect (kF = 0.74; 95% CI 0.71 to 0.78) across all observers. Sub-classification reliability was substantial (αk= 0.67; 95% CI 0.51 to 0.81), Adjusted intraobserver reproducibility was almost perfect (kF = 0.91; 95% CI 0.83 to 0.99) for both primary classifications and for sub-classifications (αk = 0.88; 95% CI 0.83 to 0.93). Conclusion The inter- and intraobserver reliability for the AOSpine Thoracolumbar Spine Injury Classification System was high amongst paediatric orthopaedic surgeons. The AOSpine Thoracolumbar Spine Injury Classification System is a promising option as a uniform fracture classification in children. Level of Evidence III

Loco-regional N staging in Rectal Cancer with Magnetic Resonance Imaging: A Study of Inter- and Intra-Observer Variability

Background: Colorectal cancer is one of the most common tumors for both men and women: in the United States, it represents the third leading cause of new cancer cases and cancer-related deaths. The prognosis is directly related to tumor infiltration in the mesorectum and lymph node metastases. In particular, it’s important to define the distance between lymphadenopathy and mesorectal fascia, as this has repercussions on surgical planning. This study aimed to evaluate the agreement among observers with different abdominal MRI expertise and intra-observer reliability in lymph nodes size and feature definition. Methods: In this retrospective study, MRI examinations were performed in 88 patients with rectal adenocarcinoma treated with primary surgery. Four observers, two senior physicians, and two junior physicians, analyzed MRI scans in two sessions 30 days apart and determined the size and morphological pattern of regional lymph nodes. Statistical analysis included the determination of Fleiss kappa (k) coefficient, Cohen's Kappa coefficient, and confidence intervals (CI). Results: The inter-observer reproducibility for MRI N-staging was good among the four physicians (kappa = 0.65; CI 0.45–0.77). Reproducibility between the two senior physicians had a kappa of 0.68 (CI 0.62–1.00), while between the two junior physicians had a kappa of 0.61 (CI 0.33–0.89). Inter-observer reproducibility was excellent for mesorectal, inferior mesenteric, and internal iliac lymph nodes (kappa values of 0.89, 0.82, and 0.80 respectively). For the other two nodal stations (superior and middle rectal lymph nodes, sacral lymph nodes), there was a good interobserver reproducibility (kappa between 0.70 and 0.77).The intra-observer reproducibility of interpretations of the MRI overall N staging progressively decreased among observer B (kappa= 0.85), observer C (kappa= 0.59), and the other two physicians. There was a significant difference in lymph nodes measurements between the first and second sessions in observer A (p ≥ 0.05). Excellent intraobserver reproducibility was found for mesorectal lymph nodes; the lowest intraobserver reproducibility values were found for presacral and lateral sacral lymph nodes.Conclusions: Although the low accuracy of MRI in assessing the involvement of metastatic lymph nodes in rectal cancer, this study demonstrates good interobserver reliability among physicians with different abdominal MRI experiences.

Pelvic incidence and pelvic tilt can be calculated using either the femoral heads or acetabular domes in patients with hip osteoarthritis

Aims The aim of the study was to compare two methods of calculating pelvic incidence (PI) and pelvic tilt (PT), either by using the femoral heads or acetabular domes to determine the bicoxofemoral axis, in patients with unilateral or bilateral primary hip osteoarthritis (OA). Methods PI and PT were measured on standing lateral radiographs of the spine in two groups: 50 patients with unilateral (Group I) and 50 patients with bilateral hip OA (Group II), using the femoral heads or acetabular domes to define the bicoxofemoral axis. Agreement between the methods was determined by intraclass correlation coefficient (ICC) and the standard error of measurement (SEm). The intraobserver reproducibility and interobserver reliability of the two methods were analyzed on 31 radiographs in both groups to calculate ICC and SEm. Results In both groups, excellent agreement between the two methods was obtained, with ICC of 0.99 and SEm 0.3° for Group I, and ICC 0.99 and SEm 0.4° for Group II. The intraobserver reproducibility was excellent for both methods in both groups, with an ICC of at least 0.97 and SEm not exceeding 0.8°. The study also revealed excellent interobserver reliability for both methods in both groups, with ICC 0.99 and SEm 0.5° or less. Conclusion Either the femoral heads or acetabular domes can be used to define the bicoxofemoral axis on the lateral standing radiographs of the spine for measuring PI and PT in patients with idiopathic unilateral or bilateral hip OA. Cite this article: Bone Joint J 2021;103-B(8):1345–1350.

Renal Diffusion-Weighted Imaging in Healthy Dogs: Reproducibility, Test-Retest Repeatability, and Selection of the Optimal b-value Combination

Diffusion-weighted imaging (DWI) magnetic resonance imaging can evaluate alterations in the microstructure of the kidney. The purpose of this study was to assess the apparent diffusion coefficient (ADC) and the intravoxel incoherent motion model (IVIM) parameters of a normal kidney in healthy dogs, to evaluate the effect of b-value combinations on the ADC value, and the reproducibility and test-retest repeatability in monoexponential and IVIM analysis. In this experimental study, the ADC, pure diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (fp) were measured from both kidneys in nine healthy beagles using nine b-values (b = 0, 50, 70, 100, 150, 200, 500, 800, and 1,000 s/mm2) twice with a 1-week interval between measurements. Interobserver and intraobserver reproducibility, and test-retest repeatability of the measurements were calculated. ADC values were measured using 10 different b-value combinations consisting of three b-values each, and were compared to the ADC obtained from nine b-values. All the ADC, D, D*, and fp values measured from the renal cortex, medulla, and the entire kidney had excellent interobserver and intraobserver reproducibility, and test-retest repeatability. The ADC obtained from a b-value combination of 0, 100, and 800 s/mm2 had the highest intraclass correlation coefficient with the ADC from nine b-values. The results of this study indicated that DWI MRI using multiple b-values is feasible for the measurement of ADC and IVIM parameters with high reproducibility and repeatability in the kidneys of healthy dogs. A combination of b = 0, 100, and 800 s/mm2 can be used for ADC measurements when multiple b-values are not available in dogs.

CT-based classification systems for intra-articular calcaneal fractures: the inter- and intra-observer variations as well as integrality

Background: Several primary fracture classification systems (FCSs) have been widely used for intra-articular calcaneal fractures. The purpose of this study was to measure the inter- and intra-observer variations as well as integrality of the Zwipp, Crosby-Fitzgibbons, Sanders, and Eastwood-Atkins classification systems based on more accurate CT scans. Methods: 549 patients with intra-articular calcaneal fractures taken from a database in our level-I trauma centre (3 affiliated hospitals) were included from January 2018 to December 2019. For each case, normative CT (1 mm slices) scans were available. Four different observers reviewed all CT scans two times according to these 4 most prevalent FCSs within a 2-month interval. For these four FCSs, the kappa [κ] coefficient was used to evaluate interobserver reliability and intraobserver reproducibility, and the percentage that can be classified was used to indicate integrality. Results: The κ values were measured for Zwipp (κ= 0.38 interobserver, κ= 0.61 intraobserver), Crosby-Fitzgibbons (κ= 0.48 interobserver, κ= 0.79 intraobserver), Sanders (κ= 0.40 interobserver, κ= 0.57 intraobserver), and Eastwood-Atkins (κ= 0.44 interobserver, κ= 0.72 intraobserver). Furthermore, the integrality were calculated for Zwipp (100 %), Crosby-Fitzgibbons (100 %), Sanders (92 %) as well as Eastwood-Atkins (89.6 %). Conclusion: Compared with previous literatures, CT scanning with higher accuracy can significantly improve intraobserver reproducibility of Zwipp and Eastwood-Atkins FCSs, but it has no positive effect on variability of Sanders FCS and interobserver reliability of Crosby-Fitzgibbons FCS. While in terms of integrality, Zwipp and Crosby-Fitzgibbons FCSs appear to be superior to the other two FCSs.

Intra and Inter-observer Concordance of a New Classification System for Myopic Maculopathy

Background: Myopic maculopathy (MM) is one of the major causes of visual impairment and irreversible blindness in eyes with PM. However, the classification of each type of lesion associated with MM has not been determined. Recently, a new MM classification system was proposed, known as the ATN grading and classification system, which was based on the fundus photographs and OCT images, including three variable components: atrophy (A), traction (T), and neovascularization (N). Hence, this study aimed to perform an independent interobserver and intraobserver agreement evaluation of the recently developed ATN grading system for MM. Methods: This was a retrospective study. Fundus photographs and the optical coherence tomography (OCT) images of 125 patients (226 eyes) with various of MM were evaluated and classified using the ATN grading of the new MM classification system by four evaluators (2 attending ophthalmologists and 2 ophthalmic residents). All cases were repeatedly evaluated by the same evaluators after an interval of 6 weeks. The Kappa coefficient (κ) and 95% confidence interval (CI) were used to determine the interobserver and intraobserver agreement.Results: The interobserver reliability was substantial when considering the maculopathy type (A, T, and N). The weighted Fleiss κ values for each MM type (A, T, and N) were 0.651 (95% CI: 0.602–0.700), 0.734 (95% CI: 0.689–0.779), and 0.702 (95% CI: 0.649–0.755), respectively. The interobserver agreement when considering the sub-types was good or excellent, except for stages A1, A2, and N1 which weighted κ value was less than 0.6, with a moderate agreement. The intraobserver reproducibility of types or sub-types was excellent, with κ>0.8. No significant differences were observed between attending ophthalmologists and residents in the interobserver reliability and intraobserver reproducibility.Conclusions: The ATN classification allows an adequate agreement among ophthalmologists with different qualifications and by the same observer on separate occasions. Future prospective studies should further evaluate whether this classification can be better implemented at clinical decision-making and disease progression assessment.

Craniometric parameters for the evaluation of platybasia and basilar invagination on magnetic resonance imaging: a reproducibility study

Objective: The present study aims to perform a reproducibility study of the clivus-canal angle (CCA), Welcker’s basal angle (WBA), and the distance from the odontoid process to Chamberlain’s line (DOCL) on magnetic resonance imaging (MRI). Materials and Methods: Two medical students and two radiologists respectively evaluated 100 and 50 consecutive MRI scans of adult skulls, selected randomly. Each examiner, working independently and blinded to the previous results, performed readings for each patient on two different occasions. Measurements were performed in T1-weighted sequences acquired in the midsagittal plane. The levels of intraobserver reproducibility and interobserver agreement were evaluated by calculating the intraclass correlation coefficients (ICCs) and the corresponding 95% confidence intervals. Results: The mean values obtained by the examiners were 150° for the CCA, 130° for the WBA, and 2.5 mm for the DOCL. The ICC for interobserver agreement was 0.980, 0.935, and 0.967, for the CCA, WBA, and DOCL, respectively, for the students, compared with 0.977, 0.941, and 0.982, respectively, for the radiologists, and 0.980, 0.992, and 0.990, respectively, for all of the examiners together. In the analysis of intraobserver agreement, the ICC ranged from 0.929 to 0.959 for the CCA, from 0.918 to 0.964 for the WBA, and from 0.918 to 0.981 for the DOCL. Conclusion: The measurement of the CCA, WBA, and DOCL appears to show excellent intraobserver reproducibility and interobserver agreement on MRI.

Reproducibility of macular retinal nerve fiber layer and ganglion cell layer thickness measurements in a healthy pediatric population

Purpose: To evaluate the reproducibility of Spectralis spectral domain-OCT segmented ganglion cell layer (GCL) and macular retinal nerve fiber layer (mRNFL) measurements in a healthy children population. Methods: An observational, cross-sectional study was carried out on 79 children to measure the intraobserver reproducibility and the repeatability between a novel and an experienced operator of the segmented macular GCL and mRNFL. Interobserver and intraobserver reproducibility were defined by the intraclass correlation coefficient (ICC) and coefficients of variation (COV). Kruskal–Wallis test was used to determine statistical significance in the COV of three age groups children (younger than 6 years, between 6 and 12, and older than 12 years old). Results: The results from the intraoperator GCL thickness analysis were highly reproducible (COV < 6%) and reliable (ICCs > 0.81). When the measurements were compared between a novel and an experienced examiner lower ICCs and higher COV were found. COVs ranged from 1.85% (total volume area) to 5.57% at the central ETDRS subfield while the ICC vary from 0.632 (outer inferior) to 0.832 (inner inferior). The repeatability and reproducibility of the mRNFL thickness were lower, with ICCs ranging from 0.428 to 0.872 in the interobserver analysis and from 0.897 to 0.346 in the interobserver one. Conclusion: In the present study, we establish substantial reliability of the GCL thickness in children with Spectralis® SD-OCT in all the sectors, albeit lower than the reported in the literature with other SD-OCTs and in adults. The reproducibility and repeatability of the mRNFL were significantly lower. We were unable to find consistent statistical significant differences between the COV of the three age groups.