Interobserver Kappa Research Articles

Small (≤2 cm) atypical hepatic haemangiomas in the non-cirrhotic patient: pattern-based classification scheme for enhancement at triple-phase helical CT

The aim of this study was to determine by triplephase helical computed tomography (CT) the appearance of atypical small (< or = 2 cm) hepatic haemangiomas (HHs) in the non-cirrhotic patient. We retrospectively reviewed the hepatic arterial-dominant phase (HAP), portal venous phase (PVP) and delayed-phase (DP) helical CT images of 47 patients with 52 atypical small (< or = 2 cm) HHs associated with 34 typical small HHs. Images were assessed to identify the patterns of enhancement of atypical HHs and correlate their appearance with that of typical small HHs in the delayed phase. Interobserver variability and kappa value were calculated. Statistical significance was calculated by the Fisher exact test. The 52 atypical small HHs were categorised as follows: type 1a (hyperattenuating in the HAP, n=17), type 1b [hyperattenuating with transient hepatic attenuation difference (THAD) around the lesion in the HAP, n=12], type 2a (homogeneously hypoattenuating in the HAP or PVP, n=9), type 2b (hypoattenuating with "bright-dot" sign in the HAP or PVP, n=13) and type 3 (hypoattenuating with central enhancing area, n=1). Interobserver agreement was perfect for HHs of types 1a, 1b, 2a and 3. On DP images, the appearance of atypical small HHs was identical to that of typical small HHs in all cases (p<0.0001), with lesions showing homogeneous isoattenuation to the aorta or liver parenchyma without peripheral capsule. Triple-phase helical CT scans can distinguish several types of atypical small HHs. The demonstration of patterns similar to those of typical forms on DP CT is fundamental for the diagnosis.

Histologic grading of invasive lobular carcinoma: does use of a 2-tiered nuclear grading system improve interobserver variability?

The Nottingham histologic grade (NHG) is a prognostic marker for infiltrating ductal carcinoma. Its usefulness for invasive lobular carcinoma (ILC) has been less clear, given that 2 of the 3 parameters, tubule formation and mitotic activity, show little variation in ILC, placing much of the emphasis on nuclear grade. We have previously reported a trend for improved overall and relapse-free survival in patients with ILC of low nuclear grade, as classified by a 2-tiered nuclear grading system. Given the inherent potential for interobserver variability with any grading system, the goal of this study is to compare interobserver variability in the grading of ILC using a 2-tiered nuclear grade vs the NHG. Thirty-eight cases of ILC were graded independently by 5 pathologists using NHG criteria. Tumors were also categorized by a nuclear grading system as low grade (grade 1 nuclei) or high grade (grades 2-3 nuclei). Pairwise kappa values and interobserver agreement rates were calculated for both NHG and nuclear grade. Results were compared using the paired t test. Mean interobserver agreement rates and kappa values improved with use of the nuclear grading system as compared to NHG (83% vs 70%, 0.4738 vs 0.3228, respectively). The differences between the 2 were statistically significant. Because histologic grade has significant prognostic implications for patients with breast cancer, accurate reporting is paramount. For ILC, where use of the NHG places substantial weight on nuclear pleomorphism, a 2-tiered nuclear grading system may reduce interobserver variability yet still provide useful prognostic information.

The Measurement of the QT and QTc on the Neonatal and Infant Electrocardiogram: A Comprehensive Reliability Assessment

An electrocardiogram has been proposed to screen for prolonged QT interval that may predispose infants to sudden death in the first year of life. Understanding the reliability of QT interval measurement will inform the design of a screening program. Three pediatric cardiologists measured the QT/RR intervals on 60 infant electrocardiograms (median age 46 days), from leads II, V5 and V6 on three separate occasions, 7 days apart, according to a standard protocol. The QTc was corrected by Bazett's (QTcB), Fridericia's (QT(CFrid)), and Hodges' (QTcH) formulae. Intraobserver and interobserver reliability were assessed by intraclass correlation coefficients (ICC), limits of agreement and repeatability coefficients for single, average of two and average of three measures. Agreement for QTc prolongation (> 440 msec) was assessed by kappa coefficients. QT interval intraobserver ICC was 0.86 and repeatability coefficient was 25.9 msec; interobserver ICC increased from 0.88 for single observations to 0.94 for the average of 3 measurements and repeatability coefficients decreased from 22.5 to 16.7 msec. For QTcB, intraobserver ICC was 0.67, and repeatability was 39.6 msec. Best interobserver reliability for QTcB was for the average of three measurements (ICC 0.83, reproducibility coefficient 25.8 msec), with further improvement for QTcH (ICC 0.92, reproducibility coefficient 16.69 msec). Maximum interobserver kappa for prolonged QTc was 0.77. Misclassification around specific cut points occurs because of the repeatability coefficients. Uncorrected QT measures are more reliable than QTcB and QT(CFrid). An average of three independent measures provides the most reliable QT and QTc measurements, with QTcH better than QTcB.

Association of lumbar arterial stenosis with low back symptoms: A cross-sectional study using two-dimensional time-of-flight magnetic resonance angiography

Recent studies indicate that diminished blood flow may cause low back symptoms and intervertebral disc degeneration. To explore the association between lumbar arterial stenosis as detected by two-dimensional time-of-flight magnetic resonance angiography (2D TOF-MRA) and lumbar pain symptoms in an occupational cohort of middle-aged Finnish males. 228 male subjects aged 36 to 55 years (mean 47 years) were imaged with 2D TOF-MRA. Additionally, 20 randomly selected subjects were scanned with contrast-enhanced MRA (ceMRA). In each subject, the first (L1) to fourth (L4) segmental lumbar arteries were evaluated for lumbar artery stenosis using a dichotomic scale. One subject was excluded because of poor image quality, reducing the study population to 227 subjects. Logistic regression analysis was used to evaluate the association between arterial stenosis in 2D TOF-MRA and low back pain and sciatica symptoms (intensity, duration, frequency). Comparing 2D TOF-MRA and ceMRA images, the kappa value (95% confidence interval) was 0.52 (0.31-0.73). The intraobserver reliability kappa value for 2D TOF-MRA was 0.85 (0.77-0.92), and interobserver kappa was 0.57 (0.49-0.65). The sensitivity of 2D TOF-MRA in detecting stenosis was 0.58, the accuracy 0.89, and the specificity 0.94. In 97 (43%) subjects all arteries were normal, whereas 130 (57%) had at least one stenosed artery. The left L4 artery was most often affected. The degree of arterial stenosis was associated with intensity of low back and sciatic pain, and sciatica pain duration during the past 3 months. 2D TOF-MRA is an acceptable imaging method for arterial stenosis compared to ceMRA. Arterial stenosis was associated with subjective pain symptoms, indicating a role of decreased nutrition in spinal disorders.

Scientific Sessions

Purpose: To compare entero-MDCT with entero-MRI performed for suspicion of acute exacerbation of known Crohn's disease. Methods and Materials: Fifty-seven patients (mean age 33.5) with histologically proven Crohn's disease were prospectively included. They presented with clinical symptoms suggesting acute exacerbation to the emergency department. After oral administration of 1-2 l of 5% methylcellulosis (+syrup), entero-MDCT and entero- MRI were performed on each patient (mean delay 1 day). Three experienced radiologists blindly and independently evaluated each examination for technical quality, eight pathological CT features (bowel wall thickening, pathological wall enhancement, stenosis, lymphadenopathy, mesenteric haziness, intraperitoneal fluid, abscess, fistula) and final main diagnosis. Interobserver agreement kappa was calculated. Sensitivity and specificity resulted from comparison with the reference standard, consisting of operation (n= 30) and long-time follow-up in case of conservative treatment (n=27). Results: Entero-MDCT demonstrated considerably less artefacts than entero-MRI (p 0.0001). In 9 entero-MDCT/-MRI, no activity of Crohn's disease was seen, whereas in 48 entero-MDCT/-MRI active disease could be demonstrated, such as intraperitoneal abscesses (n=11), fistulas (n=13), stenoses (n=23), acute (n=15) or chronic (n=23) inflammation. Interobserver agreement of the three readers was not significantly different between entero-MDCT and -MRI, neither was sensitivity (range 60-89%) and specificity (range 75-100%) for each of the eight pathological features or for the main diagnosis. Conclusion: Entero-MRI is statistically of similar diagnostic value as entero-MDCT for acute complications of Crohn's disease. Therefore, entero-IRM, devoid of harmful irradiation, should become the preferred imaging modality, since we deal with young patients, very likely exposed to frequent imaging controls in the future.

Image Subtraction Facilitates Assessment of Volume and Density Change in Ground-Glass Opacities in Chest CT

To study the impact of image subtraction of registered images on the detection of change in pulmonary ground-glass nodules identified on chest CT. A cohort of 33 individuals (25 men, 8 women; age range 51-75 years) with 37 focal ground-glass opacities (GGO) were recruited from a lung cancer screening trial. For every participant, 1 to 3 follow-up scans were available (total number of pairs, 84). Pairs of scans of the same nodule were registered nonrigidly and then subtracted to enhance differences in size and density. Four observers rated size and density change of the GGO between pairs of scans by visual comparison alone and with additional availability of a subtraction image and indicated their confidence. An independent experienced chest radiologist served as an arbiter having all reader data, clinical data, and follow-up examinations available. Nodule pairs for which the arbiter could not establish definite progression, regression, or stability were excluded from further evaluation. This left 59 and 58 pairs for evaluation of size and density change, respectively. Weighted kappa statistics (kappa w) were used to assess interobserver agreement and agreement with the arbiter. Statistical significance was tested with a kappa z-test. When the subtraction image was available, the average interobserver kappa w improved from 0.52 to 0.66 for size change and from 0.47 to 0.57 for density change. Average agreement with the arbiter improved from 0.61 to 0.76 for size change and from 0.53 to 0.64 for density change. The effect was more pronounced when observer confidence without the subtraction image was low: agreement improved from 0.26 to 0.57 and from 0.19 to 0.47 in those cases. Image subtraction improves the evaluation of subtle changes in pulmonary ground-glass opacities and decreases interobserver variability.

Reproducibility determination of WHO classification of endometrial hyperplasia/well differentiated adenocarcinoma and comparison with computerized morphometric data in curettage specimens in Iran

BackgroundManagement of endometrial precancerous lesions has been of much debate due to inconsistencies in their classification, natural history and histologic diagnosis. Endometrial hyperplasia constitutes a wide range of histomorphologic features associated with high intra and interobserver diagnostic variability.Although traditional microscopic diagnosis is by far the most applicable method and the gold standard for histomorphologic diagnosis, digitized image analysis has been used as a powerful adjunct to maximize the histologic data retrieval and to add some detailed objective criteria for correct diagnosis in difficult cases.MethodsA series of 100 endometrial curettage specimens with diagnosis of endometrial hyperplasia or well differentiated adenocarcinoma were blindly reviewed by 5 pathologists; their intra and interobserver reproducibility determined and further compared to the objective morphometric data i.e. D-score and volume percent of stroma (VPS).ResultsThe results were assessed using the weighted kappa statistics. Mean intraobserver kappa value was 0.8690 (99.44% agreement). Mean interobserver kappa values by diagnostic category were: simple hyperplasia without atypia: 0.7441; complex hyperplasia without atypia: 0.3379; atypical hyperplasia: 0.3473, and well-differentiated endometrioid carcinoma: 0.6428; with a kappa value of 0.5372 for all cases combined.Interobserver agreement was in substantial rate for simple hyperplasia (SH) and well differentiated adenocarcinoma (WDA) but was in fair limit for complex hyperplasia (CH) and atypical hyperplasia (AH). Intraobserver agreement was almost perfect. The specimens were divided in two groups according to the computerized morphometric analysis: Endometrial Hyperplasia (EH) ( D Score ≥ 1 or VPS ≥ 55%) and Endometrial Intraepithelial Neoplasia (EIN) (D-Score < 1 or VPS < 55%). Morphometric findings were closely compatible with routine WHO classification made by one expert pathologist; however; diagnosis of (CH) and (AH) made by other pathologists were not concordant with morphometric data.ConclusionIt may be necessary to make some revisions in WHO classification for endometrial hyperplasia and precancerous lesions.

How to evaluate and improve the reliability of power Doppler ultrasonography for assessing enthesitis in spondylarthritis

To evaluate and improve the reliability of power Doppler ultrasonography (PDUS) for detecting and scoring enthesitis in patients with spondylarthitis, using a 3-step procedure. In the first step, we evaluated the reliability of 5 sonographers by bilaterally scanning 5 entheses twice in 5 patients. In the second step, starting from disagreements observed during the first step, we established consensus guidelines. The sonographers' implementation was further evaluated in 2 reliability exercises: one on 60 PDUS enthesitis images and the other by scanning 5 new patients. In the third step, we performed a final reliability evaluation of 5 additional patients after 1 year. Kappa coefficients (kappa) as well as variance component analysis (VCA) and generalizability theory (GT) were used to assess reliability. The initial intra- and interobserver reliability were poor, especially for detecting and scoring Doppler signal. VCA and GT showed that most variability was accounted for by interaction between sonographer and enthesis. Implementation of consensus guidelines was associated with a significant improvement in Doppler reliability between the first and second steps (mean interobserver kappa increased from 0.13 to 0.51 for binary Doppler scoring in patients; P < 0.005), which persisted in the third step (mean interobserver kappa = 0.57). The high GT coefficients reached in the last steps supported such improvement. The 3-step procedure used in this study to standardize PDUS technique was associated with a significant improvement in interobserver reliability for detecting enthesitis in spondylarthritis patients. Such an approach can be useful to standardize PDUS assessment of musculoskeletal disorders.

Optic Disc Progression in Glaucoma: Comparison of Confocal Scanning Laser Tomography to Optic Disc Photographs in a Prospective Study

To compare confocal scanning laser tomography (CSLT) to optic disc photography for detecting progressive glaucomatous disc changes. Four expert observers first examined a training set of 40 pairs of monoscopic disc photographs to help set a criterion for change. They then classified 44 pairs of monoscopic photographs of patients followed prospectively as having either definitely no change, probably no change, probably change, or definitely change (score, 0, 1, 2, or 3, respectively). Observers were unaware that 10 pairs were photographs of fellow eyes obtained the same day to measure specificity. These patients were imaged with the Heidelberg Retina Tomograph every 6 months. Topographic change analysis (TCA) software with three criteria (yielding specificity of 81%, 94%, or 97%) was used. Comparisons between the TCA results and those of observers were made for a range of liberal to conservative criteria and for individual and combined observer scores. The median follow-up was 9.0 years with 18 CSLT images. Observer specificity varied from 50% to 90% (using score 0) and 60% to 100% (using score 0 or 1). Interobserver kappa ranged from 0.22 to 0.38 from the most liberal to conservative criterion and was generally higher than corresponding TCA-observer agreement. For most criteria, observers had either a high hit rate with low specificity or high specificity with a low hit rate compared with the TCA. Similar results were obtained when observer scores were combined to derive a broader range of criteria. The results indicate that the TCA performs at least as well as either the individual or best combination of observer classifications of disc photographs.

Confiabilidad y reproducibilidad de la escala de fototipos de Fitzpatrick antes y después de un ejercicio de estandarización clínica

The Fitzpatrick phototype scale has been used to determine skin sensitivity to ultraviolet light. The reliability of this scale in estimating sensitivity permits risk evaluation of skin cancer based on phototype. Reliability and changes in intra and inter-observer concordance was determined for the Fitzpatrick phototype scale after the assessment methods for establishing the phototype were standardized. An analytical study of intra and inter-observer concordance was performed. The Fitzpatrick phototype scale was standardized using focus group methodology. To determine intra and inter-observer agreement, the weighted kappa statistical method was applied. The standardization effect was measured using the equal kappa contrast hypothesis and Wald test for dependent measurements. The phototype scale was applied to 155 patients over 15 years of age who were assessed four times by two independent observers. The sample was drawn from patients of the Centro Dermatol6gico Federico Lleras Acosta. During the pre-standardization phase, the baseline and six-week inter-observer weighted kappa were 0.31 and 0.40, respectively. The intra-observer kappa values for observers A and B were 0.47 and 0.51, respectively. After the standardization process, the baseline and six-week inter-observer weighted kappa values were 0.77, and 0.82, respectively. Intra-observer kappa coefficients for observers A and B were 0.78 and 0.82. Statistically significant differences were found between coefficients before and after standardization (p<0.001) in all comparisons. Following a standardization exercise, the Fitzpatrick phototype scale yielded reliable, reproducible and consistent results.

Risser sign inter-rater and intra-rater agreement: is the Risser sign reliable?

Studies directly evaluating the reliability of the Risser sign are few in number, possess small sample sizes, and offer conflicting results. This study establishes the reliability of the Risser sign on a large sample size in an effort to provide clarification on the subject. Two years' worth of AP pelvis radiographs from patients age 8-20 were downloaded from our institution's digital imaging system. One hundred of these images were selected for inclusion by an independent reviewer whose goal was to capture a spread of radiographs that included all Risser stages. Risser grading occurred in two rounds. In each round, three examiners randomly reviewed the 100 radiographs on three different occasions. The full AP pelvis radiograph was graded in Round 1 while only the iliac apophysis was visible in Round 2. Kappa coefficients and their confidence bounds are reported to indicate intra- and inter-observer reliability. The contrast between the rates of agreement about Risser stages in Rounds 1 versus 2 was assessed by McNemar's test. The signed-rank test was used to evaluate differences in intra-observer values between rounds. Round 1 inter-observer kappa was 0.76. Round 2 inter-observer kappa was 0.51. In Round 1, 63 radiographs showed perfect agreement within the same Risser stage for all observations compared to 44 radiographs with perfect agreement within the same Risser stage in Round 2 (p = 0.004). Round 1 intra-observer kappa values were 0.92, 0.86, and 0.88. Round 2 intra-observer kappa values were 0.91, 0.77, and 0.88. Intra-observer value differences between rounds were not significant for two observers (p = 0.074, 0.061) but was significant for the third observer (p = 0.002). The reliability of the Risser sign is acceptable and can be further improved when other markers of skeletal maturity on the pelvis radiograph are used to assist in grading.

Postoperative chest tube management: measuring air leak using an electronic device decreases variability in the clinical practice☆☆☆

Since there are no data in the literature regarding variability in the management of postoperative pleural drainages, we have designed a prospective randomized study aimed at measuring inter-observer variability in deciding when to withdraw chest tubes after lung resection and to evaluate if the use of an electronic device to measure postoperative air leak decreases clinical practice variations. Sixty-one patients undergoing pulmonary resection were randomly assigned to one of the following groups: digital group (electronic measure of pleural air leak using Millicore AB DigiVent chest drainage system) or traditional group (standard water seal pleural chamber). Chest tube withdrawal criteria were established in advance. During morning rounds, two thoracic surgeons with comparable clinical experience and blinded to the decision of their counterpart, evaluated chest tube withdrawal criteria and noted whether the tube should be withdrawn or not. Inter-observer variability kappa index and global, positive, and negative agreement rates were calculated on 2 x 2 tables. Each observation episode was considered in the calculation. Fifty-four observations were recorded in the traditional group. Kappa coefficient was 0.37 (overall agreement rate: 0.58; positive agreement rate: 0.72; and negative agreement rate: 0.64). In the digital group, 67 observations were recorded. Kappa coefficient was 0.88 (overall agreement rate: 0.94; positive agreement rate 0.94; and negative agreement rate 0.94). We have demonstrated a high rate of disagreement related to the indication to remove chest tubes after lung resection and the improvement of the agreement rate with the use of an electronic device to measure postoperative air leak and pleural pressures.

Observer variation in FDG PET-CT for staging of non-small-cell lung carcinoma

Error and variation in reporting remains one of the weakest features of clinical imaging despite enormous technological advances in nuclear medicine and radiology. The aim of this study was to evaluate agreement amongst experienced readers in staging non-small-cell lung cancer (NSCLC) with PET-CT. A series of (18)F-FDG PET-CT scans from 100 consecutive patients were reviewed independently by three experienced readers, with two readers reviewing each scan series a second time. Individual mediastinal lymph node stations were assessed as benign/inflammatory, equivocal or malignant, and AJCC N and M stage were also assigned. Kappa (kappa) was used to compare ratings from two categories and weighted kappa (kappa(w)) for three or more categories, and kappa values were interpreted according to the Landis-Koch benchmarks. Both intra- and interobserver agreement for N and M staging were high. For M staging there was almost perfect intra- and interobserver agreement (kappa = 0.90-0.93). For N staging, agreement was either almost perfect or substantial (intraobserver kappa(w) = 0.79, 0.91; interobserver kappa(w) = 0.75-0.81). Importantly, there was almost perfect agreement for N0/1 vs N2/3 disease (kappa = 0.80-0.97). Agreement for inferior and superior mediastinal nodes (stations 1, 2, 3, 7, 8, 9) was either almost perfect or substantial (kappa(w) = 0.71-0.88), but lower for hilar nodes (10; kappa(w) = 0.56-0.71). Interreporter variability was greatest for aortopulmonary nodes (5, 6; kappa(w) = 0.48-0.55). Amongst experienced reporters in a single centre, there was a very high level of agreement for both mediastinal nodal stage and detection of distant metastases with PET-CT. This supports the use of PET-CT as a robust imaging modality for staging NSCLC.

Using a Higher Cutoff for the Percentage of HER2+ Cells Decreases Interobserver Variability in the Interpretation of HER2 Immunohistochemical Analysis

The effect of using a 30% cutoff for the proportion of HER2+ cells on the interobserver variability in the interpretation of HER2 immunohistochemical results was evaluated. Immunostained sections from 96 cases of breast carcinoma were reviewed by 10 pathologists and scored as positive (3+) when uniform strong membranous staining was identified in at least 10% of tumor cells; the actual percentage of cells with such staining was also estimated. The agreement rates and the kappa values using a 30% cutoff were compared with those using a 10% cutoff. These proved to be higher in 62% and 66% of measurements, respectively, with average interobserver rates and kappa values of 72% and 0.54 using the 30% cutoff and 70% and 0.49 using the 10% cutoff (P=.001 for all comparisons). Using a 30% cutoff for the percentage of HER2+ cells by immunohistochemical analysis modestly decreased interobserver variability in the interpretation of HER2 immunohistochemical results.

Diagnostic sensitivity of multidetector-row spiral computed tomography angiography in the evaluation of type-ii endoleaks and their source: comparison between axial scans and reformatting techniques

After endovascular stent-graft placement, several complications may occur. Retrograde filling of the aneurysm (type-II endoleak) is the most common. To evaluate the accuracy, image quality, and interobserver agreement of multidetector-row spiral computed tomography angiography (MDCTA) in the diagnosis of type-II endoleak, by using various types of reformatting techniques in comparison to regular axial images. Twenty-four patients who had had endovascular repair of an infrarenal abdominal aortic aneurysm with stent graft were retrospectively studied. In 12 of 24 patients, a type-II endoleak was found. CT scans were obtained after intravenous administration of 130 ml of nonionic contrast material using a 4-6-ml/s flow rate. All patients were investigated with axial scans, multiplanar reconstruction (MPR), maximum intensity projection (MIP), shaded-surface display (SSD), and volume-rendering (VR) techniques. For each patient and for each reconstruction method, the image quality of the scans was scored as 0 for bad quality, 1 for poor quality, 2 for good quality, and 3 for excellent quality images. Two radiologists reviewed the CT images independently. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each reconstruction method, with the axial images as the reference method. Interobserver agreement and kappa value were also recorded. MPR showed the highest sensitivity (83% and 67% for observers 1 and 2, respectively), PPV (91% and 80% for observers 1 and 2, respectively), and NPV (85% and 71% for observers 1 and 2, respectively), whereas VR showed the highest specificity (92% for both observer 1 and 2). Reformatting techniques provide good-quality images; nevertheless, their efficacy in the study of type-II endoleak was found to be suboptimal in comparison to regular axial images. The MPR technique is probably the best choice in conjunction with axial images.

Assessment of Dural Arteriovenous Fistulas of the Cavernous Sinuses on 3D Dynamic MR Angiography

Flow voids within the cavernous sinuses and/or certain venous drainage on spin-echo MR imaging and time-of-flight (TOF) flow enhancement on MR angiography (MRA) have indicated high-velocity shunt flow and have been used for screening patients with dural arteriovenous fistulas (DAVFs) of the cavernous sinuses. In this investigation, the capabilities of 3D dynamic MRA as a flow-independent approach and those of conventional MR imaging techniques were compared with selective angiography for the diagnosis of DAVFs of the cavernous sinuses. This retrospective study involved 18 patients with angiographically proved DAVFs of the cavernous sinuses and 12 control subjects. Sixteen partially overlapping sequential MR images were acquired on contrast-enhanced 3D dynamic MRA between the petrosal bone and the orbital roof. Two experienced observers blinded to the clinical data and results of angiography independently graded 3D dynamic MRA, fast spin-echo T2-weighted imaging (FSE T2WI), and TOF MRA. The average area under the receiver operating characteristic curve values and interobserver kappa scores for the diagnosis of DAVFs on 3D dynamic MRA, FSE T2WI, and TOF MRA were 0.99, 0.89, and 0.95; and 0.92, 0.71, and 0.73, respectively. Those for the diagnosis of anterior, posterior, and retrograde cortical venous drainage on 3D dynamic MRA were 0.72, 0.95, and 0.81; and 0.56, 0.50, and 0.49, respectively. In this small series, screening 3D dynamic MRA directly demonstrates DAVFs of the cavernous sinuses and has improved diagnostic capability.

Comparative analysis of Pediatric Uroflowmetry

OBJECTIVE In literature, comparative analysis of Uroflowmetry has only been done for prostate obstruction. Inter- and intra-observer agreement for pediatric Uroflowmetry has never been tested systematically. MATERIAL AND METHODS Eight professionals in pediatric incontinence care judged 480 pediatric uroflows in a web-based computer system that had been designed for professional use in the sewer industry. Uroflows were assessed on 4 items: staccato, interrupted, flow-time, and obstruction in a 1-5 scale. For intra-observer agreement 100 flows were judged a second time one month later. Statistical analysis was done to determine Kappa values for agreement. Kappa 0.4- 0.6 was considered moderate agreement, 0.6- 0.8 substantial agreement and >0.8 almost perfect agreement. RESULTS In the inter-observer agreement Kappa was 0.45 for staccato, 0.67 for interrupted, 0.59 for flow-time and 0.66 for obstruction. For intra-observer agreement the overall mean Kappa was 0.47 for staccato, 0.65 for interrupted, 0.55 for flow-time and 0.65 for obstruction. CONCLUSIONS Standardized analysis of pediatric Uroflowmetry in a structured way learns that moderate to substantial agreement exists between professionals. This agreement is very comparable with the intra-observer agreement for each of the professionals. Uroflowmetry is both for diagnosis of LUTS in children and for follow-up during urotherapy a reliable and reproducible, non-invasive tool.

Improved detection of recurrent laryngeal tumor after radiotherapy using 18FDG-PET as initial method

Background and purpose Timely detection of recurrent laryngeal tumor after radiation is an important predictive factor for curation as well as preservation of laryngeal function. Direct laryngoscopy under general anesthesia with taking of biopsies is the standard diagnostic procedure to detect recurrence when suspicion is raised. This, however, is an invasive and potentially damaging technique. Hence, a non-invasive diagnostic procedure, such as 18FDG-PET to stratify patients for direct laryngoscopy could be useful. 18FDG-PET is interpreted visually so that observer variation may affect clinical practice. In the present study, we therefore investigated this aspect of reproducibility. Patients and methods Thirty consecutive patients suspected of recurrent laryngeal carcinoma after radiotherapy underwent 18FDG-PET and direct laryngoscopy under general anesthesia with taking of biopsies. 18FDG-PET scans were reported by nine nuclear medicine physicians and residents, using a three-point scaling system. The reference was the absence or appearance of a local recurrence in the 12 months following 18FDG-PET. Results Eight patients had biopsy proven recurrent laryngeal carcinoma. Sensitivity of 18FDG-PET was 88% (95% CI 53–98%) and specificity was 82% (95% CI 62–93%). The observers had a moderate to reasonable agreement (weighted kappa 0.45 (95% CI 0.20–0.69)) vs. the clinical gold standard and interobserver kappa was 0.54 (95% CI 0.40–0.69). Conclusion 18FDG-PET seems to be a promising technique to detect recurrent laryngeal carcinoma after radiotherapy, and selecting patients for direct laryngoscopy. This will avoid futile invasive procedures. Interobserver agreement and variability is reasonable using this technique, but training is necessary. Studies comparing different strategies to select patients for direct laryngoscopy in case of suspected recurrence are warranted.

Does Vertebral Endplate Morphology Influence Outcomes in Lumbar Disc Arthroplasty? Part I: An Initial Assessment of a Novel Classification System of Lumbar Endplate Morphology

Background The influence of lumbar endplate morphology on the clinical and radiographic outcomes of lumbar disc arthroplasty has not been evaluated to the best of our knowledge. Study Design and Objective In this observational study of 80 patients, the objective was to formulate a reproducible and valid lumbar endplate classification system to be used in evaluating lumbar total disc replacement patients. Methods A novel vertebral endplate morphology classification system was formulated after review of data related to 80 patients enrolled in a prospective, randomized clinical trial in conjunction with an application for a US Food and Drug Administration investigational device exemption. Intraobserver and interobserver analyses of the classification system were performed on the same 80 patients utilizing the classification system. Results The initial review of the radiographs revealed 5 types of endplates: Type I (n = 82) flat endplates; Type II (n = 26) posterior lip; Type III (n = 5) central concavity; Type IV (n = 4) anterior sloping endplate; and Type V (n = 2) combination of Types I–IV. The intraobserver kappa was 0.66 and the interobserver kappa was 0.51. These kappa values indicate “substantial” to “moderate” reproducibility, respectively. Conclusions In this study, we propose a lumbar endplate classification system to be used in the preoperative assessment of patients undergoing lumbar disc arthroplasty. The classification can function as a basis for comparison and discussion among arthroplasty clinicians, and serve as a possible exclusionary screening tool for disc arthroplasty. Special consideration should be given to Type II endplates to optimize proper positioning and functioning of a total disc replacement (TDR) implant. Further outcome studies are warranted to assess the clinical significance of this classification system. The key points of our study are: (1) We present a novel lumbar vertebral endplate classification system; (2) Five types of endplates were identified and classified; (3) Intraobserver and interobserver reliability were classified as substantial and moderate, respectively; and (4) The classification system used may assist in the preoperative evaluation of patients for total disc replacement. Level of Evidence A systematic review of cohort studies (level 2a).

Reliability and accuracy of fine-cut computed tomography scans to determine the status of anterior interbody fusions with metallic cages

Background context Computed tomography (CT) scan has been shown to be more accurate than radiographs in evaluating anterior interbody fusion but may still over-read the extent of fusion. Purpose To assess the reliability and accuracy of fine-cut CT scans with reconstructions in evaluating anterior lumbar interbody fusion (ALIF) with metallic cages using surgical exploration as the reference standard. Study design Accuracy of a diagnostic test referenced to the gold standard. Patient sample A total of 49 patients and 69 surgical levels. Outcome measures Evaluation of fine-cut CT scans for evidence of fusion with subsequent surgical exploration as the reference standard. Methods Forty-nine patients who underwent ALIF with metallic cages over 69 levels, who had a fine-cut CT scan before revision were included. Five spine surgeons unaware of the findings on surgical exploration evaluated pre-revision CT scans, classified these as fused or not; and determined the presence of a “sentinel sign” and a “posterior sentinel sign.” Kappa coefficients for interobserver reliability, sensitivity, and specificity to detect fusion were determined. Results There were 26 males and 23 females with a mean age of 43 years. There were 27 smokers. Average time from index to revision surgery was 22 months. Interobserver kappa for classification as fused or not was 0.25 with 70% to 97% sensitivity and 28% to 85% specificity. The interobserver kappa for the sentinel sign was 0.34 with 13% to 33% sensitivity and 77% to 92% specificity. The interobserver kappa for the posterior sentinel sign was 0.23 with 33% to 87% sensitivity and 56% to 90% specificity. Conclusions Raters generally overstated fusion with low specificities across raters and low consensus specificity. Overall accuracy of the posterior sentinel sign (74%) was higher than the sentinel sign (61%). The low kappa value indicates fair reliability. In patients with metallic interbody devices, surgeons should be cautious about interpreting the findings on fine-cut CT scans whether using a general assessment of the fusion, the sentinel sign, or the posterior sentinel sign.