Summary Background Public objection to autopsy has led to a search for minimally invasive alternatives. Imaging has potential, but its accuracy is unknown. We aimed to identify the accuracy of ...post-mortem CT and MRI compared with full autopsy in a large series of adult deaths. Methods This study was undertaken at two UK centres in Manchester and Oxford between April, 2006, and November, 2008. We used whole-body CT and MRI followed by full autopsy to investigate a series of adult deaths that were reported to the coroner. CT and MRI scans were reported independently, each by two radiologists who were masked to the autopsy findings. All four radiologists then produced a consensus report based on both techniques, recorded their confidence in cause of death, and identified whether autopsy was needed. Findings We assessed 182 unselected cases. The major discrepancy rate between cause of death identified by radiology and autopsy was 32% (95% CI 26–40) for CT, 43% (36–50) for MRI, and 30% (24–37) for the consensus radiology report; 10% (3–17) lower for CT than for MRI. Radiologists indicated that autopsy was not needed in 62 (34%; 95% CI 28–41) of 182 cases for CT reports, 76 (42%; 35–49) of 182 cases for MRI reports, and 88 (48%; 41–56) of 182 cases for consensus reports. Of these cases, the major discrepancy rate compared with autopsy was 16% (95% CI 9–27), 21% (13–32), and 16% (10–25), respectively, which is significantly lower (p<0·0001) than for cases with no definite cause of death. The most common imaging errors in identification of cause of death were ischaemic heart disease (n=27), pulmonary embolism (11), pneumonia (13), and intra-abdominal lesions (16). Interpretation We found that, compared with traditional autopsy, CT was a more accurate imaging technique than MRI for providing a cause of death. The error rate when radiologists provided a confident cause of death was similar to that for clinical death certificates, and could therefore be acceptable for medicolegal purposes. However, common causes of sudden death are frequently missed on CT and MRI, and, unless these weaknesses are addressed, systematic errors in mortality statistics would result if imaging were to replace conventional autopsy. Funding Policy Research Programme, Department of Health, UK.
The autopsy is in decline, despite the fact that accurate mortality statistics remain essential for public health and health service planning. The falling autopsy rate combined with the Coroners ...Review and Human Tissue Act have contributed to this decline, and to a falling use of autopsy histology, with potential impact on clinical audit and mortality statistics. At a time when the need for reform and improvement in the death certification process is so prominent, we felt it important to assess the value of the autopsy and autopsy histology. We carried out a meta‐analysis of discrepancies between clinical and autopsy diagnoses and the contribution of autopsy histology. There has been little improvement in the overall rate of discrepancies between the 1960s and the present. At least a third of death certificates are likely to be incorrect and 50% of autopsies produce findings unsuspected before death. In addition, the cases which give rise to discrepancies cannot be identified prior to autopsy. Over 20% of clinically unexpected autopsy findings, including 5% of major findings, can be correctly diagnosed only by histological examination. Although the autopsy and particularly autopsy histology are being undermined, they are still the most accurate method of determining the cause of death and auditing accuracy of clinical diagnosis, diagnostic tests and death certification.
Context. The current generation of ground-based Cherenkov telescopes, together with the LAT instrument on-board the Fermi satellite, have greatly increased our knowledge of γ-ray blazars. Among them, ...the high-frequency-peaked BL Lacertae object (HBL) PKS 1424+240 (z ≃ 0.6) is the farthest persistent emitter of very-high-energy (VHE; E ≥ 100 GeV) γ-ray photons. Current emission models can satisfactorily reproduce typical blazar emission assuming that the dominant emission process is synchrotron-self-Compton (SSC) in HBLs; and external-inverse-Compton (EIC) in low-frequency-peaked BL Lacertae objects and flat-spectrum-radio-quasars. Alternatively, hadronic models are also able to correctly reproduce the γ-ray emission from blazars, although they are in general disfavored for bright quasars and rapid flares. Aims. The blazar PKS 1424+240 is a rare example of a luminous HBL, and we aim to determine which is the emission process most likely responsible for its γ-ray emission. This will impact more generally our comprehension of blazar emission models, and how they are related to the luminosity of the source and the peak frequency of the spectral energy distribution. Methods. We have investigated different blazar emission models applied to the spectral energy distribution of PKS 1424+240. Among leptonic models, we study a one-zone SSC model (including a systematic study of the parameter space), a two-zone SSC model, and an EIC model. We then investigated a blazar hadronic model, and finally a scenario in which the γ-ray emission is associated with cascades in the line-of-sight produced by cosmic rays from the source. Results. After a systematic study of the parameter space of the one-zone SSC model, we conclude that this scenario is not compatible with γ-ray observations of PKS 1424+240. A two-zone SSC scenario can alleviate this issue, as well as an EIC solution. For the latter, the external photon field is assumed to be the infra-red radiation from the dusty torus, otherwise the VHE γ-ray emission would have been significantly absorbed. Alternatively, hadronic models can satisfactorily reproduce the γ-ray emission from PKS 1424+240, both as in-source emission and as cascade emission.
The quality technician is a person responsible for understanding and utilizing quality concepts and tools, statistical techniques, metrology and calibration procedures and protocols, inspection and ...test techniques, quality auditing, and preventive and corrective action in the context of product/process/service improvement or in correcting problems. Quality technicians frequently work in the quality function of organizations in the various measurement and inspection laboratories, as well as on the shop floor supporting and interacting with quality engineers, mechanical inspectors, and production/service delivery personnel. This book supports individuals preparing for, or those already performing, this type of work. It is intended to serve as a ready reference for quality technicians and quality technicians-in-training, as well as a comprehensive reference for those individuals preparing to take the ASQ Certified Quality Technician (CQT) examination. Examples and problems used throughout the handbook are thoroughly explained, are algebra-based, and are drawn from "real world" situations encountered in the quality profession.
The eight discipline (8D) problem-solving methodology includes the following: Select an appropriate team Formulate the problem definition Activate interim containment Find root cause(s) Select and ...verify correction(s) Implement and validate corrective action(s) Take preventive steps Congratulate the teamThis unique book provides an overview of the 8D process, gives guidance on tools for finding root causes, shows 8D in action in eight case studies, and gives five unsolved problems for readers to apply 8D themselves for practice. Anyone who wants to improve quality, regardless of the industry they come from, will benefit from the 8D approach. It has been successfully applied in healthcare, retail, finance, government, and manufacturing.
Objectives
Pulmonary embolism is believed to be a common cause of death of hospital inpatients. The aims of this study were to estimate the number of deaths caused by pulmonary embolism and the ...potential to reduce this by the use of caval filters according to accepted indications.
Design
Review of autopsy reports and death notification records from 2007 and 2008. When pulmonary embolism was given as cause of death (in the autopsy report or in section 1 a-c or part 2 of the Medical Certificate of the Cause of Death), hospital records were reviewed for evidence of pre-mortem diagnosis of pulmonary embolism or deep vein thrombosis (DVT) and for evidence of accepted indications for caval filter placement.
Setting
Large UK teaching hospital.
Participants
Hospital inpatients whose deaths were attributed to pulmonary embolism.
Main outcome measures
Proportion of deaths adjudged at autopsy to be due to pulmonary embolism; evidence of pre-mortem diagnosis of DVT or pulmonary embolism; total number of hospital admission and deaths.
Results
From a total of 186,517 adult inpatient admissions there were 2583 (1.4%) adult inpatient deaths of which 696 (27%) underwent autopsy. Of those undergoing autopsy, 14 (2.0%, 95% CI 1.2–3.3%) deaths were caused by pulmonary embolism. Pulmonary embolism was recorded as a cause of death in a further 12 (0.7%) of 1773 patients who did not undergo autopsy. Of these, five had a pre-mortem diagnosis of DVT or pulmonary embolism.
Conclusions
The proportion of deaths caused by pulmonary embolism appears to be considerably lower than the widely published rate, and of this small number, few have a pre-mortem diagnosis of DVT or pulmonary embolism. There is little scope for further reduction of pulmonary embolism mortality through use of caval filters according to guidelines. Current policy on pulmonary embolism risk prevention appears to be based on an over-estimate of the level of risk.
ObjectiveCoeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies ...using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis.DesignWe undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data.ResultsWe found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen’s kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen’s kappa coefficient of 0.67 (±0.09).ConclusionWe showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence.
Aims
The frequency of histopathological sampling at autopsy varies, even though inadequate sampling may limit the value of autopsy reports. This study aims to investigate the contribution of ...histopathology at autopsy in a major teaching hospital.
Methods and results
A total of 532 coronial autopsy reports from Manchester Royal Infirmary were analysed retrospectively. Gross and microscopic diagnoses were compared and classified as concordant, discordant, histology needed (i.e. indeterminate or unremarkable gross findings) or autolysed. Revisions made to the cause of death following histopathology were categorised as: altered direct cause of death, altered indirect cause of death, concordant with supportive information, irrelevant or inconclusive. The study was limited to brain, heart, kidney, liver, lung and spleen. Histopathology had been requested in 141 cases (27%), which were further analysed. The greatest discordance between gross and microscopic findings was observed in the lung (11.6%). The organs most frequently requiring histopathology to provide a diagnosis were the kidney and lung, at 52.8 and 28.2%, respectively. Alterations were made to the direct cause of death in 45% of cases where histopathology was taken; it provided additional or supportive information in a further 38%. Diagnoses of primary malignancy had a sensitivity of 74% confidence interval (CI) = 0.59–0.86 and bronchopneumonia had a sensitivity of 45% (CI = 0.29–0.62).
Conclusion
Histopathology has a major impact on the interpretation of organ pathology and determining a cause of death at autopsy.
In 2013 March, a flaring episode from the Crab Nebula lasting ~2 weeks was detected by Fermi-LAT (Large Area Telescope on board the Fermi Gamma-ray Space Telescope). The Very Energetic Radiation ...Imaging Telescope Array System (VERITAS) provides simultaneous observations throughout this period. During the flare, Fermi-LAT detected a 20 fold increase in flux above the average synchrotron flux >100 MeV seen from the Crab Nebula. Simultaneous measurements with VERITAS are consistent with the non-variable long-term average Crab Nebula flux at TeV energies. Assuming a linear correlation between the very high energy flux change >1 TeV and the flux change seen in the Fermi-LAT band >100 MeV during the period of simultaneous observations, the linear correlation factor can be constrained to be at most 8.6 x 10 super(-3) with 95% confidence.
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