Postmortem examination of human fetuses: a comparison of 2-dimensional ultrasound with invasive autopsy

OBJECTIVE: To compare the diagnostic usefulness of postmortem ultrasound with invasive autopsy in fetuses at different gestational ages. METHODS: We performed postmortem 2-dimensional ultrasound on 163 fetuses at 13-42 weeks gestation, blinded to clinical details. Logistic regression analysis was used to investigate the effect on non-diagnostic results of gestational age during postmortem ultrasound, presence of maceration, and cause of death. In 123 cases where invasive autopsy was available, the diagnostic accuracy of ultrasound in detecting major organ abnormalities was evaluated, using invasive autopsy as a gold standard. RESULTS: For the fetal brain, a non-diagnostic result was found in 17 (39.5%) of 43 fetuses with maceration and was significantly more common as compared to fetuses without maceration (24 [20.0%] of 120 fetuses [p=0.013]). For the fetal thorax, a non-diagnostic result was found in 15 (34.1%) of 44 fetuses at <20 weeks of gestation and in 13 (10.9%) of 119 fetuses at ≥20 weeks (p<0.001). For the heart and abdominal organs no association was demonstrated with the tested variables. For fetuses <20 weeks, specificity was 83.3% for brain anomalies, 68.6% for the thorax, and 77.4% for the heart. For fetuses ≥20 weeks, sensitivity and specificity were, respectively, 61.9% and 74.2% for the brain, 29.5% and 87.0% for the thorax, and 57.1% and 76.9% for the heart. Sensitivity was 60.7% and specificity 75.8% for fetal abdominal organs, mainly the kidneys, irrespective of gestational age. CONCLUSION: Although maceration may lead to failure in some cases, postmortem ultrasound reaches diagnostically acceptable levels for brain and abdominal organs, compared with conventional autopsy. It may therefore play a role as a first-line examination before other virtual autopsy techniques are indicated

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

Study of b-hadron decays to Λc^+h-h' final states

Decays of Ξ − b and Ω − b baryons to Λ + c h −h ′− final states, with h −h ′− being π −π −, K−π\ud − and K−K− meson pairs, are searched for using data collected with the LHCb detector. The data sample studied corresponds to an integrated luminosity of 8.7 fb−1 of pp collisions collected at centre-of-mass energies √ s = 7, 8 and 13 TeV. The products of the relative branching fractions and fragmentation fractions for each signal mode, relative to the B− → Λ + c pπ− mode, are measured, with Ξ − b → Λ + c K−π −, Ξ − b → Λ + c K−K− and Ω − b → Λ + c K−K− decays being observed at over 5 σ significance. The Ξ − b → Λ + c K−π − mode is also used to measure the Ξ − b production asymmetry, which is found to be consistent with zero. In addition, the B− → Λ + c pK− decay is observed for the first time, and its branching fraction is measured relative to that of the B− → Λ + c pπ− mode

The LHCb upgrade I

The LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

Postmortem fetal imaging: a prospective blinded comparison study of 2-dimensional ultrasound with MR imaging

OBJECTIVE: To compare the diagnostic rate and diagnostic accuracy of 3 Tesla (T) postmortem magnetic resonance imaging (PMMRI) and postmortem ultrasound (PMUS) in an unselected population. METHODS: In a blinded manner, we prospectively performed 3T PMMRI and PMUS on 160 unselected fetuses at 13-41 weeks of gestation. All imaging was reported according to a pre-specified template, for 5 anatomical regions: brain, thorax, heart, abdomen and spine. McNemar test for paired proportion was used to compare the non-diagnostic results rates of PMUS and PMMRI. When diagnostic, sensitivity, specificity and concordance rates for each anatomical region were calculated, using conventional autopsy as the reference standard. RESULTS: 3T PMMR performed significantly better than PMUS overall. Specifically, for the brain (7 non-diagnostic vs 43/160; 4.4% vs 26.9%; p<0.001), thorax (8 non-diagnostic vs 27/155; 5.2% vs 17.4%; p<0.001), heart (6 non-diagnostic vs 48/157; 3.8% vs 30.6%; p<0.001) and abdomen (5 non-diagnostic vs 37/157; 3.2% vs 23.6%; p<0.001). However, when diagnostic, we found similar accuracy for PMUS and PMMRI, with no difference in sensitivity or specificity, and similar concordance (PMUS 81.8-96.5%; PMMRI 81.6-99.1%). CONCLUSION: PMMRI performed significantly better than PMUS in this population, mainly due to a lower non-diagnostic study rate. PMMRI remains the first line imaging investigation for perinatal autopsy, but PMUS could be considered where MRI is not available, accepting a higher non-diagnostic rate. This article is protected by copyright. All rights reserved