Standardized Criteria for Identification of Cardiac Tamponade on Non-Electrocardiogram-gated Computed Tomography: Correlation With Echocardiographic Findings

PURPOSE

To identify imaging parameters that can help in the diagnosis of cardiac tamponade on non-electrocardiogram (ECG)-gated computed tomography (CT) of the chest.

MATERIALS AND METHODS

Retrospective analysis of 64 patients who had undergone CT and echocardiography for evaluation of cardiac tamponade. Of 64 patients, 34 were diagnosed with tamponade and underwent pericardiocentesis for further diagnosis and treatment. CT measurements obtained were: pericardial effusion (PeEff) pocket size in 6 locations (anterior, posterior, superior, inferior, right, and left lateral), pericardial thickening, diameters of the coronary sinus, upper superior vena cava, lower superior vena cava, and inferior vena cava. In addition, cardiac chamber sizes were measured. Subjective assessment of coronary sinus compression, pericardial enhancement, and pericardial thickening were also recorded.

RESULTS

Measurement of the sum of the right lateral and left lateral PeEff thickness resulted in 91.2% sensitivity and 86.7% specificity for cardiac tamponade with a threshold of 30 mm (receiver-operating characteristic area under the curve=0.94 [0.84 to 0.98], P <0.0001). Using the combination of inferior PeEff >16 mm, sum of right lateral and left lateral PeEff>30 mm, and presence of pericardial thickening resulted in 56% sensitivity and 100% specificity and positive predictive value for the determination of cardiac tamponade.

CONCLUSIONS

Our study suggests that CT measurements related to PeEff size and thickness aid in the diagnosis of cardiac tamponade.

Sustainable volume sweep imaging lung teleultrasound in Peru: Public health perspectives from a new frontier in expanding access to imaging

Background

Pulmonary disease is a common cause of morbidity and mortality, but the majority of the people in the world lack access to diagnostic imaging for its assessment. We conducted an implementation assessment of a potentially sustainable and cost-effective model for delivery of volume sweep imaging (VSI) lung teleultrasound in Peru. This model allows image acquisition by individuals without prior ultrasound experience after only a few hours of training.

Methods

Lung teleultrasound was implemented at 5 sites in rural Peru after a few hours of installation and staff training. Patients were offered free lung VSI teleultrasound examination for concerns of respiratory illness or research purposes. After ultrasound examination, patients were surveyed regarding their experience. Health staff and members of the implementation team also participated in separate interviews detailing their views of the teleultrasound system which were systematically analyzed for key themes.

Results

Patients and staff rated their experience with lung teleultrasound as overwhelmingly positive. The lung teleultrasound system was viewed as a potential way to improve access to imaging and the health of rural communities. Detailed interviews with the implementation team revealed obstacles to implementation important for consideration such as gaps in lung ultrasound understanding.

Conclusions

Lung VSI teleultrasound was successfully deployed to 5 health centers in rural Peru. Implementation assessment revealed enthusiasm for the system among members of the community along with important areas of consideration for future teleultrasound deployment. This system offers a potential means to increase access to imaging for pulmonary illness and improve the health of the global community.

Geographical variability of bacterial communities of cryoconite holes of Andean glaciers

Cryoconite holes, ponds full of melting water with sediment on the bottom, are hotspots of biodiversity on glacier surfaces and host dynamic micro-ecosystems. They have been extensively investigated in different areas of the world (e.g., the Arctic, Antarctic, Alps, and Himalaya), but so far no study has described the bacterial communities of the glaciers in the Andes, the world's longest mountain range. In this study, we describe the bacterial communities of three small (< 2 km²) high-elevation (< 4200 m a.s.l.) glaciers of the Central Andes (Iver, East Iver and Morado glaciers) and two large (> 85 km²) glaciers of the Patagonian Andes (Exploradores and Perito Moreno glaciers) whose ablation tongues reach low altitude (< 300 m a.s.l.). Results show that the bacterial communities were generally similar to those observed in the cryoconite holes of other continents, but with few cyanobacteria (0.5% of sequences). The most abundant orders were Betaproteobacteriales, Cytophagales, Chitinophagales, Acetobacterales, Frankiales, Armatimonadales, Sphingobacteriales, Rhizobiales, Bacteroidales, Sphingomonadales, and Micrococcales. The bacterial communities differed between glaciers and both water pH and O₂ concentration appeared to influence the bacterial community composition. This work thus provides the first description of the bacterial communities in cryoconite holes of South American glaciers.

Volume sweep imaging lung teleultrasound for detection of COVID-19 in Peru: a multicentre pilot study

OBJECTIVES

Pulmonary disease is a significant cause of morbidity and mortality in adults and children, but most of the world lacks diagnostic imaging for its assessment. Lung ultrasound is a portable, low-cost, and highly accurate imaging modality for assessment of pulmonary pathology including pneumonia, but its deployment is limited secondary to a lack of trained sonographers. In this study, we piloted a low-cost lung teleultrasound system in rural Peru during the COVID-19 pandemic using lung ultrasound volume sweep imaging (VSI) that can be operated by an individual without prior ultrasound training circumventing many obstacles to ultrasound deployment.

DESIGN

Pilot study.

SETTING

Study activities took place in five health centres in rural Peru.

PARTICIPANTS

There were 213 participants presenting to rural health clinics.

INTERVENTIONS

Individuals without prior ultrasound experience in rural Peru underwent brief training on how to use the teleultrasound system and perform lung ultrasound VSI. Subsequently, patients attending clinic were scanned by these previously ultrasound-naïve operators with the teleultrasound system.

PRIMARY AND SECONDARY OUTCOME MEASURES

Radiologists examined the ultrasound imaging to assess its diagnostic value and identify any pathology. A random subset of 20% of the scans were analysed for inter-reader reliability.

RESULTS

Lung VSI teleultrasound examinations underwent detailed analysis by two cardiothoracic attending radiologists. Of the examinations, 202 were rated of diagnostic image quality (94.8%, 95% CI 90.9% to 97.4%). There was 91% agreement between radiologists on lung ultrasound interpretation among a 20% sample of all examinations (κ=0.76, 95% CI 0.53 to 0.98). Radiologists were able to identify sequelae of COVID-19 with the predominant finding being B-lines.

CONCLUSION

Lung VSI teleultrasound performed by individuals without prior training allowed diagnostic imaging of the lungs and identification of sequelae of COVID-19 infection. Deployment of lung VSI teleultrasound holds potential as a low-cost means to improve access to imaging around the world.

Phase II study of cabazitaxel as second-third line treatment in patients with metastatic adrenocortical carcinoma

Background

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with a poor prognosis. No efficacious treatment options are currently available for patients with advanced metastatic disease with disease progression to standard etoposide, doxorubicin, cisplatin and mitotane (EDP-M) therapy. We assessed the activity and tolerability of cabazitaxel as a second/third-line approach in metastatic ACC.

Patients and methods

Patients included in this single-center, phase II study (ClinicalTrials.gov identifier NCT03257891) had disease progression to a cisplatin-containing regimen (such as EDP) plus mitotane, plus/minus a further chemotherapy line. Cabazitaxel was administered intravenously at 25 mg/m² on day 1 of a 21-day cycle, for a maximum of six cycles. The primary endpoint was a disease control rate after 4 months.

Results

From March 2018 to September 2019, 25 eligible patients were enrolled. A disease control rate after 4 months was obtained in six patients (24%). No patients attained a disease response according to RECIST 1.1, 9 patients (36%) had stable disease and 16 patients (64%) progressive disease. Median progression-free survival and overall survival were 1.5 months (range 0.3-7 months) and 6 months (range 1-22.2 months), respectively. Cabazitaxel therapy was well tolerated and only three (12%) patients developed grade 3 toxicity which were nausea in one patient (4%) and anemia in two patients (8%).

Conclusions

Cabazitaxel has a manageable toxicity profile but is poorly active as second/third-line treatment in advanced ACC patients. These results do not support further evaluation of cabazitaxel in this setting.

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Cabazitaxel is well tolerated but poorly active as second/third-line treatment in patients with advanced ACC.

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Combining RECIST and Choi criteria could be of value in the assessment of disease response to chemotherapy in ACC patients.

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Older age, elevated cortisol and LDH blood level correlate with a greater risk of death in multivariate analysis.

Lung ultrasound volume sweep imaging for respiratory illness: a new horizon in expanding imaging access

Background

Respiratory illness is a leading cause of morbidity in adults and the number one cause of mortality in children, yet billions of people lack access to medical imaging to assist in its diagnosis. Although ultrasound is highly sensitive and specific for respiratory illness such as pneumonia, its deployment is limited by a lack of sonographers. As a solution, we tested a standardised lung ultrasound volume sweep imaging (VSI) protocol based solely on external body landmarks performed by individuals without prior ultrasound experience after brief training. Each step in the VSI protocol is saved as a video clip for later interpretation by a specialist.

Methods

Dyspneic hospitalised patients were scanned by ultrasound naive operators after 2 hours of training using the lung ultrasound VSI protocol. Separate blinded readers interpreted both lung ultrasound VSI examinations and standard of care chest radiographs to ascertain the diagnostic value of lung VSI considering chest X-ray as the reference standard. Comparison to clinical diagnosis as documented in the medical record and CT (when available) were also performed. Readers offered a final interpretation of normal, abnormal, or indeterminate/borderline for each VSI examination, chest X-ray, and CT.

Results

Operators scanned 102 subjects (0–89 years old) for analysis. Lung VSI showed a sensitivity of 93% and a specificity of 91% for an abnormal chest X-ray and a sensitivity of 100% and a specificity of 93% for a clinical diagnosis of pneumonia. When any cases with an indeterminate rating on chest X-ray or ultrasound were excluded (n=38), VSI lung ultrasound showed 92% agreement with chest X-ray (Cohen’s κ 0.83 (0.68 to 0.97, p<0.0001)). Among cases with CT (n=21), when any ultrasound with an indeterminate rating was excluded (n=3), there was 100% agreement with VSI.

Conclusion

Lung VSI performed by previously inexperienced ultrasound operators after brief training showed excellent agreement with chest X-ray and high sensitivity and specificity for a clinical diagnosis of pneumonia. Blinded readers were able to identify other respiratory diseases including pulmonary oedema and pleural effusion. Deployment of lung VSI could benefit the health of the global community.

Early ecological succession patterns of bacterial, fungal and plant communities along a chronosequence in a recently deglaciated area of the Italian Alps

In this study, the early ecological succession patterns of Forni Glacier (Ortles-Cevedale group, Italian Alps) forefield along an 18-year long chronosequence (with a temporal resolution of 1 year) has been reported. Bacterial and fungal community structures were inferred by high-throughput sequencing of 16S rRNA gene and ITS, respectively. In addition, the occurrence of both herbaceous and arboreous plants was also recorded at each plot. A significant decrease of alpha-diversity in more recently deglaciated areas was observed for both bacteria and plants. Time since deglaciation and pH affected the structure of both fungal and bacterial communities. Pioneer plants could be a major source of colonization for both bacterial and fungal communities. Consistently, some of the most abundant bacterial taxa and some of those significantly varying with pH along the chronosequence (Polaromonas, Granulicella, Thiobacillus, Acidiferrobacter) are known to be actively involved in rock-weathering processes due to their chemolithotrophic metabolism, thus suggesting that the early phase of the chronosequence could be mainly shaped by the biologically controlled bioavailability of metals and inorganic compounds. Fungal communities were dominated by ascomycetous filamentous fungi and basidiomycetous yeasts. Their role as cold-adapted organic matter decomposers, due to their heterotrophic metabolism, was suggested.

Improving CT assessment for pulmonary hypertension in patients with severe aortic stenosis, correlation with right heart catheterization

PURPOSE

To identify CT parameters useful for assessment of pulmonary hypertension (PH) in patients with severe aortic stenosis (AS).

MATERIALS AND METHODS

Retrospective study of 165 patients who had undergone right heart catheterization (RHC), and CTA of the thorax for preoperative aortic valve replacement (TAVR) planning. These were divided into groups based on mean pulmonary artery (PA) pressure (mPAP) of 25 mm Hg on RHC (85 cases and 80 controls). Diameters of main pulmonary artery diameter (MPAD), left pulmonary artery (LPA), right pulmonary artery (RPA), and maximal long axis and short axis diameters of the right atrium (RA) and ventricle (RV) were measured on the axial plane. Univariate and multivariate statistical analysis was utilized to identify metrics predictive of PH.

RESULTS

MPAD, LPA, and RPA were higher in subjects with mPAP >25 mm Hg (p < 0.0001 for all). Thresholds of 30.5 mm for MPAD (68.4% sensitivity, 82.7% specificity), and 27.5 mm for LPA and RPA (LPA: 51.9% sensitivity, 78.8% specificity; RPA: 62.0% sensitivity, 78.8% specificity) provided the best discrimination of elevated mPAP. Compared to literature values for MPAD (28.9 mm in men and 26.9 mm in women), these thresholds provide lower sensitivity but greatly increased specificity. Inclusion of RA enlargement to MPAD increased specificity to 98.5%, while inclusion of RV enlargement increased specificity to 100%.

CONCLUSION

Threshold to identify PH in patients with AS using PA enlargement is higher than previously reported range for normal. Inclusion of RA and RV enlargement improves the ability of CT to more accurately identify PH in patients with AS.

Combination therapy improves vascular volume in female rats with pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a female predominant disease in which progressive vascular remodeling and vasoconstriction result in right ventricular (RV) failure and death. Most PAH patients utilize multiple therapies. In contrast, the majority of preclinical therapeutic studies are performed in male rats with a single novel drug often markedly reversing disease in the model. We sought to differentiate single drug therapy from combination therapy in female rats with severe disease. One week after left pneumonectomy, we induced PH in young female Sprague-Dawley rats with an injection of monocrotaline (45 mg/kg). Female rats were then randomized to receive combination therapy (ambrisentan plus tadalafil), ambrisentan monotherapy, tadalafil monotherapy, or vehicle. We measured RV size and function on two serial echocardiograms during the development of disease. We measured RV systolic pressure (RVSP) invasively at day 28 after monocrotaline before analyzing the vascular volume with microcomputed tomography (microCT) of the right middle lobe. RVSP was significantly lower in female rats treated with combination therapy, and combination therapy resulted in increased small vessel volume density measured by microCT compared with untreated rats. Combination-treated rats had the smallest RV end-diastolic diameter on echocardiogram as compared with the other groups. In summary, we report a female model of pulmonary hypertension that can distinguish between one and two drug therapies; this model may facilitate better preclinical drug testing for novel compounds.

Occurrence of volatile organic compounds in shallow alluvial aquifers of a Mediterranean region: Baseline scenario and ecological implications

A regional survey of eight volatile organic compounds (VOCs), namely BTEX (benzene, toluene, ethylbenzene and p-xylene) and four chlorinated aliphatic hydrocarbons (CAHs: chloroform, 1,2-dichloroethane, trichloroethene and tetrachloroethene), was carried out at 174 sites, in 17 alluvial aquifers of Abruzzo, a Mediterranean region of southern Italy, from 2004 to 2009. Frequency of detection, concentration range, spatial distribution pattern, and temporal trend of contaminant concentration in each aquifer were analyzed as well as the relationships between VOC concentrations and the total amount of precipitation during the 90days preceding each sampling date. A review of published ecotoxicological data, providing an indication of the biological risk associated with the observed levels of VOC contamination, was presented and discussed. BTEX concentrations were under detection limits in all the investigated aquifers, indicating absence of contamination. In contrast, CAH contamination occurred in 14 out of 17 aquifers. The two most frequently detected compounds were chloroform and tetrachloroethene. No significant temporal trend was observed for chloroform and tetrachloroethene concentrations during the six years of observation, indicating the persistence of stable contaminations, except for some slightly decreasing trends observed in three out of 17 aquifers. In four aquifers chloroform and tetrachloroethene concentrations increased with precipitations in the preceding months. Spatial patterns of contamination differed among aquifers, indicating highly complex contaminant distributions at aquifer scale not related to single-plume geometries. Patterns of contamination by chloroform and tetrachloroethene in the most urbanized aquifers were likely associated with multiple sources of VOCs not clearly detectable at the scale used in this study. In five out of 17 aquifers, chloroform and tetrachloroethene co-occurred at concentrations that are lethal to groundwater-dwelling organisms under a short exposure period (four days). Future studies should therefore consider the possibility that in the other aquifers groundwater-dwelling organisms might be physiologically damaged by sublethal VOC concentrations.

MHC genotype predicts mate choice in the ring-necked pheasant Phasianus colchicus

Females of several vertebrate species selectively mate with males on the basis of the major histocompatibility complex (MHC) genes. As androgen-mediated maternal effects have long-lasting consequences for the adult phenotype, both mating and reproductive success may depend on the combined effect of MHC genotype and exposure to androgens during early ontogeny. We studied how MHC-based mate choice in ring-necked pheasants (Phasianus colchicus) was influenced by an experimental in ovo testosterone (T) increase. There was no conclusive evidence of in ovo T treatment differentially affecting mate choice in relation to MHC genotype. However, females avoided mating with males with a wholly different MHC genotype compared with males sharing at least one MHC allele. Females also tended to avoid mating with MHC-identical males, though not significantly so. These findings suggest that female pheasants preferred males with intermediate MHC dissimilarity. Male MHC heterozygosity or diversity did not predict the expression of ornaments or male dominance rank. Thus, MHC-based mating preferences in the ring-necked pheasant do not seem to be mediated by ornaments' expression and may have evolved mainly to reduce the costs of high heterozygosity at MHC loci for the progeny, such as increased risk of autoimmune diseases or disruption of coadapted gene pools.

Rapid change in host use of the common cuckoo Cuculus canorus linked to climate change

Parasites require synchrony with their hosts so if host timing changes with climate change, some parasites may decline and eventually go extinct. Residents and short-distance migrant hosts of the brood parasitic common cuckoo, Cuculus canorus, have advanced their phenology in response to climate change more than long-distance migrants, including the cuckoo itself. Because different parts of Europe show different degrees of climate change, we predicted that use of residents or short-distance migrants as hosts should have declined in areas with greater increase in spring temperature. Comparing relative frequency of parasitism of the two host categories in 23 European countries before and after 1990, when spring temperatures in many areas had started to increase, we found that relative parasitism of residents and short-distance migrants decreased. This change in host use was positively related to increase in spring temperature, consistent with the prediction that relative change in phenology for different migrant classes drives host-use patterns. These findings are consistent with the hypothesis that climate change affects the relative abundance of different host races of the common cuckoo.

Sex-related variation in migration phenology in relation to sexual dimorphism: a test of competing hypotheses for the evolution of protandry

Timing of arrival/emergence to the breeding grounds is under contrasting natural and sexual selection pressures. Because of differences in sex roles and physiology, the balance between these pressures on either sex may differ, leading to earlier male (protandry) or female (protogyny) arrival. We test several competing hypotheses for the evolution of protandry using migration data for 22 bird species, including for the first time several monochromatic ones where sexual selection is supposedly less intense. Across species, protandry positively covaried with sexual size dimorphism but not with dichromatism. Within species, there was weak evidence that males migrate earlier because, being larger, they are less susceptible to adverse conditions. Our results do not support the 'rank advantage' and the 'differential susceptibility' hypotheses, nor the 'mate opportunity' hypothesis, which predicts covariation of protandry with dichromatism. Conversely, they are compatible with 'mate choice' arguments, whereby females use condition-dependent arrival date to assess mate quality.

MRI Post-vertebroplasty

PURPOSE

Percutaneous vertebroplasty (PVP), first described by Hervè Deramond in 1984, is an interventional procedure for the treatment of aggressive vertebral angioma. The aim of this study was to evaluate magnetic resonance imaging (MRI) patterns in the affected vertebrae before and after vertebroplasty by determining changes in signal intensity and size and distribution of bone cement within the vertebra at follow-up carried out at 1 week, 6 months and 12 months.

MATERIALS AND METHODS

Fourteen patients were examined using MRI, for a total of 41 treated vertebrae; MRI was performed with a 0.5-Tesla (T) superconductive magnet (SIGNA GE).

RESULTS

MRI patterns following vertebroplasty are mainly characterised by the signal produced by the areas surrounding the cement and by the cement itself. There is little effect on the size of the treated vertebra. Acrylic cement appears as an intraspongy focal area of T1 and T2 hypointensity that is mostly oval (34%) or rounded (26.8%); this appearance tends to become stable 6 months after treatment. The area surrounding the cement appears hypointense on T1 and hyperintense on T2, a likely expression of bone marrow oedema; this signal alteration tends to disappear gradually.

CONCLUSIONS

In pre- and post-vertebroplasty imaging, MRI is regarded as the reference standard for correct evaluation of both container and content. Awareness of cement changes over time and of the reaction of the surrounding bone tissue is crucial for correct assessment of post-vertebroplasty images.

Offspring sexual dimorphism and sex-allocation in relation to parental age and paternal ornamentation in the barn swallow

We analysed the morphology of nestling barn swallows (Hirundo rustica) in relation to their sex, and laying and hatching order. In addition, we studied sex-allocation in relation to parentage, parental age and expression of a secondary sexual character of fathers. Molecular sexing was conducted using the sex chromosome-linked avian CHD1 gene. Sex of the offspring was not associated with laying or hatching order. None of nine morphological, serological and immunological variables varied in relation to offspring sex. Sexual dimorphism did not vary in relation to parental age and expression of a paternal secondary sexual character. The proportion of sons declined with brood size. Individual males and females had a similar proportion of sons during consecutive breeding years. The proportion of sons of individual females declined with age, but increased with the expression of a secondary sexual character of their current mate. The generalized lack of variation in sexual dimorphism among nestlings may suggest that barn swallows do not differentially invest in sons vs. daughters. Alternatively, male offspring may require different parental effort compared to their female siblings in order to attain the same morphological state. The lack of variation in offspring sexual dimorphism with paternal ornamentation suggests no adjustment of overall parental effort in relation to reproductive value of the two sexes. However, male-biased sex ratio among offspring of highly ornamented males may represent an adaptive sex-allocation strategy because the expression of male ornaments is heritable and highly ornamented males are at a sexual selection advantage.

High-resolution magnetic resonance angiography of the internal carotid artery: 2D vs 3D TOF in stenotic disease

The aim of this study was to compare high-resolution 2D TOF with high-resolution 3D TOF in the study of internal carotid artery disease. Sixty-four patients with clinical signs of cerebrovascular insufficiency were studied with a superconductive 1.5 T magnet using two techniques: 2D and 3D TOF. Digital subtraction angiography (DSA) was the gold standard. The 2D TOF technique was performed using the following parameters: TR/TE/FA/MA 49 ms/9 ms/60 degrees/512 x 256; the 3D TOF was performed with the following parameters: TR/TE/FA/MA 50 ms/8 ms/20 degrees/512 x 256. The 2D TOF agreed with DSA in 116 of 128 diagnostic judgments (90%) and overestimated seven times. The 3D TOF technique agreed with DSA in 125 of 128 diagnostic judgments (97%) with one overestimation and two underestimations. There was no statistically significant difference (P < 0.05) between the two different techniques. Our study confirms the high reliability of the methodology carried out with the high-resolution 2D and 3D technique.

Magnetic resonance angiography and colour-Doppler sonography in the evaluation of abdominal aortic aneurysms

This prospective study was aimed at comparing the diagnostic accuracy of magnetic resonance angiography (MRA) with colour-Doppler ultrasonography (colour-Doppler US) in the assessment of abdominal aortic aneurysms (AAA). Twenty patients with abdominal aortic aneurysms underwent MRA, colour-Doppler US, digital subtraction angiography (DSA) and CT. The MRA technique and colour-Doppler findings were compared with DSA as well as surgical and pathological findings, which were considered as the gold standard. In 6 patients who refused surgery, CT and DSA were considered as the gold standard. The MRA technique always correctly assessed the size and site of the aneurysms, the involvement of the renal and common iliac arteries, the course of the left renal vein, the thrombotic component and the calcifications. Colour-Doppler US always correctly assessed the size and site of the aneurysms, the thrombotic component and calcifications and the involvement of the iliac arteries. Our preliminary results suggest that MRA together with colour-Doppler US represents a valid alternative to invasive imaging in the assessment of AAA.