Computed tomographic indications for occult skull fractures in paediatric head trauma diagnosed at the time of wound closure under general anaesthesia

Children with head injuries commonly present to the emergency department with forehead lacerations, and are frequently referred to the oral and maxillofacial team. Assessing the Glasgow coma scale (GCS) and neurological status of these patients is particularly challenging and there remains marked ambiguity regarding the use of computed tomographic (CT) imaging in children who have no obvious signs of traumatic brain injury. We present a case series of three patients who presented to our unit with forehead lacerations following a fall. All had a normal GCS, no obvious neurological signs, and all were listed for wound closure under general anaesthesia. Intraoperatively they were found to have underlying skull fractures that necessitated emergency CT whilst under general anaesthesia. Retrospective analysis was performed. Current guidelines and the literature were reviewed to identify factors that may help to identify occult skull fractures in the context of paediatric head trauma. Despite the subsequent discovery of skull fractures under general anaesthesia, none of our patients would have satisfied the present absolute indications for CT in the current guidelines. A number of helpful factors are not common in the UK guidelines but are present in others, including the presence of an appreciable haematoma and lacerations greater than 5 cm, amongst others. The assessment of paediatric patients with head trauma often remains a challenge when assessing for features such as headache, focal neurology, and amnesia. A high index of suspicion, formal examination under anaesthesia, and communication with the radiology department, are imperative if we are to avoid missing an occult injury that could potentially result in brain injury.

Anatomical relationship of pterygoid process pneumatization and vidian canal

Introduction

The vidian canal acts as landmark for the identification of the petrous carotid artery, especially during extended endoscopic endonasal approaches in cranial base surgeries. In order to localize the canal and to understand the relationship of pneumatization of pterygoid process to the type of vidian canal, this study was designed.

Objectives

The objective was to describe the anatomical relationship of pneumatization of the pterygoid process with types of vidian canal. The length of vidian canal, relationship to medial plate of pterygoid process and relationship to the petrous part of internal carotid artery were evaluated.

Methods

Head computer tomography scans of 52 individuals for suspected paranasal pathology were studied. The degree of sphenoid sinus pneumatization, pterygoid process pneumatization and types of vidian canal (type 1, 2 and 3) were noted. The length of vidian canal, distance from the plane of medial pterygoid plate and relation of vidian canal to the junction of petrous and Gasserian (ascending) part of internal carotid artery was noted.

Results

46 (92%) sphenoid sinuses were of the sellar variety. Out of 104 sides that were studied, 57 sides demonstrated a pneumatised pterygoid process and 47 were not pneumatised. In 49 sides (47.1%) the vidian canal was on the same plane as that of the medial pterygoid plate in the coronal section. The vidian canal partially protruded into the sphenoid sinus (type 2) was the most common type (50.9%), found both on right and left sides. There is a statistically significant association between the pterygoid process pneumatization and occurrence of type 2 and type 3 vidian canal configuration. The average length of the vidian canal was 16.16 ± 1.8 mm. In 96 sides, the anterior end of vidian canal was inferolateral to petrous part of internal carotid artery in the coronal plane.

Conclusion

Pneumatization of the pterygoid process indicates either type 2 or type 3 vidian canal configuration.

Vitamin K for kidney transplant organ recipients: investigating vessel stiffness (ViKTORIES): study rationale and protocol of a randomised controlled trial

BACKGROUND

Renal transplant recipients (RTRs) exhibit increased vascular stiffness and calcification; these parameters are associated with increased cardiovascular risk. Activity of endogenous calcification inhibitors such as matrix gla protein (MGP) is dependent on vitamin K. RTRs commonly have subclinical vitamin K deficiency. The Vitamin K in kidney Transplant Organ Recipients: Investigating vEssel Stiffness (ViKTORIES) study assesses whether vitamin K supplementation reduces vascular stiffness and calcification in a diverse population of RTR.

METHODS AND ANALYSIS

ViKTORIES (ISRCTN22012044) is a single-centre, phase II, parallel-group, randomised, double-blind, placebo-controlled trial of the effect of vitamin K supplementation in 90 prevalent RTR. Participants are eligible if they have a functioning renal transplant for >1 year. Those on warfarin, with atrial fibrillation, estimated glomerular filtration rate <15 mL/min/1.73 m2 or contraindications to MRI are excluded. Treatment is with vitamin K (menadiol diphosphate) 5 mg three times per week for 1 year or matching placebo. All participants have primary and secondary endpoint measures at 0 and 12 months. The primary endpoint is ascending aortic distensibility on cardiac MR imaging. Secondary endpoints include vascular calcification (coronary artery calcium score by CT), cardiac structure and function on MR, carotid-femoral pulse wave velocity, serum uncarboxylated MGP, transplant function, proteinuria and quality of life. The study is powered to detect 1.0×10-3 mm Hg-1 improvement in ascending aortic distensibility in the vitamin K group relative to placebo at 12 months. Analyses will be conducted as between-group differences at 12 months by intention to treat.

DISCUSSION

This trial may identify a novel, inexpensive and low-risk treatment to improve surrogate markers of cardiovascular risk in RTR.

CT imaging prior to transcatheter aortic valve implantation in the UK

Objective

This cross-sectional observational study sought to describe variations in CT in the context of transcatheter aortic valve implantation (CT-TAVI) as currently performed in the UK.

Methods

408 members of the British Society of Cardiovascular Imaging were invited to complete a 27-item online CT-TAVI survey.

Results

47 responses (12% response rate) were received from 40 cardiac centres, 23 (58%) of which performed TAVI on-site (TAVI centres). Only six respondents (13%) performed high-volume activity (>200 scans per year) compared with 13 (28%) performing moderate (100–200 scans per year) and 27 (59%) performing low (0–99 scans per year) volume activity. Acquisition protocols varied (41% retrospective, 12% prospective with wide padding, 47% prospective with narrow padding), as did the phase of reporting (45% systolic, 37% diastolic, 11% both, 6% unreported). Median dose length product was 675 mGy.cm (IQR 477–954 mGy.cm). Compared with non-TAVI centres, TAVI centres were more likely to report minimum iliofemoral luminal diameter (n=25, 96% vs n=7, 58%, p=0.003) and optimal tube angulation for intervention (n=12, 46% vs n=1, 8%, p=0.02).

Conclusions

This national survey formally describes current CT-TAVI practice in the UK. High-volume activity was only present at one in seven cardiac CT centres. There is wide variation in scan acquisition, scan reporting and radiation dose exposure in cardiac CT centres.

Structural manipulations of a shelter resource reveal underlying preference functions in a shell-dwelling cichlid fish

Many animals can modify the environments in which they live, thereby changing the selection pressures they experience. A common example of such niche construction is the use, creation or modification of environmental resources for use as nests or shelters. Because these resources often have correlated structural elements, it can be difficult to disentangle the relative contribution of these elements to resource choice, and the preference functions underlying niche-construction behaviour remain hidden. Here, we present an experimental paradigm that uses 3D scanning, modelling and printing to create replicas of structures that differ with respect to key structural attributes. We show that a niche-constructing, shell-dwelling cichlid fish, Neolamprologus multifasciatus, has strong open-ended preference functions for exaggerated shell replicas. Fish preferred shells that were fully intact and either enlarged, lengthened or had widened apertures. Shell intactness was the most important structural attribute, followed by shell length, then aperture width. We disentangle the relative roles of different shell attributes, which are tightly correlated in the wild, but nevertheless differentially influence shelter choice and therefore niche construction in this species. We highlight the broad utility of our approach when compared with more traditional methods (e.g. two-choice tasks) for studying animal decision-making in a range of contexts.

Inner ear sensory system changes as extinct crocodylomorphs transitioned from land to water

Major evolutionary transitions, in which animals develop new body plans and adapt to dramatically new habitats and lifestyles, have punctuated the history of life. The origin of cetaceans from land-living mammals is among the most famous of these events. Much earlier, during the Mesozoic Era, many reptile groups also moved from land to water, but these transitions are more poorly understood. We use computed tomography to study changes in the inner ear vestibular system, involved in sensing balance and equilibrium, as one of these groups, extinct crocodile relatives called thalattosuchians, transitioned from terrestrial ancestors into pelagic (open ocean) swimmers. We find that the morphology of the vestibular system corresponds to habitat, with pelagic thalattosuchians exhibiting a more compact labyrinth with wider semicircular canal diameters and an enlarged vestibule, reminiscent of modified and miniaturized labyrinths of other marine reptiles and cetaceans. Pelagic thalattosuchians with modified inner ears were the culmination of an evolutionary trend with a long semiaquatic phase, and their pelagic vestibular systems appeared after the first changes to the postcranial skeleton that enhanced their ability to swim. This is strikingly different from cetaceans, which miniaturized their labyrinths soon after entering the water, without a prolonged semiaquatic stage. Thus, thalattosuchians and cetaceans became secondarily aquatic in different ways and at different paces, showing that there are different routes for the same type of transition.

Inner ear sensory system changes as extinct crocodylomorphs transitioned from land to water

Major evolutionary transitions, in which animals develop new body plans and adapt to dramatically new habitats and lifestyles, have punctuated the history of life. The origin of cetaceans from land-living mammals is among the most famous of these events. Much earlier, during the Mesozoic Era, many reptile groups also moved from land to water, but these transitions are more poorly understood. We use computed tomography to study changes in the inner ear vestibular system, involved in sensing balance and equilibrium, as one of these groups, extinct crocodile relatives called thalattosuchians, transitioned from terrestrial ancestors into pelagic (open ocean) swimmers. We find that the morphology of the vestibular system corresponds to habitat, with pelagic thalattosuchians exhibiting a more compact labyrinth with wider semicircular canal diameters and an enlarged vestibule, reminiscent of modified and miniaturized labyrinths of other marine reptiles and cetaceans. Pelagic thalattosuchians with modified inner ears were the culmination of an evolutionary trend with a long semiaquatic phase, and their pelagic vestibular systems appeared after the first changes to the postcranial skeleton that enhanced their ability to swim. This is strikingly different from cetaceans, which miniaturized their labyrinths soon after entering the water, without a prolonged semiaquatic stage. Thus, thalattosuchians and cetaceans became secondarily aquatic in different ways and at different paces, showing that there are different routes for the same type of transition.

Feasibility Study of Advanced Cardiovascular Screening in Middle-Aged Patients with Diabetes

Purpose

Cardiovascular mortality remains high among patients with diabetes compared with the general population. The primary aim was to evaluate the interest in and demand for advanced cardiovascular screening in patients with diabetes; the secondary aim was to explore its efficiency in detecting unprotected subclinical cardiovascular disease (CVD).

Patients and Methods

In a cross-sectional design, randomly selected 40–60-year-old men and women with diabetes were invited to the screening trial. Screening encompassed (1) a comprehensive medical interview; (2) non-contrast computed tomography scanning to quantify coronary artery and aortic valve calcification, to measure left atrial size, to assess heart rhythm and to detect aortic and iliac dilatations; (3) ankle and brachial blood pressure measurements; and (4) blood and urine samples for measurements of HbA_1c, lipid profile, renal function, NT-pro B-type natriuretic peptide (pro-BNP) and albuminuria. Primary outcome was participation rate; secondary outcome was rate of unprotected subclinical CVD.

Results

Of 465 invited patients, 191 (41.1%) attended screening. The participation rate was 40% (95% CI:33–47) for males and 42% (95% CI:36–48) for females. Twenty-four patients were excluded due to previous CVD. The remaining patients’ mean age was 52 years; 58% were males. Subclinical CVD was found in 64%, with a male preponderance (males 75% (95% CI:66–83; females 49% (95% CI:37–60)). Presence of severe coronary artery calcification (score ≥ 400) showed a male preponderance (males 19% (95% CI:12–27); females 7% (95% CI:3–16)). Aortic valve calcification, enlarged left atrial volume, atrial fibrillation, aortic dilatations, peripheral artery disease or increased pro-BNP were uncommon, and without any sex differences. Unprotected subclinical CVD was very common, and medical treatment was intensified in 60% (95% CI:53–68) of patients.

Conclusion

We propose a feasible cardiovascular screening examination from which middle-aged patients with diabetes may benefit. However, the participation rate may be too low to warrant screening.

The diagnostic value of a seven-autoantibody panel and a nomogram with a scoring table for predicting the risk of non-small-cell lung cancer

The early detection of non-small-cell lung cancer (NSCLC) remains a common concern. The aim of our study was to validate the diagnostic value of a seven-autoantibody (7-AAB) panel compared with radiological diagnosis for NSCLC. We constructed a nomogram and a scoring table based on the 7-AAB panel's result to predict the risk of NSCLC. We prospectively enrolled 268 patients who presented with radiological lesions and underwent both the 7-AAB panel test and pathological diagnosis by surgical resection. A comparison between the 7-AAB panel and radiological diagnosis was performed. A nomogram and a scoring table based on the 7-AAB panel's result to predict the risk of NSCLC were constructed and internally validated. The 7-AAB panel test had a specificity of 90.2% and a positive predictive value (PPV) of 92.7%, which were significantly higher than those of the radiological diagnosis. The 7-AAB panel also showed a preferable sensitivity in patients with early-stage disease. Seven factors, including the 7-AAB panel results, were integrated into the nomogram. For more convenient application, we formulated a scoring table based on the nomogram. The area under the receiver operating characteristic curve was 0.840 and 0.860 in the training group and validation group, respectively, which was higher than that using the 7-AAB panel or radiological diagnosis alone. This study reveals that our 7-AAB panel has clinical value in the diagnosis of NSCLC. The utility of our nomogram and the scoring table indicated that they have the potential to assist clinicians in avoiding unnecessary treatment or needless follow-up.

Effects of outdoor ranging on external and internal health parameters for hens from different rearing enrichments

In Australia, free-range layer pullets are typically reared indoors, but adult layers go outdoors, and this mismatch might reduce adaptation in laying environments. Enrichments during rearing may optimise pullet development and subsequent welfare as adult free-range hens. In the outdoor environment, hens may have greater opportunities for exercise and natural behaviours which might contribute to improved health and welfare. However, the outdoor environment may also result in potential exposure to parasites and pathogens. Individual variation in range use may thus dictate individual health and welfare. This study was conducted to evaluate whether adult hens varied in their external and internal health due to rearing enrichments and following variation in range use. A total of 1386 Hy-Line Brown^® chicks were reared indoors across 16 weeks with three enrichment treatments including a control group with standard housing conditions, a novelty group providing novel objects that changed weekly, and a structural group with custom-designed structures to increase spatial navigation and perching. At 16 weeks of age the pullets were moved to a free-range system and housed in nine identical pens within their rearing treatments. All hens were leg-banded with microchips and daily ranging was assessed from 25 to 64 weeks via radio-frequency identification technology. At 64–65 weeks of age, 307 hens were selected based on their range use patterns across 54 days up to 64 weeks: indoor (no ranging), low outdoor (1.4 h or less daily), and high outdoor (5.2–9 h daily). The external and internal health and welfare parameters were evaluated via external assessment of body weight, plumage, toenails, pecking wounds, illness, and post-mortem assessment of internal organs and keel bones including whole-body CT scanning for body composition. The control hens had the lowest feather coverage (p < 0.0001) and a higher number of comb wounds (P = 0.03) than the novelty hens. The high outdoor rangers had fewer comb wounds than the indoor hens (P = 0.04), the shortest toenails (p < 0.0001) and the most feather coverage (p < 0.0001), but lower body weight (p < 0.0001) than the indoor hens. High outdoor ranging decreased both body fat and muscle (both p < 0.0001). The novelty group had lower spleen weights than the control hens (P = 0.01) but neither group differed from the structural hens. The high outdoor hens showed the highest spleen (P = 0.01) and empty gizzard weights (P = 0.04). Both the rearing enrichments and ranging had no effect on keel bone damage (all P ≥ 0.19). There were no significant interactions between rearing treatments and ranging patterns for any of the health and welfare parameters measured in this study (P ≥ 0.07). Overall, rearing enrichments had some effects on hen health and welfare at the later stages of the production cycle but subsequent range use patterns had the greatest impact.

Acute alcohol intoxication as a confounding factor for mild traumatic brain injury

BACKGROUND

Acute alcohol intoxication is universally considered a risk factor for traumatic brain injury (TBI), therefore an indication for head CT scan. There is no evidence in the literature for this attitude. Aim of this study is to assess the need for head CT scan in acutely alcohol-intoxicated subjects with mTBI and the role of Glasgow coma scale (GCS) score in this kind of patients.

METHODS

We retrospectively analyzed all 3358 consecutive patients presenting to our department in Switzerland, with TBI as chief complaint between January 2014 and January 2018.

RESULTS

Alcohol was a statistically significant factor for presentation with a GCS score lower than 15. As for bleedings in mild TBI patients, the results were somewhat contradictory with GCS 15 patients showing a higher percentage of hemorrhages than GCS 14 patients. By dividing alcohol-intoxicated subjects into groups per blood alcohol concentration, the higher was the alcohol level, the lower the GCS score.

CONCLUSIONS

We can affirm that GCS score is underestimated in acutely intoxicated head trauma patients. In this kind of patient, alcohol is a confounding factor and mild TBI could be safely managed by watchful waiting.

Neurosensory and Sinus Evolution as Tyrannosauroid Dinosaurs Developed Giant Size: Insight from the Endocranial Anatomy of Bistahieversor sealeyi

Tyrannosaurus rex and other tyrannosaurid dinosaurs were apex predators during the latest Cretaceous, which combined giant size and advanced neurosensory systems. Computed tomography (CT) data have shown that tyrannosaurids had a trademark system of a large brain, large olfactory bulbs, elongate cochlear ducts, and expansive endocranial sinuses surrounding the brain and sense organs. Older, smaller tyrannosauroid relatives of tyrannosaurids developed some, but not all, of these features, raising the hypothesis that tyrannosaurid-style brains evolved before the enlarged tyrannosaurid-style sinuses, which might have developed only with large body size. This has been difficult to test, however, because little is known about the brains and sinuses of the first large-bodied tyrannosauroids, which evolved prior to Tyrannosauridae. We here present the first CT data for one of these species, Bistahieversor sealeyi from New Mexico. Bistahieversor had a nearly identical brain and sinus system as tyrannosaurids like Tyrannosaurus, including a large brain, large olfactory bulbs, reduced cerebral hemispheres, and optic lobes, a small tab-like flocculus, long and straight cochlear ducts, and voluminous sinuses that include a supraocciptal recess, subcondyar sinus, and an anterior tympanic recess that exits the braincase via a prootic fossa. When characters are plotted onto tyrannosauroid phylogeny, there is a two-stage sequence in which features of the tyrannosaurid-style brain evolved first (in smaller, nontyrannosaurid species like Timurlengia), followed by features of the tyrannosaurid-style sinuses (in the first large-bodied nontyrannosaurid tyrannosauroids like Bistahieversor). This suggests that the signature tyrannosaurid sinus system evolved in concert with large size, whereas the brain did not. Anat Rec, 303:1043-1059, 2020. © 2020 American Association for Anatomy.

Impact of aortic valve calcification severity on device success after transcatheter aortic valve replacement

Aortic valvular calcium score (AVCS) can identify severe aortic stenosis (AS) and provide powerful prognostic information. In severe and symptomatic AS, patients can be referred for a transcatheter aortic valve replacement (TAVR). The aim of this study was to determine whether AVCS, measured on the preoperative contrast enhanced multislice computed tomography (MSCT), is associated with device success (DS), major adverse cardiac events (MACEs) and paravalvular leak (PVL) after TAVR. Three hundred and fifty-two consecutive patients who underwent TAVR with a preoperative standardised contrast enhanced MSCT were included in the study. Valvular calcification detection was defined by adding + 100 Hounsfield Unit (HU) to mean HU determined by a region of interest placed in the contrast enhanced ascending aorta. AVCS was then indexed to the aortic annulus surface (AVCSi). Endpoints were DS and 30-day MACE according to Valve Academic Research Consortium-2 consensus document, and moderate to severe PVL. DS was obtained for 305 patients. In multivariate analysis, AVCSi was negatively and independently associated with DS: OR = 0.99, 95% CI 0.99-0.99, p = 0.03. In the subgroup analysis, this association was particularly relevant with self-expanding prostheses [n = 151 (43%), p = 0.018] and in the cases of asymmetric calcium valvular distribution [n = 283 (80%), p 0.002]. There was no association between MACE and AVCS (p = 0.953) and AVCSi (p = 0.757). PVL was positively associated with AVCS (p < 0.001) and AVCSi (p < 0.001). In conclusion, in TAVR, AVCS, measured on preoperative contrast enhanced MSCT, is significantly associated with DS and PVL, but not with 30-day MACE. Its routine use could be relevant to appreciate success chances of TAVR.

Phenotyping analysis of maize stem using micro-computed tomography at the elongation and tasseling stages

BACKGROUND

Micro-computed tomography (μCT) bring a new opportunity to accurately quantify micro phenotypic traits of maize stem, also provide comparable benchmark to evaluate its dynamic development at the different growth stages. The progressive accumulation of stem biomass brings manifest structure changes of maize stem and vascular bundles, which are closely related with maize varietal characteristics and growth stages. Thus, micro-phenotyping (μPhenotyping) of maize stems is not only valuable to evaluate bio-mechanics and water-transport performance of maize, but also yield growth-based traits for quantitative traits loci (QTL) and functional genes location in molecular breeding.

RESULT

In this study, maize stems of 20 maize cultivars and two growth stages were imaged using μCT scanning technology. According to the observable differences of maize stems from the elongation and tasseling stages, function zones of maize stem were firstly defined to describe the substance accumulation of maize stems. And then a set of image-based μPhenotyping pipelines were implemented to quantify maize stem and vascular bundles at the two stages. The coefficient of determination (R2) of counting vascular bundles was higher than 0.95. Based on the uniform contour representation, intensity-related, geometry-related and distribution-related traits of vascular bundles were respectively evaluated in function zones and structure layers. And growth-related traits of the slice, epidermis, periphery and inner zones were also used to describe the dynamic growth of maize stem. Statistical analysis demonstrated the presented method was suitable to the phenotyping analysis of maize stem for multiple growth stages.

CONCLUSIONS

The novel descriptors of function zones provide effective phenotypic references to quantify the differences between growth stages; and the detection and identification of vascular bundles based on function zones are more robust to determine the adaptive image analysis pipeline. Developing robust and effective image-based phenotyping method to assess the traits of stem and vascular bundles, is highly relevant for understanding the relationship between maize phenomics and genomics.

Construction of digital three-dimensional reconstruction model of rabbit vascular network

In order to study the construction of digital three-dimensional model of rabbit vascular network and provide a powerful basis for the model construction and image processing of human vascular network, in this study, rabbit abdominal and pelvic vessels are perfused with latex-bismuth oxide contrast agent. After that, the internal fibrous structure of the abdominal and pelvic vascular network in rabbits is studied by micro-computed tomography (Micro-CT). Angiography and post-processing software are performed. Firstly, six female rabbits are selected as the study subjects and are anesthetized by intraperitoneal injection of 12% chloral hydrate. After complete anesthesia, laparotomy is performed on the rabbits. The abdominal wall of the rabbit is cut longitudinally to expose the pelvic and abdominal cavity completely. The posterior peritoneum is found and opened. The catheter is inserted into the abdominal aorta and renal artery to complete the abdominal aorta and arterial intubation. Latex, bismuth oxide and potassium hydroxide are mixed in a ratio of 1:1:1 to form latex-bismuth oxide mixed solution as a mixed contrast agent for blood vessel perfusion. After the rabbit is perfused with mixed contrast medium, four organs, including bladder, uterus, small intestine and kidney, are selected as the research organs to construct the three-dimensional model of vascular network in this study. Finally, the above organs are scanned in vitro by micro-CT technology, and the original images of each organ are processed. Then, Mimics 17.0 software is used to build a digital three-dimensional model of the abdominal and pelvic vascular network in rabbits, obtain the information parameters of each network, and analyze the classification and diameter of blood vessels. The results show that the classification of bladder vascular network can only be divided into two levels, uterine vascular network can be divided into three levels, and small intestine and kidney vascular network can be divided into four levels. Therefore, the combination of micro-CT scanning and contrast agent can successfully construct a digital three-dimensional model of rabbit vascular network, which provides a new idea and method for the study of human abdominal and pelvic organs and physiological characteristics.

Measuring the administered dose of particles on the facial mucosa of a realistic human model

Exposure to particulate contaminants can cause serious adverse health effects. Deposition on the facial mucosa is an important path of exposure, but it is difficult to conduct direct dose measurement on real human subjects. In this study, we propose an in vitro method to assess the administered doses of micron-sized particles on the eyes and lips in which computed tomographic scanning and three-dimensional printing were used to create a model that includes a face, oropharynx, trachea, the first five generations of bronchi, and lung volume. This realistic model of a face and airway was exposed to monodispersed fluorescent particles released from an incoming jet. The administered dose of particles deposited upon the eyes and lips, as quantified by fluorescence intensity, was determined via a standard wiping protocol. The results show that, in this scenario, the administered doses normalized by source were 2.15%, 1.02%, 0.88%, 2.13%, and 1.55% for 0.6-, 1.0-, 2.0-, 3.0-, and 5.0-µm particles, respectively. The administered dose of large particles on the mucosa within a given exposure time has great significance. Moreover, the lips suffer a much greater risk of exposure than the eyes and account for more than 80% of total facial mucosa deposition. Our study provides a fast and economical method to assess the administered dose on the facial mucosa on an individual basis.

Integrating phylogeography and high-resolution X-ray CT reveals five new cryptic species and multiple hybrid zones among Australian earless dragons

Cryptic lineages, comprising species complexes with deep genetic structuring across the landscape but without distinct morphological differences, impose substantial difficulties for systematists and taxonomists in determining true species diversity. Here, we present an integrative approach that combines data from phylogeography and geometric morphometric analyses of three-dimensional cranial models to revisit the uncertain taxonomy of earless dragons from southern and central Australia that at one time or another have been included under the name Tympanocryptis lineata. Our approach finds strong support for seven previously described species, and more importantly, five undescribed Tympanocryptis taxa for which we provide a taxonomic treatment. We also find evidence of introgression and hybridization in three discrete contact zones between lineages, supported by mitochondrial and nuclear genes, as well as morphological analyses. With a sampling design that includes at least five individuals for each genetic lineage with corresponding X-ray microcomputed tomography scans, we perform comparative evolutionary analyses to show that there is a significant phylogenetic signal in Tympanocryptis cranial shape. Our results demonstrate the importance of using multiple specimens in each genetic lineage, particularly in cases of potential hybridization, and that geometric morphometrics, when used in an integrative framework, is a powerful tool in species delimitation across cryptic lineages. Our results lay the groundwork for future evolutionary studies in this widespread group across multiple environmental types and identify several species of immediate conservation concern with a focus on T. petersi sp. nov. We suggest that this species has undergone significant population declines and warrants a full conservation assessment.

Morphological and histological characterization of an ectopically mineralized structure in a gilthead sea bream Sparus aurata with opercular deformation

In this study, we describe an abnormal ectopically mineralized structure (EMS) that was found inside the skull of a juvenile Sparus aurata that also showed a bilateral opercular deformation. The overall phenotype and tissue composition were studied using micro-CT scanning and histological analyses. The ectopic structure occupies a large volume of the brain cavity, partially extruding into the gill cavity. It shows a dense mineralization and an extracellular matrix-rich phenotype, with variation in both the morphology and size of the cell lacunae, combined with an irregular fibre organization inside the matrix. This study is the first to report such an EMS in a juvenile teleost fish, where the tissue does not resemble any other connective tissue type described in bony fish so far. The tissue phenotype seems to rule out that the EMS corresponds to a tumorous cartilage. Yet, it is rather reminiscent of a highly mineralized structure found in cartilaginous fish, where it is suggested to be associated with damage repair.

Effect of Freeze-Thaw Cycles on Triaxial Strength Property Damage to Cement Improved Aeolian Sand (CIAS)

Natural aeolian sand has the characteristics of low cohesion and poor water stability. In order to improve its crack resistance properties in the process of freeze-thaw cycles, P.O 42.5 ordinary Portland cement was added to form a mixture called cement improved aeolian sand (CIAS). SEM was used to analyze the microscopic micro-structure of CIAS at different times (7 days and 28 days). The mechanical properties of CIAS samples affected by freeze-thaw cycles were tested in a triaxial instrument, and gray-scale images of the three-phase distribution in the CIAS after freeze-thaw cycling were obtained by computed tomography (CT) scanning technology. The pore characteristic parameters (pore area, fractal dimension, and crack length) were studied by digital image process technique. Based on classical Griffith fracture theory, the development of the crack length and crack width with increasing freeze-thaw cycles is determined. Assuming that the pore area subordinates to the Weibull distribution, the parameters of the Weibull distribution, the damage evolution defined by the elastic modulus attenuation, and the pore area development of CIAS were determined. Research shows the cohesion decreases and internal friction angle increases with increasing cycle numbers. Three development patterns are observed: crack growth, crack closure, and crack merging, and the three patterns interact during freeze-thaw cycling. Furthermore, the fractal dimension of the pore edge fluctuates with the increasing number of freeze-thaw cycles. This work provides a theoretical basis for the application of aeolian sand and develops a method for disaster prevention in applications of freeze-thaw cycling.

Differences between computed tomoghaphy and surgical findings in acute complicated diverticulitis

BACKGROUND/OBJECTIVE

A preoperative reliable classification system between clinical and computed tomography (CT) findings to better plan surgery in acute complicated diverticulitis (ACD) is lacking. We studied the inter-observer agreement of CT scan data and their concordance with the preoperative clinical findings and the adherence with the intraoperative status using a new classification of diverticular disease (CDD).

METHODS

152 patients operated on for acute complicated diverticulitis (ACD) were retrospectively enrolled. All patients were studied with CT scan within 24 h before surgery and CT images were blinded reanalyzed by 2 couples of radiologists (A/B). Kappa value evaluated the inter-observer agreement between radiologists and the concordance between CDD, preoperative clinical findings and findings at operation. Univariate and multivariate analysis were used to evaluate the predicting values of CT classification and CDD stage at surgery on postoperative outcomes.

RESULTS

Overall inter-observer agreement for the CDD was high, with a kappa value of 0.905 (95% CI = 0.850-0.960) for observers A and B, while the concordance between radiological and surgical findings was weak (kappa values = 0.213 and 0,248, respectively and 95% CI = 0.106 to 0.319 and 95% CI = 0.142 to 0.355, respectively). When overall morbidity, mortality and the need of a terminal colostomy were considered as main endpoints no concordance was observed between surgical and radiological findings and the CDD (P=NS).

CONCLUSIONS

The need for a more accurate classification of ACD, able to better stage this emergency, and to provide surgeons with reliable information for the best treatment is advocated.

The Effect of UV Irradiation on the Chemical Structure, Mechanical and Self-Healing Properties of Asphalt Mixture

Although huge numbers of investigations have been conducted for the ultraviolet (UV) aging of asphalt binder, research rarely focuses on the asphalt mixture. In order to evaluate the aging effect of UV radiation on the asphalt mixture, a dense grade of asphalt mixture was designated and aged by UV radiation for 7, 14 and 28 days respectively. After that, the chemical functional groups of asphalt binder were tested by Fourier transform infrared spectrometer (FTIR). The semi-circular bending strength and fatigue resistance of asphalt concrete were tested to characterize the mechanical properties of the asphalt concrete. To evaluate the self-healing effect of the macro-structure continuity of asphalt concrete intuitively, the computed tomography (CT) scanning machine was used to characterize the crack size of asphalt concrete samples both before and after self-healing. The results show that, with the increase of UV irradiation time, the relative ratios of the C=O and S=O bands’ areas of recovered asphalt binder increase significantly. UV radiation can significantly weaken the mechanical and self-healing properties of asphalt mixture, making the asphalt mixture to have worse macro-structure continuity, lower failure strength and worse fatigue resistance. Moreover, the longer the UV irradiation time is, the degradation effect of UV radiation on asphalt mixture becomes more obvious.

Delayed splenic hemorrhage: Myth or mystery? A Western Trauma Association multicenter study

BACKGROUND

Multi-detector computed tomography imaging is now the reference standard for identifying solid organ injuries, with a high sensitivity and specificity. However, delayed splenic hemorrhage (DSH), defined as no identified injury to the spleen on the index scan but delayed bleeding from a splenic injury, has been reported. We hypothesized that the occurrence of DSH would be minimized by utilization of modern imaging techniques.

METHODS

Data was retrospectively collected from 2006 to 2016 in 12 adult Level I and II trauma centers. All patients had an initial CT scan demonstrating no splenic injury but subsequently were diagnosed with splenic bleeding. Demographic, injury characteristics, imaging parameters and results, interventions and outcomes were collected.

RESULTS

Of 6867 patients with splenic injuries, 32 cases (0.4%) of blunt splenic hemorrage were identified. Patients were primarily male, had blunt trauma, severely injured (ISS 32 (9-57) and with associated injuries. Injuries of all grades were identified up to 16 days following admission. Overall, half of patients required splenectomy. All index images were obtained using multi-detector CT (16-320 slice). Secondary review of imaging by two trauma radiologists judged 72% (n = 23) of scans as suboptimal. This was due to poor scan quality primary from artifact(23), single phase contrast imaging (16), and/or poor contrast bolus timing or volume (6). Notably, only 28% of scans in patients with DSH were performed with optimal scanning techniques.

CONCLUSION

This is the largest reported series of DSH in the era of modern imaging. Although the incidence of DSH is low, it still occurs despite the use of multi-detector imaging and when present, is associated with a high rate of splenectomy. Most cases of DSH can be attributed to missed diagnosis from suboptimal index imaging and ultimately be avoided.

Cranial and endocranial diversity in extant and fossil atelids (Platyrrhini: Atelidae): A geometric morphometric study

OBJECTIVES

Platyrrhines constitute a diverse clade, with the modern Atelidae exhibiting the most variation in cranial and endocast morphology. The processes responsible for this diversification are not well understood. Here, we present a geometric morphometric study describing variation in cranial and endocranial shape of 14 species of Alouatta, Ateles, Brachyteles, and Lagothrix and two extinct taxa, Cartelles and Caipora.

METHODS

We examined cranial and endocranial shape variation among species using images reconstructed from CT scans and geometric morphometric techniques based on three-dimensional landmarks and semilandmarks. Principal components analyses were used to explore variation, including the Procrustes shape coordinates, summing the logarithm of the Centroid Size, the common allometric component, and residual shape components.

RESULTS

Differences in endocranial shape are related to a relative increase or decrease in the volume of the neocortex region with respect to brainstem and cerebellum regions. The relative position of the brainstem varies from a posterior position in Alouatta to a more ventral position in Ateles. The shape of both the cranium and endocast of Caipora is within the observed variation of Brachyteles. Cartelles occupies the most differentiated position relative to the extant taxa, especially in regards to its endocranial shape.

CONCLUSIONS

The pattern of variation in the extant species in endocranial shape is similar to the variation observed in previous cranial studies, with Alouatta as an outlier. The similarities between Caipora and Brachyteles were unexpected and intriguing given the frugivorous adaptations inferred from the fossil's dentition. Our study shows the importance of considering both extant and fossil species when studying diversification of complex traits.

A zero coronary artery calcium score in patients with stable chest pain is associated with a good prognosis, despite risk of non-calcified plaques

Objectives

To estimate the prevalence of non-calcified coronary artery disease (CAD) in patients with suspected stable angina and a zero coronary artery calcification (CAC) score, and to assess the prognostic significance of a zero CAC in these symptomatic patients.

Methods

In this prospective cohort study, consecutive patients with stable chest pain underwent CAC scoring ± CT coronary angiography (CTCA) as part of routine clinical care at a single tertiary centre over 7 years. Major adverse cardiac event (MACE) was defined as cardiac death, non-fatal myocardial infarction and/or non-elective revascularisation.

Results

A total of 915 of 1753 (52.2%) patients (mean age 56.8 ± 12.0 years; 46.2% male) had a zero CAC score. Of the 751 (82.1%) patients with a zero CAC in whom CTCA was performed, 674 (89.7%) had normal coronary arteries, 63 (8.4%) had non-calcified CAD with < 50% stenosis and 14 (1.9%) had ≥ 50% stenosis in at least one coronary artery. The negative predictive value of a zero CAC for excluding a ≥ 50% CTCA stenosis was 98.1%. Over a median follow-up period of 2.2 years (range 1.0-7.0 years), the absolute annualised rates of MACE were as follows: zero CAC 1.9 per 1000 person-years and non-zero CAC 7.4 per 1000 person-years (HR 3.8, p = 0.009). However, after adjusting for age, gender and cardiovascular risk factors using a multivariable Cox proportional hazards model, there was no statistically significant difference in the risk of MACE between the two patient cohorts (p = 0.19). After adjusting for age, gender and cardiovascular risk factors, the HR for all-cause mortality among the zero CAC cohort vers non-zero CAC was 2.1 (p = 0.27).

Conclusion

A zero CAC score in patients undergoing CT scanning for suspected stable angina has a high negative predictive value for the exclusion of obstructive CAD and is associated with a good medium-term prognosis.

Utility and effectiveness of the Scandinavian guidelines to exclude computerized tomography scanning in mild traumatic brain injury - a prospective cohort study

Background

In 2013 the Scandinavian Neurotrauma Committee (SNC) published updated guidelines for the initial management of minimal, mild and moderate traumatic head injuries (MTHI) that included serum analysis of protein S100B as a marker for brain tissue damage. This study reviews the effectiveness of the new guidelines in a clinical setting.

Methods

For all patients admitted to Akershus University Hospital (AHUS) from June 30th 2014 to December 15th 2014 with MTHI a separate form was filled in recording the time, indication and result of any S100B sampling and/or head computer tomography (CT) examinations. Data from these forms were compared to information derived from the electronic patient records for patients with MTHI and related diagnoses and data from the laboratory for all patients that had undergone the S100B analysis within the same period.

Results

Five hundred seventy-five patients were identified with MTHI, S100B sampling was indicated for 223 (38.8%) patients and carried out for 188 (84.3%) of these patients. 69 (36.7%) of the patients had a negative S100B test, but a head CT scan was still performed in 31 cases despite the negative S100B test. In total the guidelines were followed for 362 of 575 patients (63.0%). 180 (31.3%) of the MTHI cases were discharged without further observation or CT examinations, including 38 (21.1%) as a direct result of S100B testing. No re-admissions or missed initial traumatic brain injuries were observed.

Conclusion

The implementation of the updated SNC guidelines resulted in direct discharge of more than one third of the MTHI cases without further observation or CT examinations. One in five of these discharges was a direct result of S100B testing. However, compliance to the guidelines were poor and the guidelines were only followed in 40%. While this study showed benefits of implementing SNC guidelines to reduce the number of CT scans, additional training is needed for optimal use.