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Homogeneous development of temporal bone structures is explained by their ontogenic origin; tegmen tympani (TT) and superior semicircular canal (SSC) are related with the glenoid fossa at the temporomandibular joint (TMJ). Therefore, our objective was to determine a possible relationship between TT status (dehiscence or integrity) and the roof of the glenoid fossa (RGF) thickness; SSC status has also been considered. This cross-sectional descriptive study was conducted in two tertiary hospitals on 95 patients (109 ears) presenting hypoacusia, facial palsy, vertigo, tinnitus, and other single or combined symptoms, and submitted to a thin-section multidetector-row computed axial tomography (CT) scan. A significant interaction effect of TT × SSC statuses on RGF thickness was found (p = 0.049). A significant difference in RGF thickness was found only for SSC integrity status between TT integrity and TT dehiscence (p = 0.004). The TT dehiscence increased the risk for RGF dehiscence 12.047 times (p = 0.002). There is an interaction effect of the statuses of both TT and SSC on the thickness of the RGF, instead of an independent effect of the TT status. When RGF dehiscence is found, TT and SSC statuses should be assessed, to discard associated dehiscences.

While periodontal disease (PD) is the most common canine oral pathology, its prevalence varies according to diagnosis methodology, breed, and age. We intended to increase understanding of canine PD by studying dogs that are managed in a specific way: pack dogs in Spain. They received a mixed diet (home-prepared food, commercial dry food, stale bread and bones). Thirty-two conscious individuals from two packs of dogs in Northeastern Spain (30/32 crossbred hunting dogs and 2/32 Siberian Husky, 26 males and 6 females, 27.75 ± 5.807 kgs, 5.48 ± 2.818 years) received visual dental examination for assessment of absent teeth (AT), dental calculus (DC) grade, gingival recession (GR), periodontal disease (PD), tooth fracture (TF), and dental attrition (DA). DC was the most prevalent oral problem (75%), followed by TF/DA (68.75%), AT (34.37%), GR (31.25%), and, finally, PD (15.62%). Low individual affectation values were found for AT, GR, and PD (&lt, 1 tooth/individual), mean DC grade per individual was 0.06 ± 0.063, and TF and DA were found in 1.63 and 4.72 teeth/individual, respectively. Low prevalence and extent of PD was attributed to diagnosis methodology, bodyweight effect, breed, and, ultimately, diet. Individuals affected by DC remained under veterinary surveillance due to PD development.

Objective To study the anatomical correlation between the arcuate eminence and the superior semicircular canal. Material and methods A study of the height of the arcuate eminence was carried out in 295 temporal bones. In addition, 30 temporals with different heights of the arcuate eminence (10 flat, 10 prominent and 10 very prominent) were randomly selected and radiological tests were performed by computed tomography (Pöschl projection) and subsequent dissection by milling until the apex of the superior semicircular canal was found, establishing, with both methods, the anatomical relationship with the arcuate eminence. Results The arcuate eminence was classified as: smooth, when there was no relief (1.7%); flat, measured less than 1 mm (20.3%), prominent, measured between 1 and 2 mm, in (62%), and very prominent, measured above 2 mm (12.6%). The tomographic study (CT) and its subsequent dissection by bone milling showed a direct relationship between the arcuate eminence and the semicircular canal only when it was flat, while the rest of the types corresponded to the presence of pneumatized peri-labyrinthine cells and/or cancellous bone without a direct anatomical relationship with the apex of the superior semicircular canal. Conclusion The correlation between the arcuate eminence and the superior semicircular canal is direct only when it is flat (1 mm), being related to peri-labyrinthine cells and/or cancellous bone when the arcuate eminence is prominent or very prominent.

The objective of this study was to collect preliminary data about tooth resorption (TR) from cats treated at the Odontology Service (September 2016-June 2018), part of a University Veterinary Hospital in Spain, with specific emphasis on TR distribution per tooth. Diagnosis was based on visual/tactile inspection and intraoral dental radiographs. This cross-sectional study was carried out on 59 adult cats (27 females, 32 males). TR occurred in 39/59 cats (66.1%; 95% CI: 54.0%-78.2%). The median number of lesioned teeth per TR-affected animal was 3. A highly significant but weak correlation was found for age and number of TR-affected teeth per individual (Spearman´s correlation ρ = 0.381, P = .003, power = 0.853; N = 59). No TR cases were detected in incisors (0/708, 0%) but TR occurred in canines (21/236, 8.9%; 95% CI: 5.4%-12.4%), premolars (78/590, 13.2%; 95% CI: 10.5%-15.9%), and molars (33/236, 14%; 95% CI: 9.7%-18.3%). A significant age influence on TR was found. The greatest TR occurrence corresponded to 307 (21/59; 35.6%; 95% CI: 23.4%-47.8%) followed by 409 (17/59; 28.8%; 95% CI: 17.2%-40.3%), 407 (16/59; 27.1%; 95% CI: 15.7%-38.4%), and 309 (16/59; 27.1%; 95% CI: 15.7%-38.4%). These teeth would be considered as TR-sentinels in the studied population. These findings are relevant for veterinarians working in dental clinics, where the TR prevalence may be high especially in older cats.

Enhanced production of unconventional hydrocarbons in the United States has driven interest in natural gas development globally, but simultaneously raised concerns regarding water quantity and quality impacts associated with hydrocarbon extraction. We conducted a pre-development assessment of groundwater geochemistry in the critically water-restricted Karoo Basin, South Africa. Twenty-two springs and groundwater samples were analyzed for major dissolved ions, trace elements, water stable isotopes, strontium and boron isotopes, hydrocarbons and helium composition. The data revealed three end-members: a deep, saline groundwater with a sodium-chloride composition, an old, deep freshwater with a sodium-bicarbonate-chloride composition and a shallow, calcium-bicarbonate freshwater. In a few cases, we identified direct mixing of the deep saline water and shallow groundwater. Stable water isotopes indicate that the shallow groundwater was controlled by evaporation in arid conditions, while the saline waters were diluted by apparently fossil meteoric water originated under wetter climatic conditions. These geochemical and isotopic data, in combination with elevated helium levels, suggest that exogenous fluids are the source of the saline groundwater and originated from remnant seawater prior to dilution by old meteoric water combined with further modification by water-rock interactions. Samples with elevated methane concentrations (>14 ccSTP/kg) were strongly associated with the sodium-chloride water located near dolerite intrusions, which likely provide a preferential pathway for vertical migration of deeply sourced hydrocarbon-rich saline waters to the surface. This pre-drill evaluation indicates that the natural migration of methane- and salt-rich waters provides a source of geogenic contamination to shallow aquifers prior to shale gas development in the Karoo Basin.

Extensive development of horizontal drilling and hydraulic fracturing enhanced energy production but raised concerns about drinking-water quality in areas of shale-gas development. One particularly controversial case that has received significant public and scientific attention involves possible contamination of groundwater in the Trinity Aquifer in Parker County, Texas. Despite extensive work, the origin of natural gas in the Trinity Aquifer within this study area is an ongoing debate. Here, we present a comprehensive geochemical dataset collected across three sampling campaigns along with integration of previously published data. Data include major and trace ions, molecular gas compositions, compound-specific stable isotopes of hydrocarbons (δ13C-CH4, δ13C-C2H6, δ2H-CH4), dissolved inorganic carbon (δ13C-DIC), nitrogen (δ15N-N2), water (δ18O, δ2H, 3H), and noble gases (He, Ne, Ar), boron (δ11B) and strontium (87Sr/86Sr) isotopic compositions of water samples from 20 drinking-water wells from the Trinity Aquifer. The compendium of data confirms mixing between a deep, naturally occurring salt- (Cl >250 mg/L) and hydrocarbon-rich groundwater with a low-salinity, shallower, and younger groundwater. Hydrocarbon gases display strong evidence for sulfate reduction-paired oxidation, in some cases followed by secondary methanogenesis. A subset of drinking-water wells contains elevated levels of hydrocarbons and depleted atmospherically-derived gas tracers, which is consistent with the introduction of fugitive thermogenic gas. We suggest that gas originating from the intermediate-depth Strawn Group (“Strawn”) is flowing along the annulus of a Barnett Shale gas well, and is subsequently entering the shallow aquifer system. This interpretation is supported by the expansion in the number of affected drinking-water wells during our study period and the persistence of hydrocarbon levels over time. Our data suggest post-genetic secondary water quality changes occur following fugitive gas contamination, including sulfate reduction paired with hydrocarbon oxidation and secondary methanogenesis. Importantly, no evidence for upward migration of brine or natural gas associated with the Barnett Shale was identified.

Organic powders are polymers with organic origin in a powdered form. They are biocompatible, biodegradable, and possess positive biological attributes, and can form constructs with high mechanical properties due to their powder form. However, there are various constraints that limit organic powders to be solely used with current 3D printers. Many organic powders cannot be fused by heat and light exposure and not easy to dissolve by the printing ink. Moreover, binding solutions for silk and other organic powders are mostly acidic in nature which cause damage to current 3D powder printers as they use neutral or slight low pH inks. This work aims to address this problem by developing a 3D printer that enables the printing of an organic powder, silk. This paper presents the design and implementation of the first prototype of a novel organic powder printer. The printer incorporates a novel compression mechanism that enables the compression of the powder during the printing process. It also includes a non-corrosive binder supply system consisting of silicone peroxide tubing, a custom-built peristaltic pump, and a nozzle built from a 33-gauge needle. The powder management system consists of a powder canister apparatus, depositing mechanism, and a powder bed designed to be compatible with low flowability powders, such as silk powder. The implementation of each component and the whole printer is presented. Evaluating the functionality of the organic powder printer found that several silk powder scaffolds were able to be printed with a varying magnitude of control over architecture. Future work is required to further advance the printable constructs up to a standard found in commercial 3D printers. This work demonstrated that a 3D printer system can be developed to fabricate constructs solely out of an organic powder. The paper highlights the limitations of the current design and suggests future improvements.

Tooth resorption (TR, progressive destruction of hard dental tissues) varies in prevalence according to population, age, and country (29–66.1%). Our objective was twofold: describing the TR clinical presentation in Northeastern Spain, and studying 34 blood parameters to ascertain potential systemic effects associated with TR. Cases (29, presented from September 2018 to May 2019) and controls (58) were considered. Non-parametric tests were carried out to compare cases and controls for each blood parameter, those showing significant differences were chosen for multiple regression analysis (binomial logistic and hierarchical multiple regressions). In case TR was detected in 130/870 teeth (14.9%), TR stage and type were correlated (p &lt, 0.001). Increasing CREA values (p = 0.034) and decreasing BUN/CREA and ALB/GLOB values were associated with TR presence (p = 0.029 and p = 0.03, respectively). Increasing GLOB was associated with increasing severity of TR (p &lt, 0.01). Type 1 TR (highly related to inflammation and periodontal disease PD) was the most frequently observed type, the association of TR and inflammation biomarkers (ALB/GLOB, GLOB) are explained by this fact. The concomitant presence of PD and TR in old cats would cause TR association with kidney damage biomarkers (CREA, BUN/CREA). When affected by TR, special care in these aspects must be provided to cats.

Background: The study of the association between superior semicircular canal and other dehiscences in the temporal bone. Materials and methods: We have studied computed tomography of radiologically diagnosed people with superior or posterior semicircular canal dehiscences, in four health centres. In addition, we have studied one isolated human temporal bone, one skull and one cadaver head belonging to the collection of the Department of Human Anatomy and Histology of the University of Zaragoza that had dehiscence in the superior semicircular canal. Results: The most frequent association that we observed was between superior semicircular canal dehiscence and tegmen tympani dehiscence (37.33%). Three cases (two clinical cases and one isolated temporal bone) showed multiple associated dehiscences (tegmen tympani, mastoid antrum, posterior semicircular canal, internal auditory canal, glenoid cavity, tympanum bone and geniculate ganglion) associated with superior semicircular canal dehiscence Conclusions: When the superior semicircular canal dehiscence is associated to other in the petrous bone (tegmen tympani, mastoid antrum, posterior semicircular canal, internal auditory canal) could be grouped into the same syndrome called "otic capsule syndrome", since they have the same origin and common aetiology (otic capsule).

Objectives To analyse the ontogeny of the superior semicircular canal and tegmen tympani and determine if there are common embryological factors explaining both associated dehiscence. Methods We analysed 77 human embryological series aged between 6 weeks and newborn. Preparations were serially cut and stained with Masson's trichrome technique. Results The tegmental prolongation of tegmen tympani and superior semicircular canal originate from the same structure, the otic capsule, and have the same type of endochondral ossification; while the extension of the squamous prolongation of tegmen tympani runs from the temporal squama and ossification is directly of intramembranous type. The nuclei of ossification of the superior and external semicircular canals and accessory of tegmen collaborate in the ossification of the tegmental extension and by growth extend to the tegmental prolongation. This fact plus the fact that both structures share a common layer of external periosteum could explain the coexistence of lack of bone coverage in tegmen and superior semicircular canal. Conclusion The development of the semicircular canal and tegmen tympani could explain the causes of the association of both dehiscences.

Resumen Objetivos Analizar la ontogenia del canal semicircular superior y del tegmen tympani y determinar si hay factores embriologicos comunes que expliquen la dehiscencia asociada de ambos. Metodos Se han analizado 77 series embriologicas humanas de edades comprendidas entre las 6 semanas y recien nacidos. Las preparaciones estaban cortadas en serie y tenidas con la tecnica de tricromico de Martins. Resultados La prolongacion tegmentaria del tegmen tympani y el canal semicircular superior se originan de la misma estructura, la capsula otica, y poseen el mismo tipo de osificacion endocondral; mientras que la prolongacion escamosa del tegmen tympani se desarrolla desde la escama del temporal y su osificacion es de tipo directa o intramembranosa. En la osificacion de la prolongacion tegmentaria colaboran los nucleos de osificacion de los canales semicirculares superior, externo y accesorio del tegmen, los cuales por crecimiento se extienden hasta la prolongacion tegmentaria, este hecho sumado a que ambas estructuras comparten una capa comun de periostio externo podria explicar la coexistencia de falta de cobertura osea en el tegmen y en el canal. Conclusion El desarrollo del canal semicircular y tegmen tympani podrian explicar las causas de la asociacion de ambas dehiscencias.

Detecting and quantifying the possible association between tegmen tympani (TT) status and superior semicircular canal (SSC) pattern.Observational study.Study conducted in three tertiary Spanish hospitals.Nonselected consecutive patients of all ages (607 temporal bones).Thin-section multidetector row computed axial tomography (CAT scan) of the temporal bones.Thickness of SSC bone coverture adjacent to the middle fossa, and TT status as a dichotomous variable: dehiscence (TTD) or integrity (TTI).The observed SSC patterns were dehiscence (3.79%), papyraceous or thin (11.20%), normal (76.77%), thick (4.94%), and pneumatized (3.29%). The observed TT statuses were TTD (10.87%) and TTI (89.13%). TTD was associated with SSCD and papyraceous patterns, and TTI percentages were higher in normal and thick patterns (χ2 = 11.102; p = 0.001). The TTD probability was estimated as a function of SSC pattern and age by a multivariate binary logistics regression model (χ2 = 45.939; p 0.001).SSC pattern was significantly associated with TT status. Age influenced this association. The risk for TTD increased by 4.1% per each year of increasing age, did not differ significantly for normal and thick patterns, and increased 12 times and 20 times for papyraceous and SSCD patterns, respectively.

The last decade has seen a dramatic increase in domestic energy production from unconventional reservoirs. This energy boom has generated marked economic benefits, but simultaneously evoked significant concerns regarding the potential for drinking-water contamination in shallow aquifers. Presently, efforts to evaluate the environmental impacts of shale gas development in the northern Appalachian Basin (NAB), located in the northeastern US, are limited by: (1) a lack of comprehensive “pre-drill” data for groundwater composition (water and gas); (2) uncertainty in the hydrogeological factors that control the occurrence of naturally present CH4 and brines in shallow Upper Devonian (UD) aquifers; and (3) limited geochemical techniques to quantify the sources and migration of crustal fluids (specifically methane) at various time scales. To address these questions, we analyzed the noble gas, dissolved ion, and hydrocarbon gas geochemistry of 72 drinking-water wells and one natural methane seep all located ≫1 km from shale gas drill sites in the NAB. In the present study, we consciously avoided groundwater wells from areas near active or recent drilling to ensure shale gas development would not bias the results. We also intentionally targeted areas with naturally occurring CH4 to characterize the geochemical signature and geological context of gas-phase hydrocarbons in shallow aquifers of the NAB. Our data display a positive relationship between elevated [CH4], [C2H6], [Cl], and [Ba] that co-occur with high [4He]. Although four groundwater samples show mantle contributions ranging from 1.2% to 11.6%, the majority of samples have [He] ranging from solubility levels (∼45 × 10−6 cm3 STP/L) with below-detectable [CH4] and minor amounts of tritiogenic 3He in low [Cl] and [Ba] waters, up to high [4He] = 0.4 cm3 STP/L with a purely crustal helium isotopic end-member (3He/4He = ∼0.02 times the atmospheric ratio (R/Ra)) in samples with CH4 near saturation for shallow groundwater (P(CH4) = ∼1 atmosphere) and elevated [Cl] and [Ba]. These data suggest that 4He is dominated by an exogenous (i.e., migrated) crustal source for these hydrocarbon gas- and salt-rich fluids. In combination with published inorganic geochemistry (e.g., 87Sr/86Sr, Sr/Ba, Br−/Cl−), new noble gas and hydrocarbon isotopic data (e.g., 20Ne/36Ar, C2+/C1, δ13C-CH4) suggest that a hydrocarbon-rich brine likely migrated from the Marcellus Formation (via primary hydrocarbon migration) as a dual-phase fluid (gas + liquid) and was fractionated by solubility partitioning during fluid migration and emplacement into conventional UD traps (via secondary hydrocarbon migration). Based on the highly fractionated 4He/CH4 data relative to Marcellus and UD production gases, we propose an additional phase of hydrocarbon gas migration where natural gas previously emplaced in UD hydrocarbon traps actively diffuses out into and equilibrates with modern shallow groundwater (via tertiary hydrocarbon migration) following uplift, denudation, and neotectonic fracturing. These data suggest that by integrating noble gas geochemistry with hydrocarbon and dissolved ion chemistry, one can better determine the source and migration processes of natural gas in the Earth’s crust, which are two critical factors for understanding the presence of hydrocarbon gases in shallow aquifers.

There is a worldwide need for the transformation of primary healthcare to accommodate ageing, population growth, the rising burden of non-communicable diseases and technological advances. In this article, we discuss the role of preventive medicine as a medical specialty in the transformation of public healthcare systems. A paradigm is proposed within which different modes of medical practice support each other in accordance with their shared objective of disease prevention. The reinstitution of preventive medicine as a specialty, functioning in synergy with public health and incorporating other modalities of practice, will be of considerable benefit to healthcare in southern Africa.

This paper presents the development of a smartphone-controlled wireless device for cell optical density sensing in microfluidic chips. The footprint of the device is very compact relative to a classical laboratory spectrophotometer, making it a portable device. The cell optical density sensing device consists of an embedded microcontroller, optical sensing components, and a wireless transceiver performing cell optical density measurements in disposable microfluidic chips fabricated from poly(methylmethacrylate) polymers. The device is controlled by an Android application allowing for true portability and the possibility of remote or field operation of the device. The use of microfluidic chips as the sample carrier for optical density detection instead of a plastic cuvette allows users the flexibility to explore and/or conduct a variety of micro-scale chemical analysis using the device which would be difficult in a cuvette-based system. The function of the device is validated through a series of off-line and online optical density measurements using Saccharomyces cerevisae yeast cultures. The device is low cost, small enough to fit in most laboratory flow hood cabinets, and can be easily integrated into miniature bioreactor systems. Moreover, wireless communication enables the user to operate the device using smartphones or rapidly transfer the measured data to an online repository for analysis or storage.

3D printing technologies have enabled advances in biomedical research and development, including rapid fabrication of complex, customised constructs for personalised treatment of patients. However, there are still limitations with the 3D printing technologies in relation to the diversity of biomaterials, and the versatility of the printing methods to print such diverse materials. While many materials have been used for biomedical applications involving high load bearing forces, e.g. ceramics and metals, they struggle in areas of biodegradability, and supporting tissue adhesion. An alternative are natural polymers, which are currently being investigated in the biomedical industry and are generally biocompatible, biodegradable and bioactive. However, they lack optimal mechanical properties necessary for high load bearing applications. Natural polymers in a powdered form, also referred to as organic powders, can allow for much denser and higher integrity constructs compared to their more common bioink counterparts, whilst maintaining many of the desired biological attributes. However, many organic powders are either do not respond to light and degrade in heat, preventing their use in many light and thermal based 3D printing processes. Powder inkjet printing is a 3D printing technology that utilizes an alternative means of solidifying the powdered material. These include physical or chemical bonding, instead of photopolymerisation, melting or sintering via the exposure of heat or light. Nevertheless, the binders or solutions that are commonly used with organic powders are high in acidity which can damage the printer components, further limiting this materials printability. This paper investigates the current 3D printing technologies that can print with biomaterials. Several elements are investigated, including current biomedical applications, fusion technology, material limitations and useable biomaterials. In addition to the printing processes, a study on available biomaterials, in particular organic powders, is elaborately discussed. The origins of the biomaterials are explored, in addition to the acceptable 3D printers, current applications, and printable forms. The limitations found with the current available printing processes is also discussed, in relation to their compatibility with organic powders, and their required binder solutions.

Together, these studies provide insight into factors that may alter adolescent brain development and increase, decrease, or have no effect on subsequent risk for addiction in adulthood. Overall, these articles highlight the necessity of clinical studies focused on the real-world risks and consequences of adolescent substance use and abuse, combined with more controlled (and controllable) preclinical studies aimed at elucidating mechanistic factors by which adolescent drug exposure impacts neurocognitive functions, neural structure, and neuronal plasticity during development and into adulthood.

To describe the ontogeny of vertical semicircular canals using computed tomography. We have studied 39 human fetuses aged between 17 and 38 weeks of development through multi-helicoidal CT. The first signs of ossification in the semicircular canals, superior and posterior, are from 19 weeks of development, through two primary ossification centers in each canal, which will take part in the formation of the outer cover oriented towards the middle and posterior brain fossae, respectively. In this process it must be added the intervention of the common branch. Internal bone covers are formed by ossification of the fossa subarcuata in the superior semicircular canal, and from the compact center of the labyrinthine capsule into the posterior canal. The tomographic study has allowed us to demonstrate how ossification follows a variable rate, establishing a period between 21 and 26 weeks where there are completely closed canals with others still open to the brain fossae. The tomographic study of the semicircular canals has enabled us to establish a critical period in its ossification that could explain the etiology of the congenital-type dehiscence.

Oral health status was evaluated in 34 free-roaming cats that were submitted to a Trap-Neuter-Return program. Only 38.2% of individual cats showed oral disease. Periodontal disease (PD) was present in 6 cats ( 17.6%). Four cats (11.8%) showed feline gingivostomatitis, and clinical evidence of feline odontoclastic resorptive lesions was detected in only 3 animals (8.8%) by probing, but radiological studies would be necessary for reliable detection. Signs of PD occurred in 31.6% of teeth; only the less severe stages of PD were present. No retention of deciduous teeth, malocclusion, tumors, or dental fractures were found. Calicivirus was detected in 50% of the cats. The most frequent bacteria found were α-hemolytic Streptococcus (23.5%), Staphylococcus (17.6%), Neisseria (15.7%), and Pasteurella (11.8%). A significant association between age and oral disease was found (P = .001). The mean of bacterial strains/genus was higher in healthy mouths than in diseased mouths (4.5 vs. 2.1). In diseased mouths, Staphylococcus was the most frequently isolated genus (23.1%), whereas α-hemolytic Streptococcus was most prevalent in healthy mouths (33.3%). A significant association was detected between Porphyromonas and fungal isolation, with a fear concordance coefficient (κ = .334; P = .016).

Objective: The aim of this study is to determine whether sex and age influence posterior semicircular canal (PSC) thickness. Methods: This observational study was conducted in 3 tertiary hospitals. The minimal distance between the PSC and the posterior cranial fossa (PSC thickness) was estimated by thin-section multidetector row computed axial tomography (CAT) scan of the temporal bones. Nonselected consecutive patients of all ages (607 temporal bones) were considered. Results: A significant effect was only detected for sex (F = 5.418, p = 0.020); PSC thickness showed a higher mean value in women (mean difference ± SE: 0.224 ± 0.096 mm). A significant and negative r value was detected for males aged >45 years (-0.173, p = 0.026); in that group of patients, PSC thickness decreased as age increased (0.018 ± 0.008 mm/year). For females aged ≤45 years, a significant and positive r value was found (0.198, p = 0.022); in that group, PSC thickness increased as age increased (0.020 ± 0.008 mm/year). Conclusions: PSC thickness did not significantly evolve with age in young males (≤45 years) but it decreased from age 45 years onwards. On the other hand, PCS thickness increased with age in women until the age of 45 years and it did not significantly change in older females.

Dysphagia affects many people worldwide. Modifying foods to standard consistencies, and manual design and assembly of foods for the daily requirements of people with dysphagia is challenging. People with dysphagia may develop a dislike for pureed foods due to the unattractiveness of the appearance of the foods, the lack of variety in daily meals, and the diluted taste of meals. Three-dimensional (3D) food printing is emerging as a method for making foods for people with special mealtime needs. Very few efforts have been made to apply 3D food printing to improving the lives of people with special mealtime needs such as those with dysphagia. This paper presents the design and 3D printing of visually appetizing pureed foods for people with dysphagia with high consistency and repeatability. A tuna fish involving pureed tuna (protein), pureed pumpkin (fruit), and pureed beetroot (vegetable) is designed and then 3D printed. The steps involved in the design of tuna fish, preparation of purees, and printing of tuna fish are described. The obtained results are presented, and the findings of this research work are discussed.

Objective Our objective was to study the ontogeny of the superior semicircular canal in order to describe its peculiarities. Methods We analysed 76 series of human embryos aged between 32 days (6 mm) and newborns. The samples were cut serially and stained using Martin's trichrome technique. Results In semicircular canal development there were a number of peculiarities, such as: a defined chronological sequence of osteogenesis with a variable rate of ossification; the fact that each nucleus of ossification was involved in the formation of one of its covers (the upper in the superficial and the lower in the deep); the appearance of transitory dehiscence; and canal closure by means of bone with laminar pattern, with a minimum thickness of 0.1 mm. Conclusion The peculiarities in canal development could explain the origin of pathological dehiscence in the canal, whether congenital or acquired.

Resumen Objetivos Realizar un estudio sobre la ontogenesis del canal semicircular superior con el fin de describir sus peculiaridades. Metodos Para ello se han analizado 76 series embriologicas humanas de edades comprendidas entre los 32 dias (6 mm) y recien nacidos. Las preparaciones estaban cortadas en serie y tenidas con la tecnica de tricromico de Martins. Resultados En el desarrollo del canal semicircular hemos observado una serie de peculiaridades, como: secuencia cronologica definida de su osteogenesis con un ritmo de osificacion variable, cada nucleo de osificacion interviene en la formacion de una de sus cubiertas, el superior de la superficial y el inferior de la profunda; la aparicion de una dehiscencia transitoria, y el cierre del canal por hueso de tipo laminar con un grosor minimo de 0,1 mm. Conclusion Las peculiaridades en el desarrollo del canal podrian explicar las causas del origen de la dehiscencia patologica del mismo, ya sean congenitas o adquiridas.

Objectives Our objective was to determine if the existence of dehiscence in the superior or posterior semicircular canal was associated with the thinning of the bone roof in the rest of the vertical canals (superior or posterior). Methods The thickness of the superior and posterior semicircular canals contralateral to a dehiscence was studied using computerized tomography and compared statistically. Results When a superior semicircular canal had a dehiscence, the contralateral canal showed a significant mean decrease in its thickness of 0.5 mm (SD: 0.3 mm). This was not the case if the dehiscence was in the posterior semicircular canal, where the thickness of 2.1 mm remained unchanged (SD: 1.2 mm; P=.49). When a posterior semicircular canal showed dehiscence, no significant thinning was shown in the superior semicircular (1 mm; SD: 0.4) or in the posterior contralateral (1.3 mm; SD: 0.3) canals. Conclusion The existence of a dehiscence in the superior semicircular canal is associated with bone thinning in the canal on the opposite side, but not with the posterior semicircular canal. In contrast, if the dehiscence is in the posterior semicircular canal, contralateral and superior canal thickness is not modified.

Resumen Objetivos Determinar si la existencia de un canal semicircular superior o posterior dehiscente se asocia con el adelgazamiento de la cubierta osea en el resto de los canales verticales (superior o posterior). Metodos Se estudia mediante tomografia computarizada y se compara estadisticamente el espesor de los canales semicirculares superiores y posteriores contralaterales a una dehiscencia. Resultados Cuando un canal semicircular superior presentaba una dehiscencia, el canal contralateral mostraba un adelgazamiento significativo de su espesor con una media de 0,5 mm (DE: 0,3 mm). No sucede lo mismo con los posteriores que no modifican su grosor de 2,1 mm (DE: 1,2 mm; p = 0,49). Cuando un canal semicircular posterior presentaba dehiscencia no se observo adelgazamiento significativo en los canales semicirculares superiores 1 mm (DE: 0,4), ni en el posterior contralateral 1,3 mm (DE: 0,3). Conclusion La existencia de una dehiscencia del canal semicircular superior se asocia al adelgazamiento del hueso del canal del lado contrario, pero no de los canales semicirculares posteriores. No ocurre lo mismo si la dehiscencia es del canal semicircular posterior, que no altera de manera significativa el espesor del canal del lado contralateral ni en los superiores.

This study aimed to investigate the effects of a single session of sprint interval training (SIT) and a single extended sprint (ES), matched for total work, on metabolic health biomarkers.Ten overweight/obese men aged 26.9±6.2years participated. Following a pre-trial incremental exercise test and SIT familiarization, each participant undertook three 2-day trials in randomized order. On Day 1 participants either undertook no exercise (CON), four maximal 30-s sprints, with 4.5min recovery between each (SIT), or a single maximal extended sprint (ES) matched with SIT for work done. On Day 2, participants had a fasting blood sample taken, undertook an oral glucose tolerance test to determine insulin sensitivity index (ISI), and had blood pressure measured.Total work done during exercise did not differ between SIT and ES (61.7±2.9 vs. 61.3±2.8kJ; p=0.741). Mean power was higher in SIT than ES (518±21 vs. 306±16W, p0.0005), resulting in a shorter high-intensity exercise duration in SIT (120±0 vs. 198±10s, p0.0005). ISI was 44.6% higher following ES than CON (9.4±2.1 vs. 6.5±1.3; p=0.022), but did not differ significantly between SIT and CON (6.6±0.9 vs. 6.5±1.3; p=0.208). However, on the day following exercise fat oxidation in the fasted state was increased by 63% and 38%, compared to CON, in SIT and ES, respectively (p0.05 for both), with a concomitant reduction in carbohydrate oxidation (p0.05).A single ES, which may represent a more time-efficient alternative to SIT, can increase insulin sensitivity and increase fat oxidation in overweight overweight/obese sedentary men.

Background There are an estimated 11,000 transfers that occur throughout the UK per year. 1 These are costly and dangerous and result in a three day increase in length of stay for critically unwell patients. 2 Due to the centralization of services and increase of tertiary centres these transfers are becoming more common. The original didactic “Tricky Trips course”, initiated by SECCCN, required improvements based on candidate feedback. Due to significant variation in delivery and dwindling faculty numbers, the course needed modernising. There are well defined guidelines for transfer by the AAGBI and the ICS. With the development of a specialised simulation ambulance, an opportunity arose to develop a inter-professional simulation based transfer course. Description of innovation The course format involves: Pre-course reading material Introductory workshop Faculty demonstration In course MCQ paper Simulated scenario based sessions “Problems on transfer” discussion session Candidates are assigned to inter-professional groups involving doctors, ODPs and nurses. Example simulated scenarios include: Packaging of the time-critical head injury CT Scan Level 3 Intra-hospital transfer Inter-hospital transfer including simulation ambulance drive Each session concludes with a faculty facilitated debrief session on technical and human factors aspects of transfers. Outcomes Feedback has been excellent with 100% of candidates recommending this course. Feedback praise has been positive for scenario design, realism and organisation of the course. The course has attracted a HEKSS funding bid for development and is awaiting formal endorsement from the ICS. Take home messages The STricT course has developed a standardised, curriculum mapped, interprofessional, simulated transfer training course. Giving candidates hands-on transfer and road ambulance training, learning outcomes are successfully achieved, producing more confident transfer teams. Developments for the future: Expanding scenario and MCQ bank Creating demonstration videos Offering the course package to other providers Reference The Intensive Care Society (3rd Edition 2011). Guidelines for the Transport for the Critically Ill Adult 2 NW Knudsen et al . Impact of Interhospital Intensive Care Unit Transfers. Critical Care 2001; 5 (Suppl 1);173. ICS - Intensive Care Society SECCCN - South East Coast Critical Care Network AAGBI - Association of Anaesthetists of Great Britain and Ireland

To study the radiological patterns of the bony roof of the superior semicircular canal with a view for obtaining readily applicable conclusions.84 patients (163 petrous bones) have been studied by Multi-slice Helical Computed tomography (Philips Brilliance 6). We have determined the distribution of the different types of bone cover of the superior semicircular canal, taking some previously notified, standardised measurements of normality as reference.During the analysis of the roof of the superior semicircular canal, we have distinguished five different types, depending on their thickness and tomodensitometric aspect. Normal pattern in 121 cases (74.2 %), with a thickness of between 0.6 and 1.7 mm, papyraceous pattern or fine thickness ≤0.5 mm that appears in 23 of our cases (14.1 %), thick pattern ≥1.8 mm that we have observed in 11 cases (6.7 %), and pneumatised pattern in 5 cases (3.1 %), which is characterised by having supralabyerinthine cells. Finally, a dehiscent pattern was observed in three cases (1.8 %).We describe five patterns of superior semicircular canal roofs: normal, thick, papyraceous, pneumatised and dehiscent. The papyraceous type and the dehiscent type would be subject to producing pathology, and in some cases the latter could be a consequence of the former.

SUMMARY Genetically modified swine hold great promise in the fields of agriculture and medicine. Currently, these swine are being used to optimize production of quality meat, to improve our understanding of the biology of disease resistance, and to reduced waste. In the field of biomedicine, swine are anatomically and physiologically analogous to humans. Alterations of key swine genes in disease pathways provide model animals to improve our understanding of the causes and potential treatments of many human genetic disorders. The completed sequencing of the swine genome will significantly enhance the specificity of genetic modifications, and allow for more accurate representations of human disease based on syntenic genes between the two species. Improvements in both methods of gene alteration and efficiency of model animal production are key to enabling routine use of these swine models in medicine and agriculture.

Laboratory-based studies have demonstrated that adding protein (PRO) to a carbohydrate (CHO) supplement can improve thermoregulatory capacity, exercise performance and recovery. However, no study has investigated these effects in a competitive sporting context. This study assessed the effects of combined CHO-PRO supplementation on physiological responses and exercise performance during 8 days of strenuous competition in a hot environment. Twenty-eight cyclists participating in the TransAlp mountain bike race were randomly assigned to fitness-matched placebo (PLA 76 g L(-1) CHO) or CHO-PRO (18 g L(-1) PRO, 72 g L(-1) CHO) groups. Participants were given enough supplements to allow ad libitum consumption. Physiological and anthropometric variables were recorded pre- and post-exercise. Body mass decreased significantly from race stage 1 to 8 in the PLA group (-0.75 ± 0.22 kg, P = 0.01) but did not change in the CHO-PRO group (0.42 ± 0.42 kg, P = 0.35). Creatine kinase concentration and muscle soreness were substantially elevated during the race, but were not different between groups (P = 0.82, P = 0.44, respectively). Urine osmolality was significantly higher in the CHO-PRO versus the PLA group (P = 0.04) and the rise in tympanic temperature from pre- to post-exercise was significantly less in CHO-PRO versus PLA (P = 0.01). The CHO-PRO group also completed the 8 stages significantly quicker than the PLA group (2,277 ± 127 vs. 2,592 ± 68 min, respectively, P = 0.02). CHO-PRO supplementation therefore appears to prevent body mass loss, enhance thermoregulatory capacity and improve competitive exercise performance despite no effect on muscle damage.

Introduction The main purpose of this study is to determine the radiological incidence of Superior (SSCD) and Posterior Semicircular Canal Dehiscence (PSCD) and to compare radiologic SSCD to the incidence of this condition on cadaver specimen. We have also analysed the relation between the ossification state of the semicircular canals and the degree of mastoid pneumatization and integrity of Tegmen Tympani . Material and methods Temporal bones have been investigated by means of CT scan on patients and direct observation on cadaver specimen, respectively. Results 604 ears and 160 cadaver temporal bones have been investigated by means of CT scan and direct observation, respectively. 3.6% and 0.3% of the studied ears had SSCD and PSCD, respectively, on CT scan. Only 0.6% of the cadaver specimen ears did have anatomical SSCD. Degree of pneumatization of the mastoid bone is related to the mean thickness of bone overlying the Superior and Posterior Semicircular Canal. Radiological absence of Tegmen Tympani is more frequent in ears that also have radiologic SSCD. Conclusion CT scanning gives higher incidence figures of SSCD than anatomical studies, 3.6% vs. 0.6%. We also found a 0.6% incidence of radiological PSCD in the studied ears. There is a direct relation between the degree of ossification of Superior and Posterior Semicircular Canal and certain temporal bone anatomic features: temporal bone pneumatization and absence/presence of Tegmen Tympani or Antri .

e19031Background: The myeloproliferative neoplasms (MPNs) are a rare hematologic malignancy with significant symptom burden. Disease-related registries can be a useful and important tool for rare d...

Regular physical activity (endurance training, ET) has a strong positive link with cardiovascular health. The aim of this review is to draw together the current knowledge on gene expression in different cell types comprising the vessels of the circulatory system, with special emphasis on the endothelium, and how these gene products interact to influence vascular health. The effect beneficial effects of ET on the endothelium are believed to result from increased vascular shear stress during ET bouts. A number of mechanosensory mechanisms have been elucidated that may contribute to the effects of ET on vascular function, but there are questions regarding interactions among molecular pathways. For instance, increases in flow brought on by ET can reduce circulating levels of viscosity and haemostatic and inflammatory variables that may interact with increased shear stress, releasing vasoactive substances such as nitric oxide and prostacyclin, decreasing permeability to plasma lipoproteins as well as the adhesion of leucocytes. At this time the optimal rate-of-flow and rate-of-change in flow for determining whether anti-atherogenic or pro-atherogenic processes proceed remain unknown. In addition, the impact of haemodynamic variables differs with vessel size and tissue type in which arteries are located. While the hurdles to understanding the mechanism responsible for ET-induced alterations in vascular cell gene expression are significant, they in no way undermine the established benefits of regular physical activity to the cardiovascular system and to general overall health. This review summarizes current understanding of control of vascular cell gene expression by exercise and how these processes lead to improved cardiovascular health.

Purpose: Increased blood lactate concentration has been suggested as a primary stimulus for the exercise-induced growth hormone response (EIGR). Patients with McArdle disease are unable to produce lactate in response to exercise and thus offer a unique model to assess the role of lactate in the EIGR. Accordingly, McArdle’s patients were exercised to test the hypothesis that lactate is a major stimulus of the EIGR. Methods: 11 patients with McArdle disease (3 male, 8 female; age: 35.5 (SD 13.9) years, height: 166 (8) cm, body mass: 75.2 (13.1) kg) were recruited for the study. The patients walked initially at 0.42 m/s, increasing by 0.14 m/s per 3 min stage. Exercise was terminated when participants completed 3 minutes at 1.80 m/s or when a Borg CR10 pain scale rating of “4” was reached. Stages were separated by 60 s for capillary blood sampling for analysis of hGH and blood lactate concentration. Results: McArdle’s patients’ blood lactate levels remained at resting levels (0.3–1.2 mmol/l) as exercise intensity increased. Nine out of 11 participants failed to demonstrate an EIGR obtaining hGH values below the clinical definition of a response (>3 μg/l). Conclusion: The absence of an EIGR in nine out of 11 participants suggests that lactate could play a major role in the EIGR in humans.

In a recent paper we demonstrated that elephant bull groups and mixed herds exhibited spatial and resource segregation across the Kruger National Park. It was found, inter alia, that both bull groups and mixed herds occurred more frequently closer to rivers than expected if they were randomly distributed, but that only bull groups occurred more frequently closer to the artificial waterholes. Although Chamaille-Jammes et al. (2007) accepted these results, they disagreed with our interpretation regarding the potential effect that closure of artificial waterholes might have. Here we address some of the specific concerns expressed and provide a broader context regarding water provision and elephant management. Although water provision can influence elephant density and distribution, we argue that the effectiveness of surface-water manipulation as a management tool will depend on (1) natural surface-water availability, (2) forage quality, (3) elephant densities, (4) position of a population on its growth trajectory, and (5) management objectives. Even though elephants are water-dependent, the effectiveness of water provision as a management tool will therefore be area- and population-specific and will depend on management objectives.

Resumen Presentar el primer caso de sindrome de dehiscencia del canal semicular superior publicado en lengua espanola y establecer, con estudios embriologicos, el periodo embriologico implicado en la genesis del sindrome Material y metodos Se estudian 52 series embriologicas fetales, desde 6 mm hasta recien nacidos. Se presenta el caso de un paciente que presentaba un sindrome de dehiscencia de canal semicurcular superior Resultados Existe una relacion de continuidad, a traves de lagunas oseas, entre el canal semicircular superior y el espacio intracraneal en el feto de 24 a 28 semanas pero esta relacion se pierde en la semana 30. Se exponen los resultados del cierre quirurgico de la fistula, en el paciente estudiado, con un abordaje por la fosa media y con abordaje transmastoideo Conclusiones El sindrome podria ser secundario a una alteracion del desarrollo embriologico y, por tanto, su genesis seria prenatal. La reparacion quirurgica por via transmastoidea es una alternativa razonable a la via de la fosa media

Resumen Hemos estudiado el desarrollo de los osiculos timpanicos en 40 series embrio-fetales humanas de edades comprendidas entre los 32 dias (6 mm) y el nacimiento. Una vez realizadas las mediciones para datar cronologicamente los embriones y fetos, se llevo a cabo una minuciosa y cuidada diseccion de los temporales en bloque; posteriormente fueron fijados en formol al 10%, descalcificados con acido nitrico al 2%, deshidratados en alcoholes a concentraciones progresivamente crecientes, incluidos en parafina, cortados en serie a 7 mm, y tenidos en serie con la tecnica del Tricromico de Martins. Los osiculos timpanicos se desarrollan en el mesenquima de los dos primeros arcos faringeos. La cabeza del martillo, el cuerpo y la apofisis corta del yunque se originan del primer arco mientras que el mango del martillo, la apofisis larga del yunque y la masa del estribo lo hacen del segundo. La lamina vestibular de la platina se desarrolla en la capsula otica. Los osiculos timpanicos se desarrollan por osificacion endocondral con excepcion de la apofisis anterior del martillo que lo hace por osificacion membranosa. En su ontogenia se observan seis estadios. En el primero se produce la formacion de sus esbozos por condensacion del mesenquima, en el segundo "precartilaginoso" las celulas de los primordios se diferencian a condroblastos, en el tercero "cartilaginoso" los osiculos presentan una estructura cartilaginosa, en el cuarto se forman los centros de osificacion primarios, en el quinto aparecen en los osiculos el collar periostico y en su interior hueso endocondral, y en el ultimo estadio el tejido oseo se va extendiendo progresivamente hasta adquirir una estructura osea compacta.

Objective: To provide insight into discussions at the Surgeon General's Listening Session, “Toward a National Action Plan on Overweight and Obesity,” and to complement The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity. Research Methods and Procedures: On December 7 and 8, 2000, representatives from federal, state, academic, and private sectors attended the Surgeon General's Listening Session and were given an opportunity to recommend what to include in a national plan to address overweight and obesity. The public was invited to comment during a corresponding public comment period. The Surgeon General's Listening Session was also broadcast on the Internet, allowing others to view the deliberations live or access the archived files. Significant discussion points from the Listening Session have been reviewed by representatives of the federal agencies and are the basis of this complementary document. Results: Examples of issues, strategies, and barriers to change are discussed within five thematic areas: schools, health care, family and community, worksite, and media. Suggested cooperative or collaborative actions for preventing and decreasing overweight and obesity are described. An annotated list of some programmatic partnerships is included. Discussion: The Surgeon General's Listening Session provided an opportunity for representatives from family and community groups, schools, the media, the health-care environment, and worksites to become partners and to unite around the common goal of preventing and decreasing overweight and obesity. The combination of approaches from these perspectives offers a rich resource of opportunity to combat the public health epidemic of overweight and obesity.

The effects on the testis of open-ended vasectomy in the Wistar rat have been assessed morphometrically and evaluated statistically at 1, 4, 12, and 24 weeks after operation, and compared to those in sham-operated controls. The open-ended technique, ie, without ligation of the epididymal end of the cut ductus deferens, allowed drainage of sperm into the spermatic cord. During the period of our study, it did not affect the structure of the testis; although the germinal epithelium, basement membrane, and the stroma and cells of the interstitial space all showed variations when compared to the control group, these were not statistically significant. Clin. Anat. 15:335–339, 2002. © 2002 Wiley-Liss, Inc.

Resumen Se ha estudiado el desarrollo de la union entre el mango del martillo y la membrana del timpano en embriones y fetos humanos. Para ello se han utilizado 25 huesos temporales de fetos humanos, cuyas edades cronologicas van desde los 36 dias (14 mm) hasta las 29 semanas (270 mm). Las muestras fueron fijadas en formol al 10%, descalcificadas con acido nitrico al 2%, incluidas en parafina, cortadas en serie a 7 ?m, y tenidas con el metodo Tricromico de Martins. Se han identificado varias etapas en el desarrollo de la pseudoarticulacion entre el martillo y la membrana del timpano. En la primera el mango se adhiere intimamente al mesenquima de la membrana del timpano primitiva, en la segunda dicho mesenquima se hace laxo y en el aparecen capilares, en la tercera aparecen fibras de colageno de disposicion radial, y en la cuarta el ahuecamiento del tapon meatal da independencia a la membrana del timpano del conducto auditivo externo. La porcion distal del mango, incluida en la membrana del timpano, ha permanecido con una estructura cartilaginosa durante todo el tiempo estudiado. Las fibras de colageno a nivel del umbo rodean al extremo terminal del mango mientras que en el resto de el lo hacen solamente en su arista anterior.

Frey syndrome is a common complication after parotidectomy. The time from surgery to disease onset may be quite long; therefore, a time-to-event analysis was performed for the occurrence of this syndrome post-parotidectomy. Three hundred and thirty-four patients who underwent a parotidectomy between January 2002 and November 2012 were identified (retrospective study). Of these patients, 102 developed Frey syndrome post-surgery and 232 did not. The time-to-onset analysis enabled us to estimate the risk ratio associated with different types of parotid gland tumours, various parotidectomy procedures, and repeat parotidectomy, which is useful for predicting preoperative and surgical risk. The risk of developing Frey syndrome was lower in patients with malignant tumours than in those with benign tumours (risk ratio 0.351, 95% confidence interval (CI) 0.155–0.594). Risk ratios for lumpectomy PA (pre-auricular area), superficial parotidectomy, and total parotidectomy with respect to lumpectomy T (tail) were 4.378 (95% CI 1.168–16.410), 8.040 (95% CI 3.286–19.670), and 8.174 (95% CI 3.076–21.723), respectively. Repeat parotidectomy also increased the risk of developing Frey syndrome (risk ratio 3.214, 95% CI 1.547–6.678). No effect of the use of a superficial muscular aponeurotic system (SMAS) flap on the risk of developing Frey syndrome was detected (P = 0.888).

To evaluate the potential health issues associated with periodontal disease (PD) in dogs, 1004 teeth from 25 dogs were examined. The dogs were randomly selected, aged 2-14 years, and had at least 95% of their teeth at the first PD stage. Significant positive correlations between plaque grade (PG) and gum inflammation, gingival regression, periodontal pocket, age and serum alanine aminotransferase (ALT) activity were identified. In contrast, PG was negatively correlated to total platelet count. Altogether, these findings suggest that prevention and therapy at the first PD stages can have an important impact on the general health condition of dogs.

The identification and definition of the radiological patterns of the posterior semicircular canal (PSC), with a view to obtain readily applicable conclusions. The parietal morphology of the PSC has been studied by multi-slice helical computed tomography (Philips Brilliance 6). We have determined the distribution of the different types of bone cover of the PSC, taking some previously notified, standardised measurements of normality as reference. 318 patients have been analysed (604 petrous bone) by CT and we have distinguished five different radiological patterns: type or normal, thick, thin, pneumatised and dehiscent. The first three patterns, normal, thick and thin, have in common the existence of a compact bone interposed between PSC and posterior fossa, being in the normal pattern has a thickness of between 0.9 and 2.5 mm (327 cases, 54.13 %), in the thick pattern is ≥2.6 mm (99 cases, 16.39 %) and in the thin pattern is ≤1.2 mm (158 cases, 26.15 %). The fourth pattern, pneumatised, is characterised by having retro labyrinthine cells between PSC and media fossa (19 cases, 3.14 %). Finally, a dehiscent pattern was observed in 2 cases (0.3 %). We describe five different radiological patterns: type or normal, thick, thin, pneumatised and dehiscent. The thin type (

HYPOTHESIS Posterior semicircular canal dehiscence (PSCD) may be of congenital origin. BACKGROUND PSCD is characterized by the lack of bone coverage, which results in its lumen being exposed to the meninges of the posterior cranial fossa or to the gulf of the jugular vein. It has an incidence of 0.2%. Its presence has been associated with several well-defined entities, although a congenital origin has not been proven. METHODS We have analyzed, from a macroscopic, microscopic, and radiologic (computed tomography) viewpoint, the right temporal bone of a 32-week-old human fetus that presented a defect in the bone coverage located in the rear. RESULTS The macroscopic study showed a solution of continuity in the posterior semicircular canal, with elliptic morphology and smooth edges. This defect was 3.4 mm long with a width that varied between 0.67 mm in its apical portion and 1.42 in the basal portion. The radiologic study (computed tomography) showed the absence of bone coverage of the posterior semicircular canal, which was open to the intracranial space in the posterior fossa. Its histologic study showed good bone coverage of this canal at the expense of compact bone tissue. However, at the medial end, there is a lack of bone coverage, resulting in the lumen of the canal being open to the intracranial space. The bone edges of the defect did not present any osteoclast activity. CONCLUSION The lack of bone coverage (dehiscence) of the posterior semicircular canal in a 32-week-old fetus suggests a congenital component of bony dehiscences of this canal. Even so, this single finding does not conclusively prove the congenital component, and the dehiscence is a finding that can be part of and not by itself a syndrome.

Determine if aging and menopause, known to be associated with bone resortion, also are associated with superior semicircular canal dehiscence.Observational study.Study conducted in 3 tertiary Spanish hospitals.Nonselected consecutive patients of all ages.Thin-section multi-detector row computed tomographic scan of the temporal bones.The minimum thickness of the bone covering the roof of the superior semicircular canal (SSC) measured in each temporal bone. The outcome was studied both as a continuous and as a dichotomous variable: thin (0.6 mm) and normal (≥ 0.6 mm).Five hundred eighty-two ears of 312 patients were included in the study. Fifty-five percent of the sample were women. Patient's age ranged from 2 to 88 years. A 40-year age difference between ears was associated with a decreased thickness of bone covering the SSC of 0.10 mm, which is 10% of the average thickness of such bone. The thickness of the bone overlying the SSC of subjects younger than 45 years was an average of 1.14 mm (SD, 0.52 mm), whereas that of the subjects older than 45 years was equal to 1.02 mm (SD, 0.45 mm; p = 0.006). The percentage of ears with thin bone coverage of SSC was 7.1% in subjects younger than 45 years and 13.8% in those older than 45 years (p = 0.013).Our data support the hypothesis that there is a slight osteopenia of the roof of the superior semicircular canal associated with aging, and this effect seems to be more pronounced in menopausal women.