Method to Identify Accessory Root Canals using a New CBCT Software

This study describes a methodology to identify accessory root canals using the e-Vol DX software in CBCT scans. Accessory root canals are strategic shelters for microorganisms present in root canal infections. The identification of these small canals in periapical radiographic exams has limitations, besides being markedly limited accessibility to the action of endodontic instruments and to the antimicrobial agents. A significant number of accessory canals have sufficient diameters to be visible on cone-beam computed tomography (CBCT) images of high spatial resolution. Therefore, it may go unnoticed or even confused when there is no specific training for this type of diagnosis. The methodology consists in establishing thin slices (0.1mm or smaller) obtained from coronal, sagittal and axial slices. The method consists of the following steps: during navigation along the long axis of a root canal when finding a possible hypodense line of main root canal in a tomographic section (axial, sagittal or coronal), the navigation software lines of the multiplanar reconstruction (MPR) must be adjusted so that they are parallel and perpendicular to the hypodense line (parallax correction). Then, after judiciously adjusted, the accessory canal image will invariably appear as a line on one of the MPR tomographic slices, another line on another slice, and a dot on the third slice. The three sections of the MPR present images with the “line-line-dot” sequence. In this way, it is possible to identify an accessory root canal and also visualize it in volumetric reconstruction in a specific filter. The application of this method is easy to employed and may benefit the diagnosis when you want to visualize accessory root canals and distinguish it from root fracture line.

Normal decoding of the structure of the chest in the light of possibilities a new generation of high-frequency ultrasonographic sensors

Over the years of the existence of echography in Japan and the English-speaking countries, a large number of atlases and a manual textbookы where the authors describe the echo anatomy of the mammary glands have been published. The rapid technological growth has led to the fact that the echo anatomy of the mammary glands described on the basis of equipment from the 80s-90s does not correspond to the capabilities of modern ultrasonic devices. There was a need to clarify and detail the echographic image of the mammary glands, taking into account the possibilities of a new generation of 10–12 MHz high-frequency, and also upon the use of the new Doppler techniques. The anatomical structures of the mammary glands are clearly differentiated using modern ultrasound equipment. The breast tissue is normally varied widely and depends on the ratio of fat, connective and glandular tissue. The USM allows visualizing the tomographic section of the image of a fragment of the mammary gland from the skin cover to the chest wall. Key words: breast glande, ultrasonography, dopрlerography, US-sensor.

GEOPHYSICAL CHARACTERIZATION OF AQUIFERS IN THE SALITRE RIVER BASIN, BAHIA STATE, BRAZIL, USING RESISTIVITY SOUNDINGS AND ELECTRICAL TOMOGRAPHIES

ABSTRACT. The Salitre River basin, which is located in the semi-arid land of northeastern Brazil, is annually faced with severe surface-water scarcity. Twomain aquifersystems, which are distributed in depth, can be exploited to supply the water needs of the population and its present agro-industrial development: (i) a fractured-karst,water-table component, totally developed within the upper carbonate sequence of the Salitre Formation; and (ii) a fractured-clastic, semi-confined component, mostlikely associating lower Salitre limestones with the meta-sandstones of the Morro do Chap´eu Formation. Geophysical efforts have been useful in developing a regional,three-dimensional characterization of these two aquifer components of the Salitre river aquifer system and in detailing a useful electric tomographic scheme to implementtheir exploration. The geophysical survey, which comprised 64 Schlumberger electrical soundings of resistivity and five tomographic sections, was combined with welldata to define the geometric and hydraulic characteristics of these aquifer components. The inversion of the resistivity data, under the control of the well data, was usefulto reduce electrical ambiguities and to better define the depth of the water table and that of the thick, impervious aquifer substrate. The lateral and depth boundaries of thefracture-karst aquifer zones were outlined, allowing the estimation of a total reserve of approximately 100 billion m3 of groundwater. Chemical analysis of water samplescollected at production wells was used to define a water quality zoning within the basin. These results are very important to define an optimum exploration regime for thegroundwater available in the basin.Keywords: electrical sounding, tomographic section, Salitre aquifer system. RESUMO. A bacia hidrogáafica do rio Salitre faz parte da região semiárida da Bahia e, por isso, apresenta severa escassez de água superficial. Dois principais componentes aquíferos, distribuídos em profundidade, podem ser explorados para suprir as necessidades hídricas da população humana e de seu incipiente desenvolvimento agroindustrial: (i) um componente cárstico-fraturado, de natureza livre, desenvolvido nas rochas carbonáticas superiores da Formação Salitre; e (ii) um componentefraturado, semi-confinado, combinando rocha basais da sequência Salitre e unidades meta-quartzíticas da Formação Morro do Chapéu. Foram executadas 64 sondagens elétricas verticais usando o arranjo Schlumberger de eletrodos, centradas em pontos selecionados da bacia, e cinco seções tomográficas de resistividade, para detalhara estrutura subsuperficial de locais selecionados. A inversão dos dados de resistividade aparente, com controle de informações de poços, foi útil para reduzir ambiguidades elétricas e melhor definir as profundidades do nível estático e do topo do espesso substrato impermeável do sistema aquífero Salitre. Esses estudos permitiramavaliar, regionalmente, os recursos hídricos subterrâneos da bacia, em termos de geometria e características hidráulicas, bem como propor um procedimento para efetuar tomografia elétrica bidimensional, visando sua efetiva exploração por meio de poços. Os limites laterais e em profundidade das zonas de maior carstificação e de densos fraturamentos foram delineados, possibilitando estimar uma reserva total de água no sistema do rio Salitre em cerca de 220 bilhões de m3. Análises físico-químicas deamostras de água coletadas em poços foram usadas para caracterizar a variabilidade na qualidade da água subterrânea na bacia. Tais resultados podem ser usados paraplanejar um regime de exploração eficiente e conservativo das reservas de água subterrânea disponíveis.Palavras-chave: sondagem elétrica, seção tomográfica, sistema aquífero Salitre.

Long-Term Follow-Up of the Postoperative Macular Fold following the Vitreoretinal Surgery with Air Tamponade

A 64-year-old male who had a macula-on superior bullous retinal detachment in OD underwent scleral buckling, 20-gauge-pars plana vitrectomy, internal drainage of subretinal fluid with perfluorocarbon fluid, 360° endolaser and perflourocarbon-fluid-air exchange surgery. Patient sat upright immediately after the surgery for the night. At the first postoperative morning although the retina was attached, there was a macular fold extending toward the temporal retinal periphery. Patient denied further surgery. During the follow-up, retinal fold gradually became less visible and it could be noticeable only by fundus autoflorescence imaging at the sixth postoperative year with a subtle epiretinal membrane formation on the optical coherence tomographic section.

Seismic Investigation in the Bertioga Coastal Plain, Brazil

This paper presents results of seismic data from shallow seismic reflection onshore acquisition in the coastal plain of Bertioga (São Paulo State, Brazil) in order to support studies of its geological-geomorphological evolution. By using data from a CMP survey, we sought to analyze and interpret the record of three distinct events: reflected waves, refracted waves and surface waves. From the data processing, three sections were generated: stacked section of the reflected waves, tomographic section from the inversion of travel times of refracted P waves, and S-wave velocity section obtained from the inversion of dispersion curves of surface waves. The integration provided a detailed geological section with information about important contacts of quaternary units, surface of the basement rock and a geological structure that suggests a quaternary reactivation of an inferred fault.