Injuries of the pelvis
Ashley W. Blom, David Warwick, Michael R. Whitehouse in Apley and Solomon’s System of Orthopaedics and Trauma, 2017
In Level 1/Major Trauma Centres, after initial resuscitation, patients are now taken early to the CT scanning unit for a full ‘trauma CT scan’. This comprises a CT scan of the head, neck, chest, abdomen and pelvis. Contrast is often also given. This is very helpful in excluding a bladder rupture or urethral injury. CT scanning provides a detailed anatomical view of the posterior structures, which are not seen well on conventional radiographs. CT scans can be reformatted to provide Judet views, multiplanar reconstructions (axial, coronal and sagittal images), and 3D reconstructions (Figure 29.11). Using CT scanning, 3D printing techniques can be used to print plastic moulds of pelvic fractures. This provides assistance in preoperative planning and plate contouring prior to fixation.
Multivariate analysis of variance (MANOVA)
Pat Dugard, John Todman, Harry Staines in Approaching Multivariate Analysis, 2010
The Contrasts button gives us SPSS Dialog Box 3.3, and we could use this to obtain contrasts between the last level of sessions (three sessions) and each of the two lower levels (one and two). This could be useful in helping to decide how many training sessions to use if the sessions factor is significant. Change the Contrast to Simple using the arrow and the Change button. Check that the Reference Category is Last. Click Continue and OK to get the analysis. Using the simple option, as here, tests each of the other levels of the chosen factor against the specified reference level (here, the last level). The Helmert option tests each level against the mean of the subsequent levels. The mirror image is difference, which tests each level against the mean of the previous levels. The repeated option tests each level against the next level.
Quality and Performance Tests for Dermal Drug Delivery Systems
Tapash K. Ghosh in Dermal Drug Delivery, 2020
The test should be performed under diffuse, uniform illumination (natural or artificial daylight) under conditions that reduce shadows and non-spectral reflectance to a minimum. For topical semisolids it is performed either by examination of the material in a clear, colorless vial held against a white background, or by examination of a small portion of the sample removed from its container and placed on a clean white sheet of paper. If more contrast is needed, a black background may be used. Liquids should be examined in a clear, colorless vial held against a white or black background. In each case, lighting conditions should be carefully controlled. Suitable apparatus is described in the section 2.9.20 of the European Pharmacopoeia (EP 2019a).
Study of Haralick’s and GLCM texture analysis on 3D medical images
Published in International Journal of Neuroscience, 2019
Bhawna Dhruv, Neetu Mittal, Megha Modi
Contrast refers to the difference between fluorescence that makes an object visible and can be calculated as the difference between brightness of one object compared to the other for different types of image [15]. Contrast is the difference in color that makes an object representable. When the real world is visually perceived, contrast is computed by the difference in the color and brightness of the object and other objects within the same field of view. The human visual system is more susceptible to contrast than absolute luminance; we can perceive the world in the same way in spite of the huge changes in illumination over the entire image. The highest contrast of an image is known as the contrast ratio [16]. The goal is to increase the contrast of an image so that the interpretability of an image increases. The contrast is a representative ratio of the type Luminance difference/Average luminance. This further indicates that a little difference can be neglected if average luminance is high, whereas this difference cannot be neglected if average luminance is low. The Equations (23) and (24) explain the same.
Contemporary practices using intravascular imaging guidance with IVUS or OCT to optimize percutaneous coronary intervention
Published in Expert Review of Cardiovascular Therapy, 2020
The debate for IVUS versus OCT will likely continue as their technology continue to improve. Advantages and disadvantages of IVUS and OCT have been extensively described here. However, high-definition IVUS is likely to gain favor as it becomes more widely available. HD IVUS has comparable resolution to OCT and allows detailed characterization of vessel anatomy with better tissue penetration. The lack of use of additional contrast can be beneficial in many scenarios. Patient at higher risk of developing contrast-induced acute kidney injury can benefit from IVUS-guided PCI due to the potential for lower contrast volume. In addition, co-registration with angiography and iFR allows precision PCI and can even further reduce contrast use. Ultra-low contrast and zero-contrast PCI techniques can become more attainable with the use of IVUS [54,55]. IVUS imaging will continue to improve as the next development down the pipeline is multimodality imaging systems.
An application of the theory of planned behaviour to understand compliance with daytime running headlights law among motorcycle riders
Published in International Journal of Injury Control and Safety Promotion, 2020
In traffic literature, visual conspicuity has been defined as the ability of a road user in captivating other users by means of physical features (Connors, 1975). For instance, colour, size, outline, and luminousness can increase contrast with the environment (Cavallo & Pinto, 2012; Gershon, Ben-Asher, & Shinar, 2012). Accordingly, motorists’ problems with noticing motorcycles on the road may be mitigated by enhancing conspicuity of these vehicles on the road. In this regard, several methods have been adopted to improve conspicuity of motorcycles such as increasing their frontal profile, in other word, width of motorcycle frontal part. Another option is improving motorcycle contrast through reflective stickers or use of retroreflective materials in motorcycle body designs. It has been further recommended to utilize bright or retroreflective colours on riders’ gears and helmets to amplify their contrast with their background environment particularly from dusk till dawn (Pai, 2011; Smither & Torrez, 2010). The last and the most important countermeasure that can effectively enhance conspicuity of motorcycles during daytime is active lighting which includes running lights, low and high-beam lights, and dipped headlight. Therefore, daytime running headlights (DRHs) seem to be the most practical way since they should be readily available as a basic part of all motorcycles (Gershon et al., 2012).
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