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The aim of this exploratory study is to analyse whether three-dimensional cinematic rendering image reconstructions offer advantages over conventional volume rendering in the visualisation of cone beam computed tomography (CBCT) and computed tomography (CT) images of the facial skeleton. This is of interest, as some information gets lost during the rendering process. This especially applies to structures in the background of the image and some surface information which can be lost. The commonly applied two-dimensional representation of CBCT or CT images in three different axes requires experience for interpretation. Cinematic rendering is a new three-dimensional post processing reconstruction technique, creating photo realistic visualisations, thus possibly enabling an easier interpretation of the images. In this study, ten investigators assessed ten separate patient cases of the orofacial skeleton. For each case, a conventional volume rendering image reconstruction and a cinematic rendering reconstruction of the same area was created. A specially designed questionnaire assessed both objective and subjective criteria of image perception. Objective criteria were assessed by predefined questions on the visual perception of anatomical image characteristics, showing the two reconstruction types of each case randomly to the investigators in two sessions. Subjective criteria were assessed via a visual analogue scale, showing both reconstructions simultaneously in a third session. The results show that cinematic rendering offers advantages especially in the evaluation of depth perception and three-dimensionality. Volume rendering shows advantages in surface sharpness. Cinematic Rendering was subjectively rated higher for almost all reconstructions. The cinematic rendering process however may cause loss of information and blurring of surfaces compared to volume rendering. With respect to the subjective impression, cinematic rendering scored better than volume rendering. The visualisation is perceived as being very close to reality. • 360° rotatable 3D reconstructions were created and compared. • Cinematic rendering shows facilitates 3D and depth perception. • Volume rendering shows advantages in surface sharpness and contrast. • Cinematic rendering is perceived as photorealistic. [ABSTRACT FROM AUTHOR]

Abstract: Background: In 2005, the European Resuscitation Council and the American Heart Association published new guidelines for Advanced Life Support. One of the points was to reduce the time without chest compressions in the first phase of cardiac arrest. Objective: We evaluated in a manikin model whether using the single-use laryngeal tube with suction option (LTS-D) instead of endotracheal intubation (ET) and bag-mask-valve ventilation (BMV) for emergency airway management could reduce the “no-flow time” (NFT). The NFT is defined as the time during resuscitation when no chest compressions take place. Methods: A randomized, prospective study was undertaken with 150 volunteers who performed management of a standardized simulated cardiac arrest in a manikin. Every participant was randomized to one of three different airway management groups (LTS-D vs. ET vs. BMV). Results: The LTS-D was inserted significantly faster than the ET tube (15 s vs. 44 s, respectively, p < 0.01). During the cardiac arrest simulation, establishing and performing ventilation took an average of 57 s with the LTS-D compared to 116 s with ET and 111 s with the BMV. Using the LTS-D significantly reduced NFT compared to ET and the BMV (125 s vs. 207 s vs. 160 s; p < 0.01). Conclusions: In our manikin study, NFT was reduced significantly when the LTS-D was used when compared to ET and BMV. The results of our manikin study suggest that for personnel not experienced in tracheal intubation, the LTS-D offers a good alternative to ET and BMV to manage the airway during resuscitation, and to avoid the failure to achieve tracheal intubation with the ET, and the failure to achieve adequate ventilation with the BMV. [Copyright &y& Elsevier]