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Clinical Applications of Photon-Counting Detector Computed Tomography
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Shuai Leng, Shengzhen Tao, Kishore Rajendran, Cynthia H. McCollough
Due to its energy discriminating capability, PCD-CT can remove the energy weighting on detected photons used in conventional EIDs and therefore improve iodine contrast as well as soft tissue contrast (18, 44). The better iodine contrast provided by PCD-CT can enable the use of higher tube potential, for example, 140 kV, for a brain CTA examination while providing comparable iodine contrast as the conventional EID system with 120 kV tube potential (53). The higher tube potential can help reducing the beam-hardening artifacts typically observed near the base of skull, cervical vertebrae, and dense calcified plaques, while maintaining the required iodine to soft tissue contrast. These beam-hardening artifacts can compromise the arterial enhancement and degrade diagnostic image quality. CT angiography also benefits from PCD's simultaneous high-resolution and multi-energy capability with a single scan, where a sharp reconstruction kernel could be used to generate high-resolution CT images for visualizing small vessels, while a quantitative kernel followed by post-processing could be used for dual-energy analysis. The spectral information available via PCD-CT can enable multi-energy applications such as iodine quantification and virtual-monoenergetic imaging (VMI), which can be used to differentiate between high attenuating tissues such as iodine and calcified plaques, and therefore provide valuable additional information complementary to the conventional CT images.
Forensic Radiology
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
Claire Robinson, Bruno Morgan, Guy N. Rutty
PMCT, without any body preparation or contrast enhancement, is particularly useful in cases of traumatic injury and can demonstrate trauma in ways 2D imaging modalities cannot. It is now possible for PMCT to replace autopsy in some trauma cases as PMCT can be superior to autopsy in demonstrating some fractures, such as in the spine, base of skull, and face. These may be difficult for the pathologist to visualize, even having seen them on PMCT (Figure 31.5). Significant soft tissue injury, sufficient to cause or contribute to death, can also been seen. Liver laceration, splenic and cardiac rupture are generally all apparent without the use of contrast, although these lesions may not be visible if the subject has died before the laceration can bleed, such as from catastrophic injuries elsewhere. For example, major liver trauma as the cause of death is normally apparent, but liver lacerations in a subject who has hemorrhaged catastrophically from chest injuries, may be missed. The cause of death in such cases is often clearly demonstrated on PMCT and nothing of importance is learnt if an autopsy is performed.
Central nervous system
Published in David A Lisle, Imaging for Students, 2012
Other CT signs that may be seen with cranial trauma:Fractures of skull base and skull vaultScalp swellingIntracranial air (pneumocephalus) due to penetrating injury or fractures through paranasal sinuses or temporal bonesFluid levels in paranasal sinusesForeign bodies.
Numerical model proposed for a temporomandibular joint prosthesis based on the recovery of the healthy movement
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2018
Henrique Takashi Idogava, Pedro Yoshito Noritomi, Gregory Bregion Daniel
The temporomandibular joint (TMJ) is a natural structure that connects the mandible to the skull. It is a bilateral synovial articulation between the temporal bone of the skull and the condyle of the mandible. This articulation has a very particular geometry, being composed by a superior fossa rounded at the base of skull where the condyle is fitted. Between the condyle and the fossa there is a cartilaginous disc that allows the movements. Many factors cause the substitution of this joint, such as accidents involving shocks, traumas, pathologies, congenital deformities of the condyle branch, bites with hard objects (Landes et al. 2013), rheumatic arthritis (Ahmed 2015), wear on the surface of TMJ (Mehra et al. 2009; Singh and Detamore 2009), bruxism (Seaton 1979), and osteoarthritis (Lee et al. 2017). Due to these problems, many patients are submitted to the surgical procedure to install condylar prosthesis in order to relieve chronic pain (Aagaard and Thygesen 2014).
A comfort assessment of existing cervical orthoses
Published in Ergonomics, 2018
Joe Langley, Silvia Pancani, Karen Kilner, Heath Reed, Andy Stanton, Nicola Heron, Simon Judge, Avril McCarthy, Susan Baxter, Claudia Mazzà, Christopher J. McDermott
Twenty-one participants recorded the location of discomfort for each orthosis over the four hours. Those who did report location data did so for all devices for full duration. The reported locations were reviewed by observation by three members of the team. Digital images with transparent backgrounds were created for each of the raw data maps. The transparent maps were overlaid on each other to give one map showing all location data for all orthoses and for each orthosis separately. The combined location map data formed 12 specific location clusters around the neck, shoulders, jaw and base of skull. An additional location was added in analysis (site 13), creating a zero-reference point of no discomfort. The 13 locations are: 1. Posterior midline – occiput; 2. Post auricular; 3. Posterior Lateral neck; 4. Lateral neck; 5. Angle of the jaw; 6. Chin; 7. Anterior Midline – larynx; 8. Posterior lateral – scapulae; 9. Lateral clavicle; 10. Medial clavicle, 11; Anterior Midline – Sternum; 12 Posterior midline – lower cervical and 13 – no discomfort location. Posterior midline – upper thoracic. They are shown in Figure 3.
Serious injuries in the traffic accident situation: definition, importance and orientation for countermeasures based on a representative sample of in-depth-accident-cases in Germany
Published in International Journal of Crashworthiness, 2018
Dietmar Otte, Thorsten Facius, Stephan Brand
For seriously injured bicyclists there is also a high percentage of driving accidents. Additionally there is a high percentage of seriously injured bicyclists after turning-into or crossing accidents. The collision partner in most cases was a car (45.1%), followed by an object (35.8%). Collisions with trucks were only registered with approximately 10% but it has to be mentioned that especially these accidents are dangerous for the bicyclist because there is a high chance that the truck driver overlooks the bicyclists with the risk of overrunning him. The injury analysis showed many fractures at the face, base of skull and brain bleeding.