• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권5호
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• pp.356-360
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• 2017

The tympanic plate is a small part of the temporal bone that separates the mandibular condyle from the external auditory canal. Fracture of this small plate is rare and usually associated with other bony fractures, mainly temporal and mandibular bone. There is a limited amount of literature on this subject, which increases the chance of cases being overlooked by physicians and radiologists. This is further supported by purely isolated cases of tympanic plate fracture without evidence of other bony fractures. Cone-beam computed tomography is an investigative three-dimensional imaging modality that can be used to detect fine structures and fractures in maxillofacial trauma. This article presents four cases of isolated tympanic plate fracture diagnosed by cone-beam computed tomography with no evidence of fracture involving other bones and review of the literature.

• 대한방사선기술학회지:방사선기술과학
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• 제34권3호
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• pp.215-219
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• 2011

양성자 치료에서 X선 영상정보가 직접적인 양성자의 저지능 정보를 제공할 수 없는 한계로 인한 자료의 오류를 피하기 위해, 양성자 빔을 이용한 전산화단층촬영 영상의 사용을 위한 전산모사 연구를 시행하고, 적절한 하드웨어 구성과 그 가능성을 연구하였다. GEANT4를 사용한 전산모사에서 두 개의 DSSD를 사용하여 입사되는 양성자 빔의 위치정보를 획득하고 LYSO 섬광검출기로 에너지를 측정하여 획득한 양성자 영상을 단층촬영 영상으로 재구성하여 사용할 수 있음을 확인하였다.

• Journal of Korean Neurosurgical Society
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• 제55권6호
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• pp.357-361
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• 2014

Computed tomography angiography (CTA) is commonly used in setting of subarachnoid hemorrhage, but imaging features of aneurysm rupturing taking place at the time of scanning has rarely been described. The author reports a case of actively rebleeding aneurysm of the anterior communicating artery with intraventricular extravasation on the hyperacute CTA imaging. The rebleeding route, not into the third ventricle but into the lateral ventricles, can be visualized by real-time three-dimensional CT pictures. The hemorrhage broke the septum pellucidum and the lamina rostralis rather than the lamina terminalis.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.501-504
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• 2003

The purpose of this work is to introduce some fundamental stereological concepts to quantify damage parameters using X-ray CT(Computed Tomography) in the scope of CDM(Continuum Damage Mechanics). X-ray CT is a completely nondestructive technique for visualizing features in the interior of opaque solid objects, and for obtaining digital information on their 3D geometries and properties. Many researchers have introduced lots of damage parameters to model the mechanical behavior of deteriorated materials. Those damage parameters can be represented in many forms such as specific void or crack surfaces, the spacing between cracks, the specific damaged surface area, the specific damaged surface area tensor, the mean solid path among the damaged surfaces and the mean solid path tensor. Despite of many accomplishments in CDM since there is no the systematic experiment, it have limitations in application. In this situation, X-ray computed tomography is highlited by many researchers and applied in a wide range of materials including rock, bone, ceramic, metal, soft tissue and concrete.

• Imaging Science in Dentistry
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• 제36권3호
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• pp.123-129
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• 2006

The use of computed tomography for dental procedures has increased recently. Cone beam computed tomography (CBCT) systems have been designed for imaging hard tissues of the dentomaxillofacial region. CBCT is capable of providing high resolution in images of high diagnostic quality. This technology allows for 3-dimensional representation of the dentomaxillofacial skeleton with minimal distortion, but at lower equipment cost, simpler image acquisition and lower patient dose. Because this technology produces images with isotropic sub-millimeter spatial resolution, it is ideally suited for dedicated dentomaxillofacial imaging. In this paper, we provide a brief overview of cone beam scanning technology and compare it with the fan beam scanning used in conventional CT and the basic principles of currently available CBCT systems.

• Imaging Science in Dentistry
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• 제46권1호
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• pp.47-51
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• 2016

Herein, we report and discuss the detection of fossa navicularis magna, a close radiographic anatomic variant of canalis basilaris medianus of the basiocciput, as an incidental finding in cone-beam computed tomography (CBCT) imaging. The CBCT data of the patients in question were referred for the evaluation of implant sites and to rule out pathology in the maxilla and mandible. CBCT analysis showed osseous, notch-like defects on the inferior aspect of the clivus in all four cases. The appearance of fossa navicularis magna varied among the cases. In some, it was completely within the basiocciput and mimicked a small rounded, corticated, lytic defect, whereas it appeared as a notch in others. Fossa navicularis magna is an anatomical variant that occurs on the inferior aspect of the clivus. The pertinent literature on the anatomical variations occurring in this region was reviewed.

• Imaging Science in Dentistry
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• 제49권3호
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• pp.179-190
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• 2019

Panoramic radiographs and computed tomography (CT) play a paramount role in the accurate diagnosis, treatment planning, and prognostic evaluation of various complex dental pathologies. The advent of cone-beam computed tomography (CBCT) has revolutionized the practice of dentistry, and this technique is now considered the gold standard for imaging the oral and maxillofacial area due to its numerous advantages, including reductions in exposure time, radiation dose, and cost in comparison to other imaging modalities. This review highlights the broad use of CBCT in the dentomaxillofacial region, and also focuses on future software advancements that can further optimize CBCT imaging.

• Journal of Radiation Protection and Research
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• 제46권4호
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• pp.151-159
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• 2021

Background: Computed tomography (CT) is one of the crucial diagnostic tools in modern medicine. However, careful monitoring of radiation dose for CT patients is essential since the procedure involves ionizing radiation, a known carcinogen. Materials and Methods: The most desirable CT dose descriptor for risk analysis is the organ absorbed dose. A variety of CT organ dose calculators currently available were reviewed in this article. Results and Discussion: Key common elements included in CT dose calculators were discussed and compared, such as computational human phantoms, CT scanner models, organ dose database, effective dose calculation methods, tube current modulation modeling, and user interface platforms. Conclusion: It is envisioned that more research needs to be conducted to more accurately map CT coverage on computational human phantoms, to automatically segment organs and tissues for patient-specific dose calculations, and to accurately estimate radiation dose in the cone beam computed tomography process during image-guided radiation therapy.

• 한국임상수의학회지
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• 제24권4호
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• pp.667-672
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• 2007

This report describes the use of conventional computed tomography(CT) for the diagnosis of head trauma in three canine patients. According to physical and neurologic examinations, survey radiography and computed tomography, these patients were diagnosed as traumatic brain injury. Especially, CT is the imaging modality of first choice for head trauma patients. It provides rapid acquisition of images, superior bone detail, and better visualization of acute hemorrhage than magnetic resonance imaging. It is also less expensive and more readily available. Pre-contrast computed tomography was used to image the head. Then, post-contrast CT was performed using the same technique. The Modified Glasgow Coma Scale(MGCS) score was used to predict their probability of survival rate after head trauma in these dogs. Computed tomogram showed fluid filled tympanic bulla, fracture of the left temporal bone and cerebral parenchymal hemorrhage with post contrast ring enhancement. However, in one case, computed tomographic examination didn't delineate cerebellar parenchymal hemorrhage, which was found at postmortem examination. Treatments for patients placed in intensive care were focused to maintain cerebral perfusion pressure and to normalize intracranial pressure. In these cases, diagnostic computed tomography was a useful procedure. It revealed accurate location of the hemorrhage lesion.

• Imaging Science in Dentistry
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• 제50권4호
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• pp.365-371
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• 2020

While silent sinus syndrome (SSS) is familiar to otolaryngologists and ophthalmologists, it is a rare clinical entity in dentistry and is likely to be underdiagnosed due to dentists' lack of awareness of this condition. SSS presents a diagnostic challenge to dentists, as patients typically have no history of trauma or sinusitis. The characteristic feature of SSS is a gradual retreat of the maxillary sinus walls, resulting in enophthalmos and hypoglobus. Multidetector (multislice) computed tomography is the imaging modality of choice for SSS and other paranasal sinus diseases. Cone-beam computed tomography promises to be an alternative low-dose imaging modality. This report describes 3 cases of SSS in adults, who had no identified clinical symptoms except diminutive and opacified maxillary sinuses, as well as the inward bowing of the sinus walls as noted on cone-beam computed tomographic imaging.