• Imaging Science in Dentistry
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• 제49권1호
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• pp.53-58
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• 2019

Purpose: To present characteristic findings of Tc-99m hydroxymethylene diphosphonate (HMDP) scintigraphy, computed tomography (CT), and magnetic resonance (MR) imaging for osteonecrosis in the mandible, especially osteoradionecrosis(ORN) and medication-related osteonecrosis of the jaw(MRONJ). Materials and Methods: Thirteen patients with MRONJ and 7 patients with ORN in the mandible underwent Tc-99m HMDP scintigraphy, CT, and MR imaging (T1-weighted images[T1WI], T2-weighted images[T2WI], short inversion time inversion recovery images[STIR]), diffusion-weighted images[DWI], and apparent diffusion coefficient [ADC] mapping). The associations of scintigraphy, CT, and MR imaging findings with MRONJ and ORN were analyzed using the chi-square test with the Pearson exact test. Results: Thirteen patients with MRONJ and 7 patients with ORN in the mandible showed low signal intensity on T1WI and ADC mapping, high signal intensity on STIR and DWI, and increased uptake on scintigraphy. Periosteal bone proliferation on CT was observed in 69.2% of patients with MRONJ(9 of 13) versus 14.3% of patients with ORN(1 of 7)(P=0.019). Conclusion: This study presented characteristic imaging findings of MRONJ and ORN on scintigraphy, CT, and MR imaging. Our results suggest that CT can be effective for detecting MRONJ and ORN.

• 대한수의학회지
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• 제52권3호
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• pp.205-208
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• 2012

Endocrine test data from a 13-year old intact female Maltese was indicative of the presence of an insulinoma, however ultrasonography identified a pancreatic mass only after 10 months after the first admission. Following identification of both pancreatic tumor and hepatic metastasis on computed tomography (CT), surgical excision of the mass was attempted. However, total excision failed because of tumor adhesion to adjacent large vessels. The pancreatic mass was monitored over the next 25 months via ultrasonography, CT, and positron emission tomography-computed tomography (PET-CT). Histopathological and immunohistochemical data confirmed the diagnosis of insulinoma with hepatic metastasis.

• 대한의용생체공학회:의공학회지
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• 제29권1호
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• pp.46-51
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• 2008

We describe a backprojection filtering method for limited angle tomography. In order to reduce blur artifacts originated from the out-of-planes and control high-frequency noise, we employed two band-limited window functions, and which were realized by Hann filters in this study. Based on the experimentally measured data, the performance of the developed method is demonstrated by comparing with the conventional shift-and-add and filtered backprojection methods. Application of the developed method to the dental imaging has a potential to be used for the preoperative evaluation of the jaw for dental implants with much reduced patient dose instead of the conventional dental computed tomography.

• 대한수의학회지
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• 제50권4호
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• pp.311-317
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• 2010

Recently the micropig has been developed as human disease model. The dental and orofacial region of micropig is similar to that of humans, so it has been used for testing implant materials and techniques. The purpose of this study is on dental image at each age using radiography and computed tomography. Total twenty-two male micropigs, two or three animals of each 1, 3, 5, 7, 9, 12, 18 and 24 months old, were given radiographic examinations. After general anesthesia, extra- and intra-oral radiographic technique and computed tomographic scans were performed to assess the dental characterization of micropigs. The total deciduous dental formula comprised 28 teeth and was depicted as Di 3/3, Dc 1/1, Dp 3/3. The total permanent dental formula comprised 44 teeth and was depicted as I 3/3, C 1/1, P 4/4, M 3/3. Hypodontia of the first premolars was common in the micropig. The permanent teeth erupted from 3 to 24 month after birth. The sequence of eruption of the permanent teeth was M1, P1, I3, C, M2, I1 + P3 + P4, P2, I2, M3. Dental imaging enables visualization of the unerupted teeth and gives more information about the development of the teeth. The growth pattern of the teeth obtained through radiographic and computed tomographic examination provides basic data in the micropig as animal model for dental research.

• Archives of Plastic Surgery
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• 제32권5호
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• pp.589-592
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• 2005

Since G.N. Hounsfield's clinical use of computed tomography in 1971, digital imaging technique using computers has shown an eye opening progress. Progress has made 3-dimensional understanding of not only facial bones but muscles and other connective tissues possible through 3-dimensional reconstruction of preexisting tomographical images. Also, quantitative analysis of density, distance, volume has become possible, allowing objective analysis of preoperative and postoperative states through imaging. The authors measured the masseter muscle volume of 20 normal individuals and 8 female patients through 3-D reconstructive CT imaging and made a statistical analysis of the measurements. The method used in our study may be applied to the diagnosis of disease causing the change of the facial volume and presurgical design as a useful tool to provide objective information on the evaluation of surgery outcome.

• Imaging Science in Dentistry
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• 제51권3호
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• pp.313-321
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• 2021

Ankylosis of the temporomandibular joint (TMJ) is a disabling disease resulting from fibrous or bony fusion of the mandibular condyle and the glenoid fossa. Early diagnosis and surgical treatment are essential to prevent facial deformity and other complications. Conventional radiography has limitations in demonstrating the true extent of ankylosis. It is important for surgeons to be aware of the size and degree of bony ankylosis in order to perform complete resection of the ankylotic mass. In addition, a detailed evaluation of the relationship with adjacent vital structures such as the internal maxillary artery, inferior alveolar nerve canal, external auditory canal, and skull base are crucial to avoid iatrogenic injury. Multidetector computed tomography (MDCT) is the current imaging modality of choice for preoperative assessments. Herein, the authors propose a structured CT reporting template for TMJ ankylosis to strengthen the value of the preoperative imaging report and to reduce the rates of intraoperative complications and recurrence.

• Imaging Science in Dentistry
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• 제54권1호
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• pp.115-120
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• 2024

Components derived from an infected lesion within the bone can spread through various passages in the mandible, particularly via the mental foramen. Radiologically, the spread of infection is typically nonspecific and challenging to characterize; however, multislice computed tomography (MSCT) can effectively detect pathological changes in soft tissues and the bone marrow space. This report describes the case of a 55-year-old woman who experienced mental nerve paresthesia due to a periapical infection of the right mandibular second premolar. MSCT imaging revealed increased attenuation around the periapical lesion extending into the mandibular canal and loss of the juxta-mental foraminal fat pad. Following endodontic treatment of the tooth suspected to be the source of the infection, the patient's symptoms resolved, and the previous MSCT imaging findings were no longer present. Increased bone marrow attenuation and obliteration of the fat plane in the buccal aspect of the mental foramen may serve as radiologic indicators of inflammation spreading from the bone marrow space.

• BMB Reports
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• 제55권6호
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• pp.267-274
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• 2022

Molecular imaging is used to improve the disease diagnosis, prognosis, monitoring of treatment in living subjects. Numerous molecular targets have been developed for various cellular and molecular processes in genetic, metabolic, proteomic, and cellular biologic level. Molecular imaging modalities such as Optical Imaging, Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Computed Tomography (CT) can be used to visualize anatomic, genetic, biochemical, and physiologic changes in vivo. For in vivo cell imaging, certain cells such as cancer cells, immune cells, stem cells could be labeled by direct and indirect labeling methods to monitor cell migration, cell activity, and cell effects in cell-based therapy. In case of cancer, it could be used to investigate biological processes such as cancer metastasis and to analyze the drug treatment process. In addition, transplanted stem cells and immune cells in cell-based therapy could be visualized and tracked to confirm the fate, activity, and function of cells. In conventional molecular imaging, cells can be monitored in vivo in bulk non-invasively with optical imaging, MRI, PET, and SPECT imaging. However, single cell imaging in vivo has been a great challenge due to an extremely high sensitive detection of single cell. Recently, there has been great attention for in vivo single cell imaging due to the development of single cell study. In vivo single imaging could analyze the survival or death, movement direction, and characteristics of a single cell in live subjects. In this article, we reviewed basic principle of in vivo molecular imaging and introduced recent studies for in vivo single cell imaging based on the concept of in vivo molecular imaging.

• 한국임상수의학회지
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• 제20권4호
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• pp.523-526
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• 2003

Three dimensional computed tomographic images were obtained in two cases with trauma. The first case of a 3 year-old male Maltese, with ataxia and head tilting due to head trauma was referred to veterinary medical teaching hospital, Seoul National University. Remarkable findings were not found on survey radiographs. With the help of three-dimensional reconstruction computed tomographic imaging, parietal and occipital bone fracture was identified. The second case of 4 month-old female Yorkshire terrier with left forelimb lameness was referred right after trauma. Survey radiography showed obvious incongruity of the elbow joint. Lateral and medial condyle of the left humerus fracture and lateral displacement of the left ulna were apparent in three-dimensional computed tomographic image. It was considered that three-dimensional computed tomography could be used as an aid modality for the exact evaluation of extends and degree of fracture as well as planning of orthopedic surgery.

• 대한치과의사협회지
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• 제52권1호
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• pp.27-36
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• 2014

The introduction of cone-beam computed tomography(CBCT) and computer software in dentistry has allowed orthodontists and maxillofacial surgeons to provide more accurate diagnosis and treatment. In this article, a facial asymmetry patient who had orthodontic treatment combined with orthognathic surgery using CBCT imaging is introduced and the way how CBCT imaging could be applied in clinical orthodontics and orthognathic surgery is explained. Also, evaluation of treatment outcomes using CBCT is suggested. More accurate, predictable and efficient surgical orthodontic planning and treatment are expected in the near future through cutting edge medical imaging including CBCT and CAD/CAM technologies.