• Imaging Science in Dentistry
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• v.47 no.3
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• pp.209-213
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• 2017

Central giant cell lesions are rare, benign, osteolytic, pseudocystic, solitary, localized lesions that are common in the skeletal structure, but less so in the maxillofacial region. Furthermore, to perform panoramic radiography and cone-beam computed tomography, it is necessary to prepare patients properly and to position their heads carefully. However, this can be difficult in pediatric patients, who may be anxious. In this report, we describe the case of a central giant cell lesion of the mandible in a 2-year-old girl that was evaluated with multidetector computed tomography.

• Imaging Science in Dentistry
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• v.49 no.3
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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 radiological science and technology
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• v.43 no.5
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• pp.343-351
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• 2020

This study analyzed dose reduction and quality of images through dose reduction tools and shielding board to protect sensitive eye lens in radiation during orbit CT examinations for clinical data use. During CT scans of the phantom, surface dose (CT scanner dosimetry phantom, ion chamber-3 times) and quality of image (radiosurgery head phantom, visual assessment-2 times, HU standard deviation) were evaluated using X-care which is dose reduction tools and bismuth shielding board. The results of experiments of eight conditions showed a relatively reduced dose in all other conditions compared to when no conditions were set. In particular, the area corresponding to the ophthalmic part reduced the surface dose by up to 45.7 %. The visual evaluation of images by specialists and the quality evaluation of images analyzed by HU standard deviation were clinically closest to the use of X-care and shielding board (1 cm in height). Therefore, it is believed that the use of shielding board in a suitable location with dose reduction tools while investigating the optimal radiation dose will reduce the exposure dose of sensitive lens at radiation while maintaining the quality of the images with high diagnostic value.

• Journal of radiological science and technology
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• v.9 no.1
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• pp.93-123
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• 1986

The aim of this study is to propose the desirable plan of the diagnostic radiology department in general hospital. The main contents and results of this study are as follows. 1. By investigating and analyzing the activities and circulation of the patients and staffs in diagnostic radiology department, the activity model of the department was extracted. 2. The types of operating system of the department were extracted and activity model by the operating systems were made. 3. The types of the plan of the department were classified into three types, such as confusing-corridor type, separated-corridor type and contract type. 4. After dividing them into eight types in detail, the merits and demerits of each type were analyzed. 5. Among those types contact types were evaluated best in comparison with the other types in terms of efficiency of staff's work, access of patients to staffs and reduction of staffs movement.

• Imaging Science in Dentistry
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• v.36 no.1
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• pp.63-68
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• 2006

Desmoplastic ameloblastoma is a rare histologic variant of ameloblastoma. It shows important differences in anatomic distribution, histologic appearance, and radiographic findings compared with the general type of ameloblastoma. It is histologically characterized by an abundance of densely collagenous stroma and radiographically a mixed radiolucent-radiopaque lesion. We present three cases of desmoplastic ameloblastoma. All the patients complained on buccal swelling with or without pain and the sites of occurrence were the anterior and the premolar region. Plain radiographs showed mixed radiopaque-radiolucent lesion with ill-defined or diffuse sclerotic margin and no external root resorption. Additionally, CT scans revealetl buccal expansion and relatively well-defined margin of the lesions. The clinical and radiographic features of the presented cases were compared with those of the desmoplastic ameloblastoma in the previous literatures.

• Imaging Science in Dentistry
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• v.42 no.4
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• pp.207-212
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• 2012

Purpose: This study was performed to determine the relative frequency of positioning errors, to identify those errors directly responsible for diagnostically inadequate images, and to assess the quality of panoramic radiographs in a sample of records collected from a dental college. Materials and Methods: This study consisted of 1,782 panoramic radiographs obtained from the Department of Oral and Maxillofacial Radiology. The positioning errors of the radiographs were assessed and categorized into nine groups: the chin tipped high, chin tipped low, a slumped position, the patient positioned forward, the patient positioned backward, failure to position the tongue against the palate, patient movement during exposure, the head tilted, and the head turned to one side. The quality of the radiographs was further judged as being 'excellent', 'diagnostically acceptable', or 'unacceptable'. Results: Out of 1,782 radiographs, 196 (11%) were error free and 1,586 (89%) were present with positioning errors. The most common error observed was the failure to position the tongue against the palate (55.7%) and the least commonly experienced error was patient movement during exposure (1.6%). Only 11% of the radiographs were excellent, 64.1% were diagnostically acceptable, and 24.9% were unacceptable. Conclusion: The positioning errors found on panoramic radiographs were relatively common in our study. The quality of panoramic radiographs could be improved by careful attention to patient positioning.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1858-1874
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• 2021

Recent advances in the molecular and genetic characterization of central nervous system (CNS) tumors have ushered in a new era of tumor classification, diagnosis, and prognostic assessment. In this emerging and rapidly evolving molecular genetic era, imaging plays a critical role in the preoperative diagnosis and surgical planning, molecular marker prediction, targeted treatment planning, and post-therapy assessment of CNS tumors. This review provides an overview of the current imaging methods relevant to the molecular genetic classification of CNS tumors. Specifically, we focused on 1) the correlates between imaging features and specific molecular genetic markers and 2) the post-therapy imaging used for therapeutic assessment.

• Korean Journal of Radiology
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• v.20 no.1
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• pp.69-82
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• 2019

In 2017, the American Joint Committee on Cancer announced the 8th edition of its cancer staging system. For breast cancer, the most significant change in the staging system is the incorporation of biomarkers into the anatomic staging to create prognostic stages. Different prognostic stages are assigned to tumors with the same anatomic stages according to the tumor grade, hormone receptor (estrogen receptor; progesterone receptor) status, and HER2 status. A Clinical Prognostic Stage is assigned to all patients regardless of the type of therapy used; in contrast, a Pathologic Prognosis Stage is assigned to patients in whom surgery is the initial treatment. In a few situations, low Oncotype DX recurrence scores can change the prognostic stage. The radiologists need to understand the importance of the biologic factors that can influence cancer staging.

• Journal of radiological science and technology
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• v.42 no.5
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• pp.329-334
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• 2019

This study was purpose to quantitative evaluation of noise power spectrum(NPS) and studied the quantitative evaluation and characteristics of modulation transfer function(MTF) by obtain the optimal edge image by using Coil in magnetic resonance imaging(MRI) equipment through Fujita theory using edge method. The MRI equipment was used (Tim AVANTO 1.5T, Siemense healthcare system, Germany) and the head matrix coil were 12channels(elements) receive coil. The NPS results of showed the best value of 0.004 based on the T2 Nyquist frequency of $1.0mm^{-1}$, and the MTF results of showed that the T1 and T2 values were generally better than the T1 CE and T1 CE FC values. The characteristics of this study were to explain the characteristic method of image quality evaluation in general. To present the quantitative evaluation process and results in the evaluation of MRI image characteristics in radiology.

• Journal of radiological science and technology
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• v.46 no.2
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• pp.99-106
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• 2023

The height of the table should be considered important during computed tomography (CT) examination, but according to previous studies, not all radiology technologists set the table at the patient's center at the examination, which affects the exposure dose and image quality received by the patient. Therefore, this study intends to study the image quality exposure dose according to the height of the table to realize the optimal image quality and dose during the brain CT scan. The head phantom images were acquired using Philips Brilliance iCT 256. When the image was acquired, the table height was adjusted to 815, 865, 915, 965, 1015, and 1030 mm, respectively, and each scan was performed 3 times for each height. For the exposure dose measurement, optically stimulated luminescence dosimeter (OSLD) was attached to the front, side, eye, and thyroid gland of the head phantom. In the signal to noise ratio (SNR) measurement result, The SNR values for each table height were all lower than 915 mm. As a result of exposure dose, the exposure dose on each area increased as the table height decreased. The height of the table has a close relationship with the patient's radiation exposure dose in the CT scan.