• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.5
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• pp.365-374
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• 2011

Introduction: Research on dental bone graft material has been actively conducted. Recently, demineralized dentin matrix material has been developed and introduced. This study examined the effect of demineralized dentin matrix material on bone healing. Subjects and Methods: The patients who received no treatment after extraction were used as the control group and patients who underwent demineralized dentin matrix material application in the extraction socket after extraction were used as the experimental group. Panorama radiography was performed at the baseline and at 3.5 months after graft material placement and CT was taken at 3.5 months after graft material placement for a radiologic evaluation. Bony tissue specimens were collected from the alveolar crest in the middle of the extraction socket using a 2 mm trephine bur after 3.5 months for the histology and hostomorphometric study. Results: 1. On the panoramic view, a higher bone density was observed in the subject group. 2. On the panoramic view, the bone density increased significantly in the extraction socket, from the baseline to 3.5 months: a 7 and 10 gray-level scale was observed in the control and experimental group, respectively (P<0.05). 3. The CT view evaluation at 3.5 months revealed significantly higher bone density in the subject group than the control group (P<0.05). 4. The histological findings showed more active new bone and lamellar bone formation in the subject group. Dentin with osteoinduction ability and enamel with osteoconduction ability appeared. 5. On histomorphometric analysis, the subject group showed significantly more new bone, lamellar bone area and lower soft tissue area (P<0.05). The difference between the groups was significant (P<0.05). Conclusion: Bone healing was improved after the application of demineralized dentin matrix material and there was active new bone and lamellar bone formation.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.245-250
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• 2007

This research measured the shielding rates of apron 0.25 and 0.5 mmPb for X-ray energy in diagnosis radiation system and gamma-ray energy of $^{99m}Tc$-MDP and $^{18}F$-FDG. X-ray energies were measured on effective energy of $26.2{\sim}45.6\;keV$ when additional filtering plate of 0, 2 mmAl is used within the range of tube voltage $40{\sim}120\;kVp$, and at this time, apron 0.5 mmPb has shown about 5.5% of increase in its shielding rate over 0.25 mmPb at the highest quality. Besides, the aprons of the two types have shown high shielding rate of over 90% for direct X-ray and spatial dose rate. And, in case 0.25 and 0.5 mmPb aprons were used at 140keV of $^{99m}Tc$-MDP, the shielding effects were between 30 and 53%, and at high energy of 511 keV, $^{18}F$-FDG, the shielding effects of apron, $1.3{\sim}3.6%$, were very small.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.271-280
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• 2007

The objectives of this study were to identify the types of work values of radiological technology students and to verify the characteristics of them. The population of this study was the radiological technology students from 7 colleges randomly chosen in the whole country. data collected from 791 subjects were used. Types of work values were identified through the factor analysis and t-test between variables was used to determine the characteristics of the students. The research instrument used in this study was the Maryland Work Value Inventory(MWVI) designed by Meitus, R. The findings of this study were as follows ; 1. The types of work values of radiological technology students can be classified into 6 categories ; social contribution, achievement, capability, work interest, social status, economic reward. 2. Social contribution, achievement, capablity and work interest were classified as 'internal work values', while social status and economic reward as 'external work values'. 3. Work values of the radiological technology students were economic reward, social status, achievement, capablity, work interest, social contribution in order. 4. External work values of the radiological technology students got higher grade than internal work values.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.369-369
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• 2007

The physical and visual evaluation of the identical X-rays are analyzed for medical image clarity with CD-RAD Phantom on this study. The method of measurement is to research CD-RAD by X-rays and to acquire images through image processing equipment, the image analyses are carried out by physical evaluation with statistical method through CD-RAD analyser program, and the visual evaluation of the identical X-rays is carried out by blind test for 20 observers. The result of it is that IQF value of the physical evaluation of Contrast-detail curve is 25 and IQF value of the visual evaluation is 30, so it is revealed that the physical evaluation is superior to the visual one. The special qualities of medical images have much importance of the transmission capacity of information to the image analyser, so it is concluded that 0비ective methods of the physical and visual analyses should be carried out side by side.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.841-847
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• 2021

Related institutions that use radiation are diverse in Korea, such as research, medical care, and education. Recently, the number of examinations and visits to medical institutions is increasing. As a result, the number of radiological examinations in medical institutions is increasing. Radiation safety management is necessary as well as exposure of radiation workers. For safety management, first of all, it is necessary to wear the personal exposure dosimeter correctly and measure it accurately after wearing it. This study tries to evaluate and verify the measurement straightness of PLD devices by radiation of a diagnostic generator. Radiation division irradiation time interval was measured after irradiating 10 times at 10, 30, and 60 sec and irradiating the irradiation distance from 30 to 100 cm at 10 cm intervals to measure the change in absorbed dose depending on the distance. As a result, there was no difference in absorbed dose by time interval. This is considered to be helpful in various studies by using a diagnostic generator for the study of high absorbed dose.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.652-664
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• 2022

The Kernohan-Woltman notch phenomenon (KWNP) refers to an intracranial lesion causing massive side-to-side mass effect which leads to compression of the contralateral cerebral peduncle against the free edge of the cerebellar tentorium. Diagnosis is based on "paradoxical" motor deficit ipsilateral to the lesion associated with radiologic evidence of damage to the contralateral cerebral peduncle. To date, there is scarce evidence regarding KWNP associated neuroimaging patterns and motor function prognostic factors. A systematic review was conducted on Medline database from inception to July 2021 looking for English-language articles concerning KWNP, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The research yielded 45 articles for a total of 51 patients. The mean age was 40.7 years-old and the male/female sex ratio was 2/1. 63% of the patients (32/51) suffered from head trauma with a majority of acute subdural hematomas (57%, 29/51). 57% (29/51) of the patients were in the coma upon admission and 47% (24/51) presented pupil anomalies. KWNP presented the neuroimaging features of compression ischemic stroke located in the contralateral cerebral peduncle, with edema in the surrounding structures and sometimes compression stroke of the cerebral arteries passing nearby. 45% of the patients (23/51) presented a good motor functional outcome; nevertheless, no predisposing factor was identified. A Glasgow coma scale (GCS) of more than 3 showed a trend (p=0.1065) toward a better motor functional outcome. The KWNP is a regional compression syndrome oftentimes caused by sudden and massive uncal herniation and leading to contralateral cerebral peduncle ischemia. Even though patients suffering from KWNP usually present a good overall recovery, patients with a GCS of 3 may present a worse motor functional outcome. In order to better understand this syndrome, future studies will have to focus on more personalized criteria such as individual variation of tentorial notch width.

• Korean Journal of Radiology
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• v.22 no.2
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• pp.225-232
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• 2021

Objective: To determine whether changes in the transiting nerve rootlet or its surroundings, as seen on MRI performed after lumbar hemilaminectomy, are associated with persistent postoperative pain (PPP), commonly known as the failed back surgery syndrome. Materials and Methods: Seventy-three patients (mean age, 61 years; 43 males and 30 females) who underwent single-level partial hemilaminectomy of the lumbar spine without postoperative complications or other level spinal abnormalities between January 2010 and December 2018 were enrolled. Two musculoskeletal radiologists evaluated transiting nerve rootlet abnormalities (thickening, signal alteration, distinction, and displacement), epidural fibrosis, and intrathecal arachnoiditis on MRI obtained one year after the operations. A spine surgeon blinded to the radiologic findings evaluated each patient for PPP. Univariable and multivariable analyses were used to evaluate the association between the MRI findings and PPP. Results: The presence of transiting nerve rootlet thickening, signal alteration, and ill-distinction was significantly different between the patients with PPP and those without, for both readers (p ≤ 0.020). Conversely, the presence of transiting nerve rootlet displacement, epidural fibrosis, and intrathecal arachnoiditis was not significantly different between the two groups (p ≥ 0.128). Among the above radiologic findings, transiting nerve rootlet thickening and signal alteration were the most significant findings in the multivariable analyses (p ≤ 0.009). Conclusion: On MRI, PPP was associated with transiting nerve rootlet abnormalities, including thickening, signal alterations, and ill-distinction, but was not associated with epidural fibrosis or intrathecal arachnoiditis. The most relevant findings were the nerve rootlet thickening and signal alteration.

• Journal of Veterinary Clinics
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• v.32 no.5
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• pp.410-416
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• 2015

Bone grafting is widely used to bridge major bone defects or to promote bone union. In the evaluation of bone defect regeneration, 5 mm-diameter defects were created in rabbit calvaria. Concerning biocompatibility, fibrous capsule thickness of CBHA (hydroxyapatite from cuttlebone) was significantly thinner than that of CB (cuttlebone) and CHA (hydroxyapatite from coral) (p < 0.05) at 2 and 4 weeks after implantation. Concerning 12-week total changes of radiologic gray-level histogram, CBHA was significantly higher than CHA (p < 0.05). In the evaluation of bone defect regeneration, bone formation of CHA was significantly higher than that of CB and CBHA (p < 0.05). Based on the clinical and histological results, CBHA would be a safe material for use inside the body and has more effective osteoconduction than CB. It is suggested that CBHA is a valuable bone graft material.

• Imaging Science in Dentistry
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• v.54 no.1
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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.

• Journal of radiological science and technology
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• v.39 no.3
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• pp.399-406
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• 2016

Near-infrared radiation (NIR) is non-ionizing, non-invasive, and deep tissue penetration in biological material, thereby increasing research interests as a medical imaging technique in the world. However, the use of current near-infrared medical image is extremely limited in Korea (ROK) since it is not well known among radiologic technologists and radiological researchers. Therefore to strengthen the knowledge for NIR medical imaging is necessary so as to prepare a qualified radiological professionals to serve medical images in high-quality on the clinical sites. In this study, an overview of the features and principles of NIR imaging was demonstrated. The latest research topics and worldwide research trends were introduced for radiologic technologist to reinforce their technical skills. In particular, wound care and diabetic foot which have high feasibility for clinical translation were introduced in order to contribute to accelerating NIR research for developing the field of radiological science.