• 한국방사선학회논문지
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• 제11권5호
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• pp.371-377
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• 2017

일반 X선 촬영 실습용 팬텀은 방사선학과에 없어서는 안 되는 중요한 교재나 기존의 시판되는 팬텀은 고가의 수입품이기에 다양한 종류의 팬텀을 갖추는 것이 어렵다. 3D 프린팅 기술을 활용해 일반 X선 촬영 실습용 팬텀을 더욱 저렴하고 간편하게 제작해 보고자 한다. CT 영상 데이터를 기반으로 제작한 골격 모형을 FDM(Fused Deposition Modeling) 방식의 3D printer를 이용해 출력한 골격 모형을 일반 X선 촬영 실습용 팬텀으로써 사용해 보고자 한다. 3D slicer 4.7.0 프로그램을 이용해 CT DICOM 영상 데이터를 STL 파일로 변환하고 G-code 변환 과정을 거쳐 3D 프린터로 출력하여 골격 모형을 제작한다. 완성된 팬텀을 X선 촬영, CT 촬영하여 실제 의료 영상, 시판되는 팬텀과 비교해 본 결과 실제 의료영상과 골 밀도 등의 세부적인 차이가 존재하였으나 실습용 팬텀으로써 활용할 수 있다고 판단되었다. 저가화되어 보급된 3D 프린터와 연구용으로 무료 배포된 3D slicer 프로그램을 활용하여 저렴하면서도 일반 X선 촬영 실습에 사용하는 것이 가능한 팬텀을 제작할 수 있었다. 앞으로의 3D 프린팅 기술의 다양화와 연구에 따라 보건 교육, 의료 서비스 등 여러 분야에 적용하는 것이 가능할 것이다.

• Imaging Science in Dentistry
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• 제43권3호
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• pp.179-184
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• 2013

Purpose: X-ray exposure should be clinically justified and each exposure should be expected to give patients benefits. Since dental radiographic examination is one of the most frequent radiological procedures, radiation hazard becomes an important public health concern. The purpose of this study was to investigate the attitude of Korean dentists about radiation safety and use of criteria for selecting the frequency and type of radiographic examinations. Materials and Methods: The study included 267 Korean dentists. Five questions related to radiation safety were asked of each of them. These questions were about factors associated with radiation protection of patients and operators including the use of radiographic selection criteria for intraoral radiographic procedures. Results: The frequency of prescription of routine radiographic examination (an example is a panoramic radiograph for screening process for occult disease) was 34.1%, while that of selective radiography was 64.0%. Dentists' discussion of radiation risk and benefit with patients was infrequent. More than half of the operators held the image receptor by themselves during intraoral radiographic examinations. Lead apron/thyroid collars for patient protection were used by fewer than 22% of dental offices. Rectangular collimation was utilized by fewer than 15% of dental offices. Conclusion: The majority of Korean dentists in the study did not practice radiation protection procedures which would be required to minimize exposure to unnecessary radiation for patients and dental professionals. Mandatory continuing professional education in radiation safety and development of Korean radiographic selection criteria is recommended.

• 대한치과의사협회지
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• 제52권3호
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• pp.153-163
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• 2014

3-dimensional information for anatomic stucture plays a role as integral part in clinical aspect of dental practice. CBCT(cone beam computed tomography) has been accepted as useful diagnostic tool offering Volume data and images for evaluating teeth and jaws in lower radiation dose than conventional CT. CBCT equipment is essential for the quality assurance of it to ensure continued satisfactory performance and result of adequate images. Dental practitioner and oral and maxillofacial radiologist should have a responsibility and critical thinking to deliver this technology to patients in a responsible way, so that diaganostic value is maximised and radiation doses kept as low as resonably achievable. CBCT imaging modality should be used only after a review of the patient's health and imaging history and the completion of a thorough clinical examination. Clinical guidelines are systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances Dental practitioners should prescribe CBCT imaging only when they expect that the diagnostic yield will benefit patient care, enhance patient safety or improve clinical outcomes significantly. Knowledge of patient dose is essential for clinicians who are making the decision regarding the justification of the exposure. There are some limitation in the measurement of patient dose in CBCT for the approval and adaptation of conventinal methodolgy in CT. It is also important to ensure that doses are optimised and in line with any national and international guidelines. The higher radiation doses of CBCT compared with conventional radiography, mean that high standards must be maintained. The Quality Assurance(QA) programme should entail surveys and checks that are performed according to a regular timetable. QA programme should be maintained by staff to ensure adherence to the programme and to raise its importance among staff.

• 한국방사선학회논문지
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• 제8권7호
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• pp.377-382
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• 2014

방사선 임상 관련 분야에서 컴퓨터의 사용으로 인해 카세트 사용에서는 볼 수 없는 아티팩트가 만들어지고 있다. 고스팅 아티팩트는 평판형 박막 트랜지스터(Flat Panel Thin-Film Transistor) 배열 검출기를 사용할 때 발생될 수 있다. 특히 고선량의 방사선을 고대조도의 물질에 노출시킨 영상을 획득한 후, 바로 저선량의 조사가 이루어진 영상이 획득될 때 고스팅 아티팩트가 발생할 수 있다. 본 실험에서 고스팅 아티팩트가 육안 관찰시 3분에서 사라지는 것을 확인할 수 있었으며 정량적 분석으로는 대략 6분에서 없어지는 것을 확인할 수 있었다. 또한 이 아티팩트는 관전류보다는 관전압의 영향을 더 받는다는 사실과 노출에 의한 포획전하의 방출이 아닌 시간에 의해 포획전하가 소멸된다는 사실을 실험을 통해 검증할 수 있었다.

• Clinics in Shoulder and Elbow
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• 제20권2호
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• pp.84-89
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• 2017

Background: Common and effective treatments for calcific tendinitis involve needling procedures. However, it has been widespread practice to refer patients with calcific tendinitis, which is a predominantly orthopedic condition, to radiology department. The purpose of this study was to compare clinical and radiological outcomes after ultrasound-guided needling for calcific tendinitis between the orthopedics and radiology department. Methods: Seventy-seven shoulders (Group 1) and 38 shoulders (Group 2) treated in the radiology and orthopedic department, respectively. A fellowship-trained orthopedic surgeon and a musculoskeletal radiologist each performed the procedure of ultrasound-guided needle decompression with subacromial steroid injection. Clinical outcomes was evaluated using the visual analogue scale for pain (pVAS) and the American Shoulder and Elbow Surgeons (ASES) shoulder score before treatment and at each follow-up. The pre- and postneedling size and shape of the calcific deposits were compared between the two groups. Results: We analyzed a total of 56 shoulders for Group 1 and 32 shoulders for Group 2. The mean age and sex ratio of the patients no significantly different. We found that the mean decrease in the diameter of calcification between pre- and post-needling was 9.0 mm for Group 1 and 13.1 mm for Group 2; the difference was significantly larger in Group 2 than in Group 1. Both groups showed improved pVAS and ASES scores after needling but the extent of these improvements did not differ with the type of operator. Conclusions: Needling decompression performed by orthopedic surgeons could a viable option for the treatment of calcific tendinitis.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2383-2391
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• 2014

Tobacco use is described as the single most preventable cause of morbidity and mortality globally, with the World Bank predicting over 450 million tobacco-related deaths in the next fifty years. In India, the proportion of all deaths that can be attributed to tobacco use is expected to rise from 1.4% in 1990 to 13.3% in 2020 of which smoking alone will cause about 930,000 adult deaths by 2010. Many studies have shown that counseling from a health professional is an effective method of helping patients quit the tobacco habit. Tobacco cessation needs to be urgently expanded by training health professionals in providing routine clinical interventions, increasing availability and subsidies of pharmacotherapy, developing wide-reaching strategies such as quitlines, and costeffective strategies, including group interventions. The WHO Framework Convention on Tobacco Control (FCTC) emphasizes the vital contribution of participation of health professional bodies, as well as training and healthcare institutions in tobacco control efforts. Dentists can play an important role in helping patients quit using tobacco. One of the key strategies to reduce tobacco-related morbidity and mortality is to encourage the involvement of health professionals in tobacco-use prevention and cessation counselling. The dental office is an ideal setting for tobacco cessation services since preventive treatment services, oral screening, and patient education have always been a large part of the dental practice.

• Investigative Magnetic Resonance Imaging
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• 제24권3호
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• pp.132-140
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• 2020

Purpose: To retrospectively determine whether specialized magnetic resonance imaging (MRI) reading performed by an experienced radiologist affected the successful assessment of extraprostatic extension (EPE) in the presence of biopsy-related hemorrhage after prostate biopsy. Materials and Methods: Two hundred consecutive patients with biopsy-proven prostate cancer underwent MRI. General radiologist and subspecialized radiologist readings were unpaired and reviewed in random order by a radiologist who was blinded to patients' clinical details and histopathologic data. The extent of hemorrhage was assessed on T1-weighted (T1W) MRI using a 1-4 scale, and the likelihood of EPE was assessed for each of the four categories. Histopathologic specimens served as the reference standard. The area under the curve (AUC) of the standard reading was compared to that of the specialized reading. Results: Post-biopsy hemorrhage was subjectively graded as ≥ 3 in 101 patients (50.5%) by standard reading, and in 100 patients (50.0%) by specialized reading. The standard and specialized readings disagreed for 40 (20.7%) of the patients (kappa [κ] = 0.35; 95% CI, 0.14-0.48). Of these, specialized reading was the correct interpretation for 21 patients (52.5%). The sensitivity (75% vs. 44%; P = 0.002) and area under the receiver operating characteristics (AUROC) (0.83 vs. 0.67; P = 0.008) of the specialized readings were significantly higher than those of the standard readings, while there was no significant difference in specificity (84% vs. 87%; P = 0.434). Conclusion: The reinterpretation of MRI by experienced radiologists significantly improves the diagnosis of EPE in prostate cancer in the presence of post-biopsy hemorrhage.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2002년도 춘계학술대회 및 총회
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• pp.17-24
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• 2002

Recurrence of colorectal cancer after apparently curative resection remains common, with reported relapse rates of up to 40%. Because complete resection of solitary metastases or local recurrence may improve long-term survival, surgical management of such cases has become increasingly aggressive but has led to only modest survival benefit. The limitations of current approaches based on structural imaging are well documented, with over half of the patients who are thought suitable for curative surgery being found to have unresectable disease at operation. Therefore, better preoperative assessment is crucial. The increasing use of FDG-PET as an oncologic staging investigation has significantly improved the assessment of patients with suspected colorectal cancer recurrence. Several studios show that substantial and largely appropriate changes in patient management occur, often soaring patients the significant morbidity and mortality associated with aggressive but futile therapies while also saving scarce community resources. Nevertheless, the clinical relevance of these findings has still been questioned. The utility of PET in routine clinical practice will likely depend on its ability to provide incremental information compared with CT in selected patients rather than to serve as a replacement for CT. In conclusion, in patients with suspected recurrent or metastatic colorectal carcinoma, FDG-PET should be performed (1) when there is rising carcinoembryonic antigen levels in the absence of a known source, (2) to increase the specificity of structural imaging when there is an equivocal lesion, and (3) as a screening method for the entire body in the preoperative staging before curative resection of recurrent disease.

• Imaging Science in Dentistry
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• 제46권1호
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• pp.9-16
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• 2016

Purpose: To evaluate the upper airway dimensions of obstructive sleep apnea (OSA) and control subjects using a cone-beam computed tomography (CBCT) unit commonly applied in clinical practice in order to assess airway dimensions in the same fashion as that routinely employed in a clinical setting. Materials and Methods: This was a retrospective analysis utilizing existing CBCT scans to evaluate the dimensions of the upper airway in OSA and control subjects. The CBCT data of sixteen OSA and sixteen control subjects were compared. The average area, average volume, total volume, and total length of the upper airway were computed. Width and anterior-posterior (AP) measurements were obtained on the smallest axial slice. Results: OSA subjects had a significantly smaller average airway area, average airway volume, total airway volume, and mean airway width. OSA subjects had a significantly larger airway length measurement. The mean A-P distance was not significantly different between groups. Conclusion: OSA subjects have a smaller upper airway compared to controls with the exception of airway length. The lack of a significant difference in the mean A-P distance may indicate that patient position during imaging (upright vs. supine) can affect this measurement. Comparison of this study with a future prospective study design will allow for validation of these results.

• 한국융합학회논문지
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• 제10권6호
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• pp.89-94
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• 2019

이 연구는 원자력안전법 개정에 따른 수시출입자 안전관리체계 개편이 적용된 방사선학과 재학생들의 인식도를 알아보고자 K 대학교 방사선학과 재학생 175명을 대상으로 설문조사를 실시하였다. 원자력안전법에 의해 수시출입자로 분류되어 관리를 받을 필요가 있다고 인식하는 재학생은 2학년 98.1%, 3학년 90.3%, 4학년 97.7%로 나타났으며, 수시출입자로 구분되어 촬영실습의 조작에 제한을 받는다는 재학생이 2학년 96.3%, 3학년 74.2%, 4학년 93.2%로 나타났다. 방사선촬영실습에서 방사선장비를 조작하는데 제한을 두는 것은 학생들의 학습권을 침해하는 규정으로 학습에 대한 예외규정을 제정하여 학습권이 침해받지 않도록 정책을 펼쳐나가야 할 것 이다.