• 제목/요약/키워드: Diagnostic errors

검색결과 148건 처리시간 0.029초

Telometer를 이용한 슬관절 측부인대 Stress-radiogram의 재현성 비교평가 (Comparative Evaluation of Reproducibility of Knee Joint Collateral Ligament Stress-radiogram Using Telometer)

  • 정진만;정성빈;김상현;이정훈
    • 대한방사선기술학회지:방사선기술과학
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    • 제41권6호
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    • pp.539-543
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    • 2018
  • Telometer is a supplementary filming device that improves the image quality and minimizes the motion unsharpness by enhancing the reproducibility of diagnostic images because it applies constant pressure (force) to the affected area. The stress-radiogram which is widely used to provide the o-bjective quantitative stability of knee ligament is reported in literature as the most suitable method to evaluate the stability of ligament and it is advised to use the Telometer. In order to evaluate the image reproducibility of the Telometer, the collateral ligament which is the most vulnerable among the ligaments consisting of the knee joint, the stress-radiogram was executed in the order of the Telometer, the push pull gauge and the conventional stress radiogram. Then, SPSS (Statistical Package for the Social Science) for Windows 22.0 was used for comparison and evaluation. According to the results of comparison and evaluation, the standard errors and standard deviations became smaller in the order of the Telometer, the push pull gauge, the conventional stress radiogram while the image reproducibility was higher in the order of the Telometer, the push pull gauge, the conventional stress radiogram. Therefore, it is considered that the use of the TELOS for stress-radiogram would enhance the quality of patient diagnostic images and the work performance of radiologists.

영상장치 센서 데이터 QC에 관한 연구 (A study on imaging device sensor data QC)

  • 윤동민;이재영;박성식;전용한
    • Design & Manufacturing
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    • 제16권4호
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    • pp.52-59
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    • 2022
  • Currently, Korea is an aging society and is expected to become a super-aged society in about four years. X-ray devices are widely used for early diagnosis in hospitals, and many X-ray technologies are being developed. The development of X-ray device technology is important, but it is also important to increase the reliability of the device through accurate data management. Sensor nodes such as temperature, voltage, and current of the diagnosis device may malfunction or transmit inaccurate data due to various causes such as failure or power outage. Therefore, in this study, the temperature, tube voltage, and tube current data related to each sensor and detection circuit of the diagnostic X-ray imaging device were measured and analyzed. Based on QC data, device failure prediction and diagnosis algorithms were designed and performed. The fault diagnosis algorithm can configure a simulator capable of setting user parameter values, displaying sensor output graphs, and displaying signs of sensor abnormalities, and can check the detection results when each sensor is operating normally and when the sensor is abnormal. It is judged that efficient device management and diagnosis is possible because it monitors abnormal data values (temperature, voltage, current) in real time and automatically diagnoses failures by feeding back the abnormal values detected at each stage. Although this algorithm cannot predict all failures related to temperature, voltage, and current of diagnostic X-ray imaging devices, it can detect temperature rise, bouncing values, device physical limits, input/output values, and radiation-related anomalies. exposure. If a value exceeding the maximum variation value of each data occurs, it is judged that it will be possible to check and respond in preparation for device failure. If a device's sensor fails, unexpected accidents may occur, increasing costs and risks, and regular maintenance cannot cope with all errors or failures. Therefore, since real-time maintenance through continuous data monitoring is possible, reliability improvement, maintenance cost reduction, and efficient management of equipment are expected to be possible.

상관분석과 회귀분석을 이용한 논문의 통계활용 분석 (Analysis on Reports of Statistical Testings for Correlation and Regression)

  • 조동숙;정재원;김증임;안숙희;박소미;박혜숙
    • 여성건강간호학회지
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    • 제14권3호
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    • pp.213-221
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    • 2008
  • Purpose: This study aimed to examine the accuracy and adequacy of research papers reporting statistical testings for correlation and regression. Method: Original research articles utilized correlation and regression analysis were reviewed from the Korean Journal of Women Health Nursing published from the year 2004 to 2006. Thirty-six papers were evaluated in accordance with formatted criteria in respect to an inclusiveness of research title, accuracy of statistical methods and presentation styles, and errors in reporting statistical outcomes. Result: Thirty articles (83.3%) utilized Pearson's correlational analysis, and ten articles did regression analysis. Lack of accurate understanding and interpretation of the statistical method was a main fault. Basic assumptions and diagnostic testings for each statistical method were not performed or described in most of the studies. Some points like consistency of research questions with statistical methods and criteria for sample size were still left out in part. Details of the presentation in the reporting of outcomes were not complied with the guidelines, which need careful concerns of the writers. Errors in English of result tables were found in more than one third of the tables. Conclusion: The outcome would be reflected in the submission guidelines for future writers. To reach the level comparable with internationally recognized nursing journals, concrete knowledge to apply statistical methods should be ensured in the processes of submission, reviews, and editing.

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진단용 CT-모의치료기 테이블의 효율적인 교정 방법 (An Efficient Correction Process of CT-Simulator Couch with Current Diagnostic CT Scanners)

  • 구은회;이재승;조정근;문성권
    • 한국콘텐츠학회논문지
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    • 제9권11호
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    • pp.254-261
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    • 2009
  • 본 연구는 진단용 CT 장치를 이용한 CT-모의치료기의 테이블 및 레이저 정렬 시스템과 횡단면 영상의 중심간 정렬을 개선하기 위한 효율적인 방법을 제안하고자 하였다. 본원에서 제작한 팬텀을 이용하여 AAPM TG66에서 제시하는 일일 정도관리를 시행하고 기하학적 삼각함수를 이용하여 레이저 정렬 시스템을 교정하였으며 교정 전, 후를 비교함으로서 교정방법에 대한 효율성을 검토하였다. 교정 전 영상의 중심간 오차는 3.82mm, 테이블 종축은 $0.436^{\circ}$ 틀어져 진행하였다. 기하학적 삼각함수를 이용한 레이저 정렬 시스템의 교정 후 0.7mm의 중심간 오차가 발생하여 ${\pm}2mm$의 허용오차 범위를 만족하였다. 설치 가동 중인 진단용 CT 장치를 방사선치료 전용 CT-모의치료기로 활용하는 경우 기하학적 정확도를 만족시키기 위한 테이블 교정은 기술적인 한계 뿐 만 아니라 시간 및 경제적 손실에 비하여 매우 비효율적이다. 그러나 레이저 정렬 시스템을 이용한 교정 방법은 경제적이고 비교적 간단하면서도 만족스러운 기하학적 정확도를 얻을 수 있어 임상에서 적용할 수 있는 효율적인 방법이라 사료된다.

철결핍성빈혈(鐵缺乏性貧血)에서 Cobalt($^{58}Co$)배설율검사(排泄率檢査)의 진단적(診斷的) 가치(價値) (Diagnostic Value of the Cobalt($^{58}Co$) Excretion Test in Iron Deficiency Anemia)

  • 신현정;홍기석;조경삼;송인경;고창순;이문호
    • 대한핵의학회지
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    • 제10권1호
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    • pp.21-34
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    • 1976
  • The diagnosis of iron deficiency rests upon the correct evaluation of body iron stores. Morphological interpretation of blood film and the red cell indices are not reliable and often absent in mild iron deficiency. Serum iron levels and iron-binding capacity are more sensitive indices of iron deficiency, but they are often normal in iron depletion and mild iron deficiency anemia. They are also subject to many variables which may introduce substantial errors and influenced by many pathologic and physiologic states. Examination of the bone marrow aspirate for stainable iron has been regarded as one of the most sensitive and reliable diagnostic method for detecting iron deficiency, but this also has limitations. Thus, there is still need for a more practical, but sensitive and reliable substitute as a screening test of iron deficiency. Pollack et al. (1965) observed that the intestinal absorption of cobalt was raised in iron-deficient rats and Valberg et al. (1969) found that cobalt absorption was elevated in patients with iron deficiency. A direct correlation was demonstrated between the amounts of radioiron and radiocobalt absorbed. Unlike iron, excess cobalt was excreted by the kidney, the percentage of radioactivity in the urine being directly related to the percentage absorbed from the gastrointestinal tract. Recently a test based on the urinary excretion of an oral dose of $^{57}Co$ has been proposed as a method for detecting iron deficiency. To assess the diagnostic value of urinary cobalt excretion test cobaltous chloride labelled with $1{\mu}Ci\;of\;^{58}Co$ was given by mouth and the percentage of the test dose excreted in the urine was measured by a gamma counter. The mean 24 hour urinary cobalt excretion in control subjects with normal iron stores was 6.1% ($1.9{\sim}15.2%$). Cobalt excretion was markedly increased in patients with iron deficiency and excreted more than 29% of the dose. In contrast, patients with anemia due to causes other than iron deficiency excreted less than 27%. Hence, 24 hour urinary cobalt excretion of 27% or less in a patient with anemia suggets that the primary cause of the anemia is not iron deficiency. A value greater than 27% in an anemic subject suggests that the anemia is caused by iron deficiency. The cobalt excretion test is a simple, sensitive and accurate method for the assessment of body iron stores. It may be particularly valuable in the epidemiological studies of iron deficiency and repeated evaluations of the body iron stores.

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The Relationship between Hair Zinc and Lead Levels and Clinical Features of Attention-Deficit Hyperactivity Disorder

  • Shin, Dong-Won;Kim, Eun-Ji;Oh, Kang-Seob;Shin, Young-Chul;Lim, Se-Won
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제25권1호
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    • pp.28-36
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    • 2014
  • Objectives : The goal of this study was to examine the association between zinc and lead level and symptoms of attention-deficit hyperactivity disorder (ADHD) among Korean children. Methods : A total of 89 clinic-referred children participated in the study (ADHD group=45, control group=44). The participants were 5-15 years old, and were mainly from urban areas of Seoul, Korea. ADHD was diagnosed using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version. We excluded children with a comorbid psychiatric disorder, medical illness requiring medication, or a prior history of taking ADHD medication. In order to evaluate the severity of ADHD symptoms, parents' Korean ADHD Rating Scale (K-ARS) was used. The ADHD diagnostic system (ADS) was used for evaluation of the severity of inattention and impulsivity. All participants completed the intelligence test and hair mineral analysis. Multiple regression analysis was used to examine the effect of hair zinc and lead levels on the K-ARS and ADS. We measured the predictive ability of the zinc and lead levels using logistic regression analysis. Results : The lead level explained the score for omission errors, commission errors, and response time SD in visual ADS in the ADHD group (adjusted $R^2$=.243, p<.01, adjusted $R^2$=.362, p<.01, and adjusted $R^2$=.275, p<.01), the score for omission errors of auditory ADS in ADHD group (adjusted $R^2$=.407, p<.01) and the entire group (adjusted $R^2$=.292, p<.01). Zinc was significantly explanatory for the K-ARS scores for the entire group (adjusted $R^2$=.248, p<.001) and the ADHD group (adjusted $R^2$=.247, p<.05). Conclusion : These findings suggest a possible role of zinc and lead in ADHD. Lead concentration in hair samples affected the ADS scores, and this was more prominent in children with ADHD. Children with ADHD had a lower zinc concentration in their hair, and the zinc concentration in hair showed negative correlation with the K-ARS score.

Clinical Usefulness of Point-of-care Test Chemistry Analyzer in Neonatal Intensive Care Unit

  • Jang, Yeong-Uk;Kim, Su-Nam;Cho, Hye-Jung;Sun, Yong-Han;Shim, So-Yeon;Son, Dong-Woo;Park, Pil-Whan
    • Neonatal Medicine
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    • 제18권2호
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    • pp.301-309
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    • 2011
  • 목적: Point-of-care test (POCT) 는 신생아 치료에 있어서 중요한 영향을 미칠 잠재력을 가지고 있다. 이 연구의 목적은 신생아 집중 치료실에서 POCT 화학 분석기기의 임상적인 유용성을 살펴보고자 하는데 있다. 방법: 신생아 집중 치료실에 입원한 신생아의 혈액 샘플을 2010년 3월부터 9월까지 POCT 화학 분석기기(Piccolo Xpress Chemistry Analyzer, Abaxis, Union City, CA, USA) 와 중앙 검사실 화학 분석기기(Chemistry analyzer 7600-110, Hitachi Ltd., Tokyo, Japan)를 이용하여 분석하였다. POCT와 중앙 검사실 기계 간의 15가지 항목에 대하여 상관 관계를 평가하였다. 또 POCT의 일치도를 알아보기 위해 세 번의 연속적인 혈액 검사를 시행하고, 세 검사간의 차이를 기록하여 평가하였다. 수행 오류가 있는 경우에는 log file을 통해서 오류의 원인을 파악하였다. 결과: 54명의 신생아에서 정확도를 위해 시행된 112쌍의 연구 중 오류가 없던 100쌍의 결과에서 두 기계 간의 높은 상관 관계를 보였다. 112쌍의 연구 도중 12개의 오류가 발생하였다. 가장 흔한 원인은 불충분한 샘플 오류였다. 일치도 검증을 위한 18명의 환아들에서 시행한 18개의 삼중 분석에서는 3-10%의 오차율이 나타났고, 이는 수용할 만한 것이었다. 54개의 분석 중 오류는 일어나지 않았다. 결론: 이 POCT는 짧은 시간 내에 소량의 전혈을 이용하여 다양한 항목을 검사할 수 있다. 비록 오류가 나타날 수 있지만, 이는 예방 가능한 것으로 사료된다. 이 POCT는 덜 침습적인 방법으로 소량의 혈액을 채취하기 때문에 신생아 집중 치료실에서 간단하고 빠른 진단에 유용하다.

Clinical image quality evaluation for panoramic radiography in Korean dental clinics

  • Choi, Bo-Ram;Choi, Da-Hye;Huh, Kyung-Hoe;Yi, Won-Jin;Heo, Min-Suk;Choi, Soon-Chul;Bae, Kwang-Hak;Lee, Sam-Sun
    • Imaging Science in Dentistry
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    • 제42권3호
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    • pp.183-190
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    • 2012
  • Purpose: The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Materials and Methods: Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the panoramic radiographs and evaluated the causes of imaging errors. Results: A total of 297 panoramic radiographs were collected from 99 dental hospitals and clinics. The mean of the scores according to the Clinical Image Quality Evaluation Chart was 79.9. In the classification of the overall image quality, 17 images were deemed 'optimal for obtaining diagnostic information,' 153 were 'adequate for diagnosis,' 109 were 'poor but diagnosable,' and nine were 'unrecognizable and too poor for diagnosis'. The results of the analysis of the causes of the errors in all the images are as follows: 139 errors in the positioning, 135 in the processing, 50 from the radiographic unit, and 13 due to anatomic abnormality. Conclusion: Panoramic radiographs taken at local dental clinics generally have a normal or higher-level image quality. Principal factors affecting image quality were positioning of the patient and image density, sharpness, and contrast. Therefore, when images are taken, the patient position should be adjusted with great care. Also, standardizing objective criteria of image density, sharpness, and contrast is required to evaluate image quality effectively.

Automatic Sputum Color Image Segmentation for Lung Cancer Diagnosis

  • Taher, Fatma;Werghi, Naoufel;Al-Ahmad, Hussain
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권1호
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    • pp.68-80
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    • 2013
  • Lung cancer is considered to be the leading cause of cancer death worldwide. A technique commonly used consists of analyzing sputum images for detecting lung cancer cells. However, the analysis of sputum is time consuming and requires highly trained personnel to avoid errors. The manual screening of sputum samples has to be improved by using image processing techniques. In this paper we present a Computer Aided Diagnosis (CAD) system for early detection and diagnosis of lung cancer based on the analysis of the sputum color image with the aim to attain a high accuracy rate and to reduce the time consumed to analyze such sputum samples. In order to form general diagnostic rules, we present a framework for segmentation and extraction of sputum cells in sputum images using respectively, a Bayesian classification method followed by region detection and feature extraction techniques to determine the shape of the nuclei inside the sputum cells. The final results will be used for a (CAD) system for early detection of lung cancer. We analyzed the performance of a Bayesian classification with respect to the color space representation and quantification. Our methods were validated via a series of experimentation conducted with a data set of 100 images. Our evaluation criteria were based on sensitivity, specificity and accuracy.

운동실조형 마비성구음장애에 적용되는 지각적, 음향학적, 생리학적 도구에 관하여 - 환자사례를 중심으로 - (Perceptual, Acoustical, and Physiological Tools in Ataxic Dysarthria Management: A Case Report)

  • 김향희
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 1996년도 2월 학술대회지
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    • pp.9-22
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    • 1996
  • Among the various dysarthric subtypes, diagnosis of ataxic dysarthria is rendered when the speech characteristics include imprecise and irregular articulatory breakdowns, marked degree of speech rate impairment, overall monopitch and monoloudness, and respiratory-articulatory incoordination. Traditionally, speech pathologists have relied only upon their ‘ears’ to describe and evaluate the dysarthric speech. A statement of percentage of correct words identified by a listener do not provide so much more than an index of severity. Within the same perceptual dimension, a carefully constructed speech intelligibility test can specify patterns of errors. The patterns can contain a diagnostic value as well as Provide strategies for remediation. The phonetically transcribed texts on single words and a standard passage, 'kail' produced by an ataxic dysarthria are presented in this report, with an emphasis of the articulatory error analysis. Furthermore,, acoustic tools [e.g., spectrography to measure formant transitions, segment durations, consonant spectra, etc.] are utilized to serve as basic measures that objectively document patients' speech intelligibility, Finally, the treatment methods [e.g., spectrography as a visual feedback, gestural reorganization using pacing method, DAF (Delayed Auditory Feedback)] to modify the dysarthric behaviors are presented.

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