• 제목/요약/키워드: receiver operating characteristic curve

검색결과 520건 처리시간 0.029초

Fibulin-3 as a Diagnostic Biomarker in Patients with Malignant Mesothelioma

  • Kaya, Halide;Demir, Melike;Taylan, Mahsuk;Sezgi, Cengizhan;Tanrikulu, Abdullah Cetin;Yilmaz, Sureyya;Bayram, Mehmet;Kaplan, Ibrahim;Senyigit, Abdurrahman
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권4호
    • /
    • pp.1403-1407
    • /
    • 2015
  • Background: New tumour biomarkers are being intensely investigated for malignant mesothelioma (MM). Fibulin-3 is produced in MM but its role remains uncertain. The aim of this study was to evaluate the validity of measuring serum fibulin-3 in the diagnosis and prognosis of MM. Materials and Methods: This prospective study was performed on 43 patients and 40 healthy controls who were admitted to our hospital between January 2012 and January 2014. Data from MM patients, including demographic and clinical features, routine laboratory data, levels of serum fibulin-3, and treatment outcomes were defined as potential prognostic factors. The receiver operating characteristic (ROC) curve for fibulin-3 was used to detect the cut-off value with highest sensitivity and specificity. Univariate survival analysis was performed using the Kaplan-Meier method in patients with MM. Afterwards, the possible factors identified with univariate analyses were entered into the cox regression analysis. Results: Our results revealed that patients with MM had significantly higher serum levels of fibulin-3 than controls. The results showed that the best cut-off point was 36.6 ng/ml with an AUC (area under the curve)=0.976, sensitivity=93.0% and specificity=90.0. In our study, the initial significant poor prognostic factors were advanced stage, high white blood cell count, high platelet count, high C-reactive protein (p<0.05 for each variable). Later, according to multivariate analysis the results showed only advanced stage as significant parameter (p=0.040). Conclusions: We determined that real use for serum fibulin-3 was not for prognosis but for diagnosis in MM. Also advanced stage was associated with poor MM prognosis.

Differentiation of Benign from Malignant Adnexal Masses by Functional 3 Tesla MRI Techniques: Diffusion-Weighted Imaging and Time-Intensity Curves of Dynamic Contrast-Enhanced MRI

  • Malek, Mahrooz;Pourashraf, Maryam;Mousavi, Azam Sadat;Rahmani, Maryam;Ahmadinejad, Nasrin;Alipour, Azam;Hashemi, Firoozeh Sadat;Shakiba, Madjid
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권8호
    • /
    • pp.3407-3412
    • /
    • 2015
  • Background: The aim of this study was to evaluate and compare the accuracy of diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) value, and time-intensity curve (TIC) type analysis derived from dynamic contrast-enhanced MR imaging (DCE-MRI) in differentiating benign from malignant adnexal masses. Materials and Methods: 47 patients with 56 adnexal masses (27 malignant and 29 benign) underwent DWI and DCE-MRI examinations, prior to surgery. DWI signal intensity, mean ADC value, and TIC type were determined for all the masses. Results: High signal intensity on DWI and type 3 TIC were helpful in differentiating benign from malignant adnexal masses (p<0.001). The mean ADC value was significantly lower in malignant adnexal masses (p<0.001). An ADC value< $1.20{\times}10^{-3}mm^2/s$ may be the optimal cutoff for differentiating between benign and malignant tumors. The negative predictive value for low signal intensity on DWI, and type 1 TIC were 100%. The pairwise comparison among the receiver operating characteristic (ROC) curves showed that the area under the curve (AUC) of TIC was significantly larger than the AUCs of DWI and ADC (p<0.001 for comparison of TIC and DWI, p<0.02 for comparison of TIC and ADC value). Conclusions: DWI, ADC value and TIC type derived from DCE-MRI are all sensitive and relatively specific methods for differentiating benign from malignant adnexal masses. By comparing these functional MR techniques, TIC was found to be more accurate than DWI and ADC.

ROC평가 방법을 이용한 CR과 DDR 흉부 영상의 비교 (The Evaluation of CR and DDR chest image using ROC analysis)

  • 박연옥;박연정;정은경;남소라;정지영;김희중
    • 한국방사선학회논문지
    • /
    • 제1권1호
    • /
    • pp.25-30
    • /
    • 2007
  • 본 연구의 목적은 ROC를 이용하여 일반 촬영기기에 따른 영상의 질을 평가해보고자 함이다. 본 연구의 수행을 위하여 CR(Computed Radiography)과 DDR(Direct Digital Radiography)을 사용하였으며 피사체로 흉부 팬텀을 사용하였다. 각 기기에서 영상을 획득한 후 ROC평가를 이용하여 영상의 질 및 기기의 특성을 평가하였다. 조사 조건으로 관전압 120kVp와 관전류량 3.2 mAs를 이용하였고 SID(Source to Image Distance)는 180cm로 설정하였다. 팬텀의 심장, 폐야, 흉추부위에 병소를 표현하였으며 각 장비에서 획득한 영상의 질 및 기기의 특성을 파악하기 위하여 방사선학 전공자 29명을 대상으로 ROC평가를 실시하였다. ROC 평가 결과 DDR의 TPF(true positive fraction)는 0.552, FPF(false positive fraction)는 0.474, CR의 TPF는 0.629, FPF는 0.405로 나타났다. 본 연구 결과 CR의 영상이 DDR의 영상보다 더 나은 영상의 질을 나타내는 것을 확인하였다. 영상의 질의 확연한 차이의 원인은 DDR의 경우 enhance board의 미 삽입으로 인한 영상 후처리의 미수행이라고 사료된다. 추후 DDR의 enhance board의 삽입 후 영상의 후처리가 가미된 DDR영상의 질에 대한 연구가 필요하며 본 연구의 결과로 인하여 영상의 후처리가 임상의 판독에 있어서 매우 중요한 요소임을 확인할 수 있었다.

  • PDF

Molybdenum 저지극을 이용한 X-ray의 미세병소 검출능력에 관한 연구 (A Study on the Detection Ability of Minute Lesions in X-ray Using the Molybdenum Target)

  • 양다래;동경래;박용순;지연상;김영근;김창복
    • Journal of Radiation Protection and Research
    • /
    • 제35권1호
    • /
    • pp.43-48
    • /
    • 2010
  • 방사선의 선질은 X선관의 target에 따라 결정된다. 유방검사의 경우 Molybdenum target을 사용하는데 22~28 kV 범위에서 평균 17.9~19.5 keV의 Mo 특성에너지를 얻어 유방의 high contrast 영상을 얻을 수 있다. 따라서 본 연구에서는 최근 대부분의 유방 검사장치에 이용되는 Mo/Mo 조합 유방장치의 미세병변 탐지능력을 측정하기 위하여 ALVIM TRM 팬텀을 이용하여 그 기초적인 실험으로 획득한 영상을 ROC(receiver operating characteristic) curve를 통해 분석하였다. 유방의 평균 피사체 두께가 40 mm로 가정하고 kV와 mAs, 그리고 두께변화에 따른 질환 검출능력을 실험한 결과, kV 변화에서는 Speck과 Fiber의 병소 검출능력이 거의 차이를 보이지 않은 것으로 나타났으며, mAs와 피사체두께 변화에서는 많은 차이를 보이는 것으로 나타났다. 즉, 유방의 피사체 평균두께인 약 40 mm에서는 관전압 변화가 병소의 검출능력에 많은 영향을 끼치지 않으므로 평균 두께의 피사체에서는 관전압을 높여서는 안된다.

Risk Factors and Preoperative Risk Scoring System for Shunt-Dependent Hydrocephalus Following Aneurysmal Subarachnoid Hemorrhage

  • Kim, Joo Hyun;Kim, Jae Hoon;Kang, Hee In;Kim, Deok Ryeong;Moon, Byung Gwan;Kim, Joo Seung
    • Journal of Korean Neurosurgical Society
    • /
    • 제62권6호
    • /
    • pp.643-648
    • /
    • 2019
  • Objective : Shunt-dependent hydrocephalus (SdHCP) is a well-known complication of aneurysmal subarachnoid hemorrhage (SAH). The risk factors for SdHCP have been widely investigated, but few risk scoring systems have been established to predict SdHCP. This study was performed to investigate the risk factors for SdHCP and devise a risk scoring system for use before aneurysm obliteration. Methods : We reviewed the data of 301 consecutive patients who underwent aneurysm obliteration following SAH from September 2007 to December 2016. The exclusion criteria for this study were previous aneurysm obliteration, previous major cerebral infarction, the presence of a cavum septum pellucidum, a midline shift of >10 mm on initial computed tomography (CT), and in-hospital mortality. We finally recruited 254 patients and analyzed the following data according to the presence or absence of SdHCP : age, sex, history of hypertension and diabetes mellitus, Hunt-Hess grade, Fisher grade, aneurysm size and location, type of treatment, bicaudate index on initial CT, intraventricular hemorrhage, cerebrospinal fluid drainage, vasospasm, and modified Rankin scale score at discharge. Results : In the multivariate analysis, acute HCP (bicaudate index of ${\geq}0.2$) (odds ratio [OR], 6.749; 95% confidence interval [CI], 2.843-16.021; p=0.000), Fisher grade of 4 (OR, 4.108; 95% CI, 1.044-16.169; p=0.043), and an age of ${\geq}50years$ (OR, 3.938; 95% CI, 1.375-11.275; p=0.011) were significantly associated with the occurrence of SdHCP. The risk scoring system using above parameters of acute HCP, Fisher grade, and age (AFA score) assigned 1 point to each (total score of 0-3 points). SdHCP occurred in 4.3% of patients with a score of 0, 8.5% with a score of 1, 25.5% with a score of 2, and 61.7% with a score of 3 (p=0.000). In the receiver operating characteristic curve analysis, the area under the curve (AUC) for the risk scoring system was 0.820 (p=0.080; 95% CI, 0.750-0.890). In the internal validation of the risk scoring system, the score reliably predicted SdHCP (AUC, 0.895; p=0.000; 95% CI, 0.847-0.943). Conclusion : Our results suggest that the herein-described AFA score is a useful tool for predicting SdHCP before aneurysm obliteration. Prospective validation is needed.

Risk factors for hospital admission in revisiting patients to the emergency department with abdominal pain

  • ;김혜진
    • 대한응급의학회지
    • /
    • 제29권6호
    • /
    • pp.679-686
    • /
    • 2018
  • Objective: The aim of this study was to identify the clinical characteristics and risk factors associated with the admission of patients in the emergency department (ED) within 30 days after discharge. Methods: A retrospective, observational study was conducted on adult patients presenting with abdominal pain to the ED of a single, urban, university hospital, between January 2014 and December 2015, who revisited the ED within 30 days after discharge. Data was collected on the emergency severity index level, time to contact doctors, physical examination, laboratory tests, use of computed tomography (CT), and patient disposition on revisitation. The primary outcome was hospital admission following an ED revisit in the 30-day period after the first visit. Results: During the study period, 19,480 patients visited the ED with the chief complaint of abdominal pain, and 13,577 were discharged. A total of 251 patients (1.29%) revisited the ED within 30 days, of which 89 were eligible for the study. The primary outcome was associated with not performing a CT scan on the initial visit and an increased C-reactive protein (CRP) value. Receiver operating characteristic curve analysis showed that a cut-off baseline CRP value of >0.35 mg/dL can predict the primary outcome with a sensitivity and specificity of 75% and 62.1%, respectively (area under the curve, 0.701; 95% confidence interval, 0.569-0.833; P=0.007). Conclusion: An increased CRP value and not performing abdominal CT were associated with a higher rate of admission following ED revisits of patients with abdominal pain. Future prospective studies on the role of abdominal CT imaging in patients presenting to the ED with abdominal pain will be needed.

Assessment of Mild Cognitive Impairment in Elderly Subjects Using a Fully Automated Brain Segmentation Software

  • Kwon, Chiheon;Kang, Koung Mi;Byun, Min Soo;Yi, Dahyun;Song, Huijin;Lee, Ji Ye;Hwang, Inpyeong;Yoo, Roh-Eul;Yun, Tae Jin;Choi, Seung Hong;Kim, Ji-hoon;Sohn, Chul-Ho;Lee, Dong Young
    • Investigative Magnetic Resonance Imaging
    • /
    • 제25권3호
    • /
    • pp.164-171
    • /
    • 2021
  • Purpose: Mild cognitive impairment (MCI) is a prodromal stage of Alzheimer's disease (AD). Brain atrophy in this disease spectrum begins in the medial temporal lobe structure, which can be recognized by magnetic resonance imaging. To overcome the unsatisfactory inter-observer reliability of visual evaluation, quantitative brain volumetry has been developed and widely investigated for the diagnosis of MCI and AD. The aim of this study was to assess the prediction accuracy of quantitative brain volumetry using a fully automated segmentation software package, NeuroQuant®, for the diagnosis of MCI. Materials and Methods: A total of 418 subjects from the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease cohort were included in our study. Each participant was allocated to either a cognitively normal old group (n = 285) or an MCI group (n = 133). Brain volumetric data were obtained from T1-weighted images using the NeuroQuant software package. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to investigate relevant brain regions and their prediction accuracies. Results: Multivariate logistic regression analysis revealed that normative percentiles of the hippocampus (P < 0.001), amygdala (P = 0.003), frontal lobe (P = 0.049), medial parietal lobe (P = 0.023), and third ventricle (P = 0.012) were independent predictive factors for MCI. In ROC analysis, normative percentiles of the hippocampus and amygdala showed fair accuracies in the diagnosis of MCI (area under the curve: 0.739 and 0.727, respectively). Conclusion: Normative percentiles of the hippocampus and amygdala provided by the fully automated segmentation software could be used for screening MCI with a reasonable post-processing time. This information might help us interpret structural MRI in patients with cognitive impairment.

외측 발목 염좌 병력에 따른 정적 하지 정렬 차이: 외측 발목 염좌의 예측인자로서 정적 하지 정렬 검사의 효용성과 한계점 (Differences in Static Lower Extremity Alignment according to the History of Lateral Ankle Sprain: Efficacy and Limitation of Static Lower Limb Alignment Measurement as a Predictor of Lateral Ankle Sprain)

  • Jeon, Hyung Gyu;Ha, Sunghe;Lee, Inje;Kang, Tae Kyu;Kim, Eun Sung;Lee, Sae Yong
    • 한국운동역학회지
    • /
    • 제31권1호
    • /
    • pp.1-15
    • /
    • 2021
  • Objective: The aim of this study was to investigate 1) the difference in static lower extremity alignment (SLEA) according to a history of lateral ankle sprain (LAS), 2) to identify SLEA factors affecting LAS, and 3) to present the cut-off value and 4) the usefulness and limitations of the SLEA measurement. Method: This case-control study recruited 88 men (age: 27.78±4.69 yrs) and 39 women (age: 24.62±4.20 yrs) subjects with and without LAS. SLEA measurement protocol included Q angle, tibiofemoral angle, genu recurvatum, rear foot (RF) angle, tibal varum and torsion, navicular drop, ankle dorsiflexion range of motion (DF ROM). Independent t-test, logistic regression and receiver operating characteristic (ROC) curve were used for statistical analysis. Results: Men with a history of LAS had significantly smaller Q angles both in standing and in supine position, while women with a history of LAS had significantly greater DF ROM in non-weight bearing (NWB; p < 0.05). Logistic regression model suggests tibial varum (OR = 0.779, p = 0.021) and WB DF ROM (OR = 1.067, p = 0.045) were associated with LAS in men. In case of women, there were no significant SLEA factors for LAS, however, ROC curve analysis revealed standing RF angle (AUC = 0.647, p = 0.028) and NWB DF ROM (AUC = 0.648, p = 0.026) could be affecting factors for LAS. Conclusion: There are differences in SLEA according to the history of LAS, furthermore, the identified items were different by sex. In case of men, tibial varum and WB DF ROM affect LAS occurrence. Standing RF angle and NWB DF ROM of women could be a predictor for LAS. However, since the sensitivity and specificity in most of the SLEA measurements are low, kinematic in dynamic tasks should be considered together for a more accurate evaluation of LAS risk.

심층학습 알고리즘을 활용한 인접면 우식 탐지 (Detection of Proximal Caries Lesions with Deep Learning Algorithm)

  • 김현태;송지수;신터전;현홍근;김정욱;장기택;김영재
    • 대한소아치과학회지
    • /
    • 제49권2호
    • /
    • pp.131-139
    • /
    • 2022
  • 이번 연구는 소아의 인접면 우식을 진단하는데 있어 사용하고 있는 구내방사선 사진에서 심층학습(deep learning) 알고리즘을 활용하여 치아우식을 진단하는 모델의 성능을 평가하고자 하였다. 제1유구치와 제2유구치 사이의 인접면이 포함된 500개의 구내방사선 사진을 대상으로 연구를 시행하였다. 치아우식을 진단하는 모델의 학습에는 Resnet50 기반의 인공신경망 모델을 사용하였다. 평가자료군에서 진단모델의 정확도, 민감도, 특이도를 구하고, ROC 곡선을 얻어 AUC 값을 바탕으로 분류 모델의 성능을 평가하였다. 학습 모델의 정확도는 0.84, 민감도는 0.74, 특이도는 0.94로 나타났으며 AUC는 0.86으로 나타났다. 인공신경망을 기반으로 하는 소아의 구내방사선 사진에서의 인접면 우식의 진단 모델은 비교적 높은 정확도를 보여주었다. 심층학습 모델은 구내방사선 사진상에서 인접면 우식을 진단하는데 있어 향후 치과의사를 보조하는 진단 도구로서 활용될 수 있을 것이다.

Influence of kilovoltage- peak and the metal artifact reduction tool in cone-beam computed tomography on the detection of bone defects around titanium-zirconia and zirconia implants

  • Fontenele, Rocharles Cavalcante;Nascimento, Eduarda Helena Leandro;Imbelloni-Vasconcelos, Ana Catarina;Martins, Luciano Augusto Cano;Pontual, Andrea dos Anjos;Ramos-Perez, Flavia Maria Moraes;Freitas, Deborah Queiroz
    • Imaging Science in Dentistry
    • /
    • 제52권3호
    • /
    • pp.267-273
    • /
    • 2022
  • Purpose: The aim of this study was to assess the influence of kilovoltage- peak (kVp) and the metal artifact reduction (MAR) tool on the detection of buccal and lingual peri-implant dehiscence in the presence of titanium-zirconia (Ti-Zr) and zirconia (Zr) implants in cone-beam computed tomography (CBCT) images. Materials and Methods: Twenty implant sites were created in the posterior region of human mandibles, including control sites (without dehiscence) and experimental sites (with dehiscence). Individually, a Ti-Zr or Zr implant was placed in each implant site. CBCT scans were performed using a Picasso Trio device, with variation in the kVp setting (70 or 90 kVp) and whether the MAR tool was used. Three oral radiologists scored the detection of dehiscence using a 5-point scale. The area under the receiver operating characteristic (ROC) curve, sensitivity, and specificity were calculated and compared by multi-way analysis of variance (α=0.05). Results: The kVp, cortical plate involved (buccal or lingual cortices), and MAR did not influence any diagnostic values (P>0.05). The material of the implant did not influence the ROC curve values(P>0.05). In contrast, the sensitivity and specificity were statistically significantly influenced by the implant material (P<0.05) with Zr implants showing higher sensitivity values and lower specificity values than Ti-Zr implants. Conclusion: The detection of peri-implant dehiscence was not influenced by kVp, use of the MAR tool, or the cortical plate. Greater sensitivity and lower specificity were shown for the detection of peri-implant dehiscence in the presence of a Zr implant.