Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
1.
Acad Radiol ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32024604

RESUMO

OBJECTIVES: The purpose of this study was to investigate regional air volume changes at the acinar scale of the lung in chronic obstructive pulmonary disease (COPD) patients using an image registration technique. MATERIALS AND METHODS: Thirty-four emphysema patients and 24 subjects with normal chest CT and pulmonary function test (PFT) results were included in this retrospective study for which informed consent was waived by the institutional review board. After lung segmentation, a mass-preserving image registration technique was used to compute relative regional air volume changes (RRAVCs) between inspiration and expiration CT scans. After determining the appropriate thresholds of RRAVCs for low ventilation areas (LVAs), they were displayed and analyzed using color maps on the background inspiration CT image, and compared with the low attenuation area (LAA) map. Correlations between quantitative CT parameters and PFTs were assessed using Pearson's correlation test, and parameters were compared between emphysema and normal-CT patients using the Student's t-test. RESULTS: LVA percentage with an RRAVC threshold of 0.5 (%LVA0.5) showed the strongest correlations with FEV1/FVC (r = -0.566), FEV1 (r = -0.534), %LAA-950insp (r = 0.712), and %LAA-856exp (r = 0.775). %LVA0.5 was significantly higher (P < 0.001) in COPD patients than normal subjects. Despite the identical appearance of emphysematous lesions on the LAA-950insp map, the RRAVC map depicted a wide range of ventilation differences between these LAA clusters. CONCLUSION: RRAVC-based %LVA0.5 correlated well with FEV1/FVC, FEV1, %LAA-950insp and %LAA-856exp. RRAVC holds the potential for providing additional acinar scale functional information for emphysematous LAAs in inspiratory CT images, providing the basis for a novel set for emphysematous phenotypes.

2.
Invest Radiol ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32058330

RESUMO

OBJECTIVES: The aim of this study was to conduct a radiopathologic evaluation of right-angled traction bronchiectasis to differentiate idiopathic pulmonary fibrosis (IPF) without honeycombing from idiopathic nonspecific interstitial pneumonia (NSIP). MATERIALS AND METHODS: The derivation cohort included 78 consecutive patients with idiopathic NSIP (n = 39) or IPF (n = 39) without honeycombing who underwent preoperative thin-section computed tomography scans at a single tertiary hospital. The validation cohort comprised 22 patients (14 IPF and 8 NSIP) from another institution. We assessed conventional computed tomography findings, right-angled traction bronchiectasis on minimum intensity projection (MinIP) images, and pathologic features associated with right-angled bronchiectasis. Right-angled traction bronchiectasis was defined as abrupt kinking of a single bronchus by over 90 degrees or an abrupt angle close to 180 degrees of branching bronchi in the background of fibrosis. In the validation cohort, we evaluated the proportion of correct IPF diagnoses and interobserver agreement of 4 radiologists before and after reviewing MinIP images. RESULTS: A probable usual interstitial pneumonia (UIP) pattern (odds ratio [OR], 6.948; 95% confidence interval [CI], 1.525-31.654; P = 0.012) and right-angled traction bronchiectasis (OR, 6.004; 95% CI, 1.980-18.209; P = 0.002) were independently associated with IPF. Patients with right-angled traction bronchiectasis were more likely to have extensive reticular opacity (OR, 1.149; 95% CI, 1.077-1.225; P < 0.001) and pathologically were more likely to have a broad extent of subpleural fibrosis (OR, 4.000; 95% CI, 1.457-10.987; P = 0.007) and relatively thick fibrosis (OR, 7.750; 95% CI, 2.504-23.991; P < 0.001). After reviewing MinIP images, the proportion of correct diagnoses increased from 40.9% to 54.5% to 50.0% to 77.3%. The mean kappa value for right-angled traction bronchiectasis was 0.489 ± 0.192. CONCLUSIONS: Right-angled traction bronchiectasis pathologically reflected a subpleural predominance of fibrosis and partly supported the radiologic differentiation of IPF without honeycombing from idiopathic NSIP.

3.
Ultrasound Med Biol ; 46(5): 1119-1132, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32059918

RESUMO

To assist radiologists in breast cancer classification in automated breast ultrasound (ABUS) imaging, we propose a computer-aided diagnosis based on a convolutional neural network (CNN) that classifies breast lesions as benign and malignant. The proposed CNN adopts a modified Inception-v3 architecture to provide efficient feature extraction in ABUS imaging. Because the ABUS images can be visualized in transverse and coronal views, the proposed CNN provides an efficient way to extract multiview features from both views. The proposed CNN was trained and evaluated on 316 breast lesions (135 malignant and 181 benign). An observer performance test was conducted to compare five human reviewers' diagnostic performance before and after referring to the predicting outcomes of the proposed CNN. Our method achieved an area under the curve (AUC) value of 0.9468 with five-folder cross-validation, for which the sensitivity and specificity were 0.886 and 0.876, respectively. Compared with conventional machine learning-based feature extraction schemes, particularly principal component analysis (PCA) and histogram of oriented gradients (HOG), our method achieved a significant improvement in classification performance. The proposed CNN achieved a >10% increased AUC value compared with PCA and HOG. During the observer performance test, the diagnostic results of all human reviewers had increased AUC values and sensitivities after referring to the classification results of the proposed CNN, and four of the five human reviewers' AUCs were significantly improved. The proposed CNN employing a multiview strategy showed promise for the diagnosis of breast cancer, and could be used as a second reviewer for increasing diagnostic reliability.

6.
Sci Rep ; 9(1): 12428, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455841

RESUMO

Non-diagnostic results can affect the diagnostic performance of percutaneous transthoracic needle biopsy (PTNB) but have not been critically meta-analyzed yet. To meta-analyze the incidence and malignancy rate of non-diagnostic results, 3-by-2 table approaches rather than the conventional 2-by-2 approaches are needed to know its impact on the diagnostic performance of PTNB. A systematic literature search identified studies evaluating the diagnostic performance of PTNB with extractable outcomes. A total of 143 studies with 35,059 biopsies were included. The pooled incidence of non-diagnostic results was 6.8% (95% CI, 6.0-7.6%; I2 = 0.91). The pooled malignancy rate of non-diagnostic results was 59.3% (95% CI, 51.7-66.8%; I2 = 0.80), and was correlated with the prevalence of malignancy (correlation coefficient, 0.66; 95% CI, 0.42-0.91). Pooled percentage decrease of sensitivity and specificity due to non-diagnostic results were 4.5% (95% CI, 3.2-5.7%; I2 = 0.64) and 10.7% (95% CI, 7.7-13.7%; I2 = 0.70), respectively, and the pooled incidence of non-diagnostic results was 4.4% (95% CI, 3.2-5.8%; I2 = 0.83) in lesions ultimately diagnosed as malignancies and 10.4% (95% CI, 7.5-13.8%; I2 = 0.74) in benign disease. In conclusion, non-diagnostic results averagely occurred in 6.8% of PTNB and more than half of the results were malignancies. The non-diagnostic results decreased specificity and sensitivity by 10.7% and 4.5%, respectively, demanding efforts to minimize the non-diagnostic results in PTNB.

7.
Korean J Radiol ; 20(7): 1236-1245, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31270987

RESUMO

OBJECTIVE: Considering the different prevalence rates of diseases such as asthma and chronic obstructive pulmonary disease in Asians relative to other races, Koreans may have unique airway structure and lung function. This study aimed to investigate unique features of airway structure and lung function based on quantitative computed tomography (QCT)-imaging metrics in the Korean Asian population (Koreans) as compared with the White American population (Whites). MATERIALS AND METHODS: QCT data of healthy non-smokers (223 Koreans vs. 70 Whites) were collected, including QCT structural variables of wall thickness (WT) and hydraulic diameter (Dh) and functional variables of air volume, total air volume change in the lung (ΔVair), percent emphysema-like lung (Emph%), and percent functional small airway disease-like lung (fSAD%). Mann-Whitney U tests were performed to compare the two groups. RESULTS: As compared with Whites, Koreans had smaller volume at inspiration, ΔVair between inspiration and expiration (p < 0.001), and Emph% at inspiration (p < 0.001). Especially, Korean females had a decrease of ΔVair in the lower lobes (p < 0.001), associated with fSAD% at the lower lobes (p < 0.05). In addition, Koreans had smaller Dh and WT of the trachea (both, p < 0.05), correlated with the forced expiratory volume in 1 second (R = 0.49, 0.39; all p < 0.001) and forced vital capacity (R = 0.55, 0.45; all p < 0.001). CONCLUSION: Koreans had unique features of airway structure and lung function as compared with Whites, and the difference was clearer in female individuals. Discriminating structural and functional features between Koreans and Whites enables exploration of inter-racial differences of pulmonary disease in terms of severity, distribution, and phenotype.

9.
Contemp Clin Trials Commun ; 9: 60-63, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29696225

RESUMO

Background and purpose: An optimal pulmonary localization technique for video-assisted thoracic surgery (VATS) of small lung nodules has not yet been established. The LOcalization of Ground-glass-opacity and pulmonary lesions for mInimal Surgery (LOGIS) registry aims to establish a multicenter database and investigate the usefulness and safety of localization techniques for small pulmonary lesions in individuals undergoing VATS. Methods/Design: The LOGIS registry is a large-scale, multicenter cohort study, aiming to enroll 825 patients at 10 institutions. Based on the inclusion and exclusion criteria, all study participants with pulmonary lesions indicated for VATS will be screened and enrolled at each site. All study participants will undergo preoperative lesion localization by the hook-wire or lipiodol localization methods according to site-specific methods. Within a few hours of marking, thoracoscopic surgery will be done under general anesthesia by experienced thoracoscopic surgeons. The primary endpoints are the success and complication rates of the two localization techniques. Secondary endpoints include procedure duration, recurrence rate, and all-cause mortality. Study participant enrollment will be completed within 2 years. Procedure success rates and incidence of complications will be analyzed based on computed tomography findings. Procedure duration, recurrence rate, and all-cause mortality will be compared between the two techniques. The study will require 5 years for completion, including 6 months of preparation, 3.5 years for recruitment, and 1 year of follow-up endpoint assessment. Discussion: The LOGIS registry, once complete, will provide objective comparative results regarding the usefulness and safety of the lipiodol and hook-wire localization techniques.

10.
Korean J Radiol ; 18(5): 773-785, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28860895

RESUMO

The role of cardiac computed tomography (CT) for evaluating the mitral valve (MV) has been limited since echocardiography is the main method of evaluation. However, recent advances in cardiac CT have enable detailed evaluation of the anatomy and geometry of the MV. We describe assessments of the anatomy and coaptation geometric parameters of normal MVs, and also review repair of diseased/damaged MV. We also discuss pre- and post-surgical imaging of MV pathology using cardiac CT and various CT images. We found that cardiac CT could be used as an alternative imaging modality to echocardiography for pre-operative MV evaluation and to predict clinical outcomes following repair.


Assuntos
Doenças das Valvas Cardíacas/diagnóstico por imagem , Valva Mitral/diagnóstico por imagem , Ecocardiografia , Doenças das Valvas Cardíacas/cirurgia , Humanos , Valva Mitral/anatomia & histologia , Tomografia Computadorizada por Raios X
12.
Korean J Radiol ; 18(4): 739-748, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670169

RESUMO

OBJECTIVE: To measure and compare the quantitative parameters of the lungs and airways in Korean never-smokers and current or former smokers ("ever-smokers"). MATERIALS AND METHODS: Never-smokers (n = 119) and ever-smokers (n = 45) who had normal spirometry and visually normal chest computed tomography (CT) results were retrospectively enrolled in this study. For quantitative CT analyses, the low attenuation area (LAA) of LAAI-950, LAAE-856, CT attenuation value at the 15th percentile, mean lung attenuation (MLA), bronchial wall thickness of inner perimeter of a 10 mm diameter airway (Pi10), total lung capacity (TLCCT), and functional residual capacity (FRCCT) were calculated based on inspiratory and expiratory CT images. To compare the results between groups according to age, sex, and smoking history, independent t test, one way ANOVA, correlation test, and simple and multiple regression analyses were performed. RESULTS: The values of attenuation parameters and volume on inspiratory and expiratory quantitative computed tomography (QCT) were significantly different between males and females (p < 0.001). The MLA and the 15th percentile value on inspiratory QCT were significantly lower in the ever-smoker group than in the never-smoker group (p < 0.05). On expiratory QCT, all lung attenuation parameters were significantly different according to the age range (p < 0.05). Pi10 in ever-smokers was significantly correlated with forced expiratory volume in 1 second/forced vital capacity (r = -0.455, p = 0.003). In simple and multivariate regression analyses, TLCCT, FRCCT, and age showed significant associations with lung attenuation (p < 0.05), and only TLCCT was significantly associated with inspiratory Pi10. CONCLUSION: In Korean subjects with normal spirometry and visually normal chest CT, there may be significant differences in QCT parameters according to sex, age, and smoking history.


Assuntos
Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Estudos Retrospectivos , Fumar
13.
Jpn J Radiol ; 35(3): 101-108, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28044222

RESUMO

PURPOSE: To describe the clinical and radiological findings of abdominopelvic involvement in scrub typhus. MATERIALS AND METHODS: Abdominopelvic computed tomography (CT) of 78 patients with scrub typhus were evaluated by two readers. The presence of gallbladder wall thickening, arterial inhomogeneous enhancement of the liver, periportal edema, splenic infarction, hepatomegaly, splenomegaly, ascites, pleural effusion, and sites of lymphadenopathy were evaluated. Patients were divided into four clinical subgroups according to laboratory findings. Association between imaging findings and subgroups was analyzed by Chi squared test or Fisher's exact test. RESULTS: The most common CT finding was hepatomegaly (74.4%), followed by splenomegaly (66.7%). The majority of patients had at least three areas of abdominopelvic lymphadenopathy (71.8%). Pelvic lymphadenopathy was most commonly seen when eschar was found in the ipsilateral lower extremity (left, n = 5/7; right, n = 8/13). Significant association between hepatic dysfunction and perigastric lymphadenopathy was documented (p = 0.03). CONCLUSION: Scrub typhus has a spectrum of variable clinical and radiological findings mimicking those of acute hepatitis. Diffuse abdominopelvic lymphadenopathy involving the retroperitoneum and pelvic area may aid in early diagnosis of scrub typhus. Perigastric lymphadenopathy could be a sign of severe scrub typhus combined with hepatic dysfunction.


Assuntos
Tifo por Ácaros/diagnóstico por imagem , Tifo por Ácaros/patologia , Abdome/diagnóstico por imagem , Abdome/microbiologia , Abdome/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Pelve/diagnóstico por imagem , Pelve/microbiologia , Pelve/patologia , Estudos Retrospectivos , Tifo por Ácaros/microbiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
14.
J Magn Reson Imaging ; 45(5): 1494-1501, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27619627

RESUMO

PURPOSE: To compare the apparent diffusion coefficient (ADC) of upper abdominal organs acquired at different time points, and to investigate the usefulness of normalization. MATERIALS AND METHODS: We retrospectively evaluated 58 patients who underwent three rounds of magnetic resonance (MR) imaging including diffusion-weighted imaging of the upper abdomen. MR examinations were performed using three different 3.0 Tesla (T) and one 1.5T systems, with variable b value combinations and respiratory motion compensation techniques. The ADC values of the upper abdominal organs from three different time points were analyzed, using the ADC values of the paraspinal muscle (ADCpsm ) and spleen (ADCspleen ) for normalization. Intraclass correlation coefficients (ICC) and comparison of dependent ICCs were used for statistical analysis. RESULTS: The ICCs of the original ADC and ADCpsm showed fair to substantial agreement, while ADCspleen showed substantial to almost perfect agreement. The ICC of ADCspleen of all anatomical regions showed less variability compared with that of the original ADC (P < 0.005). CONCLUSION: Normalized ADC using the spleen as a reference organ significantly decreased variability in measurement of the upper abdominal organs in different MR systems at different time points and could be regarded as an imaging biomarker for future multicenter, longitudinal studies. LEVEL OF EVIDENCE: 5 J. MAGN. RESON. IMAGING 2017;45:1494-1501.


Assuntos
Abdome/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Hepatopatias/diagnóstico por imagem , Idoso , Doença Crônica , Feminino , Hepatite Crônica/diagnóstico por imagem , Humanos , Cirrose Hepática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Movimento , Valores de Referência , Respiração , Estudos Retrospectivos
15.
PLoS One ; 11(9): e0162231, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27611866

RESUMO

OBJECTIVE: To differentiate smoking-related interstitial fibrosis (SRIF) from usual interstitial pneumonia (UIP) with emphysema on CT in combined pulmonary fibrosis and emphysema (CPFE) patients. MATERIALS AND METHODS: This study was approved by the institutional review board and informed consent was waived. We included 65 patients who underwent lung biopsy under the suspicion of UIP pattern on HRCT, and after radiologic-pathologic correlation, they were divided into three groups: UIP without emphysema (n = 30), UIP with emphysema (n = 26), and SRIF (n = 9). The quantitative extent of emphysema in the entire lung was visually assessed and fibrotic patterns were qualitatively analyzed based on six characteristics (asymmetry, juxta-subpleural sparing, emphysema beside the honeycombing area, absence of ground grass attenuation/reticulation in honeycombing area, inhomogeneous honeycombing, and absence of honeycombing in the upper lobes). Kaplan-Meier analysis was used for survival analysis, and logistic regression with a receiver operating characteristic curve was used to predict the possibility of SRIF. RESULTS: In qualitative analysis of fibrotic patterns, SRIF tended to exhibit more than three of six fibrotic features, whereas UIP with emphysema demonstrated about two of these characteristics (p = 0.035). In addition, SRIF had a higher extent of emphysema than UIP with emphysema when they have same amount of fibrosis (p = 0.014). In patients with SRIF, 5-year survival rate was 85.7%, while it was 40.7% in UIP with emphysema patients (p = 0.035). CONCLUSION: Fibrotic CT patterns and survival rate differed between SRIF and UIP with emphysema among CPFE patients, which explains the variable prognosis of CPFE.


Assuntos
Doenças Pulmonares Intersticiais/diagnóstico , Enfisema Pulmonar/diagnóstico , Fibrose Pulmonar/diagnóstico , Fumar/efeitos adversos , Tomografia Computadorizada por Raios X , Idoso , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/patologia , Masculino , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/patologia , Fibrose Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , Estudos Retrospectivos
16.
Thorac Cancer ; 7(4): 503-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27385996

RESUMO

Melanoma is a cutaneous malignant neoplasm of melanocytes. Primary malignant melanoma (MM) of the lung is very rare. Although previous reports have described the radiologic features of pulmonary MM, its rarity means that many factors are unknown. Thus, radiologic diagnosis is very difficult. Furthermore, there is little information regarding diagnostic application and/or the usefulness of [(18)F]-fluorine-2-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (FDG-PET-CT) for primary pulmonary MM. A 69-year-old patient with a productive cough lasting three weeks was admitted to our hospital. Chest CT showed a large single mass with a multi-lobulated margin and homogeneous enhancement in the right upper lobe, which was subsequently diagnosed as a primary pulmonary MM with multiple metastases. On PET-CT images, the pulmonary mass and multiple bone lesions showed very increased uptakes of FDG. Considering that pulmonary metastasis from a mucocutaneous melanoma is the main differential diagnosis of primary pulmonary MM, systemic assessment of the whole body is more important than for other types of lung malignancies. This report introduces PET-CT as a useful diagnostic modality for pulmonary MM, especially in cases of distant multiple metastases.

17.
Respirology ; 21(7): 1330-2, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27325583

RESUMO

Determinants of abnormal lung function among subjects with normal chest radiography have not been widely evaluated. We investigated 12 109 participants with normal chest radiographs from the Korean National Health and Nutrition Examination Survey. Factors associated with abnormal pulmonary function were male gender, age ≥50, smoking history and a clinical history of cough or sputum production. Pulmonary function tests should be considered in population-based screening, especially in men over 50 years old with a smoking history.


Assuntos
Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Tosse/fisiopatologia , Feminino , Humanos , Masculino , Radiografia Pulmonar de Massa , Pessoa de Meia-Idade , Inquéritos Nutricionais , República da Coreia , Testes de Função Respiratória , Fatores de Risco , Fumar
18.
Korean J Radiol ; 17(3): 330-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27134522

RESUMO

OBJECTIVE: This multi-center, randomized, double-blind, phase 3 trial was conducted to compare the safety and efficacy of contrast agents iohexol-380 and iohexol-350 for coronary CT angiography in healthy subjects. MATERIALS AND METHODS: Volunteers were randomized to receive 420 mgI/kg of either iohexol-350 or iohexol-380 using a flow rate of 4 mL/sec. All adverse events were recorded. Two blinded readers independently reviewed the CT images and conflicting results were resolved by a third reader. Luminal attenuations (ascending aorta, left main coronary artery, and left ventricle) in Hounsfield units (HUs) and image quality on a 4-point scale were calculated. RESULTS: A total of 225 subjects were given contrast media (115 with iohexol-380 and 110 with iohexol-350). There was no difference in number of adverse drug reactions between groups: 75 events in 56 (48.7%) of 115 subjects in the iohexol-380 group vs. 74 events in 51 (46.4%) of 110 subjects in the iohexol-350 group (p = 0.690). No severe adverse drug reactions were recorded. Neither group showed an increase in serum creatinine. Significant differences in mean density between the groups was found in the ascending aorta: 375.8 ± 71.4 HU with iohexol-380 vs. 356.3 ± 61.5 HU with iohexol-350 (p = 0.030). No significant differences in image quality scores between both groups were observed for all three anatomic evaluations (all, p > 0.05). CONCLUSION: Iohexol-380 provides improved enhancement of the ascending aorta and similar attenuation of the coronary arteries without any increase in adverse drug reactions, as compared with iohexol-350 using an identical amount of total iodine.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/química , Vasos Coronários/diagnóstico por imagem , Iohexol/química , Adulto , Idoso , Aorta/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Creatinina/sangue , Método Duplo-Cego , Eletrocardiografia , Feminino , Gastroenteropatias/etiologia , Voluntários Saudáveis , Humanos , Interpretação de Imagem Assistida por Computador , Iohexol/efeitos adversos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Dermatopatias/etiologia , Adulto Jovem
19.
Korean J Radiol ; 17(2): 209-17, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26957905

RESUMO

OBJECTIVE: To compare the apparent diffusion coefficient (ADC) values of upper abdominal organs with 2 different 3.0 tesla MR systems and to investigate the usefulness of normalization using the spleen. MATERIALS AND METHODS: Forty-one patients were enrolled in this prospective study, of which, 35 patients (M:F, 27:8; mean age ± standard deviation, 62.3 ± 12.3 years) were finally analyzed. In addition to the routine liver MR protocol, single-shot spin-echo echo-planar diffusion-weighted imaging using b values of 0, 50, 400, and 800 s/mm(2) in 2 different MR systems was performed. ADC values of the liver, spleen, pancreas, kidney and liver lesion (if present) were measured and analyzed. ADC values of the spleen were used for normalization. The Pearson correlation, Spearman correlation, paired sample t test, Wilcoxon signed rank test and Bland-Altman method were used for statistical analysis. RESULTS: For all anatomical regions and liver lesions, both non-normalized and normalized ADC values from 2 different MR systems showed significant correlations (r = 0.5196-0.8488). Non-normalized ADC values of both MR systems differed significantly in all anatomical regions and liver lesions (p < 0.001). However, the normalized ADC of all anatomical regions and liver lesions did not differ significantly (p = 0.065-0.661), with significantly lower coefficient of variance than that of non-normalized ADC (p < 0.009). CONCLUSION: Normalization of the abdominal ADC values using the spleen as a reference organ reduces differences between different MR systems, and could facilitate consistent use of ADC as an imaging biomarker for multi-center or longitudinal studies.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Pâncreas/diagnóstico por imagem , Baço/diagnóstico por imagem , Idoso , Imagem Ecoplanar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA