Assuntos
Prática Clínica Baseada em Evidências/métodos , Hepatopatias/mortalidade , Atenção Primária à Saúde/métodos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/mortalidade , Efeitos Psicossociais da Doença , Gerenciamento Clínico , Técnicas de Imagem por Elasticidade/normas , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Testes Hematológicos/normas , Testes Hematológicos/estatística & dados numéricos , Humanos , Hepatopatias/diagnóstico , Hepatopatias/epidemiologia , Hepatopatias/terapia , Pessoa de Meia-Idade , Morbidade/tendências , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/mortalidade , Obesidade/epidemiologia , Obesidade/mortalidade , Recompensa , Reino Unido/epidemiologiaRESUMO
Non-alcoholic fatty liver disease (NAFLD) is expected to increase in prevalence because of the ongoing epidemics of obesity and diabetes, and it has become a major cause of chronic liver disease worldwide. Liver fibrosis is associated with long-term outcomes in patients with NAFLD. Liver biopsy is recommended as the gold standard method for the staging of liver fibrosis. However, it has several problems. Therefore, simple and noninvasive methods for the diagnosis and staging of liver fibrosis are urgently needed in place of biopsy. This review discusses recent studies of elastography techniques (vibration-controlled transient elastography, point shear wave elastography, two-dimensional shear wave elastography, and magnetic resonance elastography) that can be used for the assessment of liver fibrosis in patients with NAFLD.
Assuntos
Técnicas de Imagem por Elasticidade , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Gerenciamento Clínico , Suscetibilidade a Doenças , Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , HumanosRESUMO
Inadequate margins in breast-conserving surgery (BCS) are associated with an increased likelihood of local recurrence of breast cancer. Currently, approximately 20% of BCS patients require repeat surgery due to inadequate margins at the initial operation. Implementation of an accurate, intraoperative margin assessment tool may reduce this re-excision rate. This study determined, for the first time, the diagnostic accuracy of quantitative micro-elastography (QME), an optical coherence tomography (OCT)-based elastography technique that produces images of tissue microscale elasticity, for detecting tumor within 1 mm of the margins of BCS specimens. Simultaneous OCT and QME were performed on the margins of intact, freshly excised specimens from 83 patients undergoing BCS and on dissected specimens from 7 patients undergoing mastectomy. The resulting three-dimensional images (45 × 45 × 1 mm) were coregistered with postoperative histology to determine tissue types present in each scan. Data from 12 BCS patients and the 7 mastectomy patients served to build a set of images for reader training. One hundred and fifty-four subimages (10 × 10 × 1 mm) from the remaining 71 BCS patients were included in a blinded reader study, which resulted in 69.0% sensitivity and 79.0% specificity using OCT images, versus 92.9% sensitivity and 96.4% specificity using elasticity images. The quantitative nature of QME also facilitated development of an automated reader, which resulted in 100.0% sensitivity and 97.7% specificity. These results demonstrate high accuracy of QME for detecting tumor within 1 mm of the margin and the potential for this technique to improve outcomes in BCS. SIGNIFICANCE: An optical imaging technology probes breast tissue elasticity to provide accurate assessment of tumor margin involvement in breast-conserving surgery.
Assuntos
Adenocarcinoma Mucinoso/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Margens de Excisão , Mastectomia Segmentar/métodos , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/cirurgia , Adulto , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Técnicas de Imagem por Elasticidade/normas , Feminino , Humanos , Mastectomia Segmentar/normas , Pessoa de Meia-Idade , Reoperação , Tomografia de Coerência ÓpticaRESUMO
BACKGROUND: Assessment of liver stiffness provides important diagnostic and prognostic information in patients with chronic liver disease. AIMS: To investigate whether the use of quality criteria (i) improves the concordance between transient elastography (TE) and a novel point shear wave elastography technique (ElastPQ®) and (ii) impacts on the performance of ElastPQ® for liver fibrosis staging using TE as the reference standard. METHODS: In this multicenter retrospective study, data of patients undergoing liver stiffness measurements (LSM) in five European centers were collected. TE was performed with FibroScan® (Echosens, France) and ElastPQ® with EPIQ® or Affiniti® systems (Philips, The Netherlands). The agreement between TE and ElastPQ® LSMs was assessed with Lin's concordance correlation coefficient (CCC). Diagnostic performance of ElastPQ® was assessed by the area under receiver operating characteristic (AUROC) curves. RESULTS: Overall, 664 patients were included: mean age: 54.8(13.5) years, main etiologies: viral hepatitis (83.1%) and NAFLD (7.5%). CCC increased significantly when LSMs with ElastPQ® were obtained with IQR/Mâ¯≤â¯30% (pâ¯<â¯0.001). The diagnostic performance of ElastPQ® for fibrosis staging also increased if LSM values were obtained with IQR/Mâ¯≤â¯30%. CONCLUSION: Quality criteria should be followed when using ElastPQ® for LSM, since the concordance with TE fibrosis staging was better at an ElastPQ® IQR/Mâ¯≤â¯30.
Assuntos
Técnicas de Imagem por Elasticidade/normas , Fidelidade a Diretrizes , Cirrose Hepática/diagnóstico por imagem , Fígado/patologia , Adulto , Idoso , Área Sob a Curva , Europa (Continente) , Feminino , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
OBJECTIVE: To assess differences in biceps brachii muscle (BBM) stiffness as evaluated by ultrasound shear wave elastography (SWE). METHODS: The passive stiffness of the BBM was quantified with shear wave velocity (SWV) measurements obtained from 10 healthy volunteers (5 men and 5 women, mean age 50years, age range 42-63 years) with the elbow at full extension and 30° flexion in this IRB-approved study. Potential differences between two depths within the muscle, two elbow positions, the two arms, and sexes were assessed by using two-tailed t-test. The reproducibility of SWV measurements was tested by using intraclass correlation coefficient (ICC). RESULTS: Significantly higher passive BBM stiffness was found at full elbow extension compared to 30° of flexion (p≤0.00006 for both arms). Significantly higher passive stiffness in women was seen for the right arm (p=0.04 for both elbow positions). Good correlation of shear wave velocity measured at the different depths. The ICC for interobserver and intraobserver variation was high. CONCLUSIONS: SWE is a reliable quantitative tool for assessing BBM stiffness, with differences in stiffness based on elbow position demonstrated and based on sex suggested.
Assuntos
Técnicas de Imagem por Elasticidade/métodos , Articulação do Cotovelo/diagnóstico por imagem , Cotovelo/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Amplitude de Movimento Articular , Adulto , Técnicas de Imagem por Elasticidade/normas , Cotovelo/patologia , Articulação do Cotovelo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Fatores Sexuais , Ultrassonografia/métodosRESUMO
Shear wave elastography is increasingly being used to non-invasively stage liver fibrosis by measuring shear wave speed (SWS). This study quantitatively investigates intrinsic variations among SWS measurements obtained from heterogeneous media such as fibrotic livers. More specifically, it aims to demonstrate that intrinsic variations in SWS measurements, in general, follow a non-Gaussian distribution and are related to the heterogeneous nature of the medium being measured. Using the principle of maximum entropy (ME), our primary objective is to derive a probability density function (PDF) of the SWS distribution in conjunction with a lossless stochastic tissue model. Our secondary objective is to evaluate the performance of the proposed PDF using Monte Carlo (MC)-simulated shear wave (SW) data against three other commonly used PDFs. Based on statistical evaluation criteria, initial results showed that the derived PDF fits better to MC-simulated SWS data than the other three PDFs. It was also found that SW fronts stabilized after a short (compared with the SW wavelength) travel distance in lossless media. Furthermore, in lossless media, the distance required to stabilize the SW propagation was not correlated to the SW wavelength at the low frequencies investigated (i.e. 50, 100 and 150 Hz). Examination of the MC simulation data suggests that elastic (shear) wave scattering became more pronounced when the volume fraction of hard inclusions increased from 10 to 30%. In conclusion, using the principle of ME, we theoretically demonstrated for the first time that SWS measurements in this model follow a non-Gaussian distribution. Preliminary data indicated that the proposed PDF can quantitatively represent intrinsic variations in SWS measurements simulated using a two-phase random medium model. The advantages of the proposed PDF are its physically meaningful parameters and solid theoretical basis.
Assuntos
Técnicas de Imagem por Elasticidade/normas , Cirrose Hepática/diagnóstico por imagem , Análise de Variância , Técnicas de Imagem por Elasticidade/métodos , Humanos , Método de Monte CarloRESUMO
BACKGROUND: The study aimed to improve breast cancer diagnosis with new ultrasound (US) modalities. We examined whether real-time elastography (RTE) complements the diagnostic performance of US. METHODS: The Ethical Committee approved the study. Patients provided written informed consent and received a whole breast workup. Breast lesions were evaluated by US and RTE. Lesions were assessed by BI-RADS, Tsukuba score (TS) and strain ratio (SR). RESULTS: The study included 164 breast lesions of which 101 were benign and 63 malignant. Women with benign lesions were predominantly premenopausal with sonographic dense breast tissue. Women with breast cancer were mostly postmenopausal, with a low sonographic density. Benign lesions had a mean TS of 2.05, which was significantly lower than the mean TS of 3.25 for malignant lesions. The SR for benign lesions (SR 1.83) was significantly smaller than for breast cancer (SR 4.83). Sensitivity and specificity was 95 and 81% for BI-RADS, 39 and 94% for TS, and 57 and 83% for SR, with a cutoff at 2.5. The combination of BI-RADS, TS and SR yielded a sensitivity of 95% and a specificity of 85%. CONCLUSION: Besides morphologic features revealed by US, elastic properties of breast lesions obtained by RTE can be exploited for diagnostic breast imaging.
Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/normas , Ultrassonografia Mamária/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND AND AIMS: Noninvasive assessment of liver stiffness has been increasingly used to evaluate fibrosis instead of liver biopsy, especially in patients with chronic viral hepatitis. The aim of this study was to assess the performance in staging liver fibrosis of the updated ElastPQ® technique (EPIQ7 ultrasound system, Philips Healthcare, Bothell, WA, USA) in the "real life" setting by using the FibroScan as the reference standard and to understand whether the use of the quality criteria improves the performance of the technique. METHODS: This was a cross-sectional study: 278 patients affected by chronic hepatitis C referred for liver stiffness measurement with the FibroScan® 502 Touch device (Echosens, Paris, France) underwent measurements also with the ElastPQ® technique. For the assessment of significant fibrosis (F>/=2), advanced fibrosis (F>/=3) and cirrhosis (F=4), respectively, we used the cutoffs of 7.0, 9.5 and 12.0 kPa. The diagnostic performance of ElastPQ® was assessed using the area under the ROC (AUROC) curve analysis and was evaluated overall and for cases with (a) 10 measurements and IQR/M=30%, (b) 5 measurements and IQR/M =30%, (c) 10 measurements and IQR/M>30%, (d) 5 measurements and IQR/M>30%. RESULTS: The optimal cutoffs of ElastPQ® for significant fibrosis, advanced fibrosis and cirrhosis were 6.43, 9.54 and 11.34 kPa, respectively. For measurements with an IQR/M=30%, there was no statistically significant decrease in sensitivity between 10 and 5 measurements (p=0.26, p=0.09, p=0.71, for F>/=2, F>/=3, and F=4, respectively). CONCLUSION: The ElastPQ® technique is reliable and accurate for staging liver fibrosis. The number of measurements does not affect the performance.
Assuntos
Técnicas de Imagem por Elasticidade , Hepatite C Crônica/virologia , Cirrose Hepática/diagnóstico por imagem , Idoso , Área Sob a Curva , Estudos Transversais , Técnicas de Imagem por Elasticidade/normas , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Humanos , Itália , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Padrões de Referência , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Liver fibrosis is a sign of advanced liver disease and is often an indication for treatment. The current standard for diagnosing liver fibrosis and steatosis is biopsy, but noninvasive alternatives are available; one of the most common is transient elastography (FibroScan). OBJECTIVES: The objective of this analysis was to assess the diagnostic accuracy and clinical utility of transient elastography alone for liver fibrosis and with controlled attenuation parameter (CAP) for steatosis in patients with hepatitis C virus, hepatitis B virus, nonalcoholic fatty liver disease, alcoholic liver disease, or cholestatic diseases. The analysis also aimed to compare the diagnostic accuracy of transient elastography with two alternative noninvasive technologies: FibroTest and acoustic force radiation impulse (ARFI). DATA SOURCES: Ovid MEDLINE, Ovid MEDLINE In-Process, Ovid Embase, and all EBM databases were searched for all studies published prior to October 2, 2014. REVIEW METHODS: An overview of reviews was conducted using a systematic search and assessment approach. The results of the included systematic reviews were summarized, analyzed, and reported for outcomes related to diagnostic accuracy and clinical utility as a measure of impact on diagnoses, therapeutic decisions, and patient outcomes. RESULTS: Fourteen systematic reviews were included, summarizing more than 150 studies. The reviews demonstrated that transient elastography (with or without CAP) has good diagnostic accuracy compared to biopsy for the assessment of liver fibrosis and steatosis. Acoustic force radiation impulse and FibroTest were not superior to transient elastography. LIMITATIONS: None of the included systematic reviews reported on the clinical utility of transient elastography. CONCLUSIONS: Transient elastography (with or without CAP) offers a noninvasive alternative to biopsy for the assessment of liver fibrosis and steatosis, given its comparable diagnostic accuracy.
Assuntos
Técnicas de Imagem por Elasticidade/métodos , Fígado Gorduroso/diagnóstico , Cirrose Hepática/diagnóstico , Técnicas de Imagem por Elasticidade/normas , Medicina Baseada em Evidências , HumanosRESUMO
The aim of the present study was to investigate the combination of certain serological markers (Forns' index; FI), FibroScan® and acoustic radiation force impulse elastography (ARFI) in the assessment of liver fibrosis in patients with hepatitis B, and to explore the impact of inflammatory activity and steatosis on the accuracy of these diagnostic methods. Eightyone patients who had been diagnosed with hepatitis B were recruited and the stage of fibrosis was determined by biopsy. The diagnostic accuracy of FI, FibroScan and ARFI, as well as that of the combination of these methods, was evaluated based on the conformity of the results from these tests with those of biopsies. The effect of concomitant inflammation on diagnostic accuracy was also investigated by dividing the patients into two groups based on the grade of inflammation (G<2 and G≥2). The overall univariate correlation between steatosis and the diagnostic value of the three methods was also evaluated. There was a significant association between the stage of fibrosis and the results obtained using ARFI and FibroScan (KruskalWallis; P<0.001 for all patients), and FI (t-test, P<0.001 for all patients). The combination of FI with ARFI/FibroScan increased the predictive accuracy with a fibrosis stage of S≥2 or cirrhosis. There was a significant correlation between the grade of inflammation and the results obtained using ARFI and FibroScan (KruskalWallis, P<0.001 for all patients), and FI (t-test; P<0.001 for all patients). No significant correlation was detected between the measurements obtained using ARFI, FibroScan and FI, and steatosis (r=0.100, P=0.407; r=0.170, P=0.163; and r=0.154, P=0.216, respectively). ARFI was shown to be as effective in the diagnosis of liver fibrosis as FibroScan or FI, and the combination of ARFI or FibroScan with FI may improve the accuracy of diagnosis. The presence of inflammatory activity, but not that of steatosis, may affect the diagnostic accuracy of these methods.
Assuntos
Técnicas de Imagem por Elasticidade , Fígado Gorduroso/patologia , Hepatite B Crônica/complicações , Inflamação/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Adulto , Biomarcadores , Biópsia , Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Feminino , Hepatite B Crônica/diagnóstico , Humanos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaRESUMO
OBJECTIVES: To evaluate reproducibility of measurements of spleen stiffness (SS) and liver stiffness (LS) at several sites by using point shear wave elastography (pSWE) and to investigate any training effect. METHODS: Healthy volunteers were consecutively enrolled. Measurements of SS and LS were performed by an expert (observer 1) and a novice (observer 2) at three different sites of liver and spleen. To assess the effect of training the study was conducted in two periods (period 1 and period 2). Concordance correlation coefficient was used to assess intra-observer and inter-observer reproducibility. RESULTS: A total of 92 subjects (67 men and 25 women) were enrolled in the study. Both intra-observer and inter-observer agreement were higher for the liver than for the spleen. Overall, the highest intra-observer and inter-observer agreement were obtained for the assessment of LS through intercostal space, and for measurements at this site there was a significantly better performance of observer 2 after the training period. For both observers, training improved the repeatability of SS measurements at all sites. A good intra-observer agreement was obtained only for measurements at the spleen lower pole. CONCLUSIONS: The results of this study show that a learning curve in pSWE acquisition should be taken into account both for SS and LS measurements. KEY POINTS: Reproducibility of SS measurements depends on the expertise of the operator. To achieve good reproducibility between measurements a training period is required. A learning curve in pSWE acquisition should be taken into account. SS measurements are less reproducible than LS measurements.
Assuntos
Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Fígado/diagnóstico por imagem , Baço/diagnóstico por imagem , Adulto , Estudos Transversais , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto JovemRESUMO
PURPOSE: Spleen elastography is a promising method for the characterization of portal hypertension in cirrhotic individuals. However, standardized examination procedures for spleen stiffness measurement have not been defined yet. We analyzed the distribution characteristics of spleen shear-wave velocity (ARFI) and assessed the influence of the respiratory position on spleen stiffness measured by ARFI. MATERIALS AND METHODS: 25 healthy probands and 25 patients with Child A liver cirrhosis were prospectively characterized with conventional ultrasound, transient elastography, liver ARFI, and underwent spleen ARFI in two respiratory positions: breath hold after expiration (exp) and deep inspiration (insp). For each position 20 single measurements were performed. The distribution of spleen ARFI values was analyzed for normality and the appropriate number of measurements for spleen stiffness estimation was investigated. RESULTS: Spleen ARFI results were normally distributed in >â95â% of cases. Performing 20 instead of 10 single measurements resulted in <â5â% deviation from the mean value after 20 measurements in the majority of cases. Cirrhotic patients had a higher spleen stiffness compared to healthy probands (exp: 3.25â±â0.58 vs. 2.46â±â0.35âm/s; pâ<â0.001). Deep inspiration caused an overall increase in spleen stiffness in both groups: probands 2.46â± 0.35âm/s (exp) vs. 2.66â±â0.36âm/s (insp), pâ=â0.01; cirrhotics 3.25â±â0.58âm/s (exp) vs. 3.46â±â0.38âm/s (insp), pâ=â0.03. However, cases with high spleen stiffness values (exp) show decreasing ARFI values in deep inspiration. CONCLUSION: ARFI values of the spleen are normally distributed and the mean of 10 valid measurements can be used as a representative value. Deep inspiration significantly modulates spleen stiffness. Therefore, the respiratory position needs careful standardization.
Assuntos
Suspensão da Respiração , Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Hipertensão Portal/diagnóstico por imagem , Inalação , Baço/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Fígado/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente , Valores de Referência , Sensibilidade e Especificidade , Resistência ao CisalhamentoRESUMO
UNLABELLED: BACKGROUND AND RATIONALE FOR THE STUDY: Limited studies have aimed to define the cut-offs of XL probe (XL cut-offs) for different stages of liver fibrosis, whereas those of M probe (M cut-offs) may not be applicable to XL probe. We aimed to derive appropriate XL cut-offs in overweight patients. Patients with liver stiffness measurement (LSM) by both probes were recruited. XL cut-offs probe for corresponding M cut-offs were derived from an exploratory cohort, and subsequently validated in a subgroup patients also underwent liver biopsy. The diagnostic accuracy of XL cut-offs to diagnose advanced fibrosis was evaluated. RESULTS: Total 517 patients (63% male, mean age 58) who had reliable LSM by both probes were included in the exploratory cohort. There was a strong correlation between the LSM by M probe (LSM-M) and LSM by XL probe (LSM-XL) (r² = 0.89, p < 0.001). A decision tree using LSM-XL was learnt to predict the 3 categories of LSM-M (< 6.0kPa, 6.0-11.9kPa and ≥ 12.0kPa), and XL cut-offs at 4.8kPa and 10.7kPa were identified. These cut-offs were subsequently validated in a cohort of 147 patients who underwent liver biopsy. The overall accuracy was 89% among 62 patients whose LSM-XL < 4.8kPa or ≥ 10.7kPa. These cut-offs would have avoided under-staging of fibrosis among patients with body mass index (BMI) > 25-30 kg/m2 but not > 30 kg/m2. CONCLUSIONS: XL cut-offs at 4.8kPa and 10.7kPa were the best estimates of 6.0kPa and 12.0kPa of M probe for patients with BMI > 25-30 kg/m2. Patients with BMI > 30 kg/m² might use M probe cut-offs for XL probe.
Assuntos
Técnicas de Imagem por Elasticidade/instrumentação , Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Adulto , Idoso , Algoritmos , Biópsia , Calibragem , Técnicas de Apoio para a Decisão , Árvores de Decisões , Módulo de Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/normas , Desenho de Equipamento , Feminino , França , Hong Kong , Humanos , Modelos Lineares , Fígado/patologia , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
El pronóstico de la enfermedad crónica hepática depende de la extensión y la progresión de la fibrosis hepática. Actualmente la biopsia hepática es la técnica de elección para determinar el grado de fibrosis, pero es una prueba invasiva, no exenta de complicaciones. Por ello, el desarrollo de marcadores no invasivos de fibrosis hepática se convirtió en una necesidad indiscutible. Se propuso la elastografìa por transición (Fibroscan®) para valorar la fibrosis hepática en pacientes con enfermedad crónica hepática, mediante la medición de la rigidez hepática. Nuestro objetivo fue evaluar la efectividad, la objetividad y la seguridad de esta técnica. Se estudiaron 68 pacientes a los que se les realizó una biopsia hepática en los 18 meses previos al estudio. Todos los procedimientos de elastografia y biopsia hepática fueron analizados por un mismo profesional (DA y MA, respectivamente). Para la valoración de la biopsia hepática se utilizó la escala METAVIR. El valor medio de rigidez en pacientes sin fibrosis o con fibrosis leve (F0-F1) y en los pacientes con fibrosis avanzada o cirrosis (F3-F4) fue 6.8 ± 3.0 kPa y 21.0 ± 15.1 kPa, respectivamente (con diferencia significativa, p < 0.01). Las áreas debajo de la curva ROC definieron los niveles de corte en cada grupo. Con independencia del diagnóstico etiológico de enfermedad hepática, hallamos una correlación positiva, en todos los pacientes, entre rigidez hepática medida por elastografìa y grado de fibrosis hepática en la biopsia. En conclusión, podemos considerar que el Fibroscan® es un método no invasivo, seguro, fácil y rápido, que lo convierte en la alternativa a la biopsia para identificar fibrosis significativa o cirrosis.
The prognosis and management of chronic liver disease largely depends on the extent and progression of liver fibrosis. Unfortunately, liver biopsy, an invasive and painful technique with several limitations, continues to be the gold standard for the staging and grading of fibrosis. Therefore, accurate noninvasive tests for liver injury are urgently needed. During the last years, transient elastography (Fibroscan®) has been proposed for the assessment of hepatic fibrosis in patients with chronic liver disease, by measuring liver stiffness. The aim of this study was to evaluate the effectiveness, objectivity and safety of this technique. We included 68 patients who underwent a liver biopsy in the last 18 months with a wide spectrum of chronic liver diseases. All procedures as well as the liver biopsies according to the METAVIR scoring system were analyzed by the same sonographer and the same specialist in pathology, respectively. Median value of stiffness with none or mild fibrosis (F0 and FI), and severe fibrosis or cirrhosis (F3 and F4) was 6.8 ± 3.0 kPa and 21.0 ± 15.1 kPa, respectively, with a significant difference between them (p < 0.01). The areas under the receiver operating characteristic curves showed the optimal liver stiffness cut-off values for each group. We found also a positive correlation between liver stiffness found by transient elastography and fibrosis stage on biopsy in all patients, independently of the liver disease etiology. Fibroscan® is an easy, quick to perform and safe non-invasive method, reliable for assessing liver fibrosis.
Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/patologia , Cirrose Hepática , Fígado/patologia , Biópsia , Biomarcadores/análise , Doença Crônica , Estudos Transversais , Técnicas de Imagem por Elasticidade/normas , FibroseRESUMO
The prognosis and management of chronic liver disease largely depends on the extent and progression of liver fibrosis. Unfortunately, liver biopsy, an invasive and painful technique with several limitations, continues to be the gold standard for the staging and grading of fibrosis. Therefore, accurate noninvasive tests for liver injury are urgently needed. During the last years, transient elastography (Fibroscan®) has been proposed for the assessment of hepatic fibrosis in patients with chronic liver disease, by measuring liver stiffness. The aim of this study was to evaluate the effectiveness, objectivity and safety of this technique. We included 68 patients who underwent a liver biopsy in the last 18 months with a wide spectrum of chronic liver diseases. All procedures as well as the liver biopsies according to the METAVIR scoring system were analyzed by the same sonographer and the same specialist in pathology, respectively. Median value of stiffness with none or mild fibrosis (F0 and FI), and severe fibrosis or cirrhosis (F3 and F4) was 6.8 ± 3.0 kPa and 21.0 ± 15.1 kPa, respectively, with a significant difference between them (p < 0.01). The areas under the receiver operating characteristic curves showed the optimal liver stiffness cut-off values for each group. We found also a positive correlation between liver stiffness found by transient elastography and fibrosis stage on biopsy in all patients, independently of the liver disease etiology. Fibroscan® is an easy, quick to perform and safe non-invasive method, reliable for assessing liver fibrosis.
Assuntos
Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Fígado/patologia , Biomarcadores/análise , Biópsia , Doença Crônica , Estudos Transversais , Técnicas de Imagem por Elasticidade/normas , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND & AIMS: Liver fibrosis stage is traditionally assessed with biopsy, an imperfect gold standard. Two widely used techniques, FibroTest®, and liver stiffness measurement (LSM) using Fibroscan® have been validated using biopsy, and therefore the true performances of these estimates are still unknown in the absence of a perfect reference. The aim was to assess the relative accuracy of FibroTest, LSM, and biopsy using methods without gold standard in patients with chronic hepatitis C (CHC) and controls. METHODS: A total of 1289 patients with CHC and 604 healthy volunteers, with assessment of fibrosis stage by the three techniques, and alanine aminotransferase (ALT) taken as a control test, were analyzed by latent class method with random effects. In the volunteers, the false positive risk of biopsy was obtained from a large surgical sample of four normal livers. RESULTS: The latent class model with random effects permitted to conciliate the observed data and estimates of test performances. For advanced fibrosis, the specificity/sensitivity was for FibroTest 0.93/0.70, LSM 0.96/0.45, ALT 0.79/0.78 and biopsy 0.67/0.63, and for cirrhosis FibroTest 0.87/0.41, LSM 0.93/0.39, ALT 0.78/0.08 and biopsy 0.95/0.51. The analysis of the discordances between pairs suggested that the variability of the model was mainly related to the discordances between biopsy and LSM (residuals>10; p<0.0001). CONCLUSIONS: A method without the use of a gold standard confirmed the accuracy of FibroTest and Fibroscan for the diagnosis of advanced fibrosis and cirrhosis in patients with chronic hepatitis C. The variability of the model was mostly due to the discordances between Fibroscan and biopsy.
Assuntos
Biópsia/normas , Técnicas de Imagem por Elasticidade/normas , Hepatite C Crônica/patologia , Cirrose Hepática/patologia , Fígado/patologia , Alanina Transaminase/sangue , Biópsia/métodos , Bases de Dados Factuais/estatística & dados numéricos , Técnicas de Imagem por Elasticidade/instrumentação , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
PURPOSE: The aim of the study was to assess the influence of technical factors and/or lesion characteristics on the final elastographic score in solid breast nodules. MATERIALS AND METHODS: Patients with solid breast masses examined between May 2007 and May 2008 in the Radiology Department of Cluj District University Hospital were included in the study. All lesions were examined with conventional ultrasound, Doppler ultrasound and sonoelastography, according to a preset protocol. The influence of the following factors on the elastographic score was evaluated: type of section (sagittal versus transverse); size of region of interest (small versus large); amplitude and frequency of movement; initial compression (light versus strong); angulation (perpendicular versus angulated transducer); characteristics of the lesion (size and location). The reference diagnosis was the histopathology diagnosis and, in twenty cases, short-term follow-up. RESULTS: Ninety-two patients with a mean age of 48.11 years and 101 breast nodules were included in the study. The overall sensitivity and specificity for elastography were 79 % [68-88 %] and 79 % [65 - 89 %], respectively, with a negative predictive value of 74 % [60-85 %] and a positive predictive value of 84 % [72-91 %]. The following factors did not influence the elastographic score: type of section (scores on transverse and longitudinal section, Z = -0.641, p = 0.552); the amplitude and frequency of movements during the elastographic examination (Cochran's Q concordance = 0.706, p = 0.872); strong initial compression in the case of benign nodules (Z = 0.000, p = 1.000); size of the lesions. Of the elastographically benign nodules, 9 were false negative and of the 46 elastographically malignant nodules, 12 were false positive. The following factors influenced the elastographic scores: size of the region of interest (the scores were significantly different when small or large region of interest was used, Z = -0.671, p < 0.0001); transducer angulation (Z = -5.42, p < 0.0001); strong initial compression in the case of malignant nodules (Z = -6.044, p < 0.0001) and the location of the mass in the vicinity of the chest wall. CONCLUSION: The most important factors that influence the final elastographic score, leading to false negative results, are the size of the region of interest, the initial compression and angulation of the transducer, while the frequency and amplitude of movement during the examination proved to be of no importance as long as the images were obtained within a range of assessment usefulness. Changing the scanning parameters never led to false positive results in the case of malignant breast masses.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Processamento de Imagem Assistida por Computador/métodos , Carga Tumoral/fisiologia , Ultrassonografia Doppler/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/patologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Técnicas de Imagem por Elasticidade/normas , Feminino , Fibroadenoma/diagnóstico por imagem , Fibroadenoma/patologia , Humanos , Processamento de Imagem Assistida por Computador/normas , Mesenquimoma/diagnóstico por imagem , Mesenquimoma/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Tumor Filoide/diagnóstico por imagem , Tumor Filoide/patologia , Valor Preditivo dos Testes , Transdutores , Ultrassonografia Doppler/normas , Ultrassonografia Mamária/normas , Adulto JovemRESUMO
Historically, liver biopsy (LB) was the sole method to evaluate the severity of hepatic fibrosis in patients with chronic hepatitis C infection. However, LB is expensive and associated with a risk of severe complications. Therefore, noninvasive tests have been developed to assess the severity of liver fibrosis. The accuracy of Fibroscan (FS) and King's score (KS) was evaluated individually and in combination using liver histology as the reference standard. One hundred and eighty-seven patients were identified who had undergone a biopsy with a diagnosis of chronic hepatitis C virus (HCV) mono-infection (HCV RNA-positive by RT-PCR), attending King's College Hospital (n = 88) or the Royal Free Hospital (n = 99) (London) between May 2006 and December 2007. Liver fibrosis was scored using the Ishak method; significant fibrosis was defined as Ishak fibrosis stage F3-F6, and cirrhosis defined as Ishak fibrosis F5-F6. The diagnostic accuracy of each test was assessed by area under receiver operator characteristic curves (AUROC). Median age was 49 years (43-54) and 115 (61%) were male. The AUROC for FS, KS and FS + KS for the diagnosis of Ishak F3-F6 were 0.83, 0.82 and 0.85, respectively and for the diagnosis of cirrhosis (>or=F5) were 0.96, 0.89 and 0.93, respectively. The negative predictive values for the diagnosis of cirrhosis using the optimal cut-off results for fibrsocan (10.05 kPa), KS (24.3) and the two combined (26.1) were 98%, 91% and 94%, respectively. The noninvasive markers and, particularly, FS were effective tests for the prediction of cirrhosis in chronic hepatitis C. Both KS and FS also had clinical utility for the prediction of Ishak fibrosis stages F3-F6.