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1.
Artigo em Inglês | MEDLINE | ID: mdl-32450363

RESUMO

BACKGROUND & AIMS: We evaluated the accuracy of a multiparametric approach using attenuation imaging and 2-dimensional shear wave elastography (2D-SWE) in detection of steatosis and fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: We studied 102 patients with increased levels of liver enzymes or suspicion of NAFLD, examined by attenuation imaging and 2D-SWE immediately before biopsy collection and analysis (reference standard), from January 2018 to July 2019. We collected data on attenuation coefficient (dB/cm/MHz) from attenuation imaging, liver stiffness measurements, and shear wave dispersion slope (SWDS, [m/s]/kHz) from 2D-SWE. Multivariate linear regression analysis was performed to identify factors associated with each parameter. Diagnostic performance was determined from area under the receiver operating curve (AUROC) values. RESULTS: The attenuation coefficient was associated with steatosis grade (P<.01) and identified patients with steatosis grades ≥S1, ≥S2, and ≥S3 with AUROC values of 0.93, 0.88, and 0.83, respectively. Liver stiffness associated with fibrosis stage (P<.01) and lobular inflammatory activity was the only factor associated with SWDS (P<.01). SWDS detected inflammation grades ≥I1, ≥I2, and ≥I3 with AUROC values of 0.89, 0.85, and 0.78, respectively. We developed a risk scoring system to detect steatohepatitis based on attenuation coefficient (score 1 for 0.64< attenuation coefficient ≤0.70; score 2 for 0.70< attenuation coefficient ≤0.73; and score 3 for attenuation coefficient >0.73) and SWDS (score 2 for 10.5 [m/s]/kHz11.7 [m/s]/kHz), using an unweighted sum of each score. Based on histopathology analysis, 55 patients had steatohepatitis. Risk scores correlated with NAFLD activity score (rho=.73; P<.01). Our scoring system identified patients with steatohepatitis with an AUROC of 0.93-this value was significantly higher than that of other parameters (P<.05), except SWDS (AUROC, 0.89; P=.18). CONCLUSION: In evaluation of patients with suspected NAFLD, attenuation coefficient can identify patients with steatosis and liver stiffness can accurately detect fibrosis. SWDS was significantly associated with lobular inflammation. We developed a risk scoring system based on AC and SWDS that might be used to detect steatohepatitis.

2.
Sci Rep ; 10(1): 7700, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32382062

RESUMO

Ultrasonography (US) has been considered image of choice for gallbladder (GB) polyp, however, it had limitations in differentiating between nonneoplastic polyps and neoplastic polyps. We developed and investigated the usefulness of a deep learning-based decision support system (DL-DSS) for the differential diagnosis of GB polyps on US. We retrospectively collected 535 patients, and they were divided into the development dataset (n = 437) and test dataset (n = 98). The binary classification convolutional neural network model was developed by transfer learning. Using the test dataset, three radiologists with different experience levels retrospectively graded the possibility of a neoplastic polyp using a 5-point confidence scale. The reviewers were requested to re-evaluate their grades using the DL-DSS assistant. The areas under the curve (AUCs) of three reviewers were 0.94, 0.78, and 0.87. The DL-DSS alone showed an AUC of 0.92. With the DL-DSS assistant, the AUCs of the reviewer's improved to 0.95, 0.91, and 0.91. Also, the specificity of the reviewers was improved (65.1-85.7 to 71.4-93.7). The intraclass correlation coefficient (ICC) improved from 0.87 to 0.93. In conclusion, DL-DSS could be used as an assistant tool to decrease the gap between reviewers and to reduce the false positive rate.

3.
Ultraschall Med ; 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32323278

RESUMO

PURPOSE: To assess the diagnostic performance of the normalized local variance (NLV) ultrasound technique in the detection of the fatty liver using histopathology as a reference standard. MATERIALS AND METHODS: We prospectively enrolled 194 consecutive patients with clinical suspicion of diffuse liver disease or history of liver transplantation. Conventional grayscale ultrasound and NLV examinations were performed and immediately followed by liver biopsies. The degrees of fatty liver, necroinflammatory activity, and fibrosis stage were evaluated by histopathological assessment. The diagnostic performance of the NLV values in detecting each grade of fatty liver was determined using receiver operating characteristics analyses, and multivariate linear regression analyses were performed to identify variables significantly associated with the NLV values. RESULTS: The number of patients in each degree of fatty liver and hepatic fibrosis was 118/37/26/13 and 81/68/24/6/14 for none/mild/moderate/severe steatosis and F0 / F1/F2 / F3/F4 fibrosis on histopathological examinations, respectively. The area under the receiver operating characteristics curve and optimal cut-off NLV value for detecting fatty liver of varying degrees were 0.911 and 1.095 for ≥ S1, 0.974 and 1.055 for ≥ S2, and 0.954 and 1.025 for ≥ S3, respectively. Multivariate analyses revealed that not fibrosis or inflammation but rather the degree of steatosis was associated with the NLV value. CONCLUSION: The NLV value demonstrated excellent diagnostic performance for detecting varying degrees of fatty liver, and the degree of steatosis on histopathological examinations was the only significant factor affecting the NLV value.

4.
Abdom Radiol (NY) ; 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296898

RESUMO

PURPOSE: The aim of the study is to predict the rate of liver regeneration in recipients after living-donor liver transplantation using preoperative CT texture and shape analysis of the future graft. METHODS: 102 donor-recipient pairs who underwent living-donor liver transplantation using right lobe grafts were retrospectively included. We semi-automatically segmented the future graft from preoperative CT. The volume of the future graft (LVpre) was measured, and texture and shape analyses were performed. The graft liver was segmented from postoperative follow-up CT and the volume of the graft (LVpost) was measured. The regeneration index was defined by the following equation: [(LVpost-LVpre)/LVpre] × 100(%). We performed a stepwise, multivariate linear regression analysis to investigate the association between clinical, texture and shape parameters and the RI and to make the best-fit predictive model. RESULTS: The mean regeneration index was 47.5 ± 38.6%. In univariate analysis, the volume of the future graft, energy, effective diameter, surface area, sphericity, roundnessm, compactness1, and grey-level co-occurrence matrix contrast as well as several clinical parameters were significantly associated with the regeneration index (p < 0.05). The best-fit predictive model for the regeneration index made by multivariate analysis was as follows: Regeneration index (%) = 127.020-0.367 × effective diameter - 1.827 × roundnessm + 47.371 × recipient body surface area (m2) + 12.041 × log(recipient white blood cell count) (× 103/µL)+ 18.034 (if the donor was female). CONCLUSION: The effective diameter and roundnessm of the future graft were associated with liver regeneration. Preoperative CT texture analysis of future grafts can be useful for predicting liver regeneration in recipients after living-donor liver transplantation.

5.
Eur Radiol ; 30(5): 2890-2901, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32025835

RESUMO

OBJECTIVES: To identify MRI features that are helpful for the differentiation of gallbladder neuroendocrine tumors (GB-NETs) from gallbladder adenocarcinomas (GB-ADCs) and to evaluate their prognostic values. METHODS: Between January 2008 and December 2018, we retrospectively enrolled patients who underwent MRI for GB malignancy. Two radiologists independently assessed the MRI findings and reached a consensus. Significant MRI features, which distinguish GB-NETs from GB-ADCs, were identified. Cox regression analyses were performed to find MRI features that were prognostic for overall survival. RESULTS: There were 63 patients with GB-NETs (n = 21) and GB-ADCs (n = 42). Compared with GB-ADCs, GB-NETs more frequently demonstrated the following MRI features: well-defined margins, intact overlying mucosa, and thick rim contrast enhancement and/or diffusion restriction (ps < 0.001). Liver metastases were more common and demonstrated thick rim contrast enhancement and diffusion restriction in GB-NETs (ps < 0.001). Lymph node (LN) metastasis showed thick rim diffusion restriction more often in GB-NETs than in GB-ADCs (p = 0.009). On quantitative analysis, the sizes of the GB mass and metastatic LNs in GB-NETs were larger than those in GB-ADCs (p = 0.002 and p = 0.010, respectively). The ratio of apparent diffusion coefficient values between the lesion and the spleen was lower in the GB mass, liver metastases, and LN metastases of GB-NETs than those of GB-ADCs (p < 0.001, p = 0.017, and p < 0.001, respectively). Survival analysis revealed that a large metastatic LN (hazard ratio 1.737; 95% confidence interval, 1.112-2.712) was the only poor prognostic factor (p = 0.015). CONCLUSION: Several MRI features aided in differentiating between GB-NETs and GB-ADCs. A large metastatic LN was associated with poor survival. KEY POINTS: • Compared with gallbladder adenocarcinomas (GB-ADCs), neuroendocrine tumors (GB-NETs) and their metastases to the liver and lymph nodes more frequently demonstrated a thick rim appearance on contrast-enhanced MRI and diffusion-weighted images. • The ratio of apparent diffusion coefficient values between the lesion and the spleen was significantly lower for the primary mass, liver metastases, and lymph node metastases of GB-NETs than for those of GB-ADCs. • A large metastatic lymph node was the only poor prognostic factor for overall survival in patients with GB-NETs and GB-ADCs.

6.
Liver Int ; 40(5): 1189-1200, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32056353

RESUMO

BACKGROUND & AIMS: A recent study showed that serum tumour marker-based MoRAL score (11×√protein induced by vitamin K absence-II [PIVKA] +2×√alpha-foetoprotein [AFP]) can reflect both tumour burden and aggressiveness of hepatocellular carcinoma (HCC). This study aimed to evaluate whether baseline MoRAL score could predict tumour recurrence after radiofrequency ablation (RFA) for very-early/early-stage HCC. METHODS: A total of 576 HCC patients who underwent RFA as initial treatment were enrolled from two tertiary referral hospitals (256 in development cohort and 320 in validation cohort). The primary endpoint was recurrence-free survival (RFS) and the secondary endpoints included cumulative risks of intrahepatic distant recurrence (IDR) and extrahepatic metastasis (EM). RESULTS: In the development cohort, MoRAL score was an independent prognostic factor of RFS (P = .02). The optimal cutoff MoRAL score for predicting RFS was 68. Patients with high MoRAL score (>68) showed significantly shorter RFS than did those with low MoRAL score (hazard ratio [HR] = 2.04, P < .001). The 5-year RFS rates were 32.3% and 53.2% in high- and low-MoRAL groups respectively. Risks of both IDR (HR = 1.76, P = .003) and EM (HR = 8.25, P = .006) were also significantly higher in high MoRAL group. These results were reproduced in the validation cohort: RFS (HR = 1.81, P < .001; 5-year RFS rates = 27.7% vs 53.6%) was significantly shorter and risks of IDR (HR = 1.59, P = .003) and EM (HR = 6.19, P = .004) were significantly higher in high MoRAL group. CONCLUSION: A high MoRAL score of >68 was significant a predictive factor of tumour recurrence after RFA for very-early/early-stage HCC. Moreover, it might be warranted to evaluate EM in patients with high baseline MoRAL scores.

7.
PLoS One ; 15(1): e0227492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929591

RESUMO

OBJECTIVE: To evaluate the role of computerized 3D CT texture analysis of the pancreas as quantitative parameters for assessing diabetes. METHODS: Among 2,493 patients with diabetes, 39 with type 2 diabetes (T2D) and 12 with type 1 diabetes (T1D) who underwent CT using two selected CT scanners, were enrolled. We compared these patients with age-, body mass index- (BMI), and CT scanner-matched normal subjects. Computerized texture analysis for entire pancreas was performed by extracting 17 variable features. A multivariate logistic regression analysis was performed to identify the predictive factors for diabetes. A receiver operator characteristic (ROC) curve was constructed to determine the optimal cut off values for statistically significant variables. RESULTS: In diabetes, mean attenuation, standard deviation, variance, entropy, homogeneity, surface area, sphericity, discrete compactness, gray-level co-occurrence matrix (GLCM) contrast, and GLCM entropy showed significant differences (P < .05). Multivariate analysis revealed that a higher variance (adjusted OR, 1.002; P = .005), sphericity (adjusted OR, 1.649×104; P = .048), GLCM entropy (adjusted OR, 1.057×105; P = .032), and lower GLCM contrast (adjusted OR, 0.997; P < .001) were significant variables. The mean AUCs for each feature were 0.654, 0.689, 0.620, and 0.613, respectively (P < .05). In subgroup analysis, only larger surface area (adjusted OR, 1.000; P = .025) was a significant predictor for T2D. CONCLUSIONS: Computerized 3D CT texture analysis of the pancreas could be helpful for predicting diabetes. A higher variance, sphericity, GLCM entropy, and a lower GLCM contrast were the significant predictors for diabetes.


Assuntos
Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Pâncreas/diagnóstico por imagem , Adulto , Idoso , Área Sob a Curva , Índice de Massa Corporal , Entropia , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Curva ROC , Tomografia Computadorizada por Raios X
8.
Eur Radiol ; 30(3): 1554-1563, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31705252

RESUMO

OBJECTIVES: To investigate the efficacy and safety of a new portable ultrasound-guided high-intensity focused ultrasound system (USgHIFU) with advanced targeting and beam steering technology for the treatment of uterine fibroids. METHODS: Fifty-nine uterine fibroids from 36 participants (mean age, 44.9 ± 4.1 years) were included from November 2013 to November 2015. All participants were treated with HIFU, with 3D electronic steering. MR imaging studies were performed before HIFU, immediately after HIFU, and 1 month and 3 (or 5) months after the HIFU treatment. The non-perfused volume ratio (NPVR), fibroid volume shrinkage (FVS), symptom improvement, quantified life quality assessment, and safety were analyzed. A long-term follow-up was conducted in July to December 2017 (mean, 32.2 months). RESULTS: The volume of the treated uterine fibroids ranged from 7.5 to 274.4 cm3 (mean, 69.8 cm3; SD, 64.3 cm3). The mean NPVR on the immediate post-HIFU MR imaging was 74.8 ± 25.2%. The mean FVS was 17.3% at 1 month, 33.3% at 3 months, and 45.1% at 5 months after HIFU treatment. The mean treatment time was 44.6 ± 28.2 min per fibroid and 72.9 ± 31.4 min per participant. Uterine fibroid-related symptoms and quality of life showed statistically significant improvement after the HIFU treatment. No significant symptoms related to safety or complications occurred. In the long-term follow-up, 78.8% of those surveyed were satisfied with their HIFU treatment. CONCLUSION: This clinical trial showed that a portable USgHIFU with advanced functions may safely and effectively treat uterine fibroids. KEY POINTS: • A portable compact ultrasound-guided high-intensity focused ultrasound (HIFU) can effectively and safely treat uterine fibroids. • Advanced functions, such as portability, targeted forecasting, electronic beam steering, and interleaved scanning, might be helpful in enhancing the clinical applicability of ultrasound-guided high-intensity focused ultrasound. • In the long-term follow-up of more than 2 years, approximately 80% of those surveyed were satisfied with their HIFU treatment.

9.
Abdom Radiol (NY) ; 45(1): 55-63, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31332503

RESUMO

PURPOSE: To determine the added value of CEUS on arterial phase non-hyperenhancement (APNHE) observations (LR-3 and LR-4) of CT/MRI in high-risk patients. METHODS: Forty-three patients with APNHE observations (≥ 2 cm) from CT/MRI were prospectively enrolled in this IRB-approved study and underwent CEUS. All observations were assessed by LI-RADS for CT/MRI and CEUS. The hemodynamic findings were compared. The mean follow-up period was 11.8 ± 2.1 months. Reference standard was made on 34-APNHE observations based on biopsy (n = 2), surgery (n = 2), and follow-up image (n = 30). RESULTS: The median of observation size was 2.3 cm (IQR 2.0-2.5 cm). Among the 43-APNHE observations, 12-observations (27.9%) were further presented as arterial phase hyperenhancement (APHE) in CEUS with early (n = 1, CEUS LR-M), late (n = 10, CEUS LR-5), or no (n = 1, CEUS LR-4) washout. Compared to CT, CEUS presented concordant enhancement patterns in 16 (44.4%) in AP and 20 (55.6%) in PVP, respectively. Similarly, 13 (59.1%) and 14 (63.6%) observations showed concordant enhancement patterns between CEUS and MRI in AP and PVP, respectively. Of the 34-APNHE observations with final diagnosis (hepatocellular carcinoma [HCC] n = 12; intrahepatic cholangiocarcinoma [IHCC], n = 1; non-malignancy, n = 21), 4 HCCs (33.3%) and 1 IHCC (100%) were additionally diagnosed by CEUS, while 1 non-malignant lesion (4.5%) was misdiagnosed as HCC by CEUS. CONCLUSION: Adding CEUS to APNHE observations from CT/MRI would be useful not only for definitely diagnosing HCC (CEUS LR-5) but also for other malignancies (CEUS LR-M). The discordance of dynamic features between the LI-RADS for CEUS and CT/MRI may reflect the different properties of contrast media, although the systems are not interchangeable.

10.
Ultrasonography ; 39(1): 70-78, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31639886

RESUMO

PURPOSE: The purpose of this study was to prospectively evaluate whether monitoring hepatic steatosis by ultrasonography with acoustic structure quantification (ASQ) is feasible, using magnetic resonance spectroscopy (MRS) as the reference standard. METHODS: Thirty-six patients with suspected fatty liver disease underwent both untrasonography with ASQ and MRS on the same day. After a mean follow-up period of 11.4±2.5 months, follow-up ultrasonography with ASQ and MRS were performed on 27 patients to evaluate whether hepatic steatosis had improved. The focal disturbance (FD) ratio, as calculated using ASQ, and the hepatic fat fraction (HFF), estimated by MRS, were obtained at both initial and follow-up examinations. Pearson correlation coefficients were calculated to assess the correlations between ordinal values. RESULTS: The FD ratio showed a strong, negative linear correlation with the HFF after logarithmic transformation of both variables from the initial examinations of 36 patients (ρ=-0.888, P<0.001) and the follow-up examinations of 27 patients (ρ=-0.920, P<0.001). There was also a significant, negative linear correlation between the change in the logarithm of the FD ratio and the change in the logarithm of the HFF by MRS over the follow-up period (ρ=-0.645, P<0.001). In 16 patients with an increased FD ratio on follow-up, the HFF on follow-up MRS significantly decreased, and high-density lipoprotein levels significantly increased, whereas low-density lipoprotein levels tended to decrease. CONCLUSION: The FD ratio was significantly correlated with the HFF at both the initial and follow-up examinations, and there was also a significant correlation between changes in the FD ratio and changes in the HFF over the follow-up period.

11.
Eur Radiol ; 30(3): 1634-1643, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31781931

RESUMO

OBJECTIVES: To investigate whether multiparametric magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography (PET) can be helpful in differentiating gastrointestinal stromal tumors (GISTs) from non-GISTs and high-risk GISTs from low-risk GISTs. METHODS: This retrospective study included 56 patients with pathologically confirmed GISTs (n = 39), leiomyoma (n = 8), schwannoma (n = 5), heterotopic pancreas (n = 3), and glomus tumor (n = 1) who underwent MRI and/or PET examinations. Two radiologists reviewed MRI regarding location, shape, contour, growth pattern, margin, signal intensity (SI) on T1- (T1WI) and T2-weighted images (T2WI), degree and pattern of enhancement, hemorrhage, and necrosis. Mean apparent diffusion coefficient (ADC) and maximum standardized uptake value (SUVmax) were measured. Imaging features were compared among non-GISTs, low-risk GISTs, and high-risk GISTs using uni- and multivariate statistical analyses. RESULTS: Size, longitudinal location, shape, contour, growth pattern, SI on T1- and T2WI, enhancement pattern, hemorrhage, necrosis, ADC, and SUVmax were significantly different among non-GISTs, low-risk GISTs, and high-risk GISTs (p < 0.05). On multivariate analysis, SI on T2WI (hazard ratio [HR], 66.0; p = 0.002) was the only independent variable for differentiating GISTs from non-GISTs whereas enhancement pattern (HR, 56.0; p = 0.041), ADC (HR, 0.997; p = 0.01), and SUVmax (HR, 2.08; p = 0.027) were significant features for differentiating between high-risk and low-risk GISTs. CONCLUSIONS: Several qualitative and quantitative MRI and PET features including ADC and SUVmax values are significantly different among non-GISTs, low-risk GISTs, and high-risk GISTs. Multiparametric information obtained from MRI with or without PET can be useful for differentiation of gastric subepithelial tumors as well as for determining patients' management and prognosis. KEY POINTS: • Several qualitative MRI features are helpful in distinguishing gastrointestinal stromal tumors (GISTs) from non-GISTs as well as high-risk GISTs from low-risk GISTs. • Apparent diffusion coefficient value on diffusion-weighted imaging can be useful in distinguishing GISTs from non-GISTs as well as high-risk GISTs from low-risk GISTs. • PET has the potential to distinguish between high-risk and low-risk GISTs.

12.
Radiology ; 293(2): 327-333, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31502939

RESUMO

Background Allograft damage (hepatic parenchymal damage) after liver transplant is associated with the degree of necroinflammation in graft liver. According to a recent animal study, shear-wave dispersion slope obtained at US shear-wave elastography (SWE) is associated with necroinflammatory activity in the liver. Purpose To evaluate the role of shear-wave dispersion slope in detecting allograft damage after liver transplant. Materials and Methods In this prospective study, 104 liver transplant recipients underwent percutaneous liver biopsy for allograft evaluation from December 2017 to November 2018. All participants underwent allograft SWE examination just before liver biopsy, and liver stiffness and shear-wave dispersion slope were obtained. Allograft damage was diagnosed by histopathologic analysis. Clinical and imaging factors related to liver stiffness and shear-wave dispersion slope were determined by multivariable linear regression analysis. Diagnostic performance of each variable in detecting allograft damage was evaluated by comparing area under the receiver operating curve (AUC) values. Results There were 104 study participants (35 women); median age was 56 years (interquartile range, 50-62 years). Allograft damage was found in 46 of 104 (44.2%) of participants. The median liver stiffness (8.2 kPa vs 6.3 kPa; P < .01) and shear-wave dispersion slope (14.4 [m/sec]/kHz vs 10.4 [m/sec]/kHz; P < .01) were higher in participants with allograft damage than in those without damage, respectively. Fibrosis stage was the only determinant factor for liver stiffness (coefficient, 1.8 kPa per fibrosis stage; 95% confidence interval: 0.1, 3.5; P = .03), whereas both fibrosis stage (coefficient, 1.4 [m/sec]/kHz per fibrosis stage; 95% confidence interval: 0.3, 2.6; P = .02) and necroinflammatory activity (coefficient, 1.6 [m/sec]/kHz per necroinflammatory activity grade; 95% confidence interval: 0.5, 2.7; P < .01) affected shear-wave dispersion slope. The AUC for shear-wave dispersion slope in detecting allograft damage was 0.86, which was higher than that of liver stiffness (AUC, 0.75; P < .01). Conclusion Shear-wave dispersion slope determined at US shear-wave elastography may help in detecting allograft damage after liver transplant. © RSNA, 2019 Online supplemental material is available for this article.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepatopatias/diagnóstico por imagem , Transplante de Fígado , Complicações Pós-Operatórias/diagnóstico por imagem , Aloenxertos , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
13.
Acad Radiol ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31494001

RESUMO

OBJECTIVES: To investigate the diagnostic performance of liver stiffness (LS) measurements on two-dimensional (2D) shear wave elastography (SWE) for the assessment of hepatic fibrosis using LS measurements on MR elastography (MRE) as the reference standard and the prediction of clinically significant portal hypertension (CSPH). METHODS: In this prospective study, 101 patients with chronic liver disease or cirrhosis underwent both MRE and SWE. After exclusion of technical failure on MRE (n = 5), technical failure/unreliable measurement on SWE (n = 4), LS measurements obtained on SWE with the aid of propagation maps were correlated with those of the MRE using Pearson's correlation analysis. Diagnostic performances for significant fibrosis (≥F2: MRE of ≥2.99 kPa) or cirrhosis (F4: MRE of ≥3.63 kPa) and for the prediction of CSPH were assessed using receiver operating characteristics (ROC) curve analysis. RESULTS: LS values on SWE showed a strong correlation with those on MRE (r = 0.846, P < 0.001). For the diagnosis of significant fibrosis or cirrhosis in patients with hepatitis B virus-related liver disease (n = 75), SWE showed areas under the ROC curves (AUC) of 0.975 and 0.912, respectively (95% confidence interval [CI], 0.910-997, and 0.824-0.965). For the prediction of CSPH, the AUC of SWE was 0.818 (95% CI, 0.712-0.898), and when an LS value of 11.5 kPa was applied as a cut-off, SWE showed a sensitivity of 81.5% and a specificity of 72.9%. CONCLUSION: LS measurements on 2D SWE were demonstrated to be well correlated with those obtained with MRE, and thus, may provide good diagnostic performance for the prediction of hepatic fibrosis and the presence of CSPH.

14.
BMC Med Imaging ; 19(1): 76, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462212

RESUMO

BACKGROUND: Dual-layer spectral detector CT (SDCT) may provide several theoretical advantages over pre-existing DECT approaches in terms of adjustment-free sampling number and dose modulation, beam hardening correction, and production spectral images by post-processing. In addition, by adopting noise reduction algorithm, high contrast resolution was expected even in low keV level. We surmised that this improvement would be beneficial to obese people. Therefore, our aim of study is to compare image quality of virtual monochromatic spectral images (VMI) and polychromatic images reconstructed from SDCT with different body size and radiation dose using anthropomorphic liver phantom. METHODS: One small and one large size of body phantoms, each containing eight (four high- and four low-contrast) simulated focal liver lesions (FLLs) were scanned by SDCT (at 120 kVp) using different Dose Right Indexes (DRIs). VMI were reconstructed from spectral base images from 40 keV to 200 keV. Hybrid iterative reconstruction (iDose4) was used for polychromatic image reconstruction. Image noise and contrast to noise ratio (CNR) were compared. Five radiologists independently rated lesion conspicuity, diagnostic acceptability and subjective noise level in every image sets, and determined optimal keV level in VMI. RESULTS: Compare with conventional polychromatic images, VMI showed superior CNR at low keV level regardless of phantom size at every examined DRIs (Ps < 0.05). As body size increased, VMI had more gradual CNR decrease and noise increase than conventional polychromatic images. For low contrast FLLs in large phantom, lesion conspicuities at low radiation dose levels (DRI 16 and 19) were significantly increased in VMI (Ps < 0.05). Subjective image noise and diagnostic acceptabilities were significantly improved at VMI in both phantom size. CONCLUSIONS: VMI of dual-layer spectral detector CT with noise reduction algorithm provides improved CNR, noise reduction, and better subjective image quality in imaging of obese simulated liver phantom compared with polychromatic images. This may hold promise for improving detection of liver lesions and improved imaging of obese patients.


Assuntos
Fígado/diagnóstico por imagem , Obesidade/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Tamanho Corporal , Humanos , Variações Dependentes do Observador , Imagens de Fantasmas , Doses de Radiação , Razão Sinal-Ruído
15.
Korean J Radiol ; 20(9): 1399-1407, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31464118

RESUMO

OBJECTIVE: To evaluate the diagnostic performance of the normalized local variance (NLV) ultrasound technique in the assessment of hepatic steatosis, and to identify the factors that influence the NLV value using histopathological examination as the reference standard. MATERIALS AND METHODS: Forty male Sprague-Dawley rats were fed a methionine-choline-deficient diet for variable periods (0, 2, 4, 6, 8, 10, or 12 days or 2, 3, or 4 weeks; four rats per group). At the end of each diet duration, magnetic resonance spectroscopy (MRS) and NLV examination were performed. Thereafter, the rats were sacrificed and their livers were histopathologically evaluated. Receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic capability of the NLV value in the detection of varying degrees of hepatic steatosis. Univariate and multivariate linear regressions were used to determine the factors associated with the NLV value. RESULTS: The areas under the ROC curve for the detection of mild, moderate, and severe hepatic steatosis were 0.953, 0.896, and 0.735, respectively. The NLV value showed comparable diagnostic performance to that of MRS in the detection of ≥ mild or ≥ moderate hepatic steatosis. Multivariate linear regression analysis revealed that the degree of hepatic steatosis was the only significant factor affecting the NLV value (p < 0.001). CONCLUSION: The NLV value of ultrasound demonstrated satisfactory diagnostic performance in the assessment of varying degrees of hepatic steatosis. The degree of hepatic steatosis was the only significant factor that affected the NLV value.

16.
Korean J Radiol ; 20(7): 1114-1123, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31270975

RESUMO

OBJECTIVE: To determine the feasibility of microvascular flow imaging (MVFI) in comparison with color/power Doppler imaging (CDI/PDI) for detection of intratumoral vascularity in suspected post-transarterial chemoembolization (TACE) residual or recurrent hepatocellular carcinomas (HCCs) by using contrast-enhanced ultrasonography (CEUS) or hepatic angiography (HA) findings as the reference standard. MATERIALS AND METHODS: One hundred HCCs (mean size, 2.2 cm) in 100 patients treated with TACE were included in this prospective study. CDI, PDI, and MVFI were performed in tandem for evaluating intratumoral vascularity of the lesions by using an RS85 ultrasound scanner (Samsung Medison Co., Ltd.). Intratumoral vascularity in each technique was assessed by two radiologists in consensus by using a 5-point scale. Then, one of the two radiologists and another radiologist performed additional image review in the reverse order (MVFI-PDI-CDI) for evaluation of intra- and interobserver agreements. Results were then compared with those of either HA or CEUS as the reference. The McNemar test, logistic regression analysis, and intraclass correlation coefficient (ICC) were used. RESULTS: CEUS or HA revealed intratumoral vascularity in 87% (87/100) of the tumors. Sensitivity (79.3%, 69/87) and accuracy (80.0%, 80/100) of MVFI were significantly higher than those of CDI (sensitivity, 27.6% [24/87]; accuracy, 37.0% [37/100]) or PDI (sensitivity, 36.8% [32/87]; accuracy, 44.0% [44/100]) (all p < 0.05). CDI, PDI, and MVFI presented excellent intraobserver (ICCs > 0.9) and good interobserver agreements (ICCs > 0.6). CONCLUSION: MVFI demonstrated significantly higher sensitivity and accuracy than did CDI and PDI for the detection of intratumoral vascularity in suspected residual or recurrent HCCs after TACE.

17.
Eur J Radiol ; 116: 34-40, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31153571

RESUMO

OBJECTIVES: To compare the virtual non-contrast (VNC) images acquired through dual-energy computed tomography (DECT) with the true non-contrast (TNC) images in the detection of biliary stones and to calculate dose reduction by replacing TNC images with VNC images. METHODS: Between March 2017 and April 2018, we retrospectively enrolled 75 patients with suspicious biliary disease who underwent dual-source DECT and surgery and/or endoscopic intervention within 2 months from the CT. Biliary stones were present in 45 patients. The sensitivity and specificity for detecting gallstone and common bile duct (CBD) stone were compared between the VNC and TNC using McNemar test. In addition, the possible reduction in radiation dose was calculated. RESULTS: In our study, 37 patients had gallstones, 2 had CBD stones, and 6 had both gallstone and CBD stones. For detection of gallstones, the sensitivity and specificity were 90.7% (39/43) and 87.5% (28/32), respectively, for the TNC images, and 88.4% (38/43) and 90.6% (29/32), respectively, for the VNC images. With respect to CBD stones, the sensitivity and specificity were 87.5% (7/8) and 98.5% (66/67), respectively, for the TNC images, and 75.0% (6/8) and 100% (67/67), respectively, for the VNC images. There was no significant difference in the sensitivity and specificity between each image set (P > 0.05). The radiation dose reduction of 22.4 ± 1.3% is expected by omitting TNC images. CONCLUSIONS: The VNC images derived from DECT were comparable to the TNC images for the detection of biliary stones and may replace the TNC images to reduce radiation dose.


Assuntos
Sistema Biliar/diagnóstico por imagem , Cálculos Biliares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
18.
Eur Radiol ; 29(12): 6458-6468, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31254061

RESUMO

OBJECTIVES: To predict residual tumor (R) classification in patients with a surgery for gallbladder (GB) cancer, using preoperative CT. METHODS: One hundred seventy-three patients with GB cancer who underwent CT and subsequent surgery were included. Two radiologists assessed CT findings, including tumor morphology, location, T stage, adjacent organ invasion, hepatic artery (HA) invasion, portal vein invasion, lymph node metastasis, metastasis, resectability, gallstone, and combined cholecystitis. The R classification was categorized as no residual tumor (R0) and residual tumor (R1 or R2). We analyzed the correlation between CT findings and R classification. We also followed up the patients as long as five years and analyzed the relationship between the R classification and the overall survival (OS). RESULTS: There were 134 patients with R0 and 39 patients with R1/R2. On multivariable analysis, liver invasion (Exp(B) = 3.19, p = 0.010), bile duct invasion (Exp(B) = 3.69, p = 0.031), and HA invasion (Exp(B) = 3.74, p = 0.039) were independent, significant predictors for residual tumor. When two of these three criteria were combined, the accuracy for predicting a positive resection margin was 83.38% with a specificity of 93.28%. The OS and the median patient survival time differed significantly according to the resection margin, i.e., 56.0% and 134.4 months in the R0 resection and 5.1% and 10.8 months in the R1/R2 resection group (p < 0.001). CONCLUSIONS: Preoperative CT findings could aid in planning surgery and determining the resectability using the high-risk findings of residual tumor, including liver invasion, bile duct invasion, and HA invasion. KEY POINTS: • Liver invasion, bile duct invasion, and HA invasion were significant preoperative CT predictors for residual tumor in GB cancer. • HA invasion showed the highest OR on multivariate analysis and the highest predictor point on a nomogram for predicting a positive resection margin. • Association of two factors can predict positive resection margin with an accuracy of 83.38% and a specificity of 93.28%.


Assuntos
Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Cuidados Pré-Operatórios/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Vesícula Biliar/diagnóstico por imagem , Vesícula Biliar/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasia Residual , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Análise de Sobrevida
19.
Eur Radiol ; 29(12): 6499-6507, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31175413

RESUMO

OBJECTIVES: To evaluate the diagnostic performance of attenuation imaging (ATI) in the detection of hepatic steatosis compared with a histopathology gold standard. METHODS: We prospectively enrolled 108 consecutive patients (35 males; median age, 54.0 years) who underwent percutaneous liver biopsy for evaluation of diffuse liver disease between January 2018 and November 2018 in a tertiary academic center. Grayscale ultrasound examination with ATI was performed just before biopsy, and an attenuation coefficient (AC) was obtained from each patient. The degree of hepatic steatosis, fibrosis stage, and necroinflammatory activity were assessed on histopathologic examination. The significant factor associated with the AC was found by a linear regression analysis, and the diagnostic performance of the AC for the classification into each hepatic steatosis stage was evaluated by receiver operating characteristic (ROC) analysis. RESULTS: The distribution of hepatic steatosis grade on histopathology was 53/11/22/16/6 for none/mild (< 10%)/mild (≥ 10%)/moderate/severe steatosis, respectively. The area under the ROC curve, sensitivity, specificity, and optimal cutoff AC value for detection of hepatic steatosis ranged from 0.843-0.926, 74.5-100.0%, 77.4-82.8%, and 0.635-0.745, respectively. Multivariate analysis revealed that the degree of steatosis was the only significant determinant factor for the AC. CONCLUSIONS: The AC from ATI provided good diagnostic performance in detecting the varying degrees of hepatic steatosis. The degree of steatosis was the only significant factor affecting the AC, whereas fibrosis and inflammation were not. KEY POINTS: • Attenuation imaging (ATI) is based on two-dimensional grayscale ultrasound images that can incorporate into routine ultrasound examinations with less than 2 min of acquisition time. • ATI provided good diagnostic performance in detecting the varying degrees of hepatic steatosis with an area under the ROC curves ranging from 0.843 to 0.926, and there was no technical failure in this study indicating high applicability of this technique. • The degree of hepatic steatosis was the only significant factor affecting the result of ATI examination.


Assuntos
Fígado Gorduroso/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Adulto , Biópsia , Biópsia por Agulha , Estudos de Avaliação como Assunto , Fígado Gorduroso/patologia , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
20.
Med Ultrason ; 21(2): 109-116, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31063512

RESUMO

AIMS: To determine whether contrast-enhanced US using perfluorobutane-containing microbubbles (SEUS) would be helpful for planning a hepatic biopsy. MATERIAL AND METHODS: This prospective study included 40 patients who planned to undergo hepatic biopsy for focal hepatic lesions. All patients underwent B-mode US followed by SEUS. The radiologist evaluated the number of detected lesions, presence of necrosis, conspicuity of target lesion and technical feasibility using 4-point scale. Technical failure and occurrence of change of the target were also assessed. Computer tomography (CT) or magnetic resonance (MR) images were the reference techniques. RESULTS: The mean number of lesions detected on CT and MR images was 6.5±8.4. In 20 (50%) of 40 patients, more focal lesions were detected on SEUS. Targeted lesion was changed in sixpatients (15%) on SEUS. Mean number of detected lesions on SEUS was significantly higher comparing with B-US (5.1±6.2 vs. 2.8±3.8, p<0.001). Conspicuity of the targeted lesion was improved in 67.5% (27 of 40) on SEUS and significantly more visualized than B-US (3.6±0.8 vs. 2.8±0.9, p<0.001). In 7 more patients the necrosis within the lesion was visualized (17.5%) using SEUS. The technical feasibility on SEUS was significantly higher than B-US (2.3±1.0 vs. 3.3±0.9, p<0.001). Technical failure was observed in only one patient (2.5%). CONCLUSIONS: SEUS is a helpful technique for planning the hepatic biopsyin terms of detection, improving lesion conspicuity, tumor viable portion assessment and consequently higher operator confidence, compared with B-US.


Assuntos
Meios de Contraste , Fluorcarbonetos , Aumento da Imagem/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Ultrassonografia/métodos , Adulto , Idoso , Biópsia , Estudos de Viabilidade , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Microbolhas , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
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