To investigate whether multiphasic MDCT enhancement profiles can help to identify PTEN expression in clear cell renal cell carcinomas (ccRCCs). Lack of PTEN expression is associated with worsened overall survival, a more advanced Fuhrman grade, and a greater likelihood of lymph mode metastasis.
MethodsWith IRB approval for this retrospective study, we derived a cohort of 103 histologically proven ccRCCs with preoperative 4-phase renal mass MDCT from 2001–2013. Following manual segmentation, a computer-assisted detection algorithm selected a 0.5-cm-diameter region of maximal attenuation within each lesion in each phase; a 0.5-cm-diameter region of interest was manually placed on uninvolved renal cortex in each phase. The relative attenuation of each lesion was calculated as [(Maximal lesion attenuation − cortex attenuation)/cortex attenuation] × 100. Absolute and relative attenuation in each phase were compared using t tests. The performance of multiphasic enhancement in identifying PTEN expression was assessed with logistic regression analysis.
ResultsPTEN-positive and PTEN-negative ccRCCs both exhibited peak enhancement in the corticomedullary phase. Relative corticomedullary phase attenuation was significantly greater for PTEN-negative ccRCCs in comparison to PTEN-positive ccRCCs (33.7 vs. 9.5, p = 0.03). After controlling for lesion stage and size, relative corticomedullary phase attenuation had an accuracy of 84% (86/103), specificity of 100% (84/84), sensitivity of 11% (2/19), positive predictive value of 100% (2/2), and negative predictive value of 83% (84/101) in identifying PTEN expression.
ConclusionRelative corticomedullary phase attenuation may help to identify PTEN expression in ccRCCs, if validated prospectively.
相似文献The purpose of the study is to evaluate the utility of apparent diffusion coefficient (ADC), chemical shift signal intensity index (SII), and contrast enhancement in distinguishing between benign lesions and renal cell carcinoma (RCC) and between subtypes of renal lesions.
MethodsThis retrospective study included 98 renal lesions (≤ 3 cm) on MRI with correlative surgical pathology. Scanner field strength, lesion location, and size were recorded. Two readers blinded to surgical pathology independently measured ADC ratio (ADC lesion/ADC non-lesion kidney), SII, and absolute/relative enhancement in the corticomedullary and nephrographic phases of contrast.
ResultsThere were 76 malignant and 22 benign lesions. 42 RCC were clear cell (ccRCC), 19 papillary (pRCC), 5 chromophobe (cbRCC). Benign lesions included both solid and cystic lesions. Interreader agreement for all variables was good–excellent (ICC 0.70–0.91). There was no difference in ADC or SII between benign and malignant lesions. There was greater absolute corticomedullary enhancement of benign versus malignant lesions (150.0 ± 111.5 vs. 81.1 ± 74.8, p = 0.0115), which did not persist when excluding pRCC. For lesion subtype differentiation, ADCratio for pRCC was lower than benign lesions (0.74 ± 0.35 vs. 1.03 ± 0.46, p = 0.0246). ccRCC demonstrated greater SII than other RCC (0.09 ± 0.22 vs. 0.001 ± 0.26, p = 0.0412). Oncocytomas and angiomyolipoma (AML) showed greater absolute corticomedullary enhancement than ccRCC and pRCC (145.6 ± 65.2 vs. 107.2 ± 85.3, p = 0.043 and 186.2 ± 93.9 vs. 37.6 ± 35.3, p = 0.0108), respectively.
ConclusionsWhile corticomedullary-phase enhancement was a differentiating feature, quantitative metrics from diffusion and chemical shift imaging cannot reliably differentiate benign from malignant lesions. Quantitative assessment may be useful in differentiating some benign and malignant lesion subtypes.
相似文献The purpose of the study was to evaluate the feasibility of using contrast-enhanced computed tomography (CECT)-based texture analysis (CTTA) metrics to differentiate between juxtatumoral perinephric fat (JPF) surrounding low-grade (ISUP 1–2) versus high-grade (ISUP 3–4) clear cell renal cell carcinoma (ccRCC).
MethodsIn this IRB-approved study, we retrospectively queried the surgical database between June 2009 and April 2016 and identified 83 patients with pathologically confirmed ccRCC (low grade: n = 54, mean age = 61.5 years, 18F/35M; high grade n = 30, mean age = 61.7 years, 8F/22M) who also had pre-operative multiphase CT acquisitions. CT images were transferred to a 3D workstation, and nephrographic phase JPF regions were manually segmented. Using an in-house developed Matlab program, a CTTA panel comprising of texture metrics extracted using six different methods, histogram, 2D- and 3D-Gray-level co-occurrence matrix (GLCM) and Gray-level difference matrix (GLDM), and 2D-Fast Fourier Transform (FFT) analyses, was applied to the segmented images to assess JPF textural heterogeneity in low- versus high-grade ccRCC. Univariate analysis and receiver-operator characteristics (ROC) analysis were used to assess interclass differences in texture metrics and their prediction accuracy, respectively.
ResultsAll methods except GLCM consistently revealed increased heterogeneity in the JPF surrounding high- versus low-grade ccRCC. FFT showed increased complexity index (p < 0.01). Histogram analysis showed increased kurtosis and positive skewness in (p < 0.03), and GLDM analysis showed decreased measure of correlation coefficient (MCC) (p < 0.04). Several of the GLCM metrics showed statistically significant (p < 0.04) textural differences between the two groups, but with no consistent trend. ROC analysis showed that MCC in GLCM analysis had an area under the curve of 0.75.
ConclusionsOur study suggests that CTTA of ccRCC shows statistically significant textural differences in JPF surrounding high- versus low-grade ccRCC.
相似文献We aimed to explore the relationship among baseline perfusion CT parameters, clinical, and pathological factors with post-nephrectomy long-term progression-free survival in localized clear cell renal cell carcinoma.
Materials and methodsThis study retrospectively collected 127 patients from March 2005 to May 2007 who undertook perfusion CT. 61 patients were confirmed of pT1N0M0 or pT2N0M0 ccRCC. The mean follow-up time is 118.8 months (± 13.1 m, range 72–135 m). We compared clinical, pathological factors (gender, T stage, age, Fuhrmann grade, VEGF level, and MVD), and perfusion parameters before treatment [blood flow (BF), blood volume, mean transition time, and permeability surface-area product] between groups with post-nephrectomy metastasis and without metastasis. Association between covariates and progression-free survival (PFS) were analyzed using Cox proportional regression.
ResultsAmong 61 patients, 11 developed distant metastasis (10 in the lung, one in the bone). BF in metastatic group [429.1 (233.8, 570.1) ml/min/100 g] was significantly higher than non-metastatic group [214.3 (153.3, 376.5) ml/min/100 g] (p = 0.011). Metastatic group also had more patients with higher Fuhrmann grade. Multi-covariant Cox regression demonstrated T staging, Fuhrmann grade, and BF were significantly associated with PFS [hazard ratio (HR) 3.35, 3.08, and 1.006]. In another model, BF > 230 ml/min/100 g was associated with PFS (HR 12.90), along with T staging and Fuhrmann grade (HR 4.73, 3.69).
ConclusionBaseline tumor BF is a potential biomarker in prediction long-term metastasis of localized ccRCC and may help screening for higher risk localized ccRCC patients who need personalized surveillance strategy after nephrectomy.
相似文献To evaluate the diagnostic performance of superparamagnetic iron-oxide (SPIO)-enhanced diffusion-weighted image (DWI) for distinguishing an intrapancreatic accessory spleen from pancreatic tumors.
Materials and methodsTwenty-six cases of intrapancreatic accessory spleen and nine cases of pancreatic tail tumors [neuroendocrine tumor (n = 8) and pancreatic adenocarcinoma (n = 1)] were analyzed. Two blind reviewers retrospectively reviewed the SPIO-enhanced magnetic resonance imaging (MRI) scans. The lesion visibility grades were compared and the diagnostic performance of SPIO-enhanced DWI was compared to those of SPIO-enhanced T2WI and T2*WI with the use of a receiver operating characteristic (ROC) analysis.
ResultsThe grade of lesion visibility was the highest on DWI [mean ± standard deviation (SD): 2.8 ± 0.3] followed by T2WI (2.3 ± 0.7, p < 0.001) and T2*WI (2.1 ± 0.7, p < 0.0001). Reviewers 1 and 2 correctly characterized the presence or absence of SPIO uptake in 34 of 35 cases (97.1%) on DWI, 24 (68.6%) and 25 (71.4%) cases on T2WI, respectively, and 16 (45.7%) and 17 (48.6%) cases on T2*WI. The area under the ROC curve (AUC) of DWI was 0.974 and 0.989 for reviewers 1 and 2, respectively. For Reviewer 1, the AUC of DWI was significantly higher than that of T2*WI (0.756, p < 0.01), although it was not significantly different from that of T2WI (0.868, p = 0.0857). For Reviewer 2, the AUC of DWI was significantly higher than those of T2WI (0.846, p < 0.05) and T2*WI (0.803, p < 0.01).
ConclusionThe diagnostic performance of SPIO-enhanced DWI was better than those of SPIO-enhanced T2*WI and T2WI for the diagnosis of intrapancreatic accessory spleen.
相似文献Purpose
To evaluate the correlation between CT findings and histologic grade of small clear cell renal cell carcinoma (ccRCC).Methods
CT scans of 101 patients with small ccRCC were reviewed independently by two radiologists for tumor size, shape, margin, encapsulation, enhancement pattern, and visual relative enhancement. Enhancement patterns were defined according to the percentage of uniform enhancement [pattern 1, homogeneous (≥90%); pattern 2, relatively homogeneous (≥75 and <90%); and pattern 3, heterogeneous (<75%)]. Quantitative parameters representing attenuation and degree of enhancement were calculated. Histologic grade was classified as low (Fuhrman grade I or II) and high (Fuhrman grade III or IV). CT imaging variables were analyzed using univariate and multivariate analyses.Results
A total of 63 low-grade and 38 high-grade small ccRCCs were assessed. Low-grade tumors differed from high-grade tumors with respect to enhancement pattern 1 or 2 (p < 0.001 and p < 0.001), smaller size (p = 0.002 and p = 0.001), and lower attenuation on unenhanced scan (p < 0.001 and p = 0.008). In multivariate analysis, enhancement pattern 1 or 2 and low attenuation (≤30 HU) were identified as independent predictors of low-grade ccRCC. Accuracy derived from logistic regression analysis was 79.2% for reader 1 and 70.3% for reader 2.Conclusions
CT imaging features including tumor attenuation and enhancement pattern can be useful to predict the biologic behavior of small ccRCC for adequate treatment strategy.The purpose of the study was to determine if the ≥ 15 mm threshold currently used to define PIRADS 5 lesions is the optimal size threshold for predicting high likelihood of clinically significant (CS) cancers.
MaterialsThree hundred and fifty-eight lesions that may be changed from category 4 to 5 or vice versa on the basis of the size criterion (category 4: n = 288, category 5: n = 70) from 255 patients were evaluated. Kendall’s tau-b statistic accounting for inter-lesion correlation, generalized estimation equation logistic regression, and receiver operating curve analysis evaluated two lesion size-metrics (lesion diameter and relative lesion diameter—defined as lesion diameter/prostate volume) for ability to identify CS (Gleason grade ≥ 3 + 4) cancer at targeted biopsy. Optimal cut-points were identified using the Youden index. Analyses were performed for the whole prostate (WP) and zone-specific sub-cohorts of lesions in the peripheral and transition zones (PZ and TZ).
ResultsLesion diameter showed a modest correlation with Gleason grade (WP: τB = 0.21, p < 0.0001; PZ: τB = 0.13, p = 0.02; TZ: τB = 0.32, p = 0.001), and association with CS cancer detection (WP: AUC = 0.63, PZ: AUC = 0.59, TZ: AUC = 0.74). Empirically derived thresholds (WP: 14 mm, PZ: 13 mm, TZ: 16 mm) performed similarly to the current ≥ 15 mm standard. Lesion relative lesion diameter improved identification of CS cancers compared to lesion diameter alone (WP: τB = 0.30, PZ: τB = 0.24, TZ: τB = 0.42, all p < 0.0001). AUC also improved for WP and PZ lesions (WP: AUC = 0.70, PZ: AUC = 0.68, and TZ: AUC = 0.74).
ConclusionsThe current ≥ 15 mm diameter threshold is a reasonable delineator of PI-RADS category 4 and category 5 lesions in the absence of extraprostatic extension to predict CS cancers. Additionally, relative lesion diameter can improve identification of CS cancers and may serve as another option for distinguishing category 4 and 5 lesions.
相似文献To assess the diagnostic performance of the apparent diffusion coefficient (ADC) in predicting the Fuhrman nuclear grading of clear cell renal cell carcinomas (ccRCC).
Materials and methodsA total of 129 patients who underwent partial and radical nephrectomies with pathology-proven ccRCC were retrospectively evaluated. Histopathological characteristics and nuclear grades were analyzed. In addition, conventional magnetic resonance imaging (MRI) features were assessed in consensus by two radiologists to discriminate nuclear grading. ADC values were obtained from a region of interest (ROI) measurement in the ADC maps calculated from diffusion-weighted imaging (DWI) using b values of 50, 500, and 800 s/mm2. The threshold values for predicting and differentiating low-grade cancers (Fuhrman I–II) from high grade (Fuhrman III–IV) was obtained using binary logistic regression. The ADC cut-off value for differentiating low- and high-grade tumors was determined using classification analysis.
ResultsSignificant associations (P < 0.001) were found between nuclear grading, conventional MR features, and DWI. Hemorrhage, necrosis, perirenal fat invasion, enhancement homogeneity, and cystic component were identified as independent predictors of tumor grade. High-grade ccRCC had significantly lower mean ADC values compared to low-grade tumors. An ADC cut-off value of 1.6 × 10−3 mm2/s had an optimal predictive percentage of 65.5% for low-grade tumors above this threshold and 81% for high-grade ccRCC below this threshold. Overall predictive accuracy was 70.5%.
ConclusionThe addition of ADC values to a model based on MRI conventional features demonstrates increased sensitivity and high specificity improving the distinguishing accuracy between both high-grade and low-grade ccRCC.
相似文献To compare the diagnostic accuracies of MDCT and high-resolution MRI (HR-MRI) for regional nodal metastases with different short-axis diameter ranges in rectal cancer patients.
MethodsRectal adenocarcinoma patients who underwent both MDCT and HR-MRI before surgery were included. The maximum short-axis diameters of the nodes were measured, and were classified as benign or malignant on imaging findings. All of the nodes were subdivided as follows: ≤ 5 mm (Group A), > 5 mm and ≤ 10 mm (Group B) , and > 10 mm (Group C). The postoperative pathological reports were used as the standard, and the sensitivity, specificity, accuracy, ROC curve, and AUC value were calculated for each subgroup.
ResultsA total of 592 nodes were included in the node-to-node evaluation. In Group A, the specificity and accuracy of HR-MRI were significantly higher than those of MDCT (99.28% vs. 93.99%, P < 0.001; 95.78% vs. 89.56%, P = 0.010; respectively). In Group B, the specificity and accuracy of HR-MRI were also higher than those of MDCT (98.36% vs. 55.74%, P < 0.001; 80.45% vs. 66.17%, P < 0.001; respectively). For Groups A and B, the AUCs of MDCT were both 0.65, whereas those of HR-MRI were 0.76 and 0.82, respectively. In Group C, all nine malignant nodes were correctly diagnosed metastases on MDCT, whereas one was misjudged as benign on HR-MRI.
ConclusionsThe diagnostic value of HR-MRI is superior to that of MDCT, with higher specificity, accuracy, and AUC values for HR-MRI than for MDCT.
相似文献To evaluate semi-automated measurement of liver surface nodularity (LSN) on MDCT in a cause-specific cohort of patients with chronic hepatitis C virus infection (HCV) for identification of hepatic fibrosis (stages F0–4).
MethodsMDCT scans in patients with known HCV were evaluated with an independently validated, semi-automated LSN measurement tool. Consecutive LSN measurements along the anterior liver surface were performed to derive mean LSN scores. Scores were compared with METAVIR fibrosis stage (F0–4). Fibrosis stages F0–3 were based on biopsy results within 1 year of CT. Most patients with cirrhosis (F4) also had biopsy within 1 year; the remaining cases had unequivocal clinical/imaging evidence of cirrhosis and biopsy was not indicated.
Results288 patients (79F/209M; mean age, 49.7 years) with known HCV were stratified based on METAVIR fibrosis stage: F0 (n = 43), F1 (n = 29), F2 (n = 53), F3 (n = 37), and F4 (n = 126). LSN scores increased with increasing fibrosis (mean: F0 = 2.3 ± 0.2, F1 = 2.4 ± 0.3, F2 = 2.6 ± 0.5, F3 = 2.9 ± 0.6, F4 = 3.8 ± 1.0; p < 0.001). For identification of significant fibrosis (≥ F2), advanced fibrosis (≥ F3), and cirrhosis (≥ F4), the ROC AUCs were 0.88, 0.89, and 0.90, respectively. The sensitivity and specificity for significant fibrosis (≥ F2) using LSN threshold of 2.80 were 0.68 and 0.97; for advanced fibrosis (≥ F3; threshold = 2.77) were 0.83 and 0.85; and for cirrhosis (≥ F4, LSN threshold = 2.9) were 0.90 and 0.80.
ConclusionLiver surface nodularity assessment at MDCT allows for accurate discrimination of intermediate stages of hepatic fibrosis in a cause-specific cohort of patients with HCV, particularly at more advanced levels.
相似文献To compare dual-energy CT (DECT) iodine overlay images with renal mass protocol CT in the evaluation of polycystic kidneys with respect to reading time, diagnostic confidence, and detection of renal lesions that are not definitively benign.
MethodsFollowing IRB approval, portal venous phase dual-source DECT scans performed between September 2013 and February 2016 from 55 patients (mean age 67 ± 15 years, 31 male, 24 female) with polycystic kidneys (4 or more cysts) were included. For each patient, two image sets were created: (1) DECT post-processed iodine overlay images and (2) simulated renal mass protocol CT images (virtual noncontrast and mixed images). Two radiologists independently retrospectively reviewed both sets at separate time points, evaluating for the presence of lesions that were not definitively benign (enhancing lesions or Bosniak IIF cysts), as well as reading times and Likert scale diagnostic confidence ratings (scaled 1–5) for the presence of non-benign lesions. Reading times were compared with a t test, diagnostic confidence with a McNemar test, and lesion number detection with Cohen’s kappa test.
ResultsIodine overlay images were read faster (mean 55 ± 26 s) than renal mass protocol (mean 105 ± 51 s) (p < 0.001). Readers assigned the highest diagnostic confidence rating in 64% using iodine overlay series, compared to 17% using renal mass protocol (p < 0.0001). The proportion of patients with recorded lesions was not significantly different between methods (p = 0.62).
ConclusionsDECT improves lesion assessment in polycystic kidneys by decreasing reading times and increasing diagnostic confidence, without affecting lesion detection rates.
相似文献To investigate [11C]acetate PET-surrogate parameter of fatty acid synthase activity—as suitable tool for diagnosis and monitoring of liver steatosis.
MethodsIn this retrospective study, data were obtained from 83 prostatic carcinoma patients from 1/2008 to 1/2014. Mean HU was calculated from unenhanced CT of all patients from liver with liver HU less than 40 as threshold for liver steatosis. SUVmax of the liver and of the blood pool in thoracic aorta (as background for calculation of a liver/background ratio [SUVl/b]) was measured. t test was used with a P < 0.05 considered as statistically significant difference and ROC analysis was used for calculating specificity and sensitivity.
Results19/83 patients (20%) had diagnosis of hepatic steatosis according to CT. Uptake of [11C]acetate was significantly higher in patients with hepatic steatosis as compared to control group (SUVmax 7.96 ± 2.0 vs. 5.48 ± 2.3 [P < 0.001]). There was also a significant correlation between both SUVmax (r = − 0.52, P < 0.001) and SUVl/b (r = − 0.59, P < 0.001) with the density (HU) of the liver. In ROC analysis for detection of liver steatosis SUVmax (threshold: 5.86) had a sensitivity of 94% and specificity of 69% with an AUC of 0.81. Increasing body mass index is correlated with the severity of steatosis.
ConclusionWe showed for the first time that hepatic steatosis associates with increased [11C]acetate uptake. Also, severity of steatosis correlates with [11C]acetate uptake. [11C]acetate uptake PET seems promising for the assessment of liver steatosis.
相似文献To determine correlation of liver stiffness measured by MR Elastography (MRE) with biliary abnormalities on MR Cholangiopancreatography (MRCP) and MRI parenchymal features in patients with primary sclerosing cholangitis (PSC).
MethodsFifty-five patients with PSC who underwent MRI of the liver with MRCP and MRE were retrospectively evaluated. Two board-certified abdominal radiologists in agreement reviewed the MRI, MRCP, and MRE images. The biliary tree was evaluated for stricture, dilatation, wall enhancement, and thickening at segmental duct, right main duct, left main duct, and common bile duct levels. Liver parenchyma features including signal intensity on T2W and DWI, and hyperenhancement in arterial, portal venous, and delayed phase were evaluated in nine Couinaud liver segments. Atrophy or hypertrophy of segments, cirrhotic morphology, varices, and splenomegaly were scored as present or absent. Regions of interest were placed in each of the nine segments on stiffness maps wherever available and liver stiffness (LS) was recorded. Mean segmental LS, right lobar (V–VIII), left lobar (I–III, and IVA, IVB), and global LS (average of all segments) were calculated. Spearman rank correlation analysis was performed for significant correlation. Features with significant correlation were then analyzed for significant differences in mean LS. Multiple regression analysis of MRI and MRCP features was performed for significant correlation with elevated LS.
ResultsA total of 439/495 segments were evaluated and 56 segments not included in MRE slices were excluded for correlation analysis. Mean segmental LS correlated with the presence of strictures (r = 0.18, p < 0.001), T2W hyperintensity (r = 0.38, p < 0.001), DWI hyperintensity (r = 0.30, p < 0.001), and hyperenhancement of segment in all three phases. Mean LS of atrophic and hypertrophic segments were significantly higher than normal segments (7.07 ± 3.6 and 6.67 ± 3.26 vs. 5.1 ± 3.6 kPa, p < 0.001). In multiple regression analysis, only the presence of segmental strictures (p < 0.001), T2W hyperintensity (p = 0.01), and segmental hypertrophy (p < 0.001) were significantly associated with elevated segmental LS. Only left ductal stricture correlated with left lobe LS (r = 0.41, p = 0.018). Global LS correlated significantly with CBD stricture (r = 0.31, p = 0.02), number of segmental strictures (r = 0.28, p = 0.04), splenomegaly (r = 0.56, p < 0.001), and varices (r = 0.58, p < 0.001).
ConclusionIn PSC, there is low but positive correlation between segmental LS and segmental duct strictures. Segments with increased LS show T2 hyperintensity, DWI hyperintensity, and post-contrast hyperenhancement. Global liver stiffness shows a moderate correlation with number of segmental strictures and significantly correlates with spleen stiffness, splenomegaly, and varices.
相似文献IVIM-DW imaging has shown potential usefulness in the study of pancreatic lesions. Controversial results are available regarding the reliability of the measurements of IVIM-derived parameters. The aim of this study was to evaluate the reliability and the diagnostic potential of IVIM-derived parameters in differentiation among focal solid pancreatic lesions and normal pancreas (NP).
MethodsFifty-seven patients (34 carcinomas—PDACs, 18 neuroendocrine neoplasms—panNENs, and 5 autoimmune pancreatitis—AIP) and 50 subjects with NP underwent 1.5-T MR imaging including IVIM-DWI. Images were analyzed by two independent readers. Apparent diffusion coefficient (ADC), slow component of diffusion (D), incoherent microcirculation (Dp), and perfusion fraction (f) were calculated. Interobserver reliability was assessed with intraclass correlation coefficient (ICC). A Kruskal–Wallis H test with Steel–Dwass post hoc test was used for comparison. The diagnostic performance of each parameter was evaluated through receiver operating characteristic (ROC) curve analysis.
ResultsOverall interobserver agreement was excellent (ICC = 0.860, 0.937, 0.968, and 0.983 for ADC, D, Dp, and f). D, Dp, and f significantly differed among PDACs and panNENs (p = 0.002, < 0.001, and < 0.001), albeit without significant difference at the pairwise comparison of ROC curves (p = 0.08-0.74). Perfusion fraction was higher in AIP compared with PDACs (p = 0.024; AUC = 0.735). Dp and f were higher in panNENs compared with AIP (p = 0.029 and 0.023), without differences at ROC analysis (p = 0.07).
ConclusionsIVIM-derived parameters have excellent reliability and could help in differentiation among solid pancreatic lesions and NP.
相似文献Purpose
To investigate whether multiphasic multidetector computed tomography (MDCT) enhancement can help identify the gain of chromosome 20 in clear cell renal cell carcinomas (RCCs), a rare prognostically significant cytogenetic abnormality.Methods
With the Institutional Review Board approval, we queried our institution’s pathology database to derive a cohort of 52 cases of clear cell RCC with preoperative four-phase renal mass protocol MDCT and karyotypes of the resected specimens during a 10-year period. Each lesion was evaluated for absolute and relative (compared to contralateral normal renal cortex) attenuations in each phase. Relative attenuation was calculated as [(lesion attenuation ? cortex attenuation)/cortex attenuation] × 100. The absolute and relative attenuations were compared using t-tests.Results
Clear cell RCCs with the gain of 20 had significantly less nephrographic and excretory phase enhancement than clear cell RCCs without the gain of 20 (86.4 HU vs. 111.4 HU, p = 0.007; 70.0 HU vs. 89.4 HU, p = 0.003; respectively). Additionally, the relative nephrographic and excretory phase attenuations of clear cell RCCs with the gain of 20 were significantly less than that of clear cell RCCs without the gain of 20 (?52.7 vs. ?34.7, p = 0.002; ?44.9 vs. ?31.1, p = 0.005; respectively).Conclusion
Multiphasic MDCT enhancement may assist in identifying the gain of chromosome 20 in clear cell RCCs, if validated in a large prospective trial.To assess the usefulness of factors unique to NCCT for the prediction of ESWL outcomes in patients with pancreatic duct stones.
Materials and methodsWe retrospectively evaluated 148 patients with multiple PDS who had undergone ESWL therapy. All patients received an examination for NCCT both before and after ESWL. The following parameters were measured and recorded: patient characteristics including sex and age; NCCT parameters including mean stone length, mean stone volumes before and after ESWL, mean value of CT attenuation, standard deviation of CT attenuation, variation coefficient of CT attenuation, skin-to-stone distance, and pancreatic duct diameter; ESWL outcome indexes including stone clearance rate calculated using the formula \(\frac{V0 - V1}{V0} \times 100\%\), and the number of ESWL sessions. All patients were divided into groups based on their SCR: A group (SCR ≥ 90%), B group (SCR between 50% and 90%), and C group (SCR < 50%). Analysis of variance was used among the three groups to evaluate the potential predictors of SCR, and a receiver-operating curve was established to determine the optimal cutoff value.
ResultsANOVA analysis revealed that MSD was the only significant predictor for SCR (p < 0.05), and ROC indicated an optimal cutoff value of +1000.45 HU, with a sensitivity up to 78.0% and specificity of 48.6%. Stones with MSD lower than +1000.45 HU had higher SCR (69.3%) than that of higher-density ones (59.6%). Pearson correlation analysis and histogram indicated a significant positive correlation between ESWL No. and MSL (r = 0.536), MSD (r = 0.250), SDSD (r = 0.247), and PDD (r = 0.227), all values being p < 0.01.
ConclusionMSD is the optimal predictor of ESWL efficacy, and PDS with lower MSD had a better clearance rate with fewer fragmentation sessions.
相似文献To prospectively compare multidetector-row CT (MDCT) and MR imaging (MRI) in the assessment of the ablative margin (AM) and index tumor immediately after radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) and assess whether non-contrast MRI with limited sequences (T1- and T2-weighted imaging only) was superior to a conventional MDCT protocol.
MethodsA total of 33 consecutive patients with 42 HCCs were included in this study. Both MDCT and MR images were independently reviewed by two radiologists regarding the ability to visually discriminate between the AM and index tumor, and the AM status within ablation zones. The AM status was classified as AM-plus (AM completely surrounding the tumor), AM-zero (AM was partly discontinuous, without protrusion of the tumor), and AM-minus (AM was partly discontinuous, with protrusion of the tumor). During the follow-up period, the cumulative local tumor progression rates were analyzed using the Kaplan–Meier method and Cox proportional hazards model. To determine the added value of contrast-enhanced MR images, both reviewers separately evaluated the two sets (unenhanced and enhanced) of MR images.
ResultsVisual discrimination between the AM and index tumor was possible in four (9.5%) and 34 (81%) of the 42 ablation zones using MDCT and MRI, respectively (p < 0.001). Thirty-eight and four cases were classified as AM-plus and AM-zero on MDCT images, respectively, whereas the ablation zones were categorized as AM-plus (n = 32), AM-zero (n = 9), and AM-minus (n = 1) when examining the MR images. The cumulative incidence of local tumor progression was significantly lower in cases with AM-plus on MRI (p = 0.007). Contrast-enhanced MRI had no added value for the assessment of the AM and index tumor.
ConclusionMRI was superior to MDCT for the differential assessment of the AM and index tumor immediately after RF ablation for HCC. Non-contrast MRI was also superior to the conventional MDCT protocol.
相似文献Magnetic resonance imaging (MRI) sequences with conical k-space trajectories are able to decrease motion artifacts while achieving ultrashort echo times (UTE). We assessed the performance of free-breathing conical UTE MRI in the evaluation of the pediatric pelvis for suspected appendicitis.
MethodsOur retrospective review of 84 pediatric patients who underwent MRI for suspected appendicitis compared three contrast-enhanced sequences: free-breathing conical UTE, breath-hold three-dimensional (3D) spoiled gradient echo (BH-SPGR), and free-breathing high-resolution 3D SPGR (FB-SPGR). Two radiologists performed blinded and independent evaluations of each sequence for image quality (four point scale), anatomic delineation (four point scale), and diagnostic confidence (five point scale). Subsequently, the three sequences were directly compared for overall image quality (− 3 to + 3 scale). Scores were compared using Kruskal–Wallis and Wilcoxon signed-rank tests.
ResultsUTE demonstrated significantly better perceived signal-to-noise ratio (SNR) and fewer artifacts than BH-SPGR and FB-SPGR (means of 3.6 and 3.4, 3.4 and 3.2, 3.1 and 2.7, respectively; p < 0.0006). BH-SPGR and FB-SPGR demonstrated significantly better contrast than UTE (means of 3.6, 3.4, and 3.2, respectively; p < 0.03). In the remaining categories, UTE performed significantly better than FB-SPGR (p < 0.00001), while there was no statistical difference between UTE and BH-SPGR. Direct paired comparisons of overall image quality demonstrated the readers significantly preferred UTE over both BH-SPGR (mean + 0.5, p < 0.00001) and FB-SPGR (mean + 1.2, p < 0.00001).
ConclusionsIn the evaluation of suspected appendicitis, free-breathing conical UTE MRI performed better in the assessed metrics than FB-SPGR. When compared to BH-SPGR, UTE demonstrated superior perceived SNR and fewer artifacts.
相似文献