1,720,985 research outputs found
Diagnostic impact of digital tomosynthesis in oncologic patients with suspected pulmonary lesions on chest radiography
No full textObjectives To assess the actual diagnostic impact of digital tomosynthesis (DTS) in oncologic patients with suspected pulmonary lesions on chest radiography (CXR). Methods A total of 237 patients (135 male, 102 female; age, 70.8±10.4 years) with a known primary malignancy and suspected pulmonary lesion(s) on CXR and who underwent DTS were retrospectively identified. Two radiologists (experience, 10 and 15 years) analysed in consensus CXR and DTS images and proposed a diagnosis according to a confidence score: 1 or 2=definitely or probably benign pulmonary or
extrapulmonary lesion, or pseudolesion; 3=indeterminate; 4 or 5=probably or definitely pulmonary lesion. DTS findings were proven by CT (n=114 patients), CXR during follow-up (n=105) or histology (n=18). Results Final diagnoses included 77 pulmonary opacities, 26 pulmonary scars, 12 pleural lesions and 122 pulmonary pseudolesions. DTS vs CXR presented a higher (P<0.05) sensitivity (92 vs 15 %), specificity (91 vs 9 %), overall accuracy
(92 vs 12 %), and diagnostic confidence (area under ROC, 0.997 vs 0.619). Mean effective dose of CXR vs DTS was 0.06 vs 0.107 mSv (P<0.05).
Conclusions DTS improved diagnostic accuracy and confidence in comparison to CXR alone in oncologic patients with suspected pulmonary lesions on CXR with only a slight, though significant, increase in radiation dose
Bolus versus continuous infusion of microbubble contrast agent for liver ultrasound by using an automatic power injector in humans: A pilot study
No full textPurpose. To evaluate the feasibility of using continuous infusion, in comparison with bolus injection, of a sulfur hexafluoride–microbubble contrast
agent to prolong the duration of hepatic parenchymal enhancement in humans during sonographic examination. Methods. This pilot study was approved by our institution’s ethics committee. Ten patients (5 men and 5 women; mean age 6 SD, 65 6 10 years) each received two injections: a bolus injection (2 ml/s) and then continuous infusion (0.5 ml/min) of the contrast agent by using an automatic injector. Acquired cine clips were transferred to a personal computer, and the video intensity was quantified by dedicated software. Results. From the time of the first microbubble visualization in the scanning plane, maximal enhancement was reached in 6.3 6 0.94 seconds after bolus injection and in 13.9 6 1.44 seconds during continuous infusion (p 5 0.002, Wilcoxon’s test for paired data). Compared with bolus injection, continuous infusion prolonged the duration of contrast enhancement (4.3 minutes 6 42 seconds versus 7.3 minutes 6 40 seconds; p 5 0.002), although no statistically significant difference in maximal
enhancement was observed (45 6 18% for bolus injection and 396 6%for continuous infusion; p50.62). Conclusions. Continuous infusion of sulfur hexafluoride–filled microbubbles via an automatic power injector prolongs hepatic contrast enhancement without significantly modifying the maximal enhancement over that at baseline. These data, coming from a pilot study, can be used to design a larger study with adequate statistical power
The most appropriate time delay after microbubble contrast agent intravenous injection to maximize liver metastasis conspicuity on contrast-enhanced ultrasound
No full textPurpose: To identify the most appropriate time delay after microbubble contrast agent injection to maximize liver metastasis conspicuity on contrast-enhanced ultrasound (CEUS). Methods: Twenty-five consecutive patients (12 male and 13 female; age: 50 ± 13 years) with a known primary tumor and evidence of liver metastases on unenhanced ultrasound (US) underwent CEUS. CEUS consisted of continuous liver parenchyma scanning during arterial (15–35 s after microbubble injection), portal venous (40–120 s), and late phase (from 120 s up to microbubble disappearance). Subjective conspicuity index (ranging from 1 to 5) and objective conspicuity index (Ilesion–Iliver/Iliver, I = signal intensity) were calculated on reference frames selected on arterial phase and every 20 s on portal venous and late phase. Results: A total number of 40 liver metastases were identified after microbubble injection. The highest liver metastasis conspicuity was observed on early portal venous phase (40–60 s after microbubble injection) both on visual (mean subjective conspicuity index ± standard deviation [SD] = 4.36 ± 0.75, reader 1; 4.25 ± 0.65, reader 2) and quantitative analysis (mean objective conspicuity index ± SD = −0.99 ± 0.001). Conclusion: The early portal venous phase (40–60 s after microbubble injection) provides the best liver metastases' conspicuity after microbubble contrast agent injection
Early Predictors of the Long-term Response to Therapy in Patients With Crohn Disease Derived From a Time-Intensity Curve Analysis After Microbubble Contrast Agent Injection
No full textThe aim of this study was to identify early predictors of the long-term response to therapy in patients with Crohn disease (CD) from time-intensity curves obtained after microbubble injection
Bolus versus continuous infusion of microbubble contrast agent for liver ultrasound by using an automatic power injector in humans: A pilot study
No full textPurpose. To evaluate the feasibility of using continuous infusion, in comparison with bolus injection, of a sulfur hexafluoride–microbubble contrast
agent to prolong the duration of hepatic parenchymal enhancement in humans during sonographic examination. Methods. This pilot study was approved by our institution’s ethics committee. Ten patients (5 men and 5 women; mean age 6 SD, 65 6 10 years) each received two injections: a bolus injection (2 ml/s) and then continuous infusion (0.5 ml/min) of the contrast agent by using an automatic injector. Acquired cine clips were transferred to a personal computer, and the video intensity was quantified by dedicated software. Results. From the time of the first microbubble visualization in the scanning plane, maximal enhancement was reached in 6.3 6 0.94 seconds after bolus injection and in 13.9 6 1.44 seconds during continuous infusion (p 5 0.002, Wilcoxon’s test for paired data). Compared with bolus injection, continuous infusion prolonged the duration of contrast enhancement (4.3 minutes 6 42 seconds versus 7.3 minutes 6 40 seconds; p 5 0.002), although no statistically significant difference in maximal
enhancement was observed (45 6 18% for bolus injection and 396 6%for continuous infusion; p50.62). Conclusions. Continuous infusion of sulfur hexafluoride–filled microbubbles via an automatic power injector prolongs hepatic contrast enhancement without significantly modifying the maximal enhancement over that at baseline. These data, coming from a pilot study, can be used to design a larger study with adequate statistical power
Accuracy of Semi Automated Workflow in Reconstruction of CT Angiography prior to Transcatheter Aortic Valve Implant
No full textPredictors of intrahepatic cholangiocarcinoma in cirrhotic patients scanned by gadobenate dimeglumine-enhanced magnetic resonance imaging: Diagnostic accuracy and confidence
No full textObjective: To identify predictors of intrahepatic cholangiocarcinoma in cirrhotic patients scanned by gadobenate dimeglumine (Gd-BOPTA)-enhanced magnetic resonance (MR) imaging. Methods: Fifty cirrhotic patients with 120 nodules, including 10 mass-forming intrahepatic cholangiocarcinomas and two combined hepatocellular carcinoma-cholangiocarcinomas, were scanned by Gd-BOPTA-enhanced MR imaging. Results: T1 hypointensity [odds ratio (OR), 20.12], peripheral hyperintense rim at hepatic arterial phase (OR, 13.5), and iso-hyperintensity at hepatobiliary phase (OR 21.32) were found to be independent predictors of intrahepatic cholangiocarcinoma. Conclusions: T1 hypointensity, peripheral hyperintense rim at hepatic arterial phase, and iso-hyperintensity at hepatobiliary phase are independent predictors of intrahepatic cholangiocarcinoma diagnosis in patients with liver cirrhosis. © 2015 Elsevier Inc
Value of percent change in tumoral volume measured at T2-weighted and diffusion-weighted MRI to identify responders after neoadjuvant chemoradiation therapy in patients with locally advanced rectal carcinoma
No full textPurpose: To evaluate the percent change in tumoral volume measured at T2-weighted magnetic resonance imaging (T2WMRI) and diffusion-weighted (DWI) as a method to identify responders after chemo- and radiation therapy (CRT) in patients with locally advanced rectal carcinoma. Materials and Methods: Forty-five consecutive patients (mean age ± SD: 72 years ± 9.7; male/female = 24/21) with locally advanced rectal carcinoma underwent CRT followed by surgery. Each patient underwent T2WMRI and DWI at 1.5T before and 6 weeks after the completion of CRT. The percent change in tumoral volume before and 6 weeks after CRT was compared in patients classified as responders and nonresponders according to rectal cancer regression grade. Results: Twenty-five patients were classified as responders with either partial (n = 20) or complete response (n = 5), while 20 patients were classified as nonresponders due to stable disease (n = 18) or disease progression (n = 2). Responders vs. nonresponders differed in the percent change of tumoral volume at T2WMRI (−67% ± 26% vs. −29% ± 26%; P < 0.05) and DWI images (−72% ± 24% vs. −33% ± 28%; P < 0.05) with a cutoff ≤ −70% for T2WMRI (sensitivity = 69%, 95% confidence interval [CI]: 48−85%; specificity = 100%, 95% CI 81–100%) and ≤66% for DWI (sensitivity = 73%, 95% CI: 52–88%; specificity = 100%, 95% CI 81–100%). Conclusion: The percent change in tumoral volume at T2WMRI and DWI images can differentiate responders from nonresponders in patients with locally advanced rectal carcinoma after neoadjuvant CRT
Value of percent change in tumoral volume measured at T2-weighted and diffusion-weighted MRI to identify responders after neoadjuvant chemoradiation therapy in patients with locally advanced rectal carcinoma
No full textPurpose: To evaluate the percent change in tumoral volume measured at T2-weighted magnetic resonance imaging (T2WMRI) and diffusion-weighted (DWI) as a method to identify responders after chemo- and radiation therapy (CRT) in patients with locally advanced rectal carcinoma. Materials and Methods: Forty-five consecutive patients (mean age ± SD: 72 years ± 9.7; male/female = 24/21) with locally advanced rectal carcinoma underwent CRT followed by surgery. Each patient underwent T2WMRI and DWI at 1.5T before and 6 weeks after the completion of CRT. The percent change in tumoral volume before and 6 weeks after CRT was compared in patients classified as responders and nonresponders according to rectal cancer regression grade. Results: Twenty-five patients were classified as responders with either partial (n = 20) or complete response (n = 5), while 20 patients were classified as nonresponders due to stable disease (n = 18) or disease progression (n = 2). Responders vs. nonresponders differed in the percent change of tumoral volume at T2WMRI (−67% ± 26% vs. −29% ± 26%; P < 0.05) and DWI images (−72% ± 24% vs. −33% ± 28%; P < 0.05) with a cutoff ≤ −70% for T2WMRI (sensitivity = 69%, 95% confidence interval [CI]: 48−85%; specificity = 100%, 95% CI 81–100%) and ≤66% for DWI (sensitivity = 73%, 95% CI: 52–88%; specificity = 100%, 95% CI 81–100%). Conclusion: The percent change in tumoral volume at T2WMRI and DWI images can differentiate responders from nonresponders in patients with locally advanced rectal carcinoma after neoadjuvant CRT
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