Search results for "Contrast media"
showing 10 items of 323 documents
Magnetic Resonance Imaging Surveillance for Vestibular Schwannoma After Microsurgical Resection Using a Retrosigmoid Transmeatal Approach.
2020
BACKGROUND Vestibular schwannoma (VS) is a benign, usually slow-growing tumor. The drawback of radical microsurgical VS resection is the increased likelihood of neurologic injury, forcing surgeons to leave a tumor remnant in some cases. We evaluated the prognostic value of magnetic resonance imaging (MRI) enhancement patterns to determine the risk of tumor regrowth. METHODS This clinical study included 30 patients (20 women and 10 men) with VS who underwent surgery via a retrosigmoid transmeatal approach. The extent of resection was assessed by MRI 6 months after surgery. Two subtypes of intracanalicular linear enhancement were defined: linear enhancement of the walls of the internal audito…
Multiple sclerosis: prevalence of the ‘central vein’ sign in white matter lesions on gadolinium-enhanced susceptibility-weighted images
2021
Aims To evaluate prospectively whether an intravenous gadolinium injection could improve the detection of the central vein sign on susceptibility-weighted imaging sequences obtained with a 1.5 T magnetic resonance scanner in patients with multiple sclerosis compared to unenhanced susceptibility-weighted images. Materials and methods This prospective, institution review board-approved study included 19 patients affected by multiple sclerosis (six men; 13 women; mean age 40.8 years, range 20–74 years). Patients had the relapsing–remitting clinical subtype in 95% of cases, and only one (5%) patient had the primary progressive clinical subtype of multiple sclerosis. T2-weighted images, fluid-at…
Adhesive Small Bowel Obstruction: Predictive Factors of Lack of Response in Conservative Management with Gastrografin
2015
<b><i>Background:</i></b> Gastrografin represents a useful tool in the diagnosis and management of adhesive small bowel obstruction (ASBO). The aim of this study is to identify variables with negative influence in nonoperative management with gastrografin. <b><i>Methods:</i></b> From August 2008 to March 2013, 223 consecutive patients with 235 episodes of ASBO were included and received gastrografin. A protocol for prospective data collection was developed. In order to explore factors related to the failure of nonoperative treatment, univariate and multivariate analysis were performed. <b><i>Results:</i></b> One hundred…
99mTc-Hexamethylpropylene Amineoxime Leukocyte Scintigraphy in Acute Pancreatitis: An Alternative to Contrast-Enhanced Computed Tomography?
2005
Contrast-enhanced computed tomography (CECT) is the most efficient imaging technique for the diagnosis and staging of acute pancreatitis (AP); its use, however, may be unfeasible in some patients as a consequence of the drawbacks of intravenous (IV) contrast material. The aim of this study was to test the utility of labeled leukocyte scintigraphy (LLS) as an alternative imaging technique to CECT for the staging of AP.Sixty-six patients with AP were prospectively studied. All patients underwent CECT and pancreatic LLS using (99m)Tc-hexamethylpropylene amineoxime as leukocyte label within a time interval of 2 days, in the early phase of AP. In addition, all patients had their serum C-reactive…
PANCREATIC CARCINOMA VERSUS CHRONIC FOCAL PANCREATITIS: CONTRAST-ENHANCED POWER DOPPLER ULTRASONOGRAPHY FINDINGS
2005
Background: We assessed the potential usefulness of contrast-enhanced power Doppler ultrasonography (US) for differentiating pancreatic carcinoma from chronic focal pancreatitis. Methods: Twenty-six consecutive patients with ductal carcinoma (n=16) and chronic focal pancreatitis (n=10) underwent power Doppler US examinations before and after intravenous injection of an air-based contrast agent (Levovist, Schering, Berlin, Germany). Final diagnosis was obtained by surgery in all patients. The following parameters before and after intravenous administration of contrast agent were evaluated for each lesion: number, morphology and course of the vessels within the lesion and time to maximum dete…
Acute extrahepatic infectious or inflammatory diseases are a cause of transient mosaic pattern on CT and MR imaging related to sinusoidal dilatation …
2015
To report the association of a mosaic enhancement pattern on contrast-enhanced CT or MR imaging and hepatic sinusoidal dilatation (SD) with acute inflammatory conditions affecting extrahepatic organs. From 2007 to 2012, patients with acute inflammatory diseases who underwent contrast-enhanced CT and/or MRI of the liver with a mosaic enhancement pattern were selected. Clinico-biological and other imaging features were collected at diagnosis and during follow-up. Sixteen patients were included (15 women, median age 27 years; range 18–68). Five women (33 %) were receiving oral contraceptives. Acute inflammatory diseases included pyelonephritis (n = 10), pancreatitis (n = 2), pneumonia (n = 1),…
Synchronous parenchymal renal tumors of different histology in the same kidney
2009
Background: Synchronous primary cortical tumors of different histology in the same kidney are rare. Preoperative awareness of this coexistence is important, since it can help in planning the surgical approach. Purpose: To describe the imaging findings observed in five patients with two parenchymal malignant tumors of different histology in the same kidney. Material and Methods: We reviewed the pathology reports of 381 patients operated for renal tumors from January 2000 to March 2007. The medical records of all patients with multiple, synchronous, primary lesions of different histology in the same kidney were reviewed with special attention to imaging findings and indications on the nature…
Focal nodular hyperplasia in normal and fatty liver: a qualitative and quantitative evaluation with contrast-enhanced ultrasound
2004
The aim of this study was to describe gray-scale appearance of liver parenchyma and focal nodular hyperplasia (FNH) by pulse inversion (PI) ultrasound (US) at baseline and after contrast agent administration in patients with normal and fatty liver. Sixteen consecutive patients (12 women, 4 men) with 29 previously diagnosed FNHs (15 of 29 located in normal liver and 14 of 29 in fatty liver) underwent PI US before and after SH U 508A (Levovist) injection. Signal intensity values were measured within the FNHs and the adjacent liver parenchyma in selected images. Baseline echogenicity of fatty liver was higher (15.19 +/- 2.90 dB +/- SD) than normal liver (10.91 +/- 3.15 dB +/- SD; p<0.001). Aft…
Characterization of benign hepatic tumors arising in fatty liver with SonoVue and pulse inversion US.
2007
Background: We describe the spectrum of contrast-enhancement patterns of benign hepatic tumors arising in fatty liver on contrast-enhanced ultrasound (US). Methods: Sixteen patients (12 women and four men) with 27 benign hepatic tumors (17 hemangiomas, eight focal nodular hyperplasias, and two hepatocellular adenomas) arising in fatty liver underwent baseline and pulse inversion US after administration of SonoVue. Two experienced radiologists evaluated baseline echogenicity and dynamic enhancement pattern of each lesion in comparison with adjacent liver parenchyma. Results: After administration of SonoVue, in the arterial phase 13 of 17 hemangiomas showed peripheral globular enhancement and…
Heterogeneous delayed enhancement of hepatic parenchyma after intravenous infusion of sonographic contrast agent: a new hypothesis
2007
Purpose. The aim of this paper was to report a heterogeneous latephase hepatic enhancement pattern observed after administration of a sonographic contrast agent and to present an aetiological hypothesis for the phenomenon. Materials and methods. A total of 1,729 (1,012 women and 717 men; age range 28–82; mean age 51) patients underwent contrastenhanced sonography of the liver. The examination was performed with a low mechanical index (MI <0.09) after injection of sulphur-hexafluoride-filled microbubbles, using different fonographic equipment and different contrast-specific algorithms. Results. Heterogeneous delayed liver enhancement was observed in six patients in the late phase (180 s), wi…