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Evaluation of the accuracy of gadobenate dimeglumine-enhanced MR imaging in the detection and characterization of focal liver lesions 总被引:8,自引:0,他引:8
Pirovano G Vanzulli A Marti-Bonmati L Grazioli L Manfredi R Greco A Holzknecht N Daldrup-Link HE Rummeny E Hamm B Arneson V Imperatori L Kirchin MA Spinazzi A 《AJR. American journal of roentgenology》2000,175(4):1111-1120
OBJECTIVE. We evaluated the extent to which hepatic lesion characterization and detection is improved by using gadobenate dimeglumine for enhancement of MR images. MATERIALS AND METHODS. Eighty-six patients were imaged before gadobenate dimeglumine administration, immediately after the 2 mL/sec bolus administration of a 0.05 mmol/kg dose (dynamic imaging), and at 60-120 min after the IV infusion at 10 mL/min of a further 0.05 nmol/kg dose (delayed imaging). The accuracy for lesion characterization was assessed for a total of 107 lesions. Sensitivity for lesion detection was assessed for a total of 149 lesions detected on either intra-operative sonography, iodized oil CT, CT during arterial portography, or follow-up contrast-enhanced CT as the gold standard. RESULTS. The accuracy in differentiating benign from malignant liver lesions increased from 75% and 82% (the findings of two observers) on unenhanced images alone, to 89% and 80% on dynamic images alone (p<0.001, p = 0.8), and to 90.7% when combining the unenhanced and dynamic image sets (p<0.001, p = 0.023). Delayed images did not further improve accuracy (90% and 91%; p = 0.002, p< 0.05). A similar trend was apparent in terms of accuracy for specific diagnosis: values ranged from 49% and 62% on unenhanced images alone, to 76% and 70% on combined unenhanced and dynamic images (p<0.001, p = 0.06), and to 75% and 70% on inclusion of delayed images (p<0.001, p = 0.12). The sensitivity for lesion detection increased from 77% and 81% on unenhanced images alone, to 87% and 85% on combined unenhanced and dynamic images (p = 0.001, p = 0.267), and to 92% and 89% when all images were considered (p<0.001, p = 0.01). CONCLUSION. Contrast-enhanced dynamic MR imaging with gadobenate dimeglumine significantly increases sensitivity and accuracy over unenhanced imaging for the characterization of focal hepatic lesions, and delayed MR imaging contributes to the improved detection of lesions. 相似文献
34.
Multifocal nodular fatty infiltration of the liver mimicking metastatic disease on CT: imaging findings and diagnosis using MR imaging 总被引:1,自引:0,他引:1
Kröncke TJ Taupitz M Kivelitz D Scheer I Daberkow U Rudolph B Hamm B 《European radiology》2000,10(7):1095-1100
The aim of this study was to describe the MR appearance of multifocal nodular fatty infiltration of the liver (MNFIL) using
T1-weighted in-phase (IP) and opposed-phase (OP) gradient-echo as well as T2-weighted turbo-spin-echo sequences with fat suppression
(FSTSE) and without (HASTE). Magnetic resonance imaging examinations at 1.5 T using T1-weighted IP and OP-GRE with fast low
angle shot (FLASH) technique, and T2-weighted FSTSE, T2-weighted HASTE of 137 patients undergoing evaluation for focal liver
lesions were reviewed. Five patients were identified in whom CT indicated metastatic disease; however, no liver malignancy
was finally proven. Diagnosis was confirmed by biopsy (n = 3), additional wedge resection (n = 1) or follow-up MRI 6–12 months later (n = 5). Regarding the identified five patients, the number of focal liver lesions was 2 (n = 2) and more than 20 (n = 3). The MR imaging characteristics were as follows: OP-image: markedly hypointense (n = 5); IP image: isointense (n = 2) or slightly hyperintense (n = 3); T2-weighted FSTSE-image: isointense (n = 5); T2-weighted HASTE image isointense (n = 1); slightly hyperintense (n = 4). On OP images all lesions were sharply demarcated and of almost spherical configuration (n = 5). Further evaluation by histology or follow-up MR imaging did not give evidence of malignancy in any case. Histology
revealed fatty infiltration of the liver parenchyma in three patients. Magnetic resonance follow-up showed complete resolution
in two patients and no change in three patients. Multifocal nodular fatty infiltration can simulate metastatic disease on
both CT and MR imaging. The combination of in-phase (IP) and opposed-phase (OP) gradient-echo imaging can reliably differentiate
MNFIL from metastatic disease.
Received: 15 September 1999 Revised: 3 February 2000; Accepted: 7 February 2000 相似文献
35.
Taupitz M Schnorr J Abramjuk C Wagner S Pilgrimm H Hünigen H Hamm B 《Journal of magnetic resonance imaging : JMRI》2000,12(6):905-911
The purpose of this study was to evaluate the signal enhancement characteristics of very small superparamagnetic iron oxide particles (VSOP)-C63, a new monomer-coated, iron oxide-based magnetic resonance (MR) blood pool contrast medium with a very small particle size and optimized physical properties. Equilibrium MR angiography (MRA) of rats (thoracic and abdominal vessels) was performed at 1.5 T with a three-dimensional gradient-recalled echo (3D GRE) technique (TR/TE 6.6/2.3 msec, flip angle 25 degrees ) before and after (every 3-5 minutes up to 50 minutes) i.v. injection of VSOP-C63 [dosages: 15, 30, 45, 60, 75, and 90 micromol Fe/kg; diameter: 8 nm; relaxivities at 0.47 T: R1 = 30 l/(mmol * s); R2 = 39 l/(mmol * s)]. First-pass MRA images (3D-GRE, TR/TE 4.5/1.7 msec, flip angle 25 degrees ) were obtained with 45 micromol Fe/kg VSOP-C63 in comparison with 0.2 mmol Gd/kg of gadolinium diethylene triamine pentaacetic acid (Gd DTPA; before and every 5 seconds p.i.). MRA (3D GRE, TR/TE 4.5/1.7 msec, flip angle 25 degrees) of coronary vessels in rabbits was performed after i.v. injection of 45 micromol Fe/kg of VSOP-C63. In rats maximal S/N ratio in thoracic and abdominal arteries directly after i.v. injection of VSOP-C63 was 25 +/- 1, 43 +/- 2, 49 +/- 4, 57 +/- 3, 64 +/- 3, and 63 +/- 3 for the different dosages. Blood half-life was dose dependent (15 +/- 2, 20 +/- 3, 29 +/- 6, 37 +/- 5, 61 +/- 16, and 86 +/- 21 minutes). At a dose of 30 micromol Fe/kg even small intrarenal arteries were sharply delineated. First-pass MRA showed no significant difference in the S/N ratio between Gd-DTPA (71.5 +/- 11.5) and VSOP-C63 (65.1 +/- 18. 3). The proximal segments of the coronary arteries in rabbits were clearly depicted at a dose of 45 micromol Fe/kg. The monomer-coated, iron oxide-based contrast medium VSOP-C63 exhibits favorable properties as a blood pool agent for both equilibrium and first-pass MRA. J. Magn. Reson. Imaging 2000;12:905-911. 相似文献
36.
OBJECTIVE: To assess whether patients from non-white ethnic groups wait longer than white patients for elective in-patient admissions at St Mary's Hospital in London. METHODS: Patients who came off the waiting list for an elective inpatient admission between 1 April 2000 and 31 March 2001 were selected. A multivariable log linear model was developed to assess geometric mean waiting times for Black, Asian, Other and Missing ethnic groups compared to the White group, adjusted for age, sex, urgency and distance. RESULTS: Caution is needed in interpreting results, as a large number of patients had no usable ethnic code. There was no strong evidence that waiting times for ethnic groups were systematically different than for the White group. However, there was some evidence that white patients waited longer for a coronary arteriography than patients in other ethnic groups. This was partially explained by age, sex, clinical urgency and residential distance from St Mary's. CONCLUSIONS: The large proportion of patients with no usable ethnic code, lack of robust methods for case-mix adjustment and multiple ethnic categories makes analysis methodologically difficult. Regular and informative analysis of ethnic coded data is a necessary step in improving the accuracy and completeness of coding. 相似文献
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38.
Martin Jonczyk Julius Chapiro Federico Collettini Dominik Geisel Dirk Schnapauff Florian Streitparth Thomas Schmidt Bernd Hamm Bernhard Gebauer Gero Wieners 《Journal of vascular and interventional radiology : JVIR》2017,28(10):1378-1385
Purpose
To evaluate detectability of hepatocellular carcinoma (HCC) using split-bolus cone-beam CT in intraindividual comparison between cone-beam CT and contrast-enhanced MR imaging.Materials and Methods
In a retrospective, single-center study, 28 patients with 85 HCC tumors were treated with transarterial chemoembolization between May 2015 and June 2016. All patients underwent arterial and hepatobiliary phase (HBP) MR imaging within 1 month before transarterial chemoembolization. Cone-beam CT images were acquired using a split-bolus contrast injection with 2 contrast injections and 1 cone-beam CT acquisition. Statistical analyses included Friedman 2-way analysis, Kendall coefficient of concordance, and Wilcoxon test. Tumor detectability was scored using a 5-point system (1 = best; 5 = worst) by 2 independent readers resulting in 170 evaluated tumors. Quantitative analysis included signal-to-noise and contrast-to-noise ratio and contrast measurements. P values < .05 were considered significant.Results
Better tumor detection was provided with split-bolus cone-beam CT (2.91/2.73) and HBP MR imaging (2.93/2.21) compared with arterial MR imaging (3.72/3.05; P < .001) without statistical difference between cone-beam CT and HBP MR imaging in terms of detectability (P = .154) and sensitivity for hypervascularized tumors. More tumors were identified on cone-beam CT (n = 121/170) than on arterial MR imaging (n = 94/170). Average contrast-to-noise ratio values of arterial and HBP MR imaging were higher than for cone-beam CT (7.79, 8.58, 4.43), whereas contrast values were higher for cone-beam CT than for MR imaging (0.11, 0.13, 0.97).Conclusions
Split-bolus cone-beam CT showed excellent detectability of HCC. Sensitivity is comparable to HBP MR imaging and better than arterial phase MR imaging. 相似文献39.
40.
Twenty-one patients with insulin-dependent diabetes mellitus received simultaneous renal and segmental pancreatic transplants. A retrospective analysis of 112 real-time ultrasound (US) images, 108 technetium-99m glucoheptonate scinti-scans, 55 computed tomography (CT) scans, and 11 cystograms was performed. Complications that were observed included pancreatic transplant rejection, pancreatitis, arteriovenous occlusions, hemorrhage, abscesses, and extravasation at the pancreaticocystostomy site. Scintigraphy is a sensitive indicator of normal transplant function but is non-specific when findings are abnormal. Real-time US aids in the differentiation of acute rejection from pancreatitis and arteriovenous occlusion. CT is helpful for evaluation of postoperative complications. Imaging may play an important role in the noninvasive management of pancreatic transplants. 相似文献