BACKGROUND/AIMS: The therapeutic effect of transarterial chemoembolization (TACE) against hepatocellular carcinoma (HCC) is usually assessed using multidetector computed tomography (MDCT). However, dense lipiodol depositions can mask the enhancement of viable HCC tissue in MDCT. Contrast-enhanced ultrasonography (CEUS) could be effective in detecting small areas of viability and patency in vessels. We investigated whether arterial enhancement in CEUS after treatment with TACE can be used to detect HCC viability earlier than when using MDCT. METHODS: Twelve patients received CEUS, MDCT, and gadoxetic-acid-enhanced dynamic magnetic resonance imaging (MRI) at baseline and 4 and 12 weeks after TACE. The definition of viable HCC was defined as MRI positivity after 4 or 12 weeks. RESULTS: Eight of the 12 patients showed MRI positivity at 4 or 12 weeks. All patients with positive CEUS findings at 4 weeks (n=8) showed MRI positivity and residual viable HCC at 4 or 12 weeks. Five of the eight patients with positive CEUS findings at 4 weeks had negative results on the 4-week MDCT scan. Four (50%) of these eight patients did not have MRI positivity at 4 weeks and were ultimately confirmed as having residual HCC tissue at the 12-week MRI. Kappa statistics revealed near-perfect agreement between CEUS and MRI (kappa=1.00) and substantial agreement between MDCT and MRI (kappa=0.67). CONCLUSIONS: In the assessment of the response to TACE, CEUS at 4 weeks showed excellent results for detecting residual viable HCC, which suggests that CEUS can be used as an early additive diagnosis tool when deciding early additional treatment with TACE.
Aged ; Aged, 80 and over ; Antineoplastic Agents/administration & dosage ; Carcinoma, Hepatocellular/pathology/therapy/*ultrasonography ; Chemoembolization, Therapeutic ; Contrast Media/*chemistry ; Female ; Gadolinium DTPA/chemistry ; Humans ; Liver Neoplasms/pathology/therapy/*ultrasonography ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Pilot Projects ; Tomography, X-Ray Computed ; Treatment Outcome

OBJECTIVE: To compare gadoxetic acid injection rates of 0.5 mL/s and 1 mL/s for hepatic arterial-phase magnetic resonance (MR) imaging. MATERIALS AND METHODS: In this prospective study, 101 consecutive patients with suspected focal liver lesions were included and randomly divided into two groups. Each group underwent dynamic liver MR imaging using a 3.0-T scanner after an intravenous injection of gadoxetic acid at rates of either 0.5 mL/s (n = 50) or 1 mL/s (n = 51). Arterial phase images were analyzed after blinding the injection rates. The signal-to-noise ratios (SNRs) of the liver, aorta, portal vein, hepatic vein, spleen, and pancreas were measured. The contrast-to-noise ratios (CNRs) of the hepatocellular carcinomas (HCC) were calculated. Finally, two experienced radiologists were independently asked to identify, if any, HCCs in the liver on the images and score the image quality in terms of the presence of artifacts and the proper enhancement of the liver, aorta, portal vein, hepatic vein, hepatic artery, spleen, pancreas, and kidney. RESULTS: The SNRs were not significantly different between the groups (p = 0.233-0.965). The CNRs of the HCCs were not significantly different (p = 0.597). The sensitivity for HCC detection and the image quality scores were not significantly different between the two injection rates (p = 0.082-1.000). CONCLUSION: Image quality and sensitivity for hepatic HCCs of arterial-phase gadoxetic acid-enhanced MR were not significantly improved by reducing the contrast injection rate to 0.5 mL/s compared with 1 mL/s.
Adult ; Aged ; Aged, 80 and over ; Artifacts ; Carcinoma, Hepatocellular/*radiography ; Contrast Media/*administration & dosage/*diagnostic use ; Dose-Response Relationship, Drug ; Female ; Gadolinium DTPA/*administration & dosage/*diagnostic use ; Hepatic Artery ; Humans ; Liver Neoplasms/*radiography ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Prospective Studies ; Sensitivity and Specificity ; Signal-To-Noise Ratio

OBJECTIVE: Clear depiction of the common bile duct is important when evaluating neonatal cholestasis in order to differentiate biliary atresia from other diseases. During MR cholangiopancreatography, the T2-shortening effect of gadolinium can increase the contrast-to-noise ratio (CNR) of the bile duct and enhance its depiction. The purpose of this study was to confirm, by performing a phantom study, the T2-shortening effect of gadolinium, to evaluate the effect of different gadolinium chelates with different gadolinium concentrations and different magnetic field strengths for investigating the optimal combination of these conditions, and for identifying the maximum CNR for the evaluation of the biliary system. MATERIALS AND METHODS: MR imaging using a T2-weighted single-shot fast spin echo sequence and T2 relaxometry was performed with a sponge phantom in a syringe tube. Two kinds of contrast agents (Gd-DTPA and Gd-EOB-DTPA) with different gadolinium concentrations were evaluated with 1.5T and 3T scanners. The signal intensities, the CNRs and the T2 relaxation time were analyzed. RESULTS: The signal intensities significantly decreased as the gadolinium concentrations increased (p < 0.001) with both contrast agents. These signal intensities were higher on a 3T (p < 0.001) scanner. The CNRs were higher on a 1.5T (p < 0.001) scanner and they showed no significant change with different gadolinium concentrations. The T2 relaxation time also showed a negative correlation with the gadolinium concentrations (p < 0.001) and the CNRs showed decrease more with Gd-EOB-DTPA (versus Gd-DTPA; p < 0.001) on a 3T scanner (versus 1.5T; p < 0.001). CONCLUSION: A T2-shortening effect of gadolinium exhibits a negative correlation with the gadolinium concentration for both the signal intensities and the T2 relaxation time. A higher CNR can be obtained with Gd-DTPA on a 1.5T MRI scanner.
Analysis of Variance ; Biliary Atresia/diagnosis ; Cholangiopancreatography, Magnetic Resonance/*methods ; Cholestasis/diagnosis ; Contrast Media/*administration & dosage/diagnostic use ; Diagnosis, Differential ; Gadolinium DTPA/*administration & dosage/diagnostic use ; Humans ; Image Processing, Computer-Assisted ; Linear Models ; *Phantoms, Imaging

PURPOSE: To assess the frequency and severity of acute adverse reactions to intravenous administration of gadolinium-based contrast agents using computerized reporting system at a single large academic institution. MATERIALS AND METHODS: We assessed data from electronic hospital information system from October 2008 to December 2010. Reactions were classified as mild, moderate, or severe. We compared the frequency of adverse reactions among three contrast agents (Gd-BT-DO3A, Gd-DTPA and Gd-EOB-DTPA). RESULTS: The total number of administrated contrast agents was 33,600, and the number of administration of Gd-BT-DO3A, Gd-DTPA and Gd-EOB-DTPA were 20,824 (62%), 10,417 (31%) and 2,359 (7%), respectively. Total 39 adverse reactions were reported accounting for 0.1161% of all administrations. The incidences of adverse reactions were 0.1248% (26/39, 67%) for Gd-BT-DO3A, 0.0768% (8/39, 21%) for Gd-DTPA, and 0.2120% (5/39, 13%) for Gd-EOB-DTPA. The difference of frequencies of adverse reaction among three contrast agents was not significant. Most cases of the adverse effect were mild (35/39, 89.7%). Moderate and severe adverse reactions were encountered in two patients, respectively. CONCLUSION: Among Koreans, adverse effects were rare, and especially, moderate to severe adverse reactions were much rarer. There was no difference among the frequencies of adverse reactions caused by three different contrast agents.
Accounting ; Administration, Intravenous ; Contrast Media ; Electronics ; Electrons ; Gadolinium DTPA ; Hospital Information Systems ; Humans ; Incidence ; Retrospective Studies

OBJECTIVE: We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. MATERIALS AND METHODS: One hundred and sixty-eight patients (64 +/- 9 years) received adenosine (140 microg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. RESULTS: In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 +/- 11.7 versus 82.4 +/- 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 +/- 1.9% versus 97 +/- 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 +/- 24.0 versus 140.9 +/- 25.7 mmHg; diastolic: 80.2 +/- 12.5 mmHg versus 78.9 +/- 15.6, respectively). CONCLUSION: This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging.
Adenosine/administration & dosage/*adverse effects ; Adult ; Aged ; Aged, 80 and over ; Blood Pressure/drug effects ; Contrast Media/diagnostic use ; Coronary Disease/*diagnosis ; Female ; Gadolinium DTPA/diagnostic use ; Heart Rate/drug effects ; Hemodynamics ; Humans ; Infusions, Intravenous ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Oxygen/blood ; Prospective Studies ; Vasodilator Agents/administration & dosage/*adverse effects

This study examined the corneal permeability of topical eye drop solutions added with various corneal penetrating accelerators and gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) by nuclear magnetic resonance imaging (MRI). Twenty-four New Zealand rabbits were randomly divided into 3 groups according to the random digits table: Gd-DTPA group, in which the rabbits received 23.45% Gd-DTPA; hyaluronic acid group, in which 23.45% Gd-DTPA plus 0.2% hyaluronic acid was administered; azone group, in which 23.45% Gd-DTPA with 0.2% azone was given. Fifty microliters of the eye drops was instilled into the conjunctive sac every 5 min, for a total of 6 applications in each group. Contrast medium signals in the cornea, anterior chamber, posterior chamber, and vitreous body were scanned successively by MRI. The morphology and cell density of the corneal endothelium were examined before and 24 h after the treatment. The results showed that the residence time of Gd-DTPA in the conjunctival sac in the hyaluronic acid and azone groups was longer than that in the Gd-DTPA group. The signals in the anterior chamber of the Gd-DTPA and hyaluronic acid groups were increased slightly, and those in the azone group strengthened sharply. The signal intensity continuously rose over 80 min before reaching plateau. The strengthening rate of signals in the anterior chamber was 19.63% in the Gd-DTPA group, 53.42% in the sodium hyaluronate group, and 226.94% in the azone group. No signal was detected in the posterior chamber or vitreous body in all the 3 groups. Corneal morphology and cell density did not show any significant changes after the treatment in all the 3 groups. It was concluded that azone can significantly improve the corneal permeability of drugs that are similar to Gd-DTPA in molecular weight and molecular size, and MRI is a noninvasive technique that can dynamically detect eye drop metabolism in real time.
Animals ; Azepines ; administration & dosage ; pharmacokinetics ; Contrast Media ; administration & dosage ; pharmacokinetics ; Cornea ; metabolism ; Female ; Gadolinium DTPA ; administration & dosage ; pharmacokinetics ; Magnetic Resonance Imaging ; Male ; Ophthalmic Solutions ; Permeability ; Rabbits

The intravenous administration of gadopentetate dimeglumine (GD) is relatively safe and rarely causes systemic toxicity in the course of routine imaging studies. However, the general safety of intrathecal GD has not been established. We report a very rare case of an overdose intrathecal GD injection presenting with neurotoxic manifestations, including a decreased level of consciousness, global aphasia, rigidity, and visual disturbance.
Adult ; Aphasia/etiology/pathology/physiopathology ; Brain/drug effects/pathology ; *Contrast Media/administration & dosage/toxicity ; *Gadolinium DTPA/administration & dosage/toxicity ; Humans ; *Injections, Spinal ; Male ; Muscle Rigidity/etiology/pathology/physiopathology ; *Neurotoxicity Syndromes/etiology/pathology/physiopathology ; Tomography, X-Ray Computed ; Vision Disorders/etiology/pathology

OBJECTIVE: To determine if a combination of ferucarbotran-enhanced T2*weighted-gradient echo (T2*W-GRE) and T2-weighted turbo spin echo (T2W-TSE) images in gadolinium- and ferucarbotran-enhanced MRI has additive efficacy compared to each image alone for detecting small (< or = 2.0 cm) hepatocellular carcinoma (HCC) lesions in a group of cirrhotic patients and metastases in a group of non-cirrhotic patients. MATERIALS AND METHODS: Two readers retrospectively analyzed gadolinium- and ferucarbotran-enhanced T2*W-GRE, T2W-TSE, and combined T2*W-GRE/T2W-TSE images of 119 patients with 157 HCCs and 32 patients with 98 metastases. The diagnostic accuracy and sensitivity for each image set and the combined set were evaluated using the alternative-free response receiver operating characteristic method. RESULTS: The mean area under the curve value of the combined set (0.966) tended to be better than that for each individual image set (T2W-TSE [0.910], T2*W-GRE [0.892]). Sensitivities in the combined set were higher than those in each individual image set for detecting HCC (mean, 93.0% versus 81.6% and 86.7%, respectively, p < 0.01). Sensitivities in the combined set and the T2W-TSE set were the same for detecting metastases, and both were higher than the sensitivity seen in the T2*W-GRE set (mean, 97.5% versus 85.2 %, p < 0.01). CONCLUSION: Combining ferucarbotran-enhanced T2*W-GRE and T2W-TSE has additive efficacy for detecting HCC in cirrhotic patients, but T2W-TSE is preferred for detecting metastases in non-cirrhotic patients.
Adult ; Aged ; Carcinoma, Hepatocellular/*diagnosis ; Contrast Media/*administration & dosage ; Female ; Gadolinium DTPA/*diagnostic use ; Humans ; Iron/*diagnostic use ; Liver Neoplasms/*diagnosis/secondary ; *Magnetic Resonance Imaging/methods ; Male ; Middle Aged ; Observer Variation ; Oxides/*diagnostic use ; Predictive Value of Tests ; Sensitivity and Specificity

OBJECTIVE: We wanted to evaluate the role of diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC) for detecting breast tumors, as compared with the T1- and T2-weighted images. MATERIALS AND METHODS: Forty-one female patients underwent breast MRI, and this included the T1-, T2-, DWI and dynamic contrast-enhanced images. Sixty-five enhancing lesions were detected on the dynamic contrast-enhanced images and we used this as a reference image for detecting tumor. Fifty-six breast lesions were detected on DWI and the histological diagnoses were as follows: 43 invasive ductal carcinomas, one mucinous carcinoma, one mixed infiltrative and mucinous carcinoma, seven ductal carcinomas in situ (DCIS), and four benign tumors. First, we compared the detectability of breast lesions on DWI with that of the T1- and T2-weighted images. We then compared the ADCs of the malignant and benign breast lesions to the ADCs of the normal fibroglandular tissue. RESULTS: Fifty-six lesions were detected via DWI (detectability of 86.2%). The detectabilities of breast lesions on the T1- and T2-weighted imaging were 61.5% (40/65) and 75.4% (49/65), respectively. The mean ADCs of the invasive ductal carcinoma (0.89 +/- 0.18x10(-3)mm2/second) and DCIS (1.17 +/- 0.18x10(-3)mm2/ second) are significantly lower than those of the benign lesions (1.41 +/- 0.56x10(-3)mm2/second) and the normal fibroglandular tissue (1.51 +/- 0.29x10(-3)mm2/ second). CONCLUSION: DWI has a high sensitivity for detecting breast tumors, and especially for detecting malignant breast tumors. DWI was an effective imaging technique for detecting breast lesions, as compared to using the T1- and T2-weighted images.
Adenocarcinoma, Mucinous/*diagnosis ; Adult ; Aged ; Breast/pathology ; Breast Neoplasms/*diagnosis ; Carcinoma, Ductal, Breast/*diagnosis ; Carcinoma, Intraductal, Noninfiltrating/*diagnosis ; Contrast Media/administration & dosage ; Diffusion Magnetic Resonance Imaging/*methods ; Female ; Gadolinium DTPA/diagnostic use ; Humans ; Image Enhancement/methods ; Imaging, Three-Dimensional/methods ; Middle Aged ; Observer Variation ; Sensitivity and Specificity

OBJECTIVE: We wanted to investigate the ability of breast MR imaging to identify the primary malignancy in patients with axillary lymph node metastases and initially negative mammography and sonography, and we correlated those results with the conventional imaging. MATERIALS AND METHODS: From September 2001 to April 2006, 12 patients with axillary lymph node metastases and initially negative mammography and sonography underwent breast MR imaging to identify occult breast carcinoma. We analyzed the findings of the MR imaging, the MR-correlated mammography and the second-look sonography. We followed up both the MR-positive and MR-negative patients. RESULTS: MR imaging detected occult breast carcinoma in 10 of 12 (83%) patients. Two MR-negative patients were free of carcinoma in the ipsilateral breast during their follow-up period (39 and 44 months, respectively). In nine out of 10 patients, the MR-correlated mammography and second-look sonography localized lesions that were not detected on the initial exam. All the non-MR-correlated sonographic abnormalities were benign. CONCLUSION: Breast MR imaging can identify otherwise occult breast cancer in patients with metastatic axillary lymph nodes. Localization of the lesions through MR-correlated mammography and second-look sonography is practically feasible in most cases.
Adenocarcinoma/*diagnosis ; Adult ; Aged ; Axilla ; Biopsy ; Breast/pathology ; Breast Neoplasms/*diagnosis/secondary ; Contrast Media/administration & dosage ; Feasibility Studies ; Female ; Follow-Up Studies ; Gadolinium DTPA/diagnostic use ; Humans ; Image Processing, Computer-Assisted ; Lymph Nodes/*pathology ; Lymphatic Metastasis/diagnosis ; Lymphoma, Large B-Cell, Diffuse/*diagnosis ; Magnetic Resonance Imaging/*methods ; Mammography/*methods ; Middle Aged ; Neoplasms, Unknown Primary/*diagnosis ; Ultrasonography, Mammary/*methods