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OBJECTIVE. The purpose of this study is to test the association between diffusion-weighted MRI and prostate cancer Gleason score at both biopsy and final pathologic analysis after radical prostatectomy. SUBJECTS AND METHODS. Patients with prostate cancer (n = 72) underwent diffusion-weighted MRI (b values, 0, 800, and 1600 s/mm(2)) with an endorectal coil. Apparent diffusion coefficient (ADC) and ADC ratio were obtained in normal and pathologic tissue and were correlated with transrectal ultrasound-guided biopsy (n = 72) and histopathologic (n = 39) Gleason scores using the ANOVA test. ADC accuracy was estimated using ROC curves. RESULTS. Lesions suspicious for prostate cancer were detected in 65 patients. The mean ADC was 1.47 and 0.87 × 10(-3) mm(2)/s for normal and pathologic tissue, respectively (p < 0.001). When we divided the population into four groups (normal tissue and biopsy Gleason scores of 6, 7, and 8-10), then the mean ADC value was 1.47, 0.96, 0.80, and 0.78 × 10(-3) mm(2)/s, respectively (p < 0.001). The ADC ratio decreased along with an increase in biopsy Gleason score (66.9%, 56.7%, and 51.5% for Gleason scores of 6, 7 and 8-10, respectively) (ANOVA, p = 0.003) and pathologic Gleason score (ANOVA, p < 0.001). ROC curves had an AUC of 0.94 and 0.86 for ADC and ADC ratio, respectively (p = 0.012 and 0.042, respectively). CONCLUSION. Decreasing ADC values may represent a strong risk factor of harboring a poorly differentiated prostate cancer, independently of biopsy characteristics.

Objective: Gadobutrol is an extracellular macrocyclic gadolinium chelate recently introduced in MRI, and it has already been used for cardiac late enhancement imaging; however, until now it has never been compared with gadopentetate dimeglumine. The purpose of our study was to compare 0.1 mmol/kg gadobutrol to 0.2 mmol/kg gadopentetate dimeglumine for the detection of myocardial late enhancement in the same group of patients., Subjects and Methods: This was an exploratory single-blind parallel group study comparing gadobutrol (0.1 mmol/kg) to gadopentetate dimeglumine (0.2 mmol/kg) in 20 adult patients scheduled for cardiac late enhancement MRI with gadopentetate dimeglumine and whose MR images showed late enhancement. MR images were acquired at 10, 15, and 20 minutes after peripheral injection of gadobutrol by using a 3D turbo field echo inversion recovery T1-weighted sequence. Volume and percentage of late enhancement, number of involved segments, late enhancement localization and pattern, and late enhancement signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between contrast agents., Results: Late enhancement was not significantly different with gadobutrol and gadopentetate dimeglumine both in terms of total volume of myocardium (mean ± SD, 37.8 ± 56.1 and 35.1 ± 46.7 cm(3), respectively; p = 0.33) and percentage of myocardial wall involvement (22.5% ± 19.1% and 22.0% ± 17.2%, respectively; p = 0.67). The number of segments involved was not different (138 with gadobutrol vs 134 with gadopentetate dimeglumine). Furthermore, SNR and CNR were not different (gadopentetate dimeglumine, 123.8 ± 82.9 and gadobutrol, 117.2 ± 88.6, p = 0.58 and gadopentetate dimeglumine, 96.2 ± 68.9 and gadobutrol, 88.4 ± 72.9, p = 0.53, respectively)., Conclusion: A single dose of gadobutrol seems to be as effective as a double dose of gadopentetate dimeglumine for the detection of late enhancement.

Objective: Takayasu arteritis is difficult to diagnose, and the evaluation of disease activity is even more challenging. Laboratory, clinical, and radiologic criteria are limited indicators of disease activity. Gadofosveset trisodium is a recently introduced intravascular contrast agent. In this study we sought to investigate a correlation between clinical activity and enhancement of vascular wall thickening in patients with Takayasu arteritis who underwent MR angiography with gadofosveset., Subjects and Methods: Twenty-three consecutively registered patients (21 women, two men) with Takayasu arteritis underwent MR angiography of the supraaortic trunks, aorta, and visceral vessels. Intravascular contrast medium was used to correlate thickened vessel wall enhancement with clinical criteria of disease activity. ECG-triggered black-blood first-pass high-resolution steady-state imaging was performed for all patients., Results: Before MR angiography, 14 patients were considered to have active disease. Heterogeneous structural involvement of the vascular tree was found. Twenty of 23 patients (87.0%) had supraaortic trunk involvement, including 12 of the 14 patients (85.7%) with active disease. Seventeen of the 23 patients (73.9%) had aortic and visceral vessel involvement, including 12 of the 14 patients (85.7%) with active disease. On steady state images in the active disease group, the mean signal-to-noise-ratio increased from 17.4 to 35.3 after gadofosveset injection (p > 0.0001), while in the nonactive disease group it increased from 52.8 to 69.6 (p = 0.08). A cutoff of 40% was best for differentiating active from inactive disease (sensitivity, 100%; specificity, 89%; positive predictive value, 92%; negative predictive value, 100%)., Conclusion: Use of intravascular contrast medium significantly increases the effectiveness of MR angiography in differentiating active and inactive disease.

Objective: Fabry's disease may be difficult to differentiate from symmetric hypertrophic cardiomyopathy. Our aim was to compare the myocardial location and distribution patterns of delayed enhancement between patients with Fabry's disease who are affected by symmetric myocardial hypertrophy and patients with symmetric hypertrophic cardiomyopathy in order to identify a specific sign to best differentiate the two diseases., Conclusion: Patients with Fabry's disease-related hypertrophy showed left ventricular (LV) delayed enhancement with a typical and consistently found pattern characterized by the involvement of the inferolateral basal or mid basal segments and a mesocardial distribution that spared the subendocardium. This pattern seems to be specific to Fabry's disease; in fact, patients with symmetric hypertrophic cardiomyopathy had variable locations and distributions of delayed enhancement. These observations may contribute to identifying Fabry's disease as a specific cause of symmetric hypertrophy.

Objective: The aims of this article are to present the main features of MRI of cardiomyopathy and to show selected images of cardiomyopathies., Conclusion: Cardiomyopathy is a frequent reason for cardiac MRI evaluation, which is now considered the most appropriate imaging technique for the diagnosis and follow-up of this wide range of myocardial diseases.

Objective: The objective of our study was to test dynamic MRI in evaluating mammographically detected suspicious microcalcifications., Materials and Methods: One hundred twelve patients with mammographically detected microcalcifications with BI-RADS category 5 (n = 78) or 4 (n = 34) lesions were studied at 17 centers a using 3D gradient-echo dynamic coronal technique (< or = 3 mm thickness) and 0.1 mmol/kg of gadoteridol. A pathologic sample was obtained in all cases. Agreement between the major diameter measured on mammography, MRI, or both and the major diameter measured at pathologic examination was calculated in 62 cases., Results: Of the 112 lesions, pathologic examination revealed 37 benign lesions, 33 ductal carcinoma in situ (DCIS), and 42 invasive carcinomas. The specificity of MRI for benign lesions was 68%. Considering the subgroups of calcifications alone and calcifications associated with masses, the specificity values became 79% and 33%, respectively. The sensitivity of MRI for DCIS was 79%. Analysis of the two subgroups showed sensitivity values of 68% for calcifications alone and of 1% for calcifications associated with masses. The sensitivity for invasive carcinomas was 93%. Analysis of the two subgroups showed sensitivity values to be 92% for calcifications alone and 94% for calcifications associated with masses. Considering the overall results, the sensitivity of MRI was 87%; specificity, 68%; positive predictive value, 84%; negative predictive value, 71%; and accuracy, 80%. Considering the subgroups of calcifications alone and calcifications associated with masses, the sensitivity values became 80% and 97%; the positive predictive values, 86% and 82%; the negative predictive values, 71% and 75% (95% confidence interval [CI], 0.19-0.99); and the accuracy values, 80% and 82% (95% CI, 0.66-0.92), respectively. An odds ratio (OR) of 13.54 (95% CI, 5.20-35.28) showed a raised risk of malignant breast tumor in subjects with positive MR examination of mammographically detected suspicious clusters of microcalcifications. The statistical analysis on each subgroup showed an OR of 15.07 (95% CI, 4.73-48.08) for calcifications alone and an OR of 14.00 (95% CI, 1.23-158.84) for calcifications associated with masses. Any significant improvement in the predictive ability of dynamic MRI depending on the extent of calcifications on mammography was not proved. Considering the 62 cases of proved malignancy with measured maximal diameter at pathologic examination, both mammography and MR examination seem to overestimate tumor extent., Conclusion: The not-perfect sensitivity of MRI (87%), when applying our interpretation criteria and imaging sequences, is a crucial point that prevents us from clinical use of MRI in the diagnosis of mammographically detected microcalcifications.

Objective: Our aim was to compare the effectiveness of mammography and MRI in the detection of multifocal, multicentric breast cancer., Subjects and Methods: Ninety patients with planned mastectomies (nine bilateral) underwent mammography and dynamic gadolinium-enhanced MRI. Off-site reviewers aware of the entry criterion (planned mastectomy) evaluated both examinations for the presence of malignant foci, recording the density pattern on mammography. The gold standard was pathologic examination of the whole excised breast (slice thickness, 5 mm)., Results: Of 99 breasts, pathologic findings revealed 52 unifocal, 29 multifocal, and 18 multicentric cancers for a total of 188 malignant foci (158 invasive and 30 in situ). Overall sensitivity was 66% (124/188) for mammography and 81% (152/188) for MRI (p < 0.001); 72% (113/158) and 89% (140/158) for invasive foci (p < 0.001); and 37% (11/30) and 40% (12/30) for in situ foci (p > 0.05, not significant), respectively. Mammography and MRI missed 64 and 36 malignant foci, respectively, with median diameters of 8 and 5 mm (p = 0.033) and an invasive-noninvasive ratio of 2.4:1 (45:19) and 1.0:1 (18:18) (p = 0.043), respectively. The overall positive predictive value (PPV) was 76% (124/164) for mammography and 68% (152/222) for MRI (not significant). In breasts with an almost entirely fatty pattern, sensitivity was 75% for mammography and 80% for MRI (not significant), and the PPV was 73% and 65% (not significant), respectively. In breasts with fibroglandular or dense pattern, the sensitivity was 60% and 81% (p < 0.001), and the PPV was 78% and 71% (not significant), respectively., Conclusion: MRI was more sensitive than mammography for the detection of multiple malignant foci in fibroglandular or dense breasts. Mammography missed larger and more invasive cancer foci than MRI. A relatively low PPV was a problem for both techniques.

Objective: The purposes of the study were to evaluate the complications of patients who underwent percutaneous transaxillary implantation of a permanent catheter-port system for intraarterial hepatic chemotherapy and determine their clinical relevance and specific management. SUBJECTS AND METHODS. Catheter-port systems were placed in 204 patients with liver tumors (86.7% from colorectal metastases). Under sonographic and fluoroscopic guidance, a 5.8-French catheter was placed in the hepatic artery and connected to a subcutaneous reservoir after embolization of the gastroduodenal and right gastric arteries. Floxuridine plus dexamethasone and systemic low-dose heparin were administered. During the follow-up period, complications were classified as clinically not significant (type 1), clinically significant not requiring interruption of intrahepatic chemotherapy (type 2), clinically significant needing temporary suppression of intrahepatic chemotherapy (type 3), and clinically significant causing permanent suppression of intrahepatic chemotherapy (type 4)., Results: No complications occurred during the implantation procedures. The mean number of intrahepatic chemotherapy cycles was 8.1. The mean follow-up period was 270 days. Primary and secondary patency rates of the system were 71.6% and 91.2%, respectively. Temporary suppression of intrahepatic chemotherapy was necessary in 19.6% of the patients and definitive suppression, in 8.8%. Hepatic artery thrombosis, not recanalized by local thrombolysis, was the main cause of permanent intrahepatic chemotherapy interruption (4.4%). Catheter occlusions and cerebral complications were not observed. In 91.2% of the patients, intrahepatic chemotherapy could be completed., Conclusion: Percutaneous implantation of a removable and reimplantable catheter-port system for intrahepatic chemotherapy can be a safe procedure to treat unresectable liver metastases from colorectal cancer. Technical and pharmacologic complications with variable clinical relevance occurred, and various specific management strategies were necessary to reduce their incidence.

Objective: This study was conducted to determine the efficacy and safety of four different doses of gadobenate dimeglumine for contrast-enhanced three-dimensional MR angiography of the abdominal aorta and renal arteries., Subjects and Methods: Ninety-four patients with suspected abnormality of the abdominal aorta or renal arteries underwent unenhanced three-dimensional gradient-recalled echo time-of-flight MR angiography and contrast-enhanced MR angiography after the IV injection of one of four doses of gadobenate dimeglumine (0.025, 0.05, 0.1, and 0.2 mmol/kg of body weight). Efficacy was assessed on-site and by two blinded off-site reviewers in terms of change in total diagnostic quality score and diagnostic quality score per vessel segment from baseline unenhanced time-of-flight MR angiography to contrast-enhanced MR angiography. Secondary efficacy end points included lesion count and level of confidence in lesion characterization. Safety assessments comprised adverse event monitoring, physical evaluation, vital signs, ECG, and laboratory investigations., Results: A significant change in the total diagnostic quality score from unenhanced to contrast-enhanced MR angiography was observed at all doses. The change increased with increased dose, plateauing at the 0.1 mmol/kg dose level. More patients with lesions detected and increased reviewer confidence for lesion characterization were noted on contrast-enhanced MR angiography compared with unenhanced MR angiography, although no dose-related trends were observed. All doses were well tolerated, and no significant changes in safety parameters were observed., Conclusion: Gadobenate dimeglumine is an effective and safe agent for contrast-enhanced MR angiography of the abdominal aorta and renal arteries. A dose of 0.1 mmol/kg of body weight appears to be the most suitable.