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Background Breast magnetic resonance imaging (MRI) is extremely sensitive for detecting lesions, but certain characteristics of malignancies, such as the washout pattern of kinetic curves, are not specific. Correlations of false-positive MRI and specific pathological results are worthy of study. Methods From March 2008 to September 2011, 217 cases received biopsy after dedicated breast MRI in our department. Biopsies were recommended for suspected malignancies based on the overall analysis of early subtracted phase images, postenhanced curve patterns, color mapping, and tumor morphology. Results Twenty-nine percent of cases were false positive for malignancy, according to MRI. These lesions included radial scar, apocrine metaplasia, atypical ductal hyperplasia, sclerosing adenosis, intraductal papilloma, fibrocystic change, and mastitis. Conclusion The ability of tumor cells to induce vascularization occurs early in the cell transformation process; therefore, premalignant breast lesions may also induce vascularization to facilitate malignant transformation. As a noninvasive method, contrast-enhanced MRI has a potential role in estimating the degree of angiogenesis and tumor microvascular permeability of breast neoplasms.

Objective This study was to investigate the usefulness and limitations of cardiac magnetic resonance imaging (MRI). We compared echocardiography (ECHO) and perfusion scans to evaluate: left ventricular wall scar formation of the myocardium; hypokinesis, akinesis, or dyskinesis of the myocardium; regurgitation of the aortic and mitral valves; post acute myocardial infarction (AMI) ventricular function; and the viable myocardium (ischemia/infarction). Methods Twenty patients received both cardiac MRI and ECHO. Among them, nine patients received perfusion scans. The modalities and methods examined in this study were not the most advanced or updated protocols. Results We compared the results of cardiac MRI with those of ECHO and perfusion scans. We found significant correlations between the interpretations of left ventricular wall morphological change with dynamic images for hypokinesia, akinesia, and dyskinesia of the myocardium. We also found possible correlations between cardiac MRI and perfusion scans regarding their results to produce a “bull's eye target figure” to evaluate severe ischemia and infarctions. Conclusion We found that cardiac MRI provided a useful adjunct to ECHO on interpretations of left ventricular wall morphological change. The correlations between qualitative interpretations of cardiac MRI versus perfusion scan respective to ‘bull's eye target figures’, were found to be moderately matching. There was an unsatisfactory mismatching of correlations between quantitative by manual input and the drawing inaccuracy and an unavoidable error of the post-processing technique of cardiac MRI on ejection fraction (EF) and end systolic volume (ESV).

Background/Purpose Cardiovascular disease accounts for more than 50% of deaths among patients with end-stage renal disease, and numerous factors have been proposed that may contribute to this increased risk of death. Coronary artery calcification has been recognized as one of the important risk factors for cardiovascular disease in patients undergoing dialysis. The aim of this study was to compare the coronary artery calcification score (CACS) in peritoneal dialysis (PD) and hemodialysis (HD) patients, and to assess the effect of dialysis during a 12-month period. Methods Multidetector computed tomography was performed in 33 chronic dialysis patients (15 PD and 18 HD patients; mean age, 54 years) at Months 1, 6, and 12 during the study period. Blood samples were collected from each patient monthly to measure the serum levels of calcium and phosphorus. Results The CACSs were significantly increased at Month 12 versus Month 1 in both PD and HD patients (p Conclusions Our data suggest that the increase in CACS is not different between the PD and HD patients. Furthermore, the decrease in CACS between Months 7 and 12 suggests that there could be a factor other than the level of the calcium–phosphorus product that accounts for the variation in CACS in both groups.

Background The 64-multidetector computed tomography (64-MDCT) has developed into a mature clinical tool to detect coronary artery disease. This 64-MDCT system permits cross-sectional and longitudinal imaging of the coronary arteries with a high spatial and temporal resolution. However, small vessels, side branches and the distal portions of the main coronary arteries are not always optimally visualized. Purpose The aim of this study was to evaluate the effect of nitroglycerin (NTG) on lumen diameters and the number of visualized side branches of the coronary arteries on 64-MDCT. We also assessed whether NTG would affect the quality of the images of the coronary arteries obtained by 64-MDCT. Methods Sixty-seven patients were randomized and divided into two groups: Group C (31 patients, no sublingual NTG) and Group N (36 patients, sublingual NTG given before the scan). We measured the lumen diameter of the coronary artery and visibility of the side branches by using the 64-MDCT system and also evaluated the image quality by using the scores. Results The cardiac 64-MDCT images of these patients showed that the average diameters of the proximal segments in the right coronary artery, left main artery, left anterior descending coronary artery, and left circumflex coronary artery were 4.1 ± 0.7 mm, 3.9 ± 0.6 mm, 3.6 ± 0.7 mm, and 3.4 ± 0.6 mm, respectively, in Group N and 3.0 ± 0.5 mm, 3.1 ± 0.6 mm, 2.8 ± 0.5 mm, and 2.7 ± 0.5 mm, respectively in Group C. In addition, the scores for visibility and image quality for the side branches in Group N were significant higher than for those in Group C. Conclusion Our study indicates that CT coronary angiography using 64-MDCT with NTG administration produces images of diagnostically acceptable quality in all coronary segments. Thus, NTG might be recommended for routine 64-MDCT coronary angiography examinations.

Background/Purpose The incidence of breast cancer in Taiwan is increasing, and this form of cancer has already become the number one malignancy. Taiwanese women share similar characteristics of breast cancer with other developed Asian countries such as a younger age at diagnosis. In addition, a large proportion of Asian women have dense glandular breast tissue, which lowers the sensitivity of mammography for cancer detection. In this study, we compared possible differences in image interpretation of digital mammography and a dedicated breast magnetic resonance imaging system (using spiral RODEO). Methods From March 2008 to April 2009, we retrospectively collected data on 106 Taiwanese women who received both digital mammography and dedicated breast magnetic resonance imaging examinations in the same period. We divided these cases into non-dense and dense groups according to breast density, and compared the image interpretations based on the different modalities. Results There were statistically significant differences (p Conclusion Mammography may be useful for screening in non-dense breast tissue, but breast magnetic resonance imaging should be an additional screening tool in populations with dense breast tissue.

Background High-attenuation oral contrast agents in the form of iodine solutions or barium suspensions have been used traditionally and effectively for abdominal computed tomography (CT) examinations. Apart from the unpleasant taste, there are relatively few disadvantages that may affect interpretation, such as pseudotumor formation due to incomplete mixing of contrast material with the bowel contents and poor mural discrimination. Thus, low-attenuation oral contrast materials are needed. Purpose The aim of this study was to evaluate the efficiency of whole milk as a low-attenuation contrast agent compared with water-soluble contrast medium and water for abdomi-nopelvic CT. Methods A total of 152 patients were randomly assigned to receive whole milk (4%), water or water-soluble contrast medium (Optiral). All CT scans were performed using a 64-multidetector CT scanner with a 0.35-second rotation time. Two radiologists were responsible for reviewing the images to assess bowel wall enhancement and bowel dilation. Results There were no differences in average dilation scores among the three groups for duodenum and jejunum. The average dilation score in the milk group was higher than that in the water-soluble contrast medium group in the antrum, and there was no difference between water and milk. For the ileum, there were no differences in the average dilation scores in the milk and water-soluble contrast medium groups, and milk produced better dilation compared with water. Bowel enhancement in the water and milk groups was stronger than that in the water-soluble contrast medium group. The major side effects of milk were nausea and flatulence. Conclusion We concluded that abdominopelvic multidetector CT with whole milk provides better bowel dilation and wall visualization compared with high-attenuation contrast medium. Whole milk and water have potential as good oral contrast materials for bowel discrimination. However, whole milk should be considered as an alternative to water in cases of disease suspected in the pelvis.

Foreign body ingestion is a commonly seen medical emergency in children. Retropharyngeal abscess and mediastinitis are well-documented complications from foreign body ingestion, which reflects the importance of early diagnosis. The neck radiograph is the most significant radiographic examination performed in a child with a suspected pharyngeal lesion. We report a case where the initial malpositioned lateral view neck radiograph failed to detect a potentially serious esophageal foreign body. A second lateral view neck radiograph discovered a mass of foreign body in the upper esophagus, which was found to be a chicken bone during surgery. The case suggests that a properly positioned neck radiograph is the most important examination in the initial evaluation of a child with suspected foreign body ingestion.