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991.
Objective Diabetes mellitus is an independent risk factor for acute myocardial infarction. Thus, a surveillance study was conducted as part of studies to create a national database related to electrocardiogram (ECG)-gated myocardial perfusion single-photon emission computed tomography (SPECT) of ischemic heart disease. Methods Single-photon emission computed tomography was conducted in patients with type 2 diabetes mellitus and their prognoses will be followed for 3 years, stratified by patients’ clinical background and SPECT findings. Results A total of 513 patients from 50 institutions were enrolled in this study, 297 of whom were men (age 66.2 ± 0.4 years, mean ± SEM) and 261 women (age 67.8 ± 0.5 years). They have a history of retinopathy (25.3%), neuropathy (19.9%), cerebrovascular disorder, chronic obstructive pulmonary disease, and photocoagulation. Major risk factors for present disease were hypertension (82.3%) and hyperlipidemia (79.7%). In 244 patients (129 men and 115 women), body mass index (BMI) was 25 or more. Fifty-two of them (10.1%) underwent coronary angiography; of these, 26 (50.0%) had no coronary artery lesions with 75% or more stenosis, and only 1 (1.9%) had a left main trunk with 50% or more stenosis. An overwhelming majority of patients (94.3%) underwent SPECT imaging by a 1-day stress-followed-by-rest procedure. Stress procedure was exercise in most (70.8%) patients, followed by dipyridamole infusion in 14.6%, adenosine infusion in 6.6%, and adenosine triphosphate infusion in 5.7%. Endpoint of stress examination was most often fatigue in lower limbs (40.7%), followed by completion of pharmacological stress protocol (28.7%), and achievement of target heart rate (26.3%). The largest number of patients (198, 38.6%) received 99mTc-tetrofosmin at an initial dosage of 200–300 MBq (mean 331 ± 3 MBq) followed by a second dosage of 700–800 MBq (mean 748 ± 8 MBq). Among them, 491 (95.7%) received some kind of therapeutic drug: hypoglycemic drugs were used by the largest number (83.2%), followed by hypotensive (66.7%), hypolipidemic (40.7%), and antiplatelet drugs (27.7%), vasodilators (5.5%), and antioxidants and others (2.3%). Conclusions This study was designed to clarify the correlation between coronary artery disease and diabetes mellitus as its risk factor based on the clinical and imaging findings. Patient enrollment was closed on September 30, 2005, and follow-up is now under way.  相似文献   
992.
Primary renal synovial sarcoma is a rarely seen renal neoplasm. An experienced uropathologist is needed to make the pathological diagnosis. A patient, operated on with a prediagnosis of renal cell carcinoma, the pathology of which was reported as synovial sarcoma, is presented in this article. 18F-fluoro-deoxyglucose positron emission tomography and computed tomography were performed preoperatively and in the postoperative follow-up to detect the primary tumor and lymph node metastases.  相似文献   
993.
Tenosynovial giant cell tumor and pigmented villonodular synovitis   总被引:2,自引:0,他引:2  
  相似文献   
994.
Kim HJ  Jun BY  Kim WH  Cho YK  Lim MK  Suh CH 《Skeletal radiology》2002,31(11):637-642
OBJECTIVE:. The alar ligament plays a critical role in limiting the axial rotation of the head, the left alar ligament being stretched on rotation to the right and vice versa. The purposes of this study were to assess the usefulness of MR imaging in demonstrating the alar ligament and also to identify its morphologic changes during axial rotation of the head in asymptomatic young volunteers. DESIGN AND PATIENTS:. Twenty-two healthy volunteers participated in this study. All subjects underwent four series of contiguous fast spin echo density-weighted MR images with a 2 mm slice thickness including axial and coronal images with the head in neutral position, and coronal images with alternate head rotation to the right and left. The alar ligaments seen on each series of MR images were visually graded 0-2, and grade comparisons were performed between the four series of MR images. We also assessed the morphologic changes of the alar ligament on coronal images during axial rotation of the head. RESULTS:. Grade comparisons for the demonstration of the alar ligament revealed that each of three series of coronal images was statistically significantly better in grade than axial images. During axial rotation of the head, MR images showed rather constant morphologic changes of the alar ligament: elevation and wrapping of the contralateral alar ligament around the dens, associated with slightly upward movement of C1-C2 on that side. This wrap-around effect of the contralateral alar ligament in relation to the dens sometimes caused the apparent shortening of the alar ligament on that side. CONCLUSION:. Reliable assessment of the anatomy and function of the alar ligament can be achieved with MR imaging, preferably in coronal planes. MR imaging with the aid of a functional study may be a valuable imaging modality in the evaluation of alar ligament failure.  相似文献   
995.
996.
"Seeing inside the body": MR imaging of gene expression   总被引:5,自引:0,他引:5  
The goal of this review is to describe the developments and recent advances that are enabling applications of magnetic resonance (MR) imaging for non-invasive imaging of gene expression. Guiding application of this technology has been the need to test, in vivo and in real time, hypotheses developed in multiple scientific fields. Advances made in the human genome project and our increasing understanding of the molecular basis of normal and disease physiology have defined questions that will only be answered when specific molecular imaging modalities are developed. In this review we will briefly summarize the salient features of MR imaging to provide the backdrop for a more detailed discussion of specific applications of MR imaging of gene expression. We will conclude with the insights gained from genomic approaches and how they might be exploited for MR imaging of gene expression in the future.  相似文献   
997.
New frontiers in CT imaging of airway disease   总被引:7,自引:0,他引:7  
Combining helical volumetric CT acquisition and thin-slice thickness during breath hold provides an accurate assessment of both focal and diffuse airway diseases. With multiple detector rows, compared with single-slice helical CT, multislice CT can cover a greater volume, during a simple breath hold, and with better longitudinal and in-plane spatial resolution and improved temporal resolution. The result in data set allows the generation of superior multiplanar and 3D images of the airways, including those obtained from techniques developed specifically for airway imaging, such as virtual bronchography and virtual bronchoscopy. Complementary CT evaluation at suspended or continuous full expiration is mandatory to detect air trapping that is a key finding for depicting an obstruction on the small airways. Indications for CT evaluation of the airways include: (a) detection of endobronchial lesions in patients with an unexplained hemoptysis; (b) evaluation of extent of tracheobronchial stenosis for planning treatment and follow-up; (c) detection of congenital airway anomalies revealed by hemoptysis or recurrent infection; (d) detection of postinfectious or postoperative airway fistula or dehiscence; and (e) diagnosis and assessment of extent of bronchiectasis and small airway disease. Improvement in image analysis technique and the use of spirometrically control of lung volume acquisition have made possible accurate and reproducible quantitative assessment of airway wall and lumen areas and lung density. This contributes to better insights in physiopathology of obstructive lung disease, particularly in chronic obstructive pulmonary disease and asthma.  相似文献   
998.
Breast cancer imaging with MRI   总被引:25,自引:0,他引:25  
Breast MRI is an emerging technology that may revolutionize our management of women with known or suspected breast cancer. MRI examinations should be interpreted with an awareness of the pitfalls and artifacts that can affect on image evaluation. Development of an MRI lexicon will assist by providing standardized terminology that may improve our understanding of the positive predictive value of different MRI features. To date, breast MRI has proven most useful in patients with proven breast cancer to assess for multifocal/multicentric disease, chest wall involvement, chemotherapy response, or tumor recurrence or to identify the primary site in patients with occult breast cancer. Further work is necessary to assess the utility of breast MRI in other settings, such as screening of women at high risk for breast cancer.  相似文献   
999.
Most intra-abdominal and other types of fluid collections are now successfully drained percutaneously under image guidance. The utility of percutaneous drainage of tuberculous abscesses, especially those associated with osseous changes, is, however, less well established. Six patients with tuberculous iliopsoas abscesses were successfully managed by percutaneous drainage combined with antituberculous therapy. The abscesses were bilateral in one patient and unilateral in the other five. Drainage was by needle aspiration under ultrasound (US) guidance in one patient, and by catheter under CT guidance in the other patients. Three patients had associated osseous changes. There were no procedural complications. Tuberculous iliopsoas abscess can be successfully treated by percutaneous drainage and appropriate antituberculous therapy.  相似文献   
1000.
Introduction Idiopathic granulomatous mastitis (IGM) is a rare benign inflammatory breast disease that presents with variable local manifestations. We describe here the different management protocols based on the clinical presentation of these patients. Methods A retrospective review of 20 histopathologic confirmed cases of IGM seen over a period of 10 years was performed. Results The median age was 34 years (age range: 21–45 years). All were married, parous with history of breast feeding. Ill-defined mass mimicking carcinoma was the commonest presentation (70%); however, with the presence of signs of inflammation like pain (55%), redness (40%), and peau d’orange (40%), an inflammatory process appeared more likely. Axillary lymph node enlargement was infrequently seen (40%). Radiologic findings (mammography and ultrasound) were nonspecific. Histopathology showed the characteristic lobular distribution of granulomatous inflammation in all cases. Surgically, 7 patients had abscess drainage with open biopsy, and 7 patients had lumpectomy. Six patients with diffuse breast involvement were diagnosed by core needle biopsy only. Microbial cultures showed no growth. Antibiotics were given empirically when signs of inflammation where present. Two patients needed further abscess drainage followed by persistent sinus excision 3–6 weeks later. The median follow-up was 24 months (range: 15–42 months). Seventeen patients (85%) were recurrence-free, and 3 patients (15%) were lost to follow-up. Conclusions Management of IGM cases needs to be tailored according to the clinical presentation. Precise radiologic and pathologic data interpretation by a multidisciplinary breast team will facilitate diagnosis and minimize unnecessary intervention.  相似文献   
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