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1.
The aim of this study was to evaluate the clinical relevance of coronary artery calcifications detected by spiral CT, congruence with fluoroscopy (FS) and coronary angiography, and comparison with studies reporting on application of double-helical CT and ultrafast CT. Forty patients underwent spiral CT (2-mm slice thickness, table feed 3 mm/s), coronary angiography, and FS (performed in the usual manner). Stenosis and calcifications were evaluated semiquantitatively. Nineteen patients suffering from a stenosis >/= 75 % were verified at coronary angiography. All had coronary artery calcification on spiral CT. Fluoroscopy did not detect 8 of 19 patients with a stenosis >/= 75 % (1 vessel: n = 1; 2 vessels: n = 3; 3 vessels: n = 4). In spiral CT sensitivity was 100 % and specificity was 33 % (FS: 58 and 48 %). Positive predictive value was 83 % for spiral CT (FS: 50 %), and negative predictive value was 100 % (FS: 56 %). A significant linear increase in the calcification score was found for increasing maximal stenosis (p < 0.005). Spiral CT is more sensitive than FS in the recognition of hemodynamic relevant stenoses using the detection of coronary artery calcifications. Statistical parameters are comparable to ultrafast-CT. Spiral CT is a suitable non-invasive diagnostic technique in coronary heart disease. Coronary calcifications found incidentally in symptomatic patients at chest CT should be reported to the referring physician for further cardiological workup.  相似文献   

2.
PURPOSE: Coronary calcium is a powerful indicator of arteriosclerosis and can be detected very precisely with electron beam tomography. The method can be applied in patients with known coronary artery disease or in asymptomatic patients at risk of arteriosclerotic disease. METHODS: The standard protocol of EBT consists of 30 to 40 slices of 3-mm thickness with a scan time of 100 ms, no overlap. No contrast medium is needed. The total scan can be performed within one breathhold. The calcium score is calculated as described by Agatston. Radiation exposure amounts to 0.8 mSv per total screen. We used spiral CT with and without ECG trigger as an alternative. RESULTS: At the University of Munich we performed an EBT scan of the heart in 1100 patients within the last year. In 567 patients coronary angiography was performed also (+/- 3 days). Confirming previous reports in the literature, we found a correlation of the calcium score with the age and gender of the patients. Severe coronary artery disease (stenoses > or = 75%) was associated with significantly more calcium than less severe CAD. The calcium score did not discriminate between one-, two- and three-vessel disease. The site of calcification does not correlate with the localization of stenoses. Thirty-three percent of the patients with significant coronary artery disease showed a normal age-adjusted calcium score; a total of 8.1% of patients with severe stenoses did not reveal any coronary calcification (score = 0). With asymptomatic patients there are only a few studies available. Soft plaques cannot be detected with EBT, but in most patients soft plaques occur together with hard plaques. Our results show that spiral CT of the newest generation may also be used for calcium screening. There was an excellent correlation of the calcium scores of EBT and spiral CT at all levels of calcification. DISCUSSION: Coronary calcium is a sensitive marker of coronary artery disease. In the clinical setting EBT is indicated in patients with known coronary artery disease (to evaluate prognosis), in patients who are unable to perform a stress test, and in patients with atypical chest pain. However, lack of calcification may be associated with severe stenoses in a minority of patients. The clinical value in asymptomatic patients needs to be defined: randomized studies are necessary. We see a possible indication in patients with known risk factors, in whom primary preventive strategies could be performed more selectively and cost-effectively.  相似文献   

3.
PURPOSE: To evaluate a discrepancy between the location of renal artery stenoses on intraarterial digital subtraction angiographic (DSA) images and that on spiral computed tomographic (CT) angiograms. MATERIALS AND METHODS: The spiral CT angiograms and intraarterial DSA images of 40 consecutive patients with atherosclerotic renal artery stenoses were examined retrospectively. Stenoses were classified as truncal or ostial. The atherosclerotic changes in the abdominal aorta were graded. RESULTS: Fifty-eight stenoses were demonstrated. In 48 ostial stenoses, there was no discrepancy in the location of the stenoses on spiral CT angiograms and DSA images. In 10 patients, spiral CT angiography showed an ostial lesion, whereas DSA demonstrated an apparent truncal lesion. Most of these stenoses ("pseudotruncal" ostial stenoses) were in patients with severe aortic atherosclerotic disease. CONCLUSION: A renal artery stenosis at or within 10 mm of an atherosclerotic aorta at DSA may be diagnosed as an ostial stenosis.  相似文献   

4.
RATIONALE AND OBJECTIVES: Imaging techniques that distinguish atherosclerotic plaque components may be useful in identifying the nature of the atherosclerotic lesion and determining the best method of treatment for obstructive vascular mining the best method of treatment for obstructive vascular disease. This study compares fast spin-echo (FSE) magnetic resonance (MR) and spiral computed tomography (CT) images of excised human atherosclerotic aortas to determine which imaging technique provides the best contrast between plaque components ex vivo. METHODS: Aortas were imaged using four FSE sequences in MR with and without frequency-selective fat saturation, and using spiral CT without contrast. The average signal intensity of a region of calcification, thrombosis, fatty plaque, and normal vessel wall was measured on all images and compared. RESULTS: The use of fat saturation pulses in MR did not significantly alter the signal from atherosclerotic plaque for the sequences used. Proton density-weighted FSE sequences that collected early echoes were better than other FSE sequences and CT at differentiating calcification from all soft tissues. T2-weighted FSE sequences that collected later echoes were best at soft-tissue discrimination. CONCLUSIONS: The FSE techniques used were superior to nonenhanced spiral CT in discriminating plaque components ex vivo, including calcification.  相似文献   

5.
Coronary artery disease continues to be the primary cause of mortality in the United States. Recent studies have significantly advanced the ability to improve outcomes in this disorder by demonstrating that intensive risk factor modification programs with diet, lipid-lowering drugs, exercise, and psychosocial interventions can reverse atherosclerosis and reduce events by 40% to 60%. Of all the interventional arms, psychosocial interventions have been the least studied despite research demonstrating that depression and social isolation are potent risk factors for events in patients with coronary artery disease. The few studies that have examined psychosocial interventions in patients with coronary artery disease have demonstrated a reduction in mortality and recurrent events, suggesting that this treatment strategy may be beneficial. Use of volunteer, patient-driven support groups may provide a cost-effective way to improve social support and enhance altruism in patients with coronary artery disease. Although the psychophysiology of altruism is not well defined, it is possible that altruistic activities might have positive health benefits in patients with coronary artery disease. Studies are needed to explore the roles of low-cost, patient-driven support programs in improving psychosocial functioning and outcomes in patients with coronary artery disease.  相似文献   

6.
PURPOSE: To determine whether axial spiral computed tomography (CT) allows detection of the replaced hepatic artery as part of preoperative planning for pancreatic tumor resection. MATERIALS AND METHODS: Axial spiral CT scans (8-mm section thickness, 4-mm overlapping reconstructions) were obtained in 50 patients with periampullary tumor and were examined by three radiologists. Readers' interpretations were compared with angiographic results. RESULTS: Eight patients had an aberrant hepatic artery. Two of the three readers detected or suspected all of these abnormalities (100% sensitivity), and one reader identified seven of eight aberrant arteries (88% sensitivity). However, readers requested angiographic confirmation in 14 of 24 tests. Sensitivity, specificity, and accuracy were 96%, 87%, and 88%, respectively, for all readers. CONCLUSION: Axial spiral CT may simplify preoperative evaluation of periampullary tumors. However, angiographic support was necessary in most cases in this study. Improvements in CT techniques may eventually allow spiral CT to replace angiography in the examination of these patients.  相似文献   

7.
PURPOSE: To compare spiral computed tomography (CT) and electron-beam CT (EBT) for 3D and virtual CT-bronchoscopy. MATERIALS AND METHODS: 17 patients with various disorders of the tracheobronchial system were examined using fiberoptic bronchoscopy, spiral CT and EBT. 3D images were reconstructed from CT data sets using automated segmentation based on volume-growing methods. Surface-rendered, volume-rendered, and hybrid reconstructions were visualized in real time using a data helmet. RESULTS: All data sets could be processed to high-quality three-dimensional (3D) and virtual reconstructions. The reduction of motion artifacts due to shorter scan times made EBT data sets better suited for automated segmentation and less susceptible to motion artifacts. 3D and virtual reconstructions did not increase the diagnostic sensitivity of CT compared to axial reconstructions alone. CONCLUSIONS: Shorter scan times of CT imaging yield higher-quality 3D and virtual reconstructions. Modern reconstruction techniques are valuable visualization tools for select indications and are the prerequisite for future developments in computer-aided medicine.  相似文献   

8.
Low-tension glaucoma (LTG) is manifested by glaucomatous optic nerve damage and visual field loss despite normal intraocular pressure (IOP). We describe 62 patients with classical signs of LTG. Computed tomography (CT) was performed in all patients. In 56 of the patients (90.3%), pathology of the intracavernous carotid arteries adjacent to the intracranial opening of the optic canal could be demonstrated. In 28 patients (45.2%) a clear asymmetry of the optic nerve cupping was found and could be correlated with the severity of the carotid artery pathology. A control group of 24 age-matched patients included five (20.8%) with intracavernous carotid artery calcification and only one (4.2%) with intracavernous ectasia. We suggest that calcification, dilatation and ectasia of the carotid artery into the optic canal may play an important role in the pathogenesis of many cases of LTG. The close proximity of the carotid artery to the optic nerve at this location may result in compressive neuropathy with subsequent glaucomatous damage of the optic nerve head.  相似文献   

9.
OBJECTIVES: This report used intravascular ultrasound and quantitative coronary angiography to explore the relation between lesion-associated calcium and risk factors, clinical presentation and angiographic severity of coronary artery stenoses. BACKGROUND: Coronary artery calcium is a marker for significant coronary atherosclerosis. Noninvasive procedures are being proposed as screening tests for coronary artery disease. Intravascular ultrasound identification of tissue calcium has been validated in vitro. METHODS: Independent chart review, preintervention intravascular ultrasound imaging and coronary angiography were used to study primary native vessel lesions in 1,442 patients. Target lesions and reference segments were evaluated according to previously published quantitative and qualitative methods. Results are presented as mean value +/- SD. RESULTS: Overall, 1,043 lesions contained target lesion calcium (72%); the arc of target lesion calcium was 110 +/- 109 degrees. Lesions with an ultrasound plaque burden > 0.75 or an angiographic diameter stenosis > 0.25 had a prevalence of calcium of at least 65%, with a mean arc > 100 degrees. Intermediate lesions had as much target lesion calcium as did angiographically severe lesions. Using multivariate linear regression analysis, patient age, stable (vs. unstable) angina and the intravascular ultrasound lesion site and reference segment plaque burden (but not the angiographic diameter stenosis) were the independent predictors of the arc of target lesion calcium (all p < 0.0001). CONCLUSIONS: Intravascular ultrasound analysis shows that coronary calcification correlates with plaque burden but not with degree of lumen compromise. Thus, the noninvasive detection of coronary calcium is predictive of future cardiac events, presumably because coronary calcification is a marker for overall atherosclerotic plaque burden. Coronary calcium increases with increasing patient age and is less common in unstable lesion subsets.  相似文献   

10.
During a five year period, idiopathic hypertrophic subaortic stenosis was diagnosed in nine patients 70 to 79 years of age and in 26 patients 20 to 66 years of age who were referred to the cardiology division of the Long Island Jewish-Hillside Medical Center because of symptomatic heart disease. Only one of the older patients, compared with 19 of the younger ones, was referred with the correct diagnosis. Coronary artery disease with papillary muscle dysfunction was incorrectly diagnosed in four of the older patients. Cardiac catheterization confirmed the diagnosis of idiopathic hypertrophic subaortic stenosis in all of the 26 younger patients and in five of the nine older ones; diagnosis was based on typical echocardiographic features in the other four patients. Symptoms, physical findings, and electrocardiographic observations were similar in both groups. Aortic valve calcification was found in one younger patient and three older ones. The ratio of women to men was higher in the older group (7:2) than in the younger group (12:14). Coronary artery disease was more frequent in the older patients (three of five, compared with six of 26). Our experience indicates that idiopathic hypertrophic subaortic stenosis is not rare during the eighth decade. The diagnosis should be considered in any patient with an unexplained appropriate heart murmur, and definitive studies, such as echocardiography, should be done. As with any condition, proper management depends on accurate diagnosis.  相似文献   

11.
OBJECTIVE: To determine the association between the use of hormone replacement therapy (HRT) and coronary calcium, in postmenopausal women who had no history of coronary artery disease by double helical computed tomography (CT). METHODS: We used CT to compare the prevalence and extent of coronary calcium in 41 postmenopausal women who were on HRT from the first year of menopause and 37 age-matched controls who had never used HRT. RESULTS: Both groups had a similar rate of smoking, hypertension, a positive family history, and hypercholesterolemia. Coronary calcification was observed in 28.2% of the 78 women studied. The prevalence of coronary calcium was significantly lower among HRT users: six of the 47 (14.6%), compared with 16 of the 37 nonusers (43.2%) (P < .01). The recorded risk factors had no effect on the prevalence of coronary calcium. Stepwise logistic regression analysis, including age, coronary risk factors, and HRT use as independent variables, yielded HRT as the only variable determining the presence of coronary calcium (odds ratio = 0.2; 95% confidence interval 0.06, 0.63; P = .006). CONCLUSION: The lower incidence of coronary calcium in the HRT users suggests that HRT is associated with decreased prevalence of the coronary calcification.  相似文献   

12.
Subsecond computed tomography (CT) scanning offers potential for improved heart imaging. We therefore developed and validated dedicated reconstruction algorithms for imaging the heart with subsecond spiral CT utilizing electrocardiogram (ECG) information. We modified spiral CT z-interpolation algorithms on a subsecond spiral CT scanner. Two new classes of algorithms were investigated: (a) 180 degrees CI (cardio interpolation), a piecewise linear interpolation between adjacent spiral data segments belonging to the same heart phase where segments are selected by correlation with the simultaneously recorded ECG signal and (b) 180 degrees CD (cardio delta), a partial scan reconstruction of 180 degrees + delta with delta < fan angle, resulting in reduced effective scan times of less than 0.5 s. Computer simulations as well as processing of clinical data collected with 0.75 s scan time were carried out to evaluate these new approaches. Both 180 degrees CI and 180 degrees CD provided significant improvements in image quality. Motion artifacts in the reconstructed images were largely reduced as compared to standard spiral reconstructions; in particular, coronary calcifications were delineated more sharply and multiplanar reformations showed improved contiguity. However, new artifacts in the image plane are introduced, mostly due to the combination of different data segments. ECG-oriented image reconstructions improve the quality of heart imaging with spiral CT significantly. Image quality and the display of coronary calcification appear adequate to assess coronary calcium measurements with conventional subsecond spiral CT.  相似文献   

13.
RATIONALE AND OBJECTIVES: Coronary artery stents reduce the rate of restenosis in patients who have undergone balloon angioplasty; therefore, the implantation of coronary stents represents an important method in the treatment of coronary stenoses. The authors' purpose was to investigate the usefulness of electron-beam computed tomography (CT) as a noninvasive means of assessing the patency of coronary artery stents in patients who had undergone balloon angioplasty and stent placement. MATERIALS AND METHODS: Electron-beam CT was used to assess stent patency in 177 patients with 285 stents. Contrast material-enhanced multisection flow studies were performed, and the images were evaluated by three investigators and compared with the findings of coronary angiography. RESULTS: Cine loop evaluations and time-attenuation curve analysis led to the correct diagnosis in 167 (94.3%) patients, as confirmed with coronary angiography. Stenoses had occurred in 18 of the 194 vessels with stents, and 14 of these were detected with electron-beam CT. CONCLUSION: Electron-beam CT appears to be a valuable imaging modality in the noninvasive assessment of stent patency in coronary arteries.  相似文献   

14.
PURPOSE: To determine if the lower milliampere second setting and shorter acquisition time of subsecond spiral computed tomography (CT) affects the image quality of thoracic CT scans. MATERIALS AND METHODS: In 92 consecutive outpatients referred for thoracic CT, spiral CT (120 kV, 292 mA) was performed with 1-second (n = 45) or 0.75-second (n = 47) scanning time. An equal percentage of patients (70%) in each group received intravenous contrast medium. At six mediastinal and six lung zones, degradation due to motion and noise, respectively, were graded independently on a four-point scale by three blinded radiologists. Statistically significant differences were determine with a two-tailed test. RESULTS: Mediastinal image quality was significantly better on 0.75-second scans than on 1-seconds scans (P < .001). Regions with the greatest improvement in image quality were around the aortic root, cardiac ventricles, and aortic arch. Lung image quality was also better on 0.75-second scans than on 1-second scans (P = .04). On 0.75- and 1-second scans, respectively, motion-related artifacts were found to degrade image quality 6.2 and 8.7 times more than noise-related artifacts in the mediastinum and 2.6 and 3.9 times more in the lungs. CONCLUSION: Subsecond spiral CT is associated with improved clarity and diminished motion artifacts on mediastinal and pulmonary images when compared with 1-second spiral CT.  相似文献   

15.
OBJECTIVE: The purpose of this prospective study was to compare CT angiography with conventional catheter angiography for imaging the bifurcation of the common carotid artery in patients with signs and symptoms of atherosclerotic disease. SUBJECTS AND METHODS: Ten symptomatic patients (20 bifurcations of the common carotid artery) underwent contrast-enhanced spiral CT of the neck. The images were preprocessed and postprocessed by using a commercially available volume-rendering technique and a maximum-intensity-projection algorithm. All patients subsequently underwent conventional catheter angiography. RESULTS: CT angiographic findings matched those on conventional angiograms in only 50% of cases. Two nearly occluded internal carotid arteries were missed with CT angiography. Four internal carotid arteries were interpreted as occluded on the basis of CT angiograms but were shown as patent on catheter angiograms. Of five severe stenoses shown by CT angiography, only two were confirmed by conventional angiography. CONCLUSION: The results indicate that CT angiography as used in this study cannot replace catheter angiography. With CT angiography, both overestimation and underestimation of stenoses occur.  相似文献   

16.
PURPOSE: To compare prospectively the accuracy of spiral computed tomography (CT) with that of ventilation-perfusion scintigraphy for diagnosing pulmonary embolism. MATERIALS AND METHODS: Within 48 hours of presentation, 142 patients suspected of having pulmonary embolism underwent spiral CT, scintigraphy, and (when indicated) pulmonary angiography. Pulmonary angiography was attempted if interpretations of spiral CT scans and of scintigrams were discordant or indeterminate and intermediate-probability, respectively. RESULTS: In the 139 patients who completed the study, interpretations of spiral CT scans and of scintigrams were concordant in 103 patients (29 with embolism, 74 without). In 20 patients, intermediate-probability scintigrams were interpreted (six with embolism at angiography, 14 without); diagnosis with spiral CT was correct in 16. Interpretations of spiral CT scans and those of scintigrams were discordant in 12 cases; diagnosis with spiral CT was correct in 11 cases and that with scintigraphy was correct in one. Spiral CT and scintigraphic scans of four patients with embolism did not show embolism. Sensitivities, specificities, and kappa values with spiral CT and scintigraphy were 87%, 95%, and 0.85 and 65%, 94%, and 0.61, respectively. CONCLUSION: In cases of pulmonary embolism, sensitivity of spiral CT is greater than that of scintigraphy. Interobserver agreement is better with spiral CT.  相似文献   

17.
Electron-beam or ultrafast computerized tomographic (CT) scanning provides a convenient and sensitive means of detecting coronary calcification, which is an early index of atherosclerosis. The procedure has strong negative predictive power for the presence of coronary artery disease, but a limited ability to predict disease severity. However, preliminary indications are that it is as good or better than conventional risk factors in this respect. Although further validation is needed before electron-beam CT can be regarded as an established method of detecting presymptomatic coronary atherosclerosis, the procedure has potential in this context.  相似文献   

18.
A relationship of coronary arterial spasm to variant angina pectoris, subendocardial ischemia, major ventricular arrhythmias and myocardial infarction has been demonstrated. In 29 patients, spasm was angiographically observed in normal-appearing coronary arteries (7 patients) as well as superimposed on various degrees of coronary atherosclerotic obstruction (22 patients). All patients experienced an atypical anginal syndrome;16 patients also experienced typical exertional angina. Coronary spasm appeared to be a major contributory factor in eight occurrences of myocardial infarction and in 11 incidents of ventricular tachycardia, ventricular fibrillation and heart block. Coronary spasm in the 29 cases was distributed in the following fashion: left main trunk, 6 cases; right main trunk, 12 cases; proximal left anterior descending artery, 13 cases; proximal circumflex artery, 1 case; distal left anterior descending artery, 1 case; and distal circumflex artery, 2 cases. In 5 cases coronary spasm was noted at multiple sites.  相似文献   

19.
Myocardial stunning has been poorly described in patients with cerebrovascular accidents. We present a patient in whom severe anteroapical wall motion abnormalities and extensive anterior ST-segment elevation developed after subarachnoid hemorrhage. Total recovery ensued within 2 days. Coronary vasospasm induced by stroke-related sympathetic surge might be the determinant factor of this cardiac event.  相似文献   

20.
This article compares intergroup and intragroup clinical and morphologic findings in patients with ischemic cardiomyopathy (IC), idiopathic dilated cardiomyopathy (IDC), and dilated hypertrophic cardiomyopathy (HC) undergoing cardiac transplantation (CT). Few previous publications have described findings in native hearts explanted at the time of CT. The explanted heart in 92 patients having CT was examined in uniform manner with particular attention to the sizes of the ventricular cavities and the presence of and extent of ventricular scarring. Of the 92 hearts examined, 47 had IC, 35 had IDC, and 10 had dilated HC. Although considerable degrees of intragroup variation occurred, the mean degree of left ventricular dilatation was similar among the patients with IC, IDC, and dilated HC. All patients with IC had left ventricular free wall scarring more extensive than that involving the ventricular septum, but the intragroup variation in the amounts of scarring was considerable. Nine of the 10 patients with dilated HC also had ventricular wall scarring, but it was more extensive in the ventricular septum than in the left ventricular free wall and involvement of the right ventricular wall also was present. Eight (23%) of the 35 IDC patients also had grossly visible ventricular scars but they were small and only 1 of the 8 had coronary narrowing and that was not in the distribution of the scarring. Narrowing of 1 or more epicardial coronary arteries >75% in cross-sectional area by plaque was present in all 47 IC patients, in 8 of the 35 IDC patients (7 had no ventricular scars), and in none of the 10 dilated HC patients. Coronary angiography was the major clinical tool allowing separation of the IC, IDC, and HC patients. Coronary angiography did not detect narrowing in any of the 8 patients with IDC who were found to have coronary narrowing on anatomic study. Thus, among patients with IC, IDC, and dilated HC having CT, distinctive anatomic features allow separation of patients with IC, IDC, and dilated HC, but within each group considerable variation in left ventricular cavity size and extent of ventricular scarring occurs.  相似文献   

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