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Calcification overlying the left side of the heart on a chest radiograph may involve either the pericardium or, alternatively, the myocardium in association with a left ventricular aneurysm. Distinction between these two conditions can be of great clinical significance. To identify distinguishing features, we reviewed the radiographs and medical records of 29 patients: 14 had proven calcific pericarditis and 15 had proven calcified left ventricular aneurysm. Pericardial calcification was found primarily over the right-sided cardiac chambers (14 of 14 patients) and in the atrioventricular grooves (11 of 14), infrequently over the base of the left ventricle (five of 14), and rarely over the apex of the left ventricle (two of 14). When the left ventricle was involved, there was always more extensive calcification elsewhere in the pericardium. Myocardial calcification occurred predominantly in the apex of the left ventricle (13 of 15 patients), although it was rarely confined to the posterior wall of the left ventricle (two of 15). By noting characteristic sites of calcium deposition, pericardial calcification can be effectively distinguished from myocardial calcification. Isolated calcification in the region of the left ventricular apex, therefore, strongly suggests left ventricular aneurysm.  相似文献   

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R C Sanders  D S Hartman 《Radiology》1984,151(3):621-625
Distinction between multicystic kidney and hydronephrosis, the two most common causes of neonatal abdominal masses, is important because of differences in management; however, these two entities may have a similar ultrasonographic appearance. Sonograms of 22 cases of multicystic kidney and hydronephrosis were retrospectively reviewed without knowledge of the pathologic findings to determine if the sonographic patterns were sufficiently distinct to be usable in clinical diagnosis. Nine of the 22 cases were correctly diagnosed with ultrasound as multicystic kidney, 6 cases were correctly diagnosed as hydronephrosis, and 7 cases of pathologically proved multicystic kidney were incorrectly diagnosed as hydronephrosis. Four of these incorrect diagnoses occurred in cases of the hydronephrotic type of multicystic kidney. An additional 9 cases were reviewed with knowledge of the pathologic results. It is concluded that sonography is accurate at differentiating classic multicystic kidney disease from moderate hydronephrosis; however, there is often considerable difficulty in distinguishing severe hydronephrosis from the hydronephrotic form of multicystic kidney disease.  相似文献   

4.
In contrast to skin wounds the characteristic forensic features of lesions of ligaments and tendons have rarely been investigated. However, in a suspected homicide the question became crucial whether an isolated discontinuity of the posterior atlanto-occipital membrane was caused by a rupture mechanism or by a cut. In order to re-evaluate the associated criteria experimental lesions were made in ligaments and tendons and examined histologically. From these experiments the following criteria could be established:Lacerations exhibit complete destruction of the tissue texture with microruptures and splitting of fibres in the adjacent region. Such wound edges have an irregular structure and fibres near the rupture site exhibit variable thicknesses due to traction.Incisions exhibit smooth wound edges with no disturbance of the tissue texture. The thickness of fibres near the rupture site is regular. These results were obtained by light microscopical examination and confirmed using electron microscopy. Under controlled experimental conditions the forces necessary to rupture tendons with a diameter of 1 mm varied between 50–70 Newton (N). In the suspected homicide, the lesion of the posterior atlanto-occipital membrane was examined visually and histologically and was compared with the experimentally established criteria. Based on these criteria the lesion could be identified as an incision which had probably been caused accidentally while severing the medulla during the first autopsy and was therefore not connected with the cause of death.  相似文献   

5.
At the beginning of the new century Humankind is facing a new Era. It has to face the effects of a dramatic and accelerated population growth. Human population size increased from one billion in 1835, to six billion by the end of this century. This unprecedented increase in number, affecting specific geographical areas, has augmented the deterioration of the natural environment caused by the misuse of natural resources and the depletion of fertile soils due to climatic changes and pollution. The quality of life is now diminished by the "greenhouse effect" which is the direct result of industrialisation. Ecological integrity is a concept that has to be advanced in order to facilitate the protection of biological and ecological resources against the threat of human survival. Global Bioethics as a discipline of interaction of health professionals with the present endangered environment, the limited global resources and the new biotechnologies is needed in any Biomedical School.  相似文献   

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Although sonography is useful in the evaluation of renal transplants, there are no objective sonographic findings for reliably differentiating acute rejection from cyclosporine nephrotoxicity. This study was undertaken to determine the role of pulsed Doppler flow analysis (duplex sonography) in making this distinction. Duplex Doppler sonography was performed in 106 patients with normally functioning transplanted kidneys and in 34 patients with renal transplant dysfunction who underwent percutaneous biopsy. Renal vascular impedance was estimated in the segmental, interlobar, and arcuate arteries by calculating the ratio of end-diastolic minimum velocity to systolic peak velocity (diastolic/systolic ratio). In the healthy control subject, the diastolic/systolic velocity ratios varied in the different arterial segments, ranging from a mean of 0.23 in the segmental arteries to a mean of 0.32 in the arcuate arteries. Seventeen patients experienced acute rejection: eight of the nine with acute vascular rejection had abnormal Doppler ratios; eight patients with acute cellular rejection had normal ratios. Nine patients with cyclosporine nephrotoxicity all had normal duplex scans. Seven patients with chronic rejection had normal ratios. One patient with hemolytic-uremic syndrome had an abnormal flow pattern. These findings indicate that duplex sonography may be useful in differentiating acute vascular rejection from cyclosporine nephrotoxicity in the transplanted kidney.  相似文献   

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The radiologic distinction of cardiogenic and noncardiogenic edema   总被引:4,自引:0,他引:4  
Improvement in the ability to determine the specific cause of any given case of pulmonary edema would lead to more rapid and definitive treatment. "Wedge" pressures and measurements of cardiac output derived from Swan-Ganz catheterization assist in making this determination, but the procedure is invasive, expensive, associated with complications, and not infrequently inaccurate. A plain chest film is, however, almost invariably available in all patients with pulmonary edema, and as shown in this study, the cause of the edema can be determined with a high degree of accuracy by careful attention to certain radiographic features. An independent two-observer study was performed on 216 chest radiographs of 61 patients with cardiac disease, 30 with renal failure or overhydration, and 28 with capillary permeability edema. Three principal and seven ancillary features have been identified, all of which are statistically significant and permit the cause of the edema to be determined correctly in a high percentage of cases. The three principal features are distribution of pulmonary flow, distribution of pulmonary edema, and the width of the vascular pedicle. The ancillary features are pulmonary blood volume, peribronchial cuffing, septal lines, pleural effusions, air bronchograms, lung volume, and cardiac size. Differing constellations of these features occur, each of which is characteristic of a specific type of edema. Overall accuracy of diagnosis in this study ranged from 86% to 89%. The highest accuracy was obtained in distinguishing capillary permeability edema from all other varieties (91%), and the lowest in distinguishing chronic cardiac failure from renal failure (81%).  相似文献   

8.
Aortic calcification, either mural or thrombus, is a common finding in patients with abdominal aortic aneurysms. Differentiating between the two sites of calcification is necessary in order to avoid confusing simple thrombus calcification with displaced calcified intima in aortic dissection. The CT scans of 145 cases of abdominal aortic aneurysm and seven cases of abdominal aortic aneurysm with dissection were analyzed with respect to the location of the calcification: mural only or mural and thrombus. Mural calcification was seen in all 152 patients with aneurysms whereas thrombus calcification was identified in only 33 (24%) of the 136 patients with thrombus. Displaced intimal calcification caused by aortic dissection can either appear similar to or, at times, be indistinguishable from thrombus calcification. Thrombus calcification was present in four (57%) of the seven patients with abdominal aortic aneurysms and dissection. To avoid the possibility of a false-positive diagnosis of aortic dissection in patients with abdominal aortic aneurysm, other signs of aortic dissection should be sought such as separation of the true and false lumina by an intimal flap.  相似文献   

9.
OBJECTIVE. The purpose of this study was to determine the diagnostic value of the sonographic halo sign (defined as any hypoechoic rim in the periphery of a lesion) in distinguishing between benign and malignant isoechoic and hyperechoic liver lesions on sonography. MATERIALS AND METHODS. Sonograms of the liver in 50 patients with proved benign liver tumors and in 50 patients with proved malignant liver tumors (seven primary liver neoplasms, 43 metastases) selected during a 13-month period were retrospectively analyzed by four radiologists who had no knowledge of the patients' clinical findings or the final diagnoses. Only a single sonogram was studied in each case. The presence or absence of a hypoechoic halo on the sonogram was the only criterion for distinguishing malignant from benign hepatic lesions. RESULTS. For 95 of 100 hepatic lesions, the four radiologists were almost (three vs one) or completely (four vs zero) in agreement about the presence or absence of a hypoechoic halo. In the five cases where there were conflicting decisions (two vs two), a final decision (four vs zero) was achieved by reviewing the entire series of sonographic images. A halo could be detected in 44 malignant tumors (88%) and in only seven benign tumors (14%) (sensitivity, 88%; specificity, 86%; positive and negative predictive values, 86% and 88%, respectively). The sonographic halo sign was particularly helpful in distinguishing hemangiomas (n = 29) from metastases (n = 43) (positive and negative predictive values, 95% and 87%, respectively). CONCLUSION. The results of this study suggest that the halo sign on sonograms is useful to distinguish benign from malignant isoechoic or hyperechoic tumors.  相似文献   

10.
With the increasing use of percutaneous transfemoral coronary angioplasty in conjunction with thrombolytic as well as anticoagulant therapy, the sonographic evaluation of groin masses, with particular emphasis on differentiating pseudoaneurysms from hematomas and other abnormalities, has become more common. Seventy-three sonograms of the groin in 60 patients (65 different groins) were reviewed retrospectively to determine the accuracy of duplex Doppler sonography in distinguishing femoral artery pseudoaneurysm (a surgical condition) from other causes of groin masses (e.g., hematomas) that are generally treated conservatively. Nineteen cases of pseudoaneurysm, 19 cases of hematoma, and 27 other conditions were studied. Of the 73 sonograms performed, 53 included duplex Doppler studies; one Doppler study was false-negative and two were possibly false-positive. The sensitivity, specificity, and accuracy of duplex Doppler sonography in the detection of femoral artery pseudoaneurysm was 95 +/- 5.8%, 94 +/- 6.4%, and 94 +/- 6.4%, respectively (95% confidence limit). We conclude that duplex Doppler sonography is of value in the differential diagnosis of groin masses.  相似文献   

11.
Yuh  WT; Zachar  CK; Barloon  TJ; Sato  Y; Sickels  WJ; Hawes  DR 《Radiology》1989,172(1):215-218
Magnetic resonance (MR) imaging was performed on 64 patients with 109 vertebral compression fractures, the cause of which could not be determined from plain radiographs. Twenty-five fractures were due to malignancy; 84 were caused by a benign process. In 22 of the 25 fractures caused by malignancy, MR images showed complete replacement of normal bone marrow, whereas 47 of the 61 benign fractures without history of trauma had complete preservation of normal bone marrow. The remaining 14 benign fractures had incompletely preserved bone marrow in a regular pattern. In two of the three remaining malignant fractures, the bone marrow replacement also was incomplete but with an irregular pattern. In cases of recent trauma or primary bone marrow abnormalities, the configuration and signal of remaining bone marrow were not useful in differentiating among malignancy, osteoporosis, and other benign processes. When criteria based on complete loss or preservation of marrow and marrow configuration in cases of incomplete loss were used, the accuracy in differentiating benign from malignant fractures was 94%. MR imaging may be a useful adjunct in differentiating benign from metastatic fractures and may provide information not available with other imaging methods.  相似文献   

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Differentiation of benign from malignant causes of vertebral compression fracture can be difficult at a single location. We studied 37 patients with solitary vertebral collapse (SVC) in the spine using magnetic resonance imaging (MRI). Sixteen of them were found to have a benign cause of SVC, while the remaining 21 were found to have malignancy. The following four MRI characteristics were investigated: ill- or well-defined margin of the intravertebral lesion (P < 0.005); pedicle involvement (P < 0.05); MR enhancement pattern (P < 0.005); and paravertebral soft tissue lesion (PSL) (P < 0.025). It was found that cases of malignant SVC tended to have an ill-defined margin, abnormal signal involvement of the pedicle, a marked and heterogenous MR enhancement pattern, and irregular nodular-type PSL. Pedicle change with expansile lesion totally excluded a benign cause. By using these criteria, we were able to differentiate benign or malignant causes of SVC accurately.  相似文献   

14.
This review discusses the usefulness of bedside lung ultrasound in the diagnostic distinction between different causes of acute dyspnea in the emergency setting, particularly focusing on differential diagnosis of pulmonary edema and exacerbation of chronic obstructive pulmonary disease (COPD). This is possible using a simple unit and easy-to-acquire technique performed by radiologists and clinicians. Major advantages include bedside availability, absence of radiation, high feasibility and reproducibility, and cost efficiency. The technique is based on analysis of sonographic artifacts instead of direct visualization of pulmonary structures. Artifacts are because of interactions between water-rich structures and air and are called “comet tails” or B lines. When such artifacts are widely detected on anterolateral transthoracic lung scans, we diagnose diffuse alveolar-interstitial syndrome, which is often a sign of acute pulmonary edema. This condition rules out exacerbation of COPD as the main cause of an acute dyspnea. The author did not receive personal or financial support from or has any affiliations or involvement with any organization with financial interest in the subject matter.  相似文献   

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OBJECTIVE: Our objective was to assess and compare the patterns of late enhancement (LE) in contrast-enhanced cardiac MRI caused by myocardial infarction and different myocardial diseases that are not related to ischemic infarction. MATERIALS AND METHODS: A total of 811 consecutive contrast-enhanced cardiac MRI studies performed for different indications were reviewed for left ventricular myocardial LE after gadopentetate dimeglumine administration. MRI studies were performed on a 1.5-T scanner using an inversion recovery turbo FLASH sequence (TR/TE, 8/4 msec; flip angle, 25 degrees). The LE pattern of ischemic infarction scar was compared with that in nonischemic myocardial disease. RESULTS: LE was found in 421 (52%) patients. In all patients with myocardial infarction, LE included the subendocardial layer. Nineteen patients without history of myocardial infarction and angiographically excluded coronary artery disease showed different patterns of LE caused by myocarditis, sarcoidosis, arrhythmogenic right ventricular dysplasia, cardiomyopathy, endomyocardial fibrosis, and iatrogenic scars after biopsy, ablation of septal hypertrophy, and myocardial laser revascularization. CONCLUSION: LE in contrast-enhanced cardiac MRI is not specific for ischemic infarction. LE in ischemic infarction always involves the subendocardial layer, whereas it does not necessarily do so in other myocardial diseases. Therefore, if LE omit the subendocardial layer, different nonischemic myocardial diseases have to be considered. The pattern of LE might be helpful for the differential diagnosis of myocardial disease and in distinguishing it from ischemic disease.  相似文献   

16.
In France, the term chemical or drug-assisted submission is usually defined as the rendering of a person vulnerable by the surreptitious administration of an active substance with the purpose of prejudicing the person or his/her possessions. If the harm is sexual assault, establishing the victim’s submission involves both proving that a dangerous substance was administered, providing material evidence of the infraction (the assault), i.e. the detection of traces in a physical examination and samples, and proving the absence of consent. We report the case of a woman who was sexually assaulted after having been surreptitiously administered methylenedioxymethamphetamine. In this special case, the woman remained in a state of vigilance (conscious) throughout, so there is doubt about whether or not she consented. In other words, the ability to consent is debatable.  相似文献   

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One of the most difficult on-site medical decisions is what steps to take when an athlete sustains a neck injury. A cautious examination is imperative and may involve assessing consciousness, pain, and spasm; evaluating neurologic symptoms; testing cervical range of motion; and deciding whether or not the player can return to play. Various signs and symptoms may herald serious injury and indicate the need to place the patient on a backboard before further assessment.  相似文献   

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Objectives

Cigarette smoking-induced airway disease commonly results in an overall increase of non-specific lung markings on chest radiography. This has been described as “dirty chest”. As the morphological substrate of this condition is similar to the anthracosilicosis of coal workers, we hypothesised that it is possible to quantify the radiological changes using the International Labour Organization (ILO) classification of pneumoconiosis. The aims of this study were to evaluate whether there is a correlation between the extent of cigarette smoking and increased lung markings on chest radiography and to correlate the chest radiographic scores with findings on CT studies.

Methods

In a prospective analysis a cohort of 85 smokers was examined. The cigarette consumption was evaluated in pack years (defined as 20 cigarettes per day over 1 year). Film reading was performed by two board-certified radiologists. Chest radiographs were evaluated for the presence of thickening of bronchial walls, the presence of linear or nodular opacities, and emphysema. To correlate the smoking habits with the increase of overall lung markings in chest radiography, the ILO profusion score was converted to numbers ranging from zero to nine. Chest radiographs were rated according to the complete set of standard films of the revised ILO classification.

Results

63/85 (74%) of the smokers showed an increase in overall lung markings on chest radiography; 32 (37%) had an ILO profusion score of <1/1, 29 (34%) had an ILO profusion score of <2/2 and 2 (2%) had an ILO score of ≥2/2. There was a significant positive linear correlation between the increase of overall lung markings on chest radiography and the cigarette consumption quantified as pack years (r=0.68). The majority of the heavy smokers (>40 pack years) showed emphysema; there was no significant difference between the prevalence of emphysema as diagnosed by CT (62%) or chest radiography (71%) (p<0.05).The most common findings in CT were thickening of bronchial walls (64%) and the presence of emphysema (62%) and of intralobular opacities (61%). Ground-glass opacities were seen in only 7% of our patients.

Conclusion

Bronchial wall thickening and intralobular opacities as seen in CT showed a positive linear correlation with the increase of overall lung markings on chest radiography.Tobacco smoke is the most important and well-known causative factor for the development of chronic bronchitis, bronchial cancer and emphysema [1]. Cigarette smoking also results in a focal accumulation of macrophages within the walls of the respiratory bronchioles and adjacent alveoli described as respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) [2-6]. The common finding of “dirty chest”, an overall increase in non-specific lung markings on chest radiography in such patients, is frequently identified in daily routine [7-10]. Remy-Jardin et al [11] found that the morphological substrate of cigarette smoking-induced changes in chest radiography were parenchymal micronodules and intralobular opacities comparable to the findings in anthracosilicosis of coal workers. Therefore, we hypothesised that it might be possible to quantify the smoking-induced changes of the lung using the International Labour Organization (ILO) classification [12].The aims of this study were to evaluate whether there was a correlation between the extent of cigarette smoking and increased lung markings in chest radiography and to correlate chest radiographic scores with findings on CT studies. To the best of our knowledge, an evaluation like this has not been described in the clinical literature so far.  相似文献   

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