Sonography of diabetic muscle infarction with MR imaging, CT, and pathologic correlation

OBJECTIVE: The purpose of this article is to describe the sonographic findings of muscle infarction in patients with diabetes with MR imaging, CT, and pathologic correlation. CONCLUSION: Sonographic findings of diabetic muscle infarction include internal linear echogenic structures coursing through the lesion; an absence of internal motion or swirling of fluid with transducer pressure; and a lack of a predominately anechoic area. We believe that these sonographic characteristics may help differentiate diabetic muscle infarction from abscess or necrotic tumor. Additional study involving direct sonographic comparison of these entities is needed to establish the role of sonography in diagnosis of diabetic muscle infarction.     

Evaluation of CT findings for diagnosis of pleural effusions

Computed tomography studies are usually used to assess patients with pleural effusions, and radiologists should be aware of the significance of different CT findings for the diagnosis of the effusion. The purpose of this study was to evaluate CT findings for etiological diagnosis of pleural effusions. Contrast-enhanced CT of the chest of 211 patients with pleural effusion of definite diagnosis were evaluated. The CT images were evaluated for the presence and extent of pleural effusion, thickening or nodules, extrapleural fat and other changes in the mediastinum or lung. The CT scans were read by two independent observers and correlation between them was evaluated. Comparison of CT findings between benign and malignant effusions, between exudates and transudates, and between empyemas and the other parapneumonic effusions were carried out. Kappa values for most CT findings were > 0.85. Loculation, pleural thickening, pleural nodules, and extrapleural fat of increased density were only present in exudative effusions. Multiple pleural nodules and nodular pleural thickening were the only pleural findings limited to malignant pleural effusions. The signs were also more frequently seen in empyemas than in other parapneumonic effusions. Computed tomography findings can help to distinguish between transudates and exudates. Although there is some overlap between benign and malignant pleural effusions, pleural nodules and nodular pleural thickening were present almost exclusively in the latter. Although differences between CT findings of empyemas and the other parapneumonic effusions exist, there is no finding which can definitely differentiate between them. Received: 27 January 1999; Revised: 24 June 1999; Accepted: 24 August 1999     

Sonography of malignant pleural effusion

Two hundred and ten patients with exudative pleural effusion were studied by ultrasound for sonographic signs of pleural carcinomatosis. Images were evaluated for echoes within the fluid, septations, sheet-like or nodular pleural masses, and associated lesions of the lung. Our results showed that sonographic findings of echogenic or septated fluid were unspecific for malignancy. Only the evidence of pleural masses was characteristic of malignant effusion. Ultrasound of the chest should therefore be carried out before invasive diagnostic procedures are planned. Received 31 May 1995; Revision received 12 September 1996; Accepted 14 January 1997     

Pleural calcification with persistent effusion

Chronic persistent pleural effusions were observed in 22 out of 140 patients with calcification involving the parietal and visceral pleurae. If no effusion is present, the two adjacent calcified pleurae may adhere together; and conversely, in the presence of fluid the pleural layers are separated, producing more than one linear density on the radiograph. Pleural thickening can exceed 2 cm. In patients with calcified fibrothorax, the calcified parietal pleura is separated from the inner thoracic wall by fat whether an effusion is present or not. The value of CT and sonography in the detection of persistent effusions is discussed.     

Real-time sonography of pleural opacities

Fifty patients with radiographic pleural or pleural-based opacities were examined with high resolution real-time sonographic sector scanning. In 90% of cases selected for thoracentesis, fluid sufficient for diagnosis was obtained. Complex, septated pleural loculations contained an exudative effusion in 74% of the patients, while anechoic areas yielded exudative and transudative effusions with almost equal frequency. The use of real-time scanning is stressed because of greater flexibility and shorter examination time compared to compound scanning, and its utility for portable scanning on critically ill patients.     

Transudative vs exudative pleural effusions: differentiation using Gd-DTPA-enhanced MRI

The aim of this study was to investigate the capability of Gd-DTPA-enhanced MRI to differentiate between exudative and transudative pleural effusions. An MRI examination was performed on 22 patients with different types of pleural effusion (10 transudative and 12 exudative effusions). T1-weighted SE images were obtained before and 20 min after administration of Gd-DTPA (0.1 mmol/kg). The degree of enhancement of pleural effusions was evaluated both by visual assessement and by quantitative analysis of images. None of 10 transudative effusions showed significative enhancement, whereas 10 of 12 exudative effusions showed enhancement (sensitivity 83 %, specificity 100 %, positive predictive value 100 %). The postcontrast signal intensity ratios (SIRs) of exudates were significantly higher than corresponding precontrast ratios (P = 0.0109) and the postcontrast SIRs of exudates were significantly higher than those of transudates (P = 0.0300). Exudative pleural effusions show a significant enhancement following administration of Gd-DTPA. We presume that this may be caused by increased pleural permeability and more rapid passage of a large amount of Gd-DTPA from the blood into the pleural fluid in case of exudative effusions. In our limited group of patients, signal enhancement proved the presence of an exudative effusion. Absence of signal enhancement suggests a transudate, but does not exclude an exudate. Received 9 April 1996; Revision received 12 August 1996; Accepted 4 October 1996     

Pleural and parenchymal lung diseases from asbestos exposure. CT diagnosis

INTRODUCTION: We report the CT findings of parenchymal and pleural diseases in a group of patients with a history of asbestos exposure, excluding lung cancer (which is not typical in this subjects) and asbestosis (which is a parenchymal fibrosis). MATERIAL AND METHODS: We retrospectively reviewed a series of CT examinations (conventional, helical and high resolution scans) of 21 patients examined from 1995 to 1999. They had pleural plaques (10), round atelectasis (2) and malignant pleural mesothelioma (9). All patients had a history of direct or indirect asbestos exposure, except one with malignant pleural mesothelioma. We evaluated the following CT findings: nodular, plaque or uniform pleural thickening; pleural calcifications; pleural thickening less or greater than 1 cm; pleural margins (regular, polycyclic, spiculated); localization (uni/bilateral hemithorax); distribution (upper, medium or lower region); pulmonary, mediastinal and diaphragmatic involvement; fissural involvement; pleural effusion; lymph node enlargement; lung mass with the comet-tail sign; lung volume (normal, reduced, increased). RESULTS: Pleural plaques were always bilateral and less than 1 cm thick, with calcifications in 80% of the cases. Margins were always regular, polycyclic in 40% of the patients and never irregular. The pulmonary pleura in the mid-chest was involved in cell cases the diaphragmatic pleura in the 50% of the cases and the upper and lower regions in 60% and 80% of the patients, respectively. Round atelectasis (3 cases in 2 patients) was always shown as a parenchymal mass in the lower lobes, posteriorly or posteromedially, with adjacent pleural thickening; its diameter ranged 4.4-6 cm and there was the comet-tail sign. In malignant pleural mesothelioma we always found pleural effusion, with unilateral pleural effusion being the only sign in 2 patients. Other findings were pleural nodules (77.7%), with spiculated (22.2%) and polycyclic (77.7%) margins, more than 1 cm in diameter. The disease was always unilateral. The parenchymal pleural was involved in 77.7% of the cases while the mediastinal and diaphagmatic pleura were involved in 44.4% of the patients. Fissural involvement was demonstrated in 66.6% of the patients. Lymph nodes were enlarged in 66.6% of the cases. The volume of the affected hemithorax was increased (22.2%), decreased (44.4%) or normal (33.3%). DISCUSSION AND CONCLUSIONS: The presence of pleural plaques is a specific sign of asbestos exposure. Round atelectasis may also indicate asbestos exposure, but it can be found in many diseases with pleural inflammation, such as tuberculous effusion, trauma, pulmonary infarct, congestive heart failure, coronary artery bypass. The CT patterns of these two diseases are typical and no other finding is necessary to confirm the diagnosis. CT-guided needle biopsy is needed only if the round atelectasis has an atypical appearance on CT images, that is without the comet-tail sign. Malignant pleural mesothelioma is strongly associated with previous occupational exposure and presents typical CT findings only in an advanced stage (irregular and nodular pleural thickening, pleural effusion, mediastinal and pulmonary contraction for tumor encasement, parenchymal and lymph node metastases), but the differential diagnosis with pleural metastatic disease can be difficult. CT plays an important role in tumor assessment but biopsy is necessary for lesion characterization.     

Chest sonography. Differentiation of pulmonary consolidation from pleural disease

Ultrasonography was used to evaluate 53 patients with equivocal juxta-diaphragmatic and/or lateral densities in chest radiographs. An air bronchogram, fluid bronchogram, and scattered echogenic foci due to residual air in the consolidated lung parenchyma were used as US criteria of pulmonary parenchymal consolidation. One or more of these signs were observed in 39 patients with a clinical or bacteriologic diagnosis of pneumonia. The US air bronchogram was seen in 32 of the 39 patients (82%), the fluid bronchogram in 37 patients (94%) and the scattered echogenic foci in 30 (77%). In 14 patients, pleural effusion was diagnosed sonographically and verified by aspiration of fluid. The final diagnoses in these cases were pulmonary tuberculosis in 11 patients, staphylococcal empyema in 2, and tuberculous empyema in one patient. It is concluded that US criteria provide a useful differentiation of pulmonary parenchymal consolidation from pleural effusion.     

The pathogenesis, radiologic evaluation, and therapy of pleural effusions

Radiology has played a pivotal role in the management of patients with pleural effusions. By confirming the presence of an effusion and providing information regarding the size and distribution of fluid, chest radiography greatly facilitates initial diagnostic thoracentesis. Identification of even small effusions is important because these commonly occur and may have clinical significance. The development of improved antibiotics and a wider range of interventional techniques has increased the reliance on the radiologic imaging of pleural disease in order to plan appropriate therapy. The newer imaging modalities of CT and sonography have proved to be particularly valuable in detecting small effusions and demonstrating single or multiple loculations. Additional features, such as the degree to which a pleural process has become organized and whether there is adjacent lung parenchymal disease, are well assessed on CT. Experience with MR has been limited, but preliminary data suggest that it may be a valuable addition and/or alternative to CT.     

The CT appearance of pleural and extrapleural disease in lymphoma.

OBJECTIVE: Pleural effusions in patients with lymphoma that are assumed to be related to malignancy are attributed to either lymphatic obstruction by tumour with resultant decreased clearance of pleural fluid, or direct tumour involvement of the pleura. The purpose of our study was to determine how often pleural or extrapleural disease was detected by computed tomography (CT) of patients with pleural effusions and primary or recurrent lymphoma. METHODS AND MATERIALS: We reviewed CT examinations showing evidence of pleural effusion in 61 patients with a diagnosis of primary or recurrent lymphoma and no history of other systemic disorders, including infection. The study population consisted of patients with non-Hodgkin's lymphoma (n = 44) or Hodgkin's disease (n = 17); both primary disease (n = 11) and recurrent disease (n = 50) were represented. Each CT examination was evaluated for the presence of disease involving the visceral and parietal pleura and extrapleural space, mediastinal adenopathy, and pulmonary parenchymal disease. RESULTS: Fourteen patients (23%) (nine with non-Hodgkin's lymphoma and five with Hodgkin's disease) had parietal pleural disease (thickening or nodules). Eighteen patients (30%) (14 with non-Hodgkin's lymphoma, four with Hodgkin's disease) had tumour or enlarged lymph nodes in the extrapleural space. Forty-three patients (70%) had mediastinal lymphadenopathy. Patients who received intravenous contrast did not have evidence of visceral pleural abnormalities or underlying pulmonary parenchymal disease. CONCLUSION: Forty-one percent of the patients with lymphoma and pleural effusions had CT evidence of pleural and/or extrapleural disease. The majority of the patients with extrapleural disease had adjacent posterior mediastinal disease.     

不伴肝硬化的病毒性肝炎相关性胸腔积液的临床特点

 目的 探讨不伴肝硬化的病毒性肝炎相关胸腔积液的临床特点。方法 回顾性分析2003-01至2018-03在北京积水潭医院收治的不伴肝硬化的病毒性肝炎合并胸腔积液患者的临床资料,包括生命体征、血生化及微生物学检查,胸部影像学检查,胸腔积液的生化、常规、微生物学检查,行胸腔镜检查的患者,以及病理学检查结果。结果 共有132例病毒性肝炎合并胸腔积液病例入选,排除因心、肺、肾等脏器病变,以及肝硬化、结核、肿瘤、风湿等引起的胸腔积液后,剩余6例。胸腔积液为渗出液,单侧或双侧,少量至中量。其中2例行胸腔镜检查,壁层胸膜纤维素性渗出、局部充血,少量粘连。壁层胸膜病理检查发现:纤维细胞和纤维母细胞增生,被覆纤维素性渗出及坏死;有散在的淋巴细胞浸润;大片新鲜和陈旧性出血。结论 未出现肝硬化和低蛋白血症的病毒性肝炎也可引起胸腔积液。病毒性肝炎治愈或好转后,胸腔积液可以吸收或好转。     

Pulmonary radiation reaction in the treatment of carcinoma of the breast.

Chest roentgenograms were performed regularly before and a long time after radiotherapy in 157 patients with cancer of the breast. Radiation-induced parenchymal changes were demonstrated in 73 per cent of the patients and pleural effusions in about 10 percent. Total regression of the parenchymal changes were extremely rare, but a slight decrease in the volume of the affected lung was normal. The radiation-induced pleural effusion had no special characteristics, but, with one exception, it occurred simultaneously with radiation-induced parenchymal infiltrates, and it did not increase in quantity in any case.     

Efficacy of CT in diagnosis of transudates and exudates in patients with pleural effusion

PURPOSE

We aimed to evaluate the efficacy of multidetector computed tomography (CT) imaging in diagnosis of pleural exudates and transudates using attenuation values.

MATERIALS AND METHODS

This retrospective study included 106 patients who were diagnosed with pleural effusion between January 2010 and June 2012. After the patients underwent chest CT, thoracentesis was performed in the first week. The attenuation values of the pleural effusions were measured in all patients.

RESULTS

According to Light’s criteria, 30 of 106 patients with pleural effusions had transudates, and the remaining patients had exudates. The Hounsfield unit (HU) value of the exudates (median, 12.5; range, 4–33) was significantly higher than that of the transudates (median, 5; range, 2–15) (P = 0.001). Additionally, when evaluated by disease subgroups, congestive heart failure and empyema were predictable in terms of median HU values of the pleural effusions with high and moderate sensitivity and specificity values (84.6% and 81.2%, respectively; 76.9% and 66.7%, respectively). Compared with other patients, the empyema patients had significantly more loculation and pleural thickening.

CONCLUSION

CT attenuation values may be useful in differentiating exu-dates from transudates. Although there is an overlap in most effusions, exudate can be considered when the CT attenuation values are >15 HU. Because of overlapping HU values, close correlation with clinical findings is essential. Additional signs, such as fluid loculation and pleural thickness, should be considered and may provide further information for the differentiation.Pleural effusion is a common clinical problem; indeed, it can arise from many diseases (1, 2). The first step in assessing a pleural effusion is to decide whether the pleural fluid is a transudate or an exudate (3). Transudate is caused by imbalances in hydrostatic and oncotic forces. It results from diseases such as heart failure, kidney failure, and cirrhosis. However, an exudate occurs when local factors influencing the accumulation of pleural fluid are altered. Exudates can be caused by clinical conditions such as pneumonia, malignancy, and thromboembolism (4).Although clinical and radiological findings may provide significant evidence about the cause(s) of pleural effusion(s), it may still be necessary to evaluate some cases with diagnostic thoracentesis (4, 5). Clinically, exudative effusion can be successfully separated from transudative effusion using Light’s criteria. The nature of the pleural effusion is based on diagnostic thoracentesis (1, 2). However, computed tomography (CT) can be used to evaluate the nature of pleural effusions to avoid the complications of thoracentesis (6, 7). Features such as pleural nodules, pleural thickening, loculation, extrapleural fat tissue thickness, and effusion density can be evaluated by CT to discriminate between exudates and transudates (8). Only two reported studies have examined CT attenuation values in patients with pleural effusions (9, 10); these showed different attenuation values for evaluation of pleural effusions.The aim of the present study was to evaluate the efficacy of multidetector CT (MDCT) images in diagnosing pleural exudates and transudates using attenuation values.     

The anechoic crescent in abdominal aortic aneurysms: not a sign of dissection

In six cases, abdominal aortic aneurysms simulated dissections because an anechoic crescent was seen peripheral to the echogenic intraluminal thrombus. Thrombus can easily be identified by sonography, but the layered echogenic and anechoic appearance has not been described. Three of these cases are presented to illustrate this sonographic pattern of thrombus so that it will not be misinterpreted as a dissection. CT scans were performed on all three patients and an arteriogram and surgery in one, all of which confirmed that these were not dissections but two layers of thrombus with the intima peripheral to the anechoic layer. At surgery, the anechoic layer medial to the intima in one case proved to be serosanguinous fluid and, therefore, likely liquefaction of the clot.     

Bacterial meningitis in infants: sonographic findings

A retrospective study was performed on 78 patients (newborn to 2 years old) with clinically proved bacterial meningitis. Sonograms were obtained during the acute illness and medical records were reviewed. The spectrum of sonographic features of meningitis included normal scans (30 patients), ventriculomegaly (11 patients), echogenic sulci (31 patients), extra-axial fluid collections (26 patients), abnormal parenchymal echogenicity (9 patients), evidence of ventriculitis (5 patients), and brain abscess (1 patient). In 46 patients, correlation between the sonographic findings and neurologic outcome on clinical follow-up (6 months to 4 years) was made. Findings of abnormal parenchymal echogenicity and/or moderate-to-marked ventriculomegaly were associated with significant neurologic sequelae; however, echogenic sulci and small extra-axial fluid collections did not appear to have any prognostic significance. Twenty-nine of the 78 patients had sonography without clinical indication of complications of meningitis, and in no patient was a significant abnormality found. Our study suggests that sonography is indicated only when there is clinical suspicion of complications.     

The air bronchogram: sonographic demonstration

A new sonographic pattern of pulmonary consolidation associated with air-filled bronchi in children is presented. The consolidated area of the lung is usually hypoechoic, poorly defined, and wedge-shaped. The air-filled bronchi produce linear, high-amplitude branching echoes that converge toward the lung root. Posterior acoustic shadowing and reverberation artifacts are seen accompanying the proximal large bronchi. A comparative study is presented in which 30 pediatric patients with clinical and radiographic evidence of pneumonia were sonographically evaluated. Twenty-eight patients were successfully examined with sonography. The cases were divided into three groups: (1) consolidated lung without pleural effusion (19 patients); (2) consolidated lung with small pleural effusion (five patients); and (3) consolidated lung with partial compression atelectasis due to large pleural effusion (four patients).     

Sonography of adenomyomatosis of the gallbladder: radiologic-pathologic correlation

Sonograms of six patients with adenomyomatosis of the gallbladder were reviewed and correlated with oral cholecystographic and pathologic findings. The gallbladder was visualized in four of the six patients by oral cholecystography, which also revealed intramural diverticula. Five of the six patients showed sonographic evidence of diffuse or segmental thickening of the gallbladder wall and intramural diverticula, seen as anechoic or echogenic foci within the wall. Intramural diverticula containing bile appeared as anechoic spaces; those containing biliary sludge or gallstones appeared as echogenic foci with or without acoustic shadows or reverberation artifacts. There was good correlation between sonographic and pathologic findings in three patients. The authors conclude that adenomyomatosis of the gallbladder should be suspected when (a) there is diffuse or segmental thickening of the gallbladder wall and (b) intramural diverticula are seen as anechoic or echogenic foci with or without associated acoustic shadows or reverberation artifacts.     

The variable sonographic appearances of ovarian teratomas: correlation with CT

To better understand how the internal composition of ovarian teratomas influences their sonographic features, we compared their sonographic and CT appearances in 23 cases. Sixteen lesions had a mixed echo texture, with hypoechoic as well as echogenic components; two were anechoic and five were entirely echogenic. Correlation with the CT images showed that the fat present in most teratomas had variable sonographic appearances. Pure sebum was anechoic or hypoechoic, but fat intermixed with hair strands was echogenic and often attenuated the sound beam because of the numerous tissue interfaces created within the mass. The hypoechoic component of the teratoma corresponded, on CT, to low-attenuation fat in 12 tumors and to fluid in five. Most teratomas contained a dermoid plug, a protuberance arising from the tumor wall and containing hair follicles and often fragments of bone or teeth. On sonography, all dermoid plugs were seen as an echogenic mass, often associated with distal acoustic shadowing and protruding into the hypoechoic portion of the teratoma. When the dermoid plug was large and occupied most of the tumor, the entire teratoma appeared echogenic, with no discernible anechoic component. We found that three factors greatly affected the sonographic appearance of ovarian teratomas: the size of the dermoid plug, the presence and location of calcified elements, and the histologic composition of the fatty component.     

Thoracic CT findings in long-term hemodialysis patients

PURPOSE: To evaluate thoracic CT findings of long-term hemodialysis patients. MATERIAL AND METHODS: Thoracic CT findings of 117 uremic patients (61 men, 56 women) with complaints of cough, dyspnea, low-grade pyrexia, malaise, weight loss, and profuse perspiration were retrospectively documented. RESULTS: Atelectasis (60%), cardiomegaly (60%), pleural effusion (51%), vascular congestion (44%), parenchymal consolidation (38%), parenchymal scarring-fibrosis (31%), and lymphadenopathy (29%) were the most common CT findings in the thoraces of the long-term hemodialysis patients. Staphylococcus aureus was detected in 13 patients (11%) who had parenchymal infiltration. Thoracic tuberculosis was identified in 15 patients (13%), 11 of these cases being confined to the lung parenchyma, 3 to the pleura, and 1 involving the pleura and pericardium. CONCLUSION: In patients under long-term hemodialysis treatment, parenchymal consolidation, secondary to infectious agents such as S. aureus and Mycobacterium tuberculosis, is the most important CT finding since these lesions can be detected and treated successfully if they are considered as etiologic factors early on.     

The sonographic features and implications of fetal pleural effusions

Pleural fluid was detected by ultrasound in three fetuses as an anechoic area surrounding the echogenic fetal lung. In one fetus the underlying lung was small, immobile and of abnormal contour; death occurred in the neonatal period and the lung was found to be hypoplastic. In two other fetuses the lungs appeared sonographically normal, being mobile with normal contours. Both survived, one following spontaneous intra-uterine resolution of the effusion and the other after early neonatal intervention prompted by the antenatal diagnosis. Sonography can detect pleural fluid in utero and may permit differentiation between normal underlying lung and pulmonary hypoplasia. We recommend serial scanning to detect early adverse effects of pleural effusion upon the fetus and to plan management changes.