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1.
HS O''Halloran K Draud M Minix AK Rivard PA Pearson 《Canadian Metallurgical Quarterly》1998,18(3):276-278
Adamantinoma of the long bones is a rare skeletal tumor and its MR features have seldom been reported. It is difficult to distinguish from other bone lesions (such as osteofibrous dysplasia or osteosarcoma) by means of conventional radiography and CT. MR imaging, however, may be useful in differentiating adamantinoma from such lesions. With this presentation of a typical case, we hope to draw the attention of radiologists to this lesion and contribute information on its MR appearance. 相似文献
2.
SA Cook RT Bronson LR Donahue N Ben-Arie MT Davisson 《Canadian Metallurgical Quarterly》1997,8(2):108-112
OBJECTIVE: To discuss the case of an 8-yr-old boy with an aneurysmal bone cyst of the right proximal humerus, including the features imaged on plain film radiography, computed tomography (CT), magnetic resonance imaging (MRI), including spin echo and fast field echo imaging. CLINICAL FEATURES: The patient suffered for 1 yr from intermittent but progressive pain in his right upper arm and shoulder area. There was no history of trauma or known systemic disease. There was decreased range of motion in abduction of the glenohumeral joint and pain on focal pressure along the deltoid muscle. A complete imaging evaluation consisting of plain film radiography, CT and MRI was performed, which revealed the classical imaging features of an aneurysmal bone cyst. An additional cystic lesion was detected by the MRI that was not appreciated on the plain films or CT. INTERVENTION AND OUTCOME: The patient was referred for biopsy to confirm the preliminary diagnosis of aneurysmal bone cyst. No treatment was instituted. CONCLUSION: Evaluation of aneurysmal bone cyst may be completed with CT scanning and more specifically with MRI MRI coronal T2, weighted images are advantageous for visualization of the main cystic lesion and any additional cysts. Fast field echo images show a better contrast between the cyst and bone marrow with extension of the cyst into the epiphysis as evident in this case. Follow-up studies revealed complete healing of the cyst with only residual densities in the humeral metaphyseal area. 相似文献
3.
The technique of moving-slit radiography for reduction of scattered radiation was investigated using a prototype moving-slit radiographic apparatus. Slit widths of 1-2 cm, when used in conjuction with an 8: 1 grid, were found to improve radiographic contrast by a factor of 2 in studies employing physical as well as anatomic phantoms. Use of the moving-slit technique at elevated kVp's was found to provide radiographic contrast as good as or better than that obtained in conventional low-kVp full-field techniques, but with a substantial reduction of patient exposure (factor of 2-4). Considerations in the design of an optimal multislit apparatus are discussed. Excessive tube loading is shown not to be a factor in such a system. 相似文献
4.
A Berstad T Hauksen OH Gilja K Hveem KA Undeland I Wilhelmsen TT Haug 《Canadian Metallurgical Quarterly》1997,32(3):193-197
PURPOSE: We investigated the capabilities of chest radiography in the elderly considering that the examination must meet the main clinical indications of this population and that it is necessary in the elderly because the correct clinical assessment is often difficult or impossible. MATERIALS AND METHODS: We reviewed the chest radiographs of 756 consecutive elderly patients admitted to our hospital from September 1 to October 31, 1996. If possible, chest radiographs were performed with the AMBER technique (156 patients, 20.7%); 240 patients (31.7%) underwent conventional radiography and the others frontal projections only (360 patients, 47.6%). T-MAT G RA Kodak high contrast films with Kodak Lanex green transmitting intensifying screens were used in all cases. The AMBER examinations of 48/156 patients with hemodynamic clinical indications were repeated with conventional frontal projections. Radiographic reports were made separately by different radiologists who considered especially the diagnostic accuracy of every examination in determining the venous overload of pulmonary circulation. RESULTS: Hemodynamic studies are the most frequent clinical indication of chest radiography in elderly patients (228/756 patients in our series, 30.2%); moreover, even if careful cardiac and pulmonary circulation studies are very important in these patients, only 52.4% of all radiographs could be made in two orthogonal projections. The blurred appearance of vascular landmarks indicating increased extravascular fluid is better depicted by conventional radiography (59.7% of cases) than by AMBER (40.3%). CONCLUSIONS: We conclude that the reduced pulmonary contrast obtained with the so-called "hard X-ray" technique poorly depicts the blurred appearance of pulmonary vessels in pulmonary venous overload. Moreover, "hard X-ray" techniques can be only sporadically used because elderly patients are often in very critical conditions, which prevents this type of examination. 相似文献
5.
J Belaiche 《Canadian Metallurgical Quarterly》1997,52(5):352-354
A pseudo-tumour due to metallosis is described in association with an iso-elastic hip replacement. This is a relatively rare lesion which may be difficult to diagnose. Scintigraphy and radiography may be helpful in distinguishing the lesion from a primary or secondary neoplasm, but the presence of osteolysis adjacent to the prosthesis will suggest the true nature of the lesion. 相似文献
6.
F Maire C Cellier JP Cervoni C Danel JP Barbier B Landi 《Canadian Metallurgical Quarterly》1998,22(11):958-960
Dieulafoy's disease is an unusual cause of gastrointestinal hemorrhage, reported to account for less than 2% of acute gastrointestinal bleeding episodes. Bleeding occurs from a defect in an unusually large submucosal artery, through a minute mucosal erosion. Endoscopic diagnosis is sometimes difficult, but primary endoscopic therapy may be successful and should be attempted. In most cases the lesion is found in the proximal stomach. Sixteen cases of Dieulafoy's lesion located in the colon have been reported in the literature but only nine have been confirmed by histology. We present the case of a 63 year-old male with Dieulafoy's lesion of the transverse colon which was diagnosed by endoscopy and confirmed by histology. 相似文献
7.
M Funke N Breiter KP Hermann JW Oestmann E Grabbe 《Canadian Metallurgical Quarterly》1998,71(845):528-534
Contact mammography with current photostimulable storage phosphors is hampered by its low spatial resolution. Detail visualization can be improved by geometric magnification radiography which enlarges small details to exceed inherent image noise. This study compares storage phosphor mammography using a dedicated direct magnification system with state-of-the-art conventional screen-film mammography. Storage phosphor direct magnification survey views (1.7x) and spot views (4x) were obtained with a prototype mammography unit providing focal spot sizes of 120-40 microns. Conventional technique screen-film survey views (1.1x) and spot views (1.8x) served as comparison. A contrast detail study and a receiver operating characteristic (ROC) analysis using an anthropomorphic breast phantom with superimposed microcalcifications was performed. Contrast detail resolution in the digital and conventional survey views were equivalent. For the spot views, contrast detail resolution was significantly higher with the digital technique (p < 0.001). ROC analysis of 400 observations demonstrated a significantly higher performance (p < 0.001) with digital images versus conventional screen-film mammograms. The area under the ROC curve (Az) in the digital survey views was 0.76 +/- 0.07 versus 0.59 +/- 0.02 in the conventional technique. In digital spot views, Az was 0.82 +/- 0.07 as compared with 0.66 +/- 0.04 in the conventional spot views. These results suggest that storage phosphor digital mammography in conjunction with direct geometric magnification technique may be superior to conventional screen-film mammography in the detection of microcalcifications. 相似文献
8.
PURPOSE: To compare the accuracy of digital luminescence radiography (DLR) and conventional film-screen radiography (FSR) in diagnosing fractures. MATERIAL AND METHOD: Both conventional and digital radiographs were acquired from a consecutive series of 57 patients with suspected wrist or hand fractures. The digital images were obtained with a 30% dose reduction. A ROC-analysis (receiver-operating characteristics) was performed. RESULTS: The area under the curve was 0.89 for conventional FSR, 0.93 for DLR, "gray scale" and 0.94 for DLR, "edge enhanced". CONCLUSIONS: Although its spatial resolution is lower, DLR provided better results than conventional FSR, when contrast processing algorithms were optimised for the specific clinical question. The edge-enhanced version was superior to the non-edge enhanced version. The reason for this seems to be the higher contrast resolution of DLR compared to FSR. 相似文献
9.
The objective of the study was to describe the ultrasonographic findings of urinary bladder urolithiasis and to determine the diagnostic value of the technique in feline lower urinary tract diseases (LUTD). Physical examination of the urinary system and routine clinicopathological analysis of the blood and urine were performed on 32 cats presented with clinical symptoms of LUTD. Cystosonography was done on all of the cats, while plain radiography was performed on 8 and double contrast cystography on 2 cats. Sonography of the bladder provided the following diagnoses: urolithiasis and chronic cystitis: 24 cases, chronic cystitis without urolithiasis: 4 cases, bladder neoplasm: 1 case, negative sonographic finding: 3 cases. Bladder calculi and/or plugs were diagnosed easily, up to a size of 2 mm, according to acoustic shadowing and/or reverberation and gravitation. When the bladder was empty, it was filled up with physiologic saline solution to visualise its contents more easily. Sonography proved to be a useful technique for diagnosing urinary bladder calculi and/or plugs even when they were radiolucent and for distinguishing among the different causes of LUTD. Although ultrasonography is a valuable diagnostic tool, radiography is still necessary to explore lower urinary tract diseases, especially when cystosonography provides negative results or urethral obstruction is suspected. 相似文献
10.
BACKGROUND: Proximal stomach by virtue of its property of accommodation acts as a reservoir for the ingested food, but its role in emptying and the factors modulating it remain unexplored. AIM: To assess the effects of distension and of feeding on proximal gastric tone. SUBJECTS: 14 healthy volunteers with no current or past history of any gastro-intestinal symptoms. METHODS: Isobaric changes in volume of the proximal stomach were recorded both during fasting and for the first 30 minutes after a meal. RESULTS: For a given degree of distension, the mean (SEM) intragastric pressure was consistently lower, immediately after meal ingestion (9.8 (1.1), mm Hg) than during fasting (12.9 (0.6) mm Hg; p < 0.01). Proximal gastric tone was continuously variable with a frequency of fluctuation of 0.9-1.3/minute and an amplitude of 16.8 (2.2) ml, superimposed upon slower higher amplitude fluctuations in baseline tone. These variations in tone were unaffected by the degree of gastric distension or by food. CONCLUSIONS: While proximal gastric tone decreases after meal ingestions consistent with accommodation, the fluctuations in tone are not an importance factor in the modulation of nutrient emptying from the proximal stomach in the immediate postprandial period. 相似文献
11.
BI Reiner EL Siegel KJ French RS Dentry WT Mazan MJ Maroney 《Canadian Metallurgical Quarterly》1997,17(6):1487-1495
The authors demonstrate the use of radiography in the investigation of an historic painting and describe the potential benefits of computed radiography compared with conventional screen-film radiography. The subject for the comparison was a 16 x 19-foot oil-on-canvas painting, Scipio Africanus Freeing Massiva, by Giovanni Battista Tiepolo. Radiographs of the painting were obtained by using a portable, industrial radiographic unit and both conventional screen-film and photostimulable phosphor plate cassettes. For this investigation, computed radiography had a number of advantages over screen-film radiography, largely due to its wider dynamic range and its capabilities for enhancing the digital images with image processing tools such as magnification, edge enhancement, colorization, and airbrushing. The ability to electronically combine images from the large painting into a single composite image file was extremely valuable, as this technique was much less cumbersome and resulted in much higher quality composite images than could be achieved with conventional radiography. An additional advantage of computed radiography includes the capability to easily archive and transmit these images in a digital format for subsequent review. 相似文献
12.
Chronic inflammatory bowel disease (CIBD) in children is represented mainly by ulcerative colitis (UC) and Crohn's disease (CD). Infectious forms, Beh?et's disease and eosinophilic gastroenteritis are not included in this study. UC and CD are difficult to diagnose and to treat, and require a multispecialistic approach including pediatric gastroenterologists, surgeons, radiologists, endoscopists and pathologists. Progress in diagnostic techniques--i.e., nuclear medicine procedures, conventional, duplex and color-Doppler US, and endoscopy--has increased our knowledge of these diseases and it has made their diagnosis easier, opening new therapeutic perspectives. In our paper, after mentioning the major clinical and radiologic features of CIBD, we report on the patients hospitalized in the Gaslini Institute from 1984 to 1994. Thirty-six patients (age range: 3,9 to 14 years) were examined with several imaging techniques--i.e., plain radiography, US, contrast studies and CT--according to the clinical presentation and behavior of the disease. X-ray studies played the leading role in imaging mucosal disease spread (double contrast studies) and monitoring "surgical" complications (plain radiography). These techniques, which were always combined with US and, in some cases, CT, are also a major tool to study extraluminal CIBD spread--i.e., fistulas, pseudotumors, lymph nodes, abscesses and mesenteric changes. Color-Doppler US may play a critical role in the differential diagnosis of these and other small and large bowel pathologic conditions. The most typical CD patterns in bowel disease are listed in the paper, to give a contribution to the differential diagnosis of the chronic abdominal pain syndrome which is a very common condition in children. 相似文献
13.
A Ragozzino G Rossi S Esposito S Giovine M Tuccillo 《Canadian Metallurgical Quarterly》1996,92(6):682-686
The definition "osteochondritis dissecans" of the talus improperly includes a variety of diseases involving the chondral surface of the talus dome and the relative subchondral bone. To investigate the CT diagnostic potentials in the study of these conditions, 35 patients complaining of a "painful ankle" were examined with plain radiography and axial and direct paracoronal CT over a 2-year period. Twelve patients were then examined with double contrast CT arthrography with air and iodated contrast agents. CT diagnostic accuracy was assessed evaluating the following parameters: the presence and extent of the subchondral bone fragment, the presence of residual bone fragment attachment at the lesion base or its intraarticular dislocation, the presence of subchondral bone cysts, of chondral surface lesions and, finally, of capsular and ligamentous damage. All the patients with CT findings of osteochondral conditions of the talus dome were submitted to arthroscopic examination/treatment and/or surgical arthrotomy. Baseline CT exams accurately depicted all the lesions, except for early (grade I) lesions. Moreover, the administration of intraarticular contrast agent (CT arthrography) increased the diagnostic accuracy in articular cartilage studies. Therefore, the authors believe baseline CT on the orthogonal planes to represent an effective tool for the staging of osteochondral talar lesions and for accurate treatment planning. 相似文献
14.
Cartilaginous disorders of the thorax can arise in the parenchyma, airways, chest wall, and axial skeleton. At radiography, pulmonary hamartoma is characterized by "popcorn" calcification or fat density, either of which is diagnostic. Bronchiectasis is best demonstrated at high-resolution computed tomography (CT) and has a "tramline" or "signet ring" appearance. Tracheopathia osteochondroplastica appears at CT as multiple sessile submucosal nodules with or without calcification along the cartilaginous portion of the trachea. In relapsing polychondritis, the trachea and mainstem bronchi have diffuse or focal thickening with luminal narrowing at radiography. Costochondritis of the chest wall has become more prevalent with increased intravenous drug abuse and may be demonstrated at CT as soft-tissue swelling along with underlying cartilaginous fragmentation and bone destruction. Enchondromas are expansile and may display a calcified cartilaginous matrix at radiography. In osteochondroma, the thickness of the cartilaginous cap determines the likelihood of malignant degeneration. At radiography, chondroblastomas have a round contour, sharp margins, and cortical scalloping, whereas chondrosarcomas are large masses with indistinct margins, cortical breakthrough, and soft-tissue extension. By identifying either a process affecting a cartilage-containing structure or a cartilaginous matrix within a lesion, the chest radiologist may be able to narrow the list of differential diagnostic possibilities substantially. 相似文献
15.
Assessment of maternal pelvic dimensions is usually considered necessary where vaginal delivery is contemplated in a breech presentation or if reduced pelvic dimensions are suspected in a current or previous pregnancy. Pelvimetry techniques include computed tomography (CT), conventional radiography, digital fluorography and magnetic resonance imaging (MRI). The first three techniques result in a radiation dose to mother and fetus which, depending on how the technique is performed, can vary by up to 40-fold. Of the techniques using X-rays, CT pelvimetry with a lateral scanogram generally gives the lowest radiation dose and conventional radiography using an air gap technique with a single lateral view is a relatively low-dose alternative where CT is not available. A questionnaire was sent to 227 hospitals during 1993 and 1996 to assess whether there was a move towards lower dose techniques of pelvimetry. The results show a trend away from conventional pelvimetry (48.4% in 1993 to 28% in 1996) with a small proportion of centres using MRI (4%) in 1996. Of the centres still using conventional pelvimetry, relatively few were using a low-dose air-gap technique (2.1% in 1993 to 10.9% in 1996). An increasing majority of centres were using one-view CT (69.3% in 1993 and 80.4% in 1996) but a significant proportion were still performing more than one view. This study shows that there was a move towards lower dose techniques of pelvimetry but that there were still many hospitals that had not implemented a policy of reducing radiation exposure in these patients. 相似文献
16.
The purpose of this study was to assess the accuracy of lateral cervical spine radiography in the detection of degenerative atlantoodontoid (AO) osteoarthritis, with CT as gold standard. In 50 patients, lateral radiographs and CT of the AO joint were blindly and independently graded by two radiologists: 0 = normal, 1 = mild degenerative disease, 2 = severe degenerative disease. Radiography was most accurate in distinguishing absent or mild disease from severe disease (83% sensitivity, 84% specificity). Sensitivity in distinguishing absent disease from mild or severe disease was 87%. Specificity, however, was low (52%), due to overestimation of the degenerative involvement on radiography. It is concluded that conventional radiography is a useful technique in screening for AO osteoarthritis, especially in severely degenerated joints. However, CT provides the best radiographic detail necessary for accurate diagnosis. 相似文献
17.
F Aftab HS Stoldt A Testori A Imperatori M Chinol G Paganelli J Geraghty 《Canadian Metallurgical Quarterly》1996,22(4):381-388
Radioimmunoguided surgery is a technique that aims to delineate the extent of epithelial neoplasms (primary/recurrent) and their spread (local, regional, and distant) which are not adequately visualized by conventional imaging techniques. The target lesion binds radiolabelled, tumour-associated monoclonal antibodies which are administered in the days before surgery and which bind to the target lesion. The radiotracer is detected intraoperatively using a hand-held gamma detecting probe. This identifies the extent of the tumour, involvement of lymph nodes or other organs and may allow a more complete surgical clearance of the tumour. This article provides a basic understanding of the RIGS (radioimmunoguided surgery) technique, the monoclonal antibodies which are used and outlines the advantages and limitations of this technique. 相似文献
18.
OBJECTIVE: Our objective was to determine the predictive value of specimen radiography for large core (14-gauge) needle biopsy of noncalcified breast masses. SUBJECTS AND METHODS: Eighty-four biopsies of 83 breast masses yielded 403 specimens. Specimens showing dense material on specimen radiography were predicted to be diagnostic; specimens showing intermediate- or low-density material were predicted to be nondiagnostic. Specimen radiographic and histopathologic findings were correlated for each specimen using vital dyes to mark individual specimens. RESULTS: Of the 403 specimens, 307 (76%) contained diagnostic material representative of the lesion, with a specific diagnosis achieved for 82 (99%) of 83 lesions (62 benign, 20 malignant). Of the 293 passes containing dense material, 268 (91%) proved to be diagnostic; 11 (18%) of 62 specimens containing only low-density material proved to be diagnostic. Of the 25 (9%) of 293 specimens containing radiographically dense but nondiagnostic material, 18 (72%) showed focal fibrosis and had missed the lesion; 15 (83%) of 18 such specimens were obtained in dense parenchyma. The positive predictive value of specimen radiography was 13 (100%) of 13 in fatty breasts; 77 (96%) of 80 in breasts with minimal scattered fibroglandular elements; 91 (94%) of 97 in heterogeneously dense breasts; and 35 (70%) of 50 in breasts with extremely dense parenchyma. Of the 16 lesions sampled stereotactically, specimen radiography helped assess the inadequacy of initial sampling in three (19%). In six (9%) of 68 sonographically guided biopsies, only one or two specimens could be obtained; specimen radiography helped us predict whether material was adequate for diagnosis. CONCLUSION: Radiography of core specimens obtained from noncalcified breast masses accurately reveals the adequacy of sampling unless the breast parenchyma is extremely dense. Such immediate assessment can help ensure adequate material from lesions that are difficult to biopsy and can thereby improve the diagnostic yield of large core needle breast biopsy. 相似文献
19.
H Coon M Myles-Worsley J Tiobech M Hoff J Rosenthal P Bennett F Reimherr P Wender P Dale A Polloi W Byerley 《Canadian Metallurgical Quarterly》1998,3(6):521-527
OBJECTIVES: This study was performed to demonstrate the value and durability of intraoperative retrograde angioplasty for stenotic lesions of the aortic arch branches at the time of carotid endarterectomy for the treatment of tandem proximal and bifurcation carotid lesions. DESIGN: Retrospective analysis of the clinical data. METHODS: Forty-four patients were included in this study when they presented with symptomatic extracranial vascular disease due to stenosis of both a proximal aortic arch branch and carotid bifurcation disease. Tandem disease was detected in the vascular laboratory and confirmed by angiography. Each patient was subjected to conventional carotid endarterectomy, and at the time of operation, the proximal lesion was subjected to transluminal angioplasty through the endarterectomy arteriotomy (brachiocephalic 24; left common carotid 15; right common carotid artery five). Patients were then followed up clinically and by non-invasive tests at 6-monthly intervals. RESULTS: Forty-three successful dilatations were achieved. The single initial technical failure was due to heavy calcification of a brachiocephalic artery. In the follow-up period restenosis was noted in four patients. All restenosis occurred within 24 months. No restenosis at the angioplasty site was noted on subsequent follow-up of the remaining 39 patients. No perioperative stroke or death was encountered. A surprisingly high mortality rate was noted on follow-up in this group of patients, suggesting the presence of more aggressive and advanced diffuse vascular disease. CONCLUSION: Retrograde intraoperative angioplasty of the proximal component of a tandem extracranial lesion has in this series proven to be a safe and durable therapeutic option. This technique has an acceptable restenosis rate in a subset of patients who have been demonstrated to have a shortened life expectancy and a high mortality rate in the follow-up period. 相似文献
20.
The aim of this study was to determine whether insulin-induced relaxation of the proximal stomach after proximal gastric vagotomy is mediated by vagal release of antral gastrin. In six conscious, fasted dogs following proximal gastric vagotomy, the effects of intravenous insulin (1 U/kg) and intravenous gastrin (1 microg/kg) on proximal gastric motility, as measured by a gastric barostat, on plasma glucose, and on plasma gastrin, as measured by radioimmunoassay, were assessed 1 hour before and for 2 hours after injection. The effects of a cholecystokinin (CCK)-A receptor antagonist and a CCK-B receptor antagonist on insulin-induced or gastrin-induced relaxation of the proximal stomach and on plasma glucose and gastrin were also determined. Intravenous insulin decreased plasma glucose (before [mean +/- SD], 97 +/- 5 mg/dl vs. after, 45 +/- 3 mg/dl; P <0.05), increased plasma gastrin (before, 240 +/- 59 pg/ml vs. peak after, 387 +/- 85 pg/ml; P <0.05), and relaxed the proximal stomach (100% +/- 0% barostat volume vs. 202% +/- 15% volume; P <0.05). Exogenously administered gastrin also relaxed the proximal stomach without decreasing plasma glucose. CCK-B blockade diminished, but did not abolish, the gastric relaxation caused by insulin or gastrin, whereas CCK-A blockade had little effect. It was concluded that insulin-induced relaxation of the proximal stomach after proximal gastric vagotomy is mediated, in part, by vagal release of antral gastrin. 相似文献