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951.
MR imaging of the male pelvis 总被引:2,自引:0,他引:2
Barentsz JO Engelbrecht MR Witjes JA de la Rosette JJ van der Graaf M 《European radiology》1999,9(9):1722-1736
Prostate and urinary bladder cancer are the most frequently encountered malignancies of the urinary tract. Appropriate use
of the different imaging techniques is crucial for accurate assessment of prognosis and for the development of appropriate
treatment planning. Especially determination of local tumor extension and detection of nodal or bone metastases is extremely
important. In this regard MR imaging is the most promising imaging technique. Therefore, in this review its role in staging
these malignancies is evaluated and compared with clinical staging, and other imaging techniques. Finally, future developments,
such as new sequences, new contrast agents, the role of surface coils and MR-guided biopsy, are considered. Also, the preferred
radiological approach is discussed. 相似文献
952.
P. Wunderbaldinger W. Schima K. Turetschek T. H. Helbich A. A. Bankier C. J. Herold 《European radiology》1999,9(6):1170-1182
Global exchange of information is one of the major sources of scientific progress in medicine. For management of the rapidly
growing body of medical information, computers and their applications have become an indispensable scientific tool. Approximately
36 million computer users are part of a worldwide network called the Internet or “information highway” and have created a
new infrastructure to promote rapid and efficient access to medical, and thus also to radiological, information. With the
establishment of the World Wide Web (WWW) by a consortium of computer users who used a standardized, nonproprietary syntax
termed HyperText Markup Language (HTML) for composing documents, it has become possible to provide interactive multimedia
presentations to a wide audience. The extensive use of images in radiology makes education, worldwide consultation (review)
and scientific presentation via the Internet a major beneficiary of this technical development. This is possible, since both
information (text) as well as medical images can be transported via the Internet. Presently, the Internet offers an extensive
database for radiologists. Since many radiologists and physicians have to be considered “Internet novices” and, hence, cannot
yet avail themselves of the broad spectrum of the Internet, the aim of this article is to present a general introduction to
the WWW/Internet and its applications for radiologists. All Internet sites mentioned in this article can be found at the following
Internet address: http://www.univie.ac.at/radio/radio.html (Department of Radiology, University of Vienna)
Received: 2 February 1998; Revision received: 11 June 1998; Accepted: 27 July 1998 相似文献
953.
The current study investigated the effect of erbium filtration on an anteroposterior abdominal image. The radiation dose
reductions achieveable and the costeffectiveness of this filter were also evaluated. An assessment of the radiation dose delivered
employing either the standard total filtration (3 mm Al equivalent) or 0.1 mm of erbium filtration added to the standard filtration
was undertaken on 21 patients. Image quality was assessed using the Commission of European Communities (CEC) criteria. Significant
reductions of 64.6 % in entrance surface (p = 0.0001) and 23.4 % in effective dose (p = 0.0099) were recorded with erbium
filtration. Image quality was maintained and the cost per manSievert saved was £ 128. More widespread use of this dose reducing
filter is advocated.
Received: 7 August 1998; Revised: 19 February 1999; Accepted: 19 April 1999 相似文献
954.
Benign and malignant hepatocellular tumors: evaluation of tumoral enhancement after mangafodipir trisodium injection on MR imaging 总被引:2,自引:0,他引:2
Coffin CM Diche T Mahfouz A Alexandre M Caseiro-Alves F Rahmouni A Vasile N Mathieu D 《European radiology》1999,9(3):444-449
The aim of this work was to study the ability of mangafodipir trisodium (Mn-DPDP)-enhanced MR imaging in differentiating
malignant from benign hepatocellular tumors. Eleven patients with pathologically proved hepatocellular carcinomas, six with
focal nodular hyperplasias, and one with a single hepatocellular adenoma were examined by spin-echo and gradient-echo T1-weighted
sequences before, 1 h after, and 24 h after intravenous injection of Mn-DPDP (5 μmol/kg). Quantitative analysis including
enhancement and lesion-to-liver contrast-to-noise ratio, and qualitative analysis including the presence of a central area
and a capsule were done on pre- and post-Mn-DPDP-enhanced images. Enhancement was observed in all the tumors with significant
improvement (p < 0.05) in contrast-to-noise ratio 1 h after, and 24 h after intravenous injection of Mn-DPDP. There were no significant
differences in the mean enhancement and the mean contrast-to-noise ratio (CNR) between benign and malignant tumors. No enhancement
was seen within internal areas observed in 7 hepatocellular carcinomas, and in 5 focal nodular hyperplasias, and within capsules
which were observed in 9 hepatocellular carcinomas. In our study, Mn-DPDP increased CNR of both benign and malignant tumors
but did not enable differentiation between benign and malignant tumors of hepatocellular nature.
Received: 7 October 1997; Revision received: 25 February 1998; Accepted: 10 July 1998 相似文献
955.
MR contribution in surgery of epilepsy 总被引:2,自引:0,他引:2
The contribution of MR imaging in patients with drug-resistant epilepsy considered for surgical therapy is discussed. In
this review we focus on: (a) focal abnormalities (mesial temporal sclerosis, focal migration disorders, hamartomatous lesions
and low-grade tumours, phakomatosis and vascular malformations) associated with therapy-resistant partial epilepsy, requiring
resective surgery; (b) abnormalities leading to generalized seizures that require more drastic surgical procedures, such as
callosotomy and functional hemispherectomy; and (c) localisation of implanted depth-electrodes.
Received: 6 April 1998; Revision received: 2 June 1998; Accepted: 3 June 1998 相似文献
956.
This review presents the options and limitations of MRI in non-vascular diseases of the mediastinum and the chest wall. In
numerous thoracic pathologies, MRI is a useful supplement to spiral CT. This imaging procedure also allows a contrast-media-free
differentiation of solid tumors and vascular lesions (e. g., aortic aneurysms). The advantages of MRI over CT are particularly
useful when multiplanar tumor imaging is required prior to surgery to establish the exact spatial relationship between tumor
and the other mediastinal structures. Primary indications for MRI in diseases of the mediastinum and chest wall are therefore:
(a) tumors of the posterior mediastinum for determining their position in relation to the neural foramina and the spinal canal;
(b) chest wall tumors; (c) preoperative multiplanar imaging of primary mediastinal tumors; and (d) contraindications against
CT exams with iodine contrast media. 相似文献
957.
Imaging breasts with silicone implants 总被引:5,自引:0,他引:5
Over the last two decades, the use of breast implants both for breast augmentation and for breast reconstruction following
mastectomy has increased substantially. It is estimated that around two million women have undergone breast augmentation,
while hundreds of thousands have had breast reconstruction surgery. Different types of material have been used for breast
implants, but silicone gel implants have been the dominating implant type. Many implants can lead to complications, such as
hardening and rupture, and may therefore need in vivo evaluation by imaging, particularly if they lead to clinical symptoms.
They can also pose problems in the assessment of surrounding breast tissue by conventional mammography. In this respect, imaging
modalities such as ultrasound, computed tomography and magnetic resonance imaging offer greater possibilities to assess a
failing implant, as well as surrounding breast tissue. Several factors, mainly of a psychological nature, lead to requests
for breast implants. In this review article, only the imaging aspects of breasts with silicone gel implants will be dealt
with. Each modality is concisely presented with its possibilities and limitations.
Received: 5 February 1998; Revision received: 18 May 1998; Accepted: 25 May 1998 相似文献
958.
CT of blunt trauma of the pancreas in adults 总被引:18,自引:0,他引:18
In order to describe the CT findings in pancreatic injury and to evaluate the sensitivity of this technique, we performed
a retrospective study. During a 5-year period (1993–1997), eight patients (five males and three females; age range 10–47 years)
were investigated with CT. Endoscopicretrograde cholangiopancreatography (ERCP) was obtained in two patients, pre- and intra-operatively,
respectively. Among the standard laboratory tests obtained at admission, the value of serum amylase was reviewed. The imaging
findings, especially those obtained with CT, were correlated with the surgical findings, when available (in seven of eight
patients). At admission, diagnosis of pancreatic injury was missed at CT in three of eight patients (37.5 %); thus, the sensitivity
of CT for pancreatic injury was 62.5 %. ERCP showed rupture of the pancreatic duct in the two cases in which it was performed.
Serum amylase was elevated at admission in four of eight patients, resulting in a sensitivity of 50 %. After surgery, an enterocutaneous
fistula developed in one case, and was managed conservatively. One patient died from brain injury. Proper implementation of
the CT technique and accurate film reading is mandatory to establish the diagnosis of pancreatic contusion. No correlation
between CT features and type of outcome of surgical management could be established. On retrospective review of the CT examinations,
it appeared that two of the three false-negative results could have been avoided. Therefore, proper CT technique and accurate
film reading are mandatory in establishing the diagnosis of pancreatic injury.
Received: 10 June 1998; Revision received: 26 October 1998; Accepted: 30 October 1998 相似文献
959.
Internal biliary fistulas (IBF) are seen rarely. Because the symptoms and signs of IBF are not specific and the diagnosis
is not suspected, these patients are commonly investigated with plain abdominal films (PAF), ultrasonography (US), upper gastrointestinal
series (UGIS), barium enema (BE), and computed tomography (CT), but not always with endoscopic retrograde cholangiopancreatography
(ERCP). The purposes of this article are (a) to attract attention of radiologists to presumptive findings of IBF, so as not
to misdiagnose this unsuspected and rare disease, and (b) review of the literature while presenting radiologic features of
our cases. Five cases of IBFs in which extrahepatic biliary tree communicating with duodenum (four cases) and colon (one case)
are reported. Diagnostic work-up of cases were done by PAF, US, UGIS, BE, and CT. Aerobilia, which cannot be explained using
other means, ectopic gallstone and small bowel dilatation, nonvisualization of the gallbladder despite no history of cholecystectomy,
and thick-walled shrunken gallbladder adherent to neighboring organs were suggestive findings of IBF in our study. Knowledge
of imaging findings suggestive of IBF and a high index of suspicion increase the diagnostic rate of IBFs.
Received: 4 June 1998; Revision received: 28 July 1998; Accepted: 14 October 1998 相似文献
960.
Follow-up of two hepatic angiolipomas in a patient without evidence of tuberous sclerosis is reported. Initially, the lesions
presented as homogenously enhancing masses, which were nearly isodense to normal liver tissue on plain CT scans. Focal nodular
hyperplasia was assumed. One year later, fat was detected in the growing tumors and percutaneous core biopsy revealed hepatic
angiolipomas. Natural history of these rare lesions is unknown, and this is to the best of our knowledge the first observation
of fatty metamorphosis in such a benign, mesenchymal hepatic neoplasm.
Received: 8 October 1997; Revision received: 19 March 1998; Accepted: 11 May 1998 相似文献