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W Schima

Publications and source records attributed to W Schima.

At least 19 recordsLinked to original sources

Selective resection of colorectal liver metastases.

AIMS: Safety of liver surgery for colorectal cancer liver metastases after neoadjuvant chemotherapy has to be re-evaluated. PATIENTS AND METHODS: Two hundred Patients were prospectively analyzed after surgery for colorectal cancer liver metastases between 2001 and 2004 at our institution. Special emphasis was given to perioperative morbidity and mortality under modern perioperative care. RESULTS: There was no in-hospital mortality and the perioperative morbidity was 10% (20/200). Four patients had to be reoperated due to bile leak or intraabdominal abscess. The remainder either had infectious complications or pleural effusion and/or ascites requiring tapping. Variables strongly associated with decreased survival were T, N, G and UICC (International Union against cancer) classification of the primary, hepatic lesions>5 cm and elevated tumour markers. Short disease free interval and neoadjuvant chemotherapy without response predicted impaired recurrence free survival (RFS). Multivariate analysis revealed lymph node status and differentiation of the primary, presence of extrahepatic tumour and gender as factors associated with decreased survival. Administration of neoadjuvant chemotherapy was not associated with higher postoperative morbidity or prolonged hospital stay. CONCLUSIONS: Modern dissection techniques and improved perioperative care contributed to a very low rate of surgery-related morbidity (10%) and a zero percent mortality which was also observed in patients pretreated with neoadjuvant chemotherapy prior to resection. Liver resection in experienced hands has become a safe part in the potentially curative attempt of treating patients with metastatic colorectal cancer.

Adult↗

[Pancreas. Part I: congenital changes, acute and chronic pancreatitis].

The pancreas develops from ventral and the dorsal buds, which undergo fusion. Failure to fuse results in pancreas divisum, which is defined by separate pancreatic ductal systems draining into the duodenum. Risk of developing pancreatitis is increased in pancreas divisum because of insufficient drainage. MR cholangiopancreatography (MRCP) is the technique of choice for detecting pancreas divisum non-invasively. Annular pancreas is the result of incomplete rotation of the pancreatic bud around the duodenum with the persistence of parenchyma or a fibrous band encircling (and sometimes stenosing) the duodenum. Acute pancreatitis is usually caused by bile duct stones or alcohol abuse. The Atlanta classification differentiates between mild acute and severe acute pancreatitis associated with organ failure and/or local complications such as necrosis, abscess or pseudocyst. Contrast-enhanced multi-detector row CT is the method of choice to assess the extent of disease. Balthazar et al.'s CT severity index assesses the risk of mortality and morbidity. In acute pancreatitis, the role of MRCP is mainly limited to finding bile duct stones in patients with suspected biliary pancreatitis. Chronic pancreatitis results in relentless and irreversible loss of exocrine (and sometimes endocrine) function of the pancreas. MDCT even shows subtle calcifications. MRCP is the method of choice for non-invasive assessment of the duct. Inflammatory pseudotumor in chronic pancreatitis and groove pancreatitis are difficult to differentiate from pancreatic cancer. In these cases, multiple imaging methods such as MDCT, MRI and endosonography including biopsy may be used to make a diagnosis.

Acute Disease↗

[Pancreas. Part II: Tumors].

Adenocarcinoma is the most common malignant pancreatic tumor, affecting the head in 60-70% of cases. By the time of diagnosis, approximately 80% of tumors are unresectable. Helical CT is very effective in detection and staging of adenocarcinoma, with a sensitivity of 76-92% for detection and an accuracy of 80-90% for staging, but it has limitations in the detection of small cancers (< or =2 cm). Multidetector CT (MDCT) has brought substantial improvements with its inherent 3D imaging capability. Mangafodipir-enhanced MRI is a problem-solving tool in the depiction of small cancers following an equivocal CT imaging result. Gadolinium-enhanced 3D gradient-echo MRI is helpful in the assessment of vascular invasion of cancer and in determining the etiology of cystic lesions. Serous cystadenoma is benign, has a lobulated contour and contains innumerable small cysts of 0.1-2 cm in diameter. Mucinous cystic neoplasms are unilocular or multilocular (fewer than six cysts), and the cyst diameter exceeds 2 cm. The presence of solid nodular components should alert the radiologist to suspect cystadenocarcinoma. Neuroendocrine tumors are mostly hypervascular. Diagnosis of insulinoma is a challenge: they are <2 cm in 90% of cases and mostly hypervascular at CT or MRI. A combination of contrast-enhanced MDCT, MRI, endosonography, and/or somatostatin receptor scintigraphy is used to detect these small tumors. This review summarizes the imaging features of the most common pancreatic tumors and discusses the limitations of CT, MRI and endosonography.

Adenocarcinoma↗

[Anatomy and variants of hepatic segments, vessels, and bile ducts].

Knowledge of normal liver anatomy and its variants is indispensable for the radiologist. Accurate assessment of anomalies of the arterial, portal (venous), and biliary system and of liver segments using computed tomography is necessary for consultation with the surgeon and deciding on the therapeutic strategy. The multidetector CT is the most important tool for preoperative evaluation. Alternatively, MRI can be used with special regard to the biliary system (MRCP). This article reviews the most important variants of the liver detected with imaging modalities and their clinical relevance.

Bile Ducts, Intrahepatic↗

[Multidetector computed tomography of the liver].

Multidetector-row CT (MDCT) scanners have dramatically improved liver imaging. With the newest generation of 40-64 row scanners, true isotropic imaging with a z-axis resolution of 0.3-0.6 mm has become possible. Acquisition time for the scan has been shortened to a few seconds. To fully exploit the advantages of MDCT scanners in liver imaging, the examination protocols have to be optimized with regard to contrast material flow rate, scan delay, and the number of scans performed. The possible advantages of double arterial phase scans in the detection of HCC are discussed. The clinical value of 3D reconstructions, such as multiplanar reconstructions and curved planar reconstructions, for assessment of the vascular and biliary duct infiltration is demonstrated. Optimized MDCT imaging improves detection and characterization of focal liver lesions.

Bile Duct Neoplasms↗

[MRT of the liver. Clinical significance of nonspecific and liver-specific MRT contrast agents].

The liver is a common site for various benign and malignant focal lesions. The initial modality for assessing liver lesions is ultrasound or CT. MRI with its superior soft tissue contrast offers multiple advantages over other imaging modalities. Contrast agents have been developed that increase the detection rate and provide more specific information in comparison to unenhanced techniques. In the mean time three classes are available for MR imaging of the liver: extracellular gadolinium chelates, hepatobiliary and reticulo-endothelia, superparamagnetic agents. We describe in this review the most common focal lesions, their diagnostic possibilities, and the imaging protocols. Clinical use of these contrast agents facilitates detection and differential diagnosis of focal liver lesions that may help to avoid invasive procedures such as biopsy for lesion characterization.

Chelating Agents↗

Iodine-123-vascular endothelial growth factor-165 (123I-VEGF165). Biodistribution, safety and radiation dosimetry in patients with pancreatic carcinoma.

AIM: Imaging with radiolabelled vascular endothelial growth factor (VEGF) has been developed for the localisation and diagnosis of a variety of human solid tumors including gastrointestinal tumors. METHODS: In this study we investigated the biodistribution, safety and absorbed dose of iodine-123 radiolabelled VEGF(165) ((123)I-VEGF(165)) in 9 patients with pancreatic carcinoma. Following intravenous administration of (123)I-VEGF(165) (189+/-17 MBq; <130 pmole (<5 microg) VEGF(165) per patient), sequential images were recorded during the initial 30 min PI. Serial whole-body images were acquired in anterior and posterior views at various time points. All patients underwent single-photon emission tomography (SPET) imaging. Dosimetry calculations were performed on the basis of gamma camera data. Estimates of radiation absorbed dose were calculated using the MIRDOSE 3 program. RESULTS: The highest absorbed organ doses were found to be thyroid (0.058+/-0.004 mGy/MBq), spleen (0.046+/- 0.017 mGy/MBq), urinary bladder (0.04+/-0.02 mGy/MBq), lungs (0.034+/-0.009 mGy/MBq) and kidneys (0.033+/-0.005 mGy/MBq). The effective dose was estimated to be 0.017+/-0.002 mSv/MBq. A majority of primary pancreatic tumors and their metastases were visualized by (123)I-VEGF(165) scan. CONCLUSION: In vitro binding results confirmed specific binding of (123)I-VEGF(165) to pancreatic tumor cells and tissues. (123)I-VEGF(165) shows favorable dosimetry and is a safe radiopharmaceutical that may be of potential value for the imaging of VEGF receptor status in vivo.

Adenocarcinoma↗

Reversibility of cirrhotic regenerative liver nodules upon NTBC treatment in a child with tyrosinaemia type I.

UNLABELLED: In a male patient with hereditary tyrosinaemia type I (HTI), NTBC [2-(2-nitro-4-trifluoro-methylbenzoyl)-1,3-cyclohexandion] treatment and a diet low in phenylalanine and tyrosine were started at the age of 4 wk. At the recommended average dosage (1 mg kg(-1)), liver failure improved transiently. After 4 mo of treatment, with increased body weight, the dose had decreased to 0.7 mg kg(-1), and diffuse cirrhotic changes in liver parenchyma and multiple nodules were visualized by ultrasonography. Multiple nodules in the liver parenchyma were differentiated from hepatocellular carcinoma by magnetic resonance imaging (MRI) using mangafodipir trisodium as a paramagnetic liver-specific contrast agent. Augmentation of NTBC dosage resulted in a decrease in serum alpha-fetoprotein levels and in significant regression of liver nodules on MRI. CONCLUSION: In HTI patients with a poor response to NTBC treatment and/or development of cirrhotic changes of liver parenchyma, augmentation of the recommended NTBC dosage may result in significant improvement of symptoms.

Cyclohexanones↗

Enteroclysis in adult celiac disease: diagnostic value of specific radiographic features.

The purpose of this study was to compare the diagnostic accuracy of various radiographic findings at enteroclysis in adult patients with untreated celiac disease. Twenty-seven adult patients underwent enteroclysis because of unspecific intestinal symptoms before definitive biopsy proof of celiac disease. Enteroclysis of 123 subjects with similar clinical presentation, including abdominal pain, diarrhea, occult intestinal bleeding, and weight loss, who had a definitive diagnosis other than celiac disease, served as controls. The radiographic features previously described in the literature as indicative of adult celiac disease (i.e., fold thickening, decrease of jejunal folds, increase of ileal folds, small bowel dilatation, flocculation) were evaluated in blinded fashion in all studies and the subjective likelihood of diagnosis of celiac disease was assessed. Assessing every finding separately, each feature proved to have a high specificity (78-100%) but low sensitivity (19-59%) for celiac disease. Reversal of jejunoileal fold pattern was the single best feature (specificity 100%, 95% CI 97-100%; sensitivity 59%, 95% CI 40-78%); however, combination of criteria enables establishment of the diagnosis of celiac disease quite accurately (specificity 100%, 95% CI 98-100%; sensitivity 78%, 95% CI 58-91%). Reversal of jejunoileal fold pattern as a single finding as well as combination at least three of the following features, i.e., fold thickening, decrease of jejunal folds ("colonization"), increase of ileal folds ("jejunization"), dilatation, and flocculation, make enteroclysis an accurate tool for diagnosis of celiac disease in adult patients with suspected intestinal disease.

Adult↗

[Certification according to ISO 9001--waste of time or necessity?].

Quality management (QM) systems are widely established management tools in the industry and business world today. In the health care sector, the need for quality, the implementation of quality management systems and economic orientation of the hospital management are strongly encouraged. Centers of excellence are created to offer special medical services of the highest possible quality. Furthermore, there is a worldwide tendency to establish standards in clinical medical settings, in teaching profession and medical science. These trends make the implementation of a quality management system in health care system highly desirable. The present manuscript reviews the fundamental principles and concepts and the aims of internationally accepted QM systems. It focuses on the ISO-9000 certificates and the European Foundation of Quality Management (EFQM) model. The advantages and disadvantages are discussed. The resources necessary for installation of a QM system and the different phases of implementation are reported. According to the experience of several groups, QM systems can be reliably used in a radiology department and lead to continuous improvement of the quality of services.

Austria↗

[Intravenous administration of iodinated, non-ionic, low or isoosmolar contrast media: safety aspects].

It is the purpose of this review to provide information about the safe use of intravenously administered, iodinated, non-ionic, low or isoosmolar contrast media for radiological examinations, how to avoid adverse events, and how to react professionally in case of an anaphylactic reaction. Methods of prophylaxis and therapy for anaphylactic and chemotoxic effects of contrast media administration as well as absolute and relative contraindications are discussed. Medico-legal considerations of contrast agent administration, informed consent of patients, and methods of risk management for undesired contrast media reactions are considered in this article. Establishment of adminstration standards for contrast media is of tremendous importance to standardize radiological procedures. This basic radiological documentation is part of the institutional and individual legal safety management.

Anaphylaxis↗

[Organ specific MRI contrast media in general practice].

Conventional MR imaging with non-specific gadolinium contrast agents is useful in the detection and staging of malignancies. With the development of organ-specific MR contrast agents, MR imaging is assuming an even larger role in body imaging. Two different classes of liver-specific agents, hepato-biliary agents targeted to the hepatocytes, and reticulo-endothelial agents (or Kupffer cell agents) targeted to the reticuloendothelial system in the liver and spleen, have been developed. MRI with liver-specific contrast agents is superior to helical CT for detection of liver metastases. Mangafodipir, which was originally developed as a liver-specific agent, has been shown to accumulate in the pancreas as well. Recent studies have revealed that mangafodipir-enhanced MRI is at least equal to spiral CT in the staging of pancreatic cancer and may be superior to CT in the detection of small cancers. Blood-pool contrast agents with a long blood half-life, such as ultrasmall iron oxide particles (USPIO), have been developed for MR angiography. After the clearance from the vascular system, USPIO are taken up by phagocytes and accumulate in normal lymph, but not in metastatic nodes. This effect can be exploited to increase the accuracy of MRI in lymph node staging of cancer of head-neck, lung or pelvis. In conclusion, various organ-specific MR contrast agents with a wide range of clinical applications have been developed. Future studies will demonstrate the role of contrast-enhanced MRI in comparison with multi-detector array CT.

Contrast Media↗

Adrenal hemorrhage after orthotopic liver transplantation: MR appearance.

The purpose of this paper is to describe the MR imaging findings of right adrenal hemorrhage after orthotopic liver transplantation. Twenty-seven orthotopic liver transplantation patients underwent MR studies of the liver and/or biliary system. Patients were referred to MR examination because of suspected biliary complications ( n=22) or for evaluation of mass lesions ( n=5). The standard MR protocol included T1-weighted spin-echo (SE) or gradient-recalled echo (GRE) images and T2-weighted turbo SE (TSE) images with fat suppression. In addition, cholangiography pulse sequences and/or contrast-enhanced T1-weighted images were obtained according to specific indications. In 2 patients a right adrenal mass was detected at MR imaging. Three to 4 weeks after transplantation, the lesions were markedly hyperintense on T2-weighted images and showed a hypointense capsule. Follow-up MR examinations revealed a slight decrease in size and a change in morphology. Computed tomography examinations of these 2 patients, obtained 10 weeks after transplantation, showed resolution of the hemorrhage and transformation into a cystic lesion in one case and a complete resolution of the hemorrhage and a normal right adrenal gland in the other case. Adrenal hemorrhage after liver transplantation shows typical MR features and should not be mistaken for an adrenal tumor or a postoperative abscess.

Adrenal Gland Diseases↗

Evaluation of perianal sepsis: comparison of anal endosonography and magnetic resonance imaging.

The purpose of this study was to compare prospectively the diagnostic yield of anal endosonography (AES) and magnetic resonance imaging (MRI) in the assessment of perianal fistulae and abscesses. There were 39 patients (14 men, 25 women; mean age, 40 years) who underwent AES, performed with a 10-MHz rotating endoanal probe and MRI at 1.0 T (axial and coronal T2-weighted turbo spin-echo (TSE) and turbo-STIR sequences). Fistulae were classified as subcutaneous, intersphincteric, transsphincteric, high (i.e., high extrasphincteric or suprasphincteric), rectovaginal, and horseshoe and were compared with the surgical findings in all patients. Overall, 58 fistulae (subcutaneous, N = 7; intersphincteric, N = 9; transsphincteric, N = 16; high, N = 17; rectovaginal, N = 5; and horseshoe, N = 4) were detected at surgery. MRI showed a sensitivity of 84% and AES of 60% (P <.05). False-positive diagnoses were made in 6 patients (15%) with MRI and in 15 patients (26%) with AES, for a specificity of 68% and 21%, respectively (P <.05). Our findings show that MRI is superior to AES in the assessment of fistula-in-ano before major surgery. AES should be used only for orientation before minor procedures, such as incision or drainage of subcutaneous fistulae.

Adult↗

Peripancreatic fat necrosis mimicking pancreatic cancer.

A case of peripancreatic fat necrosis, after an episode of acute pancreatitis, which mimicked pancreatic cancer with lymph node metastases, is presented. We describe the imaging findings with helical CT scanning and with unenhanced and mangafodipir-enhanced MR imaging, with special emphasis on the differential diagnoses.

Adult↗

Displacement of coils into the lung during embolotherapy: clinical importance and follow-up with helical CT.

RATIONALE AND OBJECTIVES: The authors performed this study to evaluate the clinical importance and computed tomographic (CT) appearance of coils displaced into the lung during embolotherapy. MATERIALS AND METHODS: The authors retrospectively studied clinical charts and serial chest images from 25 consecutive patients after coil embolization. Chest radiography was performed in all patients, whereas helical chest CT was performed only in patients in whom dislocated coils were visible on chest radiographs. Coils were applied for the treatment of peripheral arteriovenous (AV) malformations and fistulas (n = 9), renal AV malformations or fistulas (n = 8), and primary or secondary tumors (n = 8). Clinical charts were analyzed for short- and long-term symptoms; chest radiographs and CT scans were reviewed for signs indicative of pulmonary infarction. RESULTS: None of the patients had clinical symptoms suggestive of pulmonary infarction. In two of the 25 patients (8%), displaced coils were seen in the pulmonary vasculature at chest radiography; these patients had been treated for renal AV fistula and peripheral AV fistula, respectively. One patient had two coils in the left hemithorax (upper and lower lobe), and the other patient had two coils in the right hemithorax (middle lobe). Neither of the patients had abnormalities suggestive of pulmonary infarction at helical CT. CONCLUSION: Chest radiography can help confirm the presence of coils displaced to the pulmonary vasculature during embolotherapy. Helical CT can also help rule out the presence of coil-associated pulmonary infarction.

Adolescent↗

MRI contrast agents for evaluating focal hepatic lesions.

Contrast-enhanced magnetic resonance imaging (MRI) has become an important tool in the detection and characterization of focal hepatic lesions especially when other investigations such as ultrasound (US) and computed tomography (CT) are inconclusive. The purpose of this pictorial review is to briefly summarize the properties of various MRI contrast agents used in hepatic imaging and to highlight their role in evaluation of focal hepatic lesions.

Contrast Media↗