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W G Zoller

Publications and source records attributed to W G Zoller.

At least 37 records · Page 2Linked to original sources
PubMed1998

Role of ultrasonography for monitoring tumor necrosis after chemotherapy.

Ultrasonography for monitoring the response of malignant liver lesions to regional therapy offers several advantages. The instrument is easy to transport and can be used in intensive care units, so it is the procedure of choice within the first few days after invasive techniques, such as isolated liver perfusion, to demonstrate tumor response. Changes in size or in the sonomorphological pattern of liver lesions early after therapy indicate a therapeutic response. There are no data available on the sensitivity of ultrasonography for differentiating the necrotic and viable parts of the tumor. If information on the extent of tumor necrosis is crucial for decisions on further treatment of a patient, ultrasonography should be complemented with other techniques, such as fine-needle puncture or imaging techniques such as computed tomography, nuclear magnetic resonance, and single photon emission computed tomography. The contribution of more recent developments in ultrasonography, such as color Doppler analysis of intratumoral blood flow or three-dimensional ultrasonography, for monitoring tumor necrosis remains to be evaluated.

Drug Monitoring↗
PubMed1998

[Volumetry of circumscribed liver changes with 3-D ultrasound in comparison with 3-D computerized tomography].

The accuracy of volume measurement using three-dimensional ultrasound (3D-US) in comparison to three-dimensional computer tomography (3D-CT) was evaluated in 11 patients. The deviation of tumor volumes measured with 3D-US (ellipsoid formula) from 3D-CT was -28% to +9% and for 3D-US (planimetry reconstruction) from 3D-CT was -21% to +9%. These data show that volume measurement using 3D-US provides comparable results to 3D-CT. Clinically, 3D-US could be helpful in the follow-up of patients with non-resectable tumors or in planning liver resections by assessing the volume of liver tissue remaining after resection or by a better visualization of the topography of liver tumors and major hepatic structures.

Follow-Up Studies↗
PubMed1997

The influence of the spatial structure of focal hepatic lesions on volume measurements performed with two and three-dimensional sonography using the ellipsoid formula.

A total of 63 patients with localized hepatic lesions were examined using two and three-dimensional sonography. The tumor volumes were calculated by means of the ellipsoid formula, compared with an experimentally determined reference volume and subsequently differentiated into correct and erroneous measurements according to the WHO criteria for tumor volumes. In a second test series, an analysis of the tumor shapes was carried out using parallel projections. It could be seen that 65% of the erroneous measurements resulted from the use of the ellipsoid formula, a procedure which is used to determine the volume of hepatic lesions. In the third part of this study, it was found that findings which are difficult to measure are frequently not recognized as such by the investigator making use of two-dimensional sonography. As a consequence, the volume measurements of focal hepatic lesions in oncology patients being considered for particular therapies should preferably be carried out with the aid of planimetric measurements rather than with the use of the ellipsoid formula.

Biometry↗
PubMed1997

Medical prophylaxis of haemorrhage from oesophageal varices in patients with liver cirrhosis.

Haemorrhage from oesophageal varices is a life-threatening event in patients with liver cirrhosis. About 40-80% of patients surviving the first bleeding suffer a recurrence within 1 year. This high recurrence rate substantially contributes to the mortality in patients with liver cirrhosis. Therefore, various treatment regimens in both primary and secondary prophylaxis were studied. Most experience in medical primary prophylaxis was collected with beta-blockers, mainly propranolol. Treating patients with oesophageal varices with propranolol significantly reduces the incidence of first variceal bleeding. However, the effect on mortality is marginal, and primary prophylaxis is generally not recommended in these patients. Several studies support the hypothesis that medical prophylaxis with beta-blockers is more effective in reducing the rate of first oesophageal bleeding in patients with a high risk of haemorrhage, such as those with very large varices with red spots. A score to assess an individual patient's risk of variceal bleeding would be helpful, but until such a score has been validated, no general rule for this treatment decision can be given. In secondary prophylaxis, both beta-blockers and endoscopic therapy (sclerotherapy or ligation of the varices) are effective in lowering the rate of rebleeding. However, the effect on mortality was not significant in most studies. Several studies comparing the efficacy of medical prophylaxis and endoscopic treatment showed advantages of the endoscopic therapy with a greater reduction in recurrent bleeding episodes. However, medical prophylaxis with beta-blockers has the important advantage of being immediately effective, whereas endoscopic procedures provide the best protection against recurrent bleeding after complete obliteration of the varices. Therefore, in the first weeks and months of endoscopic therapy, additional treatment with beta-blockers may further reduce the risk of rebleeding. Only half of all studies on this topic reported a significant advantage with this combined therapy. Therefore, it seems reasonable to restrict this approach to patients with a high risk of rebleeding, such as patients with large sclerotherapy-derived oesophageal ulcers.

Adrenergic beta-Antagonists↗
PubMed1997

Gastrointestinal lymphomas in patients with AIDS.

Non-Hodgkin-lymphoma (NHL)-most frequently high grade B-cell lymphoma-occurs in 5-10% of individuals with HIV-infection. The gastrointestinal tract (GIT) is the most frequent extranodal site of the disease. The optimal therapy for HIV-related lymphoma remains a matter of controversy. In a retrospective analysis we found gastrointestinal lymphoma in ten of 306 HIV-infected patients (3.3%) with a median CD4-count of 92/microliter at time of diagnosis. Median survival for the chemotherapy treatment group was 15 months. The high incidence of gastrointestinal NHL prompted us to commence a prospective survey on diagnostic procedures, therapy and outcome of patients with HIV-infection and gastrointestinal symptoms. 93 of 341 HIV-infected patients with gastrointestinal symptoms were examined by endoscopy. In selected patients we used in addition endoscopic ultrasound (EUS) for visualization and staging before and after chemotherapy. NHL of the GIT was detected in seven of 93 endoscopically examined patients (7.5%). All patients were treated with CHOP initially. Mean survival time was ten months, mean CD4-count at diagnosis 193/microliter (range 0-417). Our results indicate that the diagnosis of gastrointestinal lymphoma should be considered in any HIV-infected patient presenting with unexplained gastrointestinal symptoms. In this group of patients NHL was detected in 7.5% of cases. The use of EUS improves the staging procedure before therapy. Treatment with CHOP resulted in relatively high remission rates and was associated with a low rate of treatment-induced myelosuppression.

Adult↗
PubMed1997

[Patient-oriented, risk-adapted tumor aftercare in patients with colorectal carcinoma].

Follow-up programs in patients with colorectal cancer have been criticized concerning their efficacy. Uniform programs for all patients as practised during the last decade did neither influence survival nor did they improve the number of secondary tumor resection for cure. Therefore we developed a follow-up program that considers patient's healthiness, status of resection in primary operative therapy and the risk of tumor recurrence depending on postoperative tumor staging. Because of these considerations we divided patients into three groups: Patients with low risk, high risk and patients treated with palliative aspects. Thus costs of follow-up programs could be reduced to more than 50%.

Aftercare↗
PubMed1996

Beta-blockers for prophylaxis of bleeding from esophageal varices in cirrhotic portal hypertension. Review of the literature.

Hemorrhage from esophageal varices is a life-threatening event in patients with liver cirrhosis. About 40% to 80% of the patients surviving the first bleeding suffer from a recurrence of variceal bleeding within one year. This high recurrence rate substantially contributes to the mortality in patients with liver cirrhosis. Therefore, various treatment regimens both in primary and secondary prophylaxis were studied. Most experience in medical primary prophylaxis was collected with beta-blockers, mainly propranolol. Treating patients with esophageal varices with propranolol significantly reduces the incidence of first variceal bleeding. However, the effect on mortality is marginal, and primary prophylaxis is generally not recommended in these patients. Several studies support the hypothesis, that medical prophylaxis with beta-blockers is more effective in reducing the rate of first esophageal bleeding in patients with a high risk of hemorrhage, such as the presence of very large varices with red spots. A score to assess the individual risk of a given patient to suffer a variceal bleeding would be helpful. As long as such a score is not validated, no general rule for this treatment decision can be given. In secondary prophylaxis, both administration of beta-blockers and endoscopic therapy (sclerotherapy or ligation of the varices) are effective in significantly lowering the rate of re-bleeding. However, the effect on mortality was not significant in most studies. Several studies comparing the efficacy of medical prophylaxis and endoscopic treatment showed advantages of the endoscopic therapy with a greater reduction in recurrent bleeding episodes. However, medical prophylaxis with beta-blockers has the important advantage of being immediately effective whereas endoscopic procedures provide the best protection against recurrent bleeding after complete obliteration of the varices. Therefore, in the first weeks and months of endoscopic therapy, the additional treatment with beta-blockers may further reduce the risk of re-bleeding. Only half of all studies on this topic reported a significant advantage of such a combined therapy. Therefore, it seems reasonable to restrict this approach to patients with a high risk of re-bleeding such as patients with large sclerotherapy-derived esophageal ulcers.

Adrenergic beta-Antagonists↗
PubMed1996

[Reversible esophageal dysfunction as a side effect of levodopa].

We are reporting the case of a 94-year-old male patient with a 10-year history of Parkinson's disease, who was admitted to our hospital with acute obstruction of esophageal passage. Esophageal obstruction was refractory to endoscopic intervention. However, discontinuation of the pre-existing levodopa medication led to its resolution within hours. While dysphagia is commonly encountered in patients with Parkinson's disease, the observed succession of drug discontinuation and resolution of obstruction in this case suggests an as yet rarely described side effect of levodopa. This potential side effect should be included in the differential diagnosis of dysphagia in Parkinson's disease, especially in the case of older patients, who may exhibit an increased rate of intestinal absorption of levodopa.

Aged↗
PubMed1996

[Value of ultrasound in diagnosis of acute appendicitis].

Acute appendicitis is one of the most frequent causes of an acute abdomen. The clinical diagnosis is based on the case history and the physical examination which plays a major role in clinical diagnosis. However, in some cases the typical clinical symptoms are equivocal or misleading. Without using the opportunities of diagnostic imaging the accuracy of preoperative appendix diagnosis ranged between 70 and 78%. Consequently the rate of unnecessary laporotomies ranged between 22 and 28%. Since 1986, 13 studies including more than 5,000 patients have been published showing a sensitivity of 85% and a specificity of 96% if the sonographic examination was performed by an experienced examiner. The rate of negative laparotomies could be decreased to 7%, and possible differential diagnoses could be either confirmed or ruled out by using ultrasound technique. Based on the current literature, real-time sonography plays a major part in the diagnosis of acute appendicitis.

Abdomen, Acute↗
PubMed1996

[Antibiotic-induced prolonged cholestasis: suspected induction by ceftibuten].

We report on a 43-year-old female diabetic patient who was treated with ceftibuten because of Pseudomonas aeruginosa induced otitis externa. Thereafter she developed a prolonged seven-months-persisting irreversible cholestasis. Liver puncutre revealed a canalicular and hepatocellular cholestasis without liver cell necrosis or bile duct injury. After seven-months the patient died because of antibiotic-resistant Pseudomonas-septicemia.

Adult↗
PubMed1996

[Diagnosis and therapy of portal hypertension].

Portal hypertension, defined by a constant increase of the portal vein pressure over 5 to 10 mmHg, is usually caused by a pre-, intra- or posthepatic obstruction of the portal blood flow. Advances in ultrasound techniques like duplex or colour doppler enabled portal hypertension to be diagnosed safely in a noninvasive way. Invasive procedures for the measurement of portal pressure or blood flow are just applied for scientific and pharmacological questions. The therapy of portal hypertension concentrates on the treatment of its complications: The management of the acute variceal hemorrhage should follow a sequential regime. The treatment of the individual patient however, depends on the special experiences of the responsible doctor. In the primary and secondary prophylaxis of hemorrhage from esophageal varices the administration of portal pressure reducing agents like beta-blockers, sclerotherapy or banding of esophageal varices, represent effective strategies. Trials in the future should concentrate on the characterization of these patients, who show the best response to different prophylactic strategies. The treatment of ascites is according to a sequential procedure. Peritoneovenous shunts are usually not necessary. The transhepatic intrajugular portosystemic stent shunt offers a new therapeutic option of complications of portal hypertension. First studies show encouraging results.

Esophageal and Gastric Varices↗
PubMed1996

[Endosonography of tumors of the upper gastrointestinal tract: is routine use justified?].

Major indications of endoscopic ultrasound (EUS) are staging of carcinomas of the oesophagus, stomach, and pancreas, lymphomas of the stomach and the diagnosis of submucosal tumors. Based on a meta-analysis, the accuracy of EUS is 84% in the T-stage of oesophagus carcinoma (1154 patients) and 77% (1035) in the N-stage, and of stomach carcinoma 80% (2699) and 70% (1207), respectively. Drawbacks of EUS: tumor stenosis which cannot be passed by the endoscope; the inability to distinguish between benign and malignant stomach ulcera and the diagnosis of lymph nodes.

Endosonography↗