Biomedical subjects

T Steinmüller

Publications and source records attributed to T Steinmüller.

At least 19 recordsLinked to original sources

PubMed2005

No influence of immunosuppression on insulin sensitivity and beta-cell function in living donor liver transplantation.

In liver transplantation alterations of glucose metabolism are common but not well understood. Influence of immunosuppression is widely presumed but has not proven until now. Using a frequently sampled intravenous glucose tolerance test with a minimal modeling technique of glucose disappearance we analyzed insulin sensitivity (SI) and beta-cell function (first and second phase of pancreatic beta-cell secretion, Phi 1 and Phi 2) in living donor liver transplantation of the right lobe. Initial immunosuppression in recipients was done with tacrolimus, prednisolone, and basiliximab induction. Donors and recipients were investigated before and 10 days, 6 months, and 1 year after operation. Normal SI of controls (donors before operation) decreased markedly 10 days after right lobectomy to SI 2.22 +/- 0.35 x 10(-4) min(-1) x microU/mL (P < .001); Phi 2 was compensatory increased. All parameters normalized within 1 year. Recipients were insulin-resistant with hyperinsulinemia before transplantation. After transplantation no parameter was significantly different from donors; all normalized equally to donors over 1-year follow-up. Thus, immunosuppression in recipients has no influence on glucose metabolism because liver function itself seems to play a more pronounced role than known until now.

Adult↗

PubMed2004

[Characterization of hepatic tumors with contrast-enhanced ultrasound and digital grey-scale analysis].

PURPOSE: The characterization of different liver tumors is of therapeutic and prognostic relevance and has been the purpose of several studies. Although ultrasound offers the opportunity to detect hepatic tumors without ionizing radiation, its previous techniques did not lead toward a definitive differentiation of different tumor entities. The purpose of this study was the clinical evaluation of contrast enhanced ultrasound followed by quantitative digital analysis in patients with focal hepatic tumors. MATERIALS AND METHODS: In a prospective study, 50 patients (18 females, 32 males, age 28 to 83 years, mean age 59.4 years) with liver tumors previously detected by CT (n = 47) or MRI (n = 3) were examined by ultrasound of the upper abdomen using conventional technique and phase inversion technique after intravenous application of sulfur-based contrast enhancer SonoVue. At scheduled intervals after application of the contrast enhancer, a digital image was stored and the characteristic signal course of each lesion determined semiquantitatively. The gold standard was either resection (n = 17), percutaneous needle biopsy (n = 19) or the clinical course (n = 14). RESULTS: While the percentage of tumors correctly characterized by CT/MRI amounted to 78 %, the percentage increased from 60 % using conventional ultrasound to 86 % using contrast enhanced ultrasound including grey-scale analysis. Typical graphs were achieved for different tumor entities on digital grey-scale analysis. The optimal intervals for the differentiation of particular entities were 20 and 100 seconds after injection. CONCLUSION: Quantification of contrast enhanced ultrasound is an addition to the previous diagnostic procedure in hepatic tumors. It offers the possibility of an investigator-independent characterization of lesions and should be evaluated in further studies.

Adenoma, Liver Cell↗

PubMed2004

Role of F18-FDG PET for monitoring of radiochemotherapy -- estimation of detectable number of tumour cells.

BACKGROUND: FDG-PET has been proven to be useful for the diagnosis of pancreatic cancer. However, no quantitative data exist concerning its sensitivity for treatment monitoring or early diagnosis. CASE REPORT: We report on a 61-year-old patient with locally advanced cancer of the pancreas head who received sequential radiochemotherapy including gemcitabine and 5-FU/FA. Under this regimen, MR and CT showed a partial remission with a residual mass which seemed to allow surgical treatment for this patient. A pre-operative FDG-PETScan displayed a count rate close to the detection limit of vital residual tumour. An R0 resection was performed successfully. However, histopathology revealed residual tumour at the core of the resected mass that had gone undetected by all imaging modalities. CONCLUSION: The number of vital tumour cells within this specimen was estimated to be 10(6)-10(7). The detection threshold for FDG-PET in pancreatic carcinoma appears to be within this range.

Cell Count↗

PubMed2003

Diagnosis of neuroendocrine tumours by retrospective image fusion: is there a benefit?

This study evaluated the use of image fusion in the preoperative staging of neuroendocrine tumors (NET) of the pancreas and the gastrointestinal tract (GIT). Thirty-eight patients suffering from a metastasized NET with location of the primary in the pancreas ( n=15) or the GIT ( n=23) were examined by somatostatin receptor scintigraphy (SRS) and computed tomography (CT). Consecutive image registration and fusion were performed using custom-built software integrated in AVS/Express (Advanced Visual Systems, Waltham, MA, USA). Registration was performed by a voxel-based algorithm based on normalized mutual information. Image fusion was feasible in 36/38 patients. A total of 87 foci were assigned to anatomical regions (e.g. gut, pancreas, liver, lymph node or others) by two independent observers in both SRS and SRS/CT fusion images. The assignments used a binary ranking system (1="definite", 0="not definite"). These results were then retrospectively compared to the classification of the foci, based on postoperative histology or clinical follow-up. Imaging by SRS allowed a definite anatomical assignment in 57% (50/87) and 61% (53/87) of all lesions in the case of observers A and B, respectively. Image fusion improved the topographic assignment to 91% (79/87) and to 93% (81/87). The number classified as "definite" by both observers increased from 54% (47/87) to 86% (77/87). The increase in definite assignments was highly significant for both observers ( P<0.0001 for each). In the case of foci classified as liver metastases, image fusion allowed improved assignment to the corresponding liver segment from 45% (18/40) to 98% (39/40) and from 58% (23/40) to 100% (40/40) by observers A and B, respectively. Furthermore, the improved assignment of foci classified as lesions by image fusion was relevant for therapy in 7/36 patients (19%). Therefore, the image fusion technique presented herein appears to be a very useful method for clinical routine.

Adult↗

PubMed2003

Clinical extracorporeal hybrid liver support--phase I study with primary porcine liver cells.

The objective of this study was to evaluate the feasibility and safety of a hybrid liver support system with extracorporeal plasma separation and bioreactor perfusion in patients with acute liver failure (ALF) who had already fulfilled the criteria for high urgency liver transplantation (LTx). Eight patients (one male, seven female) were treated in terms of bridging to transplantation. The mean age was 36.5 yr (range 20 to 58). Etiology of liver failure was drug-related in two patients, hepatitis B infection in three patients, and unknown for three patients. The bioreactors were charged with primary liver cells from specific pathogen-free pigs. Cell viability varied between 91 and 98%. Continuous liver support treatment over a period of 8 to 46 h (mean 27.3 h) was safely performed and well-tolerated by all patients. No complications associated with the therapy were observed during the follow-up period. Thrombocytopenia was considered to be an effect of the plasma separation. Subsequently, all patients were transplanted successfully and were observed over at least 3 yr with an organ and patient survival rate of 100%. Screening of patient's sera for antibodies specific for porcine endogenous retroviruses (PERVs) showed no reactivity--either prior to application of the system, or after extracorporeal treatment. The results encourage us to continue the development of the technology, and further studies appear to be justified. The bioreactor technology has been integrated into a modular extracorporeal liver support (MELS) system, combining biologic liver support with artificial detoxification technology.

Adolescent↗

PubMed2003

Review article: liver transplantation for hepatocellular carcinoma.

Despite recent advances in techniques of in situ tumour ablation, surgical therapy remains at present the mainstay treatment for primary hepatic malignancies. After an initial endeavour in the establishment of liver transplantation as a treatment option, in particular for unresectable liver tumours, only a few indications, for example early hepatocellular carcinoma in cirrhosis, are currently agreed upon. Other indications, such as peripheral cholangiocarcinoma and hepatocellular carcinoma in noncirrhotics have largely been abandoned or are still under debate, as is the case with fibrolamellar carcinoma. The selection of patients suffering from hepatocellular carcinoma in cirrhosis for liver transplantation is still based on tumour size and node number, because the current state of diagnostic imaging fails to reliably predict the most important prognostic parameter: vascular infiltration. Other selection criteria are under investigation. Studies on multimodal therapy are also underway but have not yet demonstrated a clear benefit.

Carcinoma, Hepatocellular↗

PubMed2003

Complete bile duct sequestration after liver transplantation, caused by ischemic-type biliary lesions.

Ischemic-type biliary lesions (ITBLs) are the most frequent cause of nonanastomotic biliary strictures in liver grafts, affecting about 2-19 % of patients after liver transplantation. ITBL is characterized by bile duct destruction, subsequent stricture formation, and sequestration. We report here the case of a patient affected by extremely severe ITBL, with sequestration and disintegration of the entire bile duct system, in which it was possible to extract the complete biliary tree endoscopically in a single piece. Histological examination revealed that all cells of the bile duct wall had been destroyed within 3 months after liver transplantation and replaced by connective tissue. Subsequently, biliary stricture formation occurred at the hepatic hilum, as well as the adjacent large bile ducts. It may be hypothesized that cellular rejection of small bile ducts leads to the vanishing bile duct syndrome, whereas cellular rejection of large bile ducts results in ITBL. The strictures were repeatedly dilated by endoscopic means, allowing successful control of stricture formation, as well as maintenance of liver function. At the time of writing, the grafted organ and the patient had survived for more than 3 years in good health. This is the first detailed report on a sequestration of the entire bile duct system caused by ITBL, successfully treated for several years by endoscopic means.

Bile Duct Diseases↗

PubMed2003

[Accuracy of the CT-estimated weight of the right hepatic lobe prior to living related liver donation (LRLD) for predicting the intraoperatively measured weight of the graft].

PURPOSE: Due to the shortage of cadaver donors, living related liver donation (LRLD) has emerged as an alternative to cadaver donation. The expected graft weight is one of the main determinants for donor selection. This study investigates the accuracy of preoperatively performed CT-volumetry to predict the actual weight of the right liver lobe graft. MATERIALS AND METHODS: In a prospective study the weight of the right hepatic lobe was calculated by volumetric analysis based on CT in 33 patients (21 females, 12 males, mean age 42.1 years, median age 41 years) prior to living related liver donation. Graft weight was calculated as the product of CT-based graft volume and 1.00 g/ml (the approximated density of healthy liver parenchyma). The calculated weight was compared with the intraoperatively measured weight of the harvested right hepatic lobe. The difference was used to determine a correction factor for estimating the actual graft weight. RESULTS: Based on the assumption of a parenchymal density of 1.00 g/ml, the preoperatively estimated graft weight (mean 980 g +/- 168 g) deviated +33 % from the intraoperatively measured right hepatic lobe weight (mean 749 g +/- 170 g). By reducing the preoperatively predicted weight of the right hepatic lobe with a correction factor of 0.75, the actual graft weight can be calculated. CONCLUSION: Preoperative estimation of the weight of the right hepatic lobe based on CT of living related liver donors predicts the weight of the right lobe graft with sufficient accuracy by applying a single correction factor. Intraoperative fluid loss (i.e., blood, bile) from the harvested liver as well as variations in parenchymal density may contribute to the observed preoperative overestimation of the actual graft volume by CT-based volumetry.

Adult↗

PubMed2002

Right hepatic lobectomy for recurrent cholangitis after combined bile duct and right hepatic artery injury during laparoscopic cholecystectomy: a report of two cases.

BACKGROUND: Bile duct injuries in combination with major vascular injuries may cause serious morbidity and may even require liver resection in some cases. We present two case studies of patients requiring right hepatic lobectomy after bile duct and right hepatic artery injury during laparoscopic cholecystectomy. PATIENTS: Two patients sustained combined major bile duct and hepatic artery injury during laparoscopic cholecystectomy. Surgical management consisted of immediate hepaticojejunostomy with reconstruction of the artery in one patient and hepaticojejunostomy alone in the other patient. In both cases the initial postoperative course was uncomplicated. RESULTS: After 4 and 6 months both patients suffered recurrent cholangitis due to anastomotic stricture. Both developed secondary biliary cirrhosis and required right hepatic lobectomy with left hepaticojejunostomy. The patients remain well 31 months and 4.5 years after surgery. CONCLUSIONS: The outcome of bile duct reconstruction may be worse in the presence of combined biliary and vascular injuries than in patients with an intact blood supply of the bile ducts. We recommend arterial reconstruction when possible in early recognized injuries to prevent late strictures. Short-term follow-up is most important for early recognition of postoperative strictures and to avoid further complications such as secondary biliary cirrhosis.

Adult↗

PubMed2002

[Living donor liver transplantation of the right liver lobe between adults].

BACKGROUND AND OBJECTIVE: Adult living donor liver transplantation has been established in an increasing number of transplant centres during the last few years. Donor safety and risks are important criteria influencing the further development. We report our experience with 43 adult-to-adult right lobe living donor liver transplantations. METHODS: 43 patients (mean age: 49,8 +/- 16,0 years; f:m = 14:29) with end-stage liver disease received a right lobe liver graft from an adult living donor (mean age: 42,4 +/- 13,4 years; f:m = 27:16) between December 1999 and December 2001. An approval by the local ethics committee was obtained prior to the start of the programme and each donation. RESULTS: None of the donors experienced fatal or long-term complications. The rate of surgical complications in donors (biliary leakage, bleeding) was 9 %. Actuarial recipient survival was 93 % after three months and 88 % after one year. Five patients had to be re-transplanted. Thus the actuarial 1-year graft survival was 79 %. Biliary complications occurred in 14 % of all recipients. CONCLUSION: According to our experience, living donor liver transplantation of the right hepatic lobe is a safe and effective procedure. Especially for patients in acute and chronic liver failure, who otherwise would have died on the waiting list, this approach offers a life-saving option.

Adult↗

PubMed2002

[Multiorgan failure due to chronic granulomatous disease].

A 21-year-old male patient developed an acute septic clinical picture with intra-abdominal abscesses and multiorgan failure. The underlying disease was chronic granulomatous disease, an inherited disorder of granulocyte function caused by failure of intracellular superoxide production. In spite of surgical procedures and a calculated antibiotic and antimycotic therapy, the patient died within a few days from septic shock. This case report describes the typical problems of patients with a congenital immunodeficiency who grow out of the care of highly specialised pediatric-immunological departments.

Abdominal Abscess↗

PubMed2002