Biomedical subjects

U T Hopt

Publications and source records attributed to U T Hopt.

At least 37 records · Page 2Linked to original sources

PubMed2005

[German Artificial Sphincter System--GASSII: first in vivo evaluation of a novel and highly integrated sphincter prosthesis for therapy of major fecale incontinence].

The German Artificial Sphincter System GASS consists of a support ring which includes a fluid reservoir on the outer side and an occlusive cuff on the inner side. The cuffs are designed as polyurethane hollow bodies with a pre-determined inflation volume and are connected to an integrated piezo micropump/valve unit. To evaluate the threshold of continence, the GASS was placed around the anorectal junction via a perineal approach in one mini pig. The novel cuff design reduces the occlusion pressure and allows low compression volumes. Low operating pressures indicate a minor risk of ischemia injury of the bowel. The operation time is estimated at about 6 days with no recharging of the battery. The novel remote controlled GASS is a highly integrated prosthesis for placement around the anal canal or lower rectum and is effective in restoring continence for liquids and solids in vitro and in vivo.

Anal Canal↗

PubMed2004

Electrodynamic smooth muscle sphincter: development and biomechanical evaluation of a novel porcine artificial smooth muscle sphincter in a new in vitro stoma simulator.

AIM: Many authors have suggested that the activity of the enteric inhibitory nerves is important in regulating normal gastrointestinal motility and inducing smooth muscle relaxation. Hitherto, no experimental or clinical models exist that transfer these physiological aspects to creating an autologous artificial sphincter for the treatment of major incontinence. Therefore, this study was performed to determine the contractile and relaxant capacity of gastrointestinal muscle types and to investigate the efficiency of a novel smooth muscle sphincter, based on the non-adrenergic, non-cholinergic (NANC) receptive relaxation under electrical field stimulation (EFS). METHODS: For the first step, the isometric tension from isolated circular porcine fundus and colon muscle strips was recorded during pharmacological stimulation (TTX, L-NNA and atropine) and EFS. As a result, a continent electrodynamic smooth muscle sphincter (ESMS) was created by wrapping a fundus muscle flap around an isolated segment of porcine distal colon. The EFS of the free nerve fibers of the flap was realized using a circular platinum wire electrode. Parameters such as threshold of continence, intra/preluminal pressure and fluid passage were analyzed in a newly designed in vitro stoma simulator. RESULTS: Electrical field stimulation produced a maximal and voltage-dependent fundus relaxation to --12.4 mN/mm(2) (frequency of 40 Hz, pulse duration, train duration and voltage of 5 ms, 1 s and 60 mA respectively), which were abolished by N-nitro-L -arginine (L-NNA; 10(-4) M) in a dose-dependent manner, confirming that relaxant responses were mediated by NANC nerves. The results of eight ESMS showed that circular electrical stimulation of the muscle flap caused muscle relaxation with a concomitant and effective reduction in the occlusion pressure. CONCLUSION: The NANC-induced relaxation mechanism of porcine fundus preparations could be transferred to an efficient smooth muscle sphincter with a high threshold of continence and electrically controlled defecation.

Anal Canal↗

PubMed2004

[The non-healing wound].

The most common chronic wounds are pressure ulcers, diabetic ulcers, arterial occlusive disease and venous ulcers. The therapeutic aim after appropriate diagnostic work-up is causal treatment. Pressure relief, revascularisation or compression head the list of potential measures. Apart from local factors such as infection or necrosis, systemic factors such as patient compliance, renal insufficiency and immunosuppression are of relevance. If there is a chance of healing, wound management comprises repeated debridement and wet dressings. In the presence of an infection, local antiseptic treatment is indicated. In the individual case, wound stimulation can be supported by protease inhibitors, growth factors or tissue engineering. Definitive wound closure is achieved by epithelial migration from the margins of the wound, or by plastic surgery. Regular documentation of the course and success of wound healing is mandatory. In the wound care center, surgical disciplines, diabetology, dermatology and diagnostic work-up are coordinated, and liaison with the family doctor and home care providers practiced. This wound healing concept successfully heals approximately 80% of the cases of chronic wounds in 18.8 months (mean healing duration 4.8 months).

Adult↗

PubMed2004

Solitary fibrous tumour of the liver: case report and review of the literature.

BACKGROUND: Solitary fibrous tumours (SFTs) of the liver are very rare entities. Although firstly described to be tumours of pleural origin, SFTs have been reported in various organs such as the meninges, orbit, upper respiratory tract, thyroid, peritoneum, retroperitoneum and soft tissues. Histologically, this tumour often shows alternating cellular and relatively acellular areas. The cellular areas show a wide variety of patterns, making it difficult for it to be differentiated from other mesenchymal tumours. Its immunohistochemical positivity for CD34 and vimentin is believed to be unique. Histiogenesis of SFTs, however, is not yet fully understood. They are known to be usually benign, with only few reports indicating their ability to metastasize. PATIENTS AND METHODS: We review the literature on SFTs of the liver and report on the case of a 63-year-old female patient with a large SFT of the right liver. CONCLUSIONS: Surgical resection seems to be the treatment of choice. Local recurrence is scarce. Due to the very limited number of cases, data regarding the long-term survival of patients are lacking.

Female↗

PubMed2004

Impact of FDG-PET for staging of oesophageal cancer.

BACKGROUND AND AIMS: Treatment of oesophageal cancer depends on staging and the general health of the patient. In stages I-II b, as well as in some stage III diseases, surgical resection remains the therapy of choice for cure, but a curative approach is not possible in stage IV. In our hospital we give preoperative radio-chemotherapy to all patients with an oesophageal cancer T>1, Nx, M0. Therefore, the main purpose of the clinical staging of oesophageal cancer is the exclusion of M1 and T4 disease with infiltration into the tracheobronchial system or the aorta. The aim of the investigation was the assessment of positron emission tomography for detection of M1 disease. PATIENTS/METHODS: Between 1998 and 2002, 84 patients with oesophageal cancer (64% squamous cell carcinoma and 36% adenocarcinoma) were enrolled into the study. Of these, 48.8% were operated on; 35.7% of the patients were not operated on, for oncological reasons, 7.1% for medical reasons, 3.6% chose not to be operated on, and, for unknown reasons, 4.8% were not operated on. RESULTS: Twenty-five patients had stage IV disease or additional, synchronous cancer of the head and neck ( n=2). As the only investigational procedure, positron emission tomography revealed M1 stage in 11 of 25 patients (44%). In 13/25 (52%) both computed tomography and positron emission tomography revealed stage IV disease. False positive results by positron emission tomography were observed in three patients. The sensitivity and specificity of positron emission tomography (PET) was 0.96 and 0.95, respectively. Most of the metastases detected by PET only, were localised within the neck, liver and bone. With regard to the 66 of 84 patients deemed medically fit for operation and without local infiltration into the tracheobronchial system (T4) PET as the only imaging procedure changed the therapeutic strategy in 11 of 66 (16.6%) patients with to M1 disease. CONCLUSION: Our results demonstrated clearly the impact of the PET scan for decision-making in patients with oesophageal carcinoma. PET should be performed prior to therapy with curative intention. However, addition of a computed tomography scan of the neck might reduce the rate of unexpected metastases detected by PET.

Adult↗

PubMed2004

Heterotopic pancreatitis with obstruction of the major duodenal papill--a rare trigger of obstructive orthotopic pancreatitis.

BACKGROUND: Heterotopic pancreas appears in 0.5 to 13% of autopsies. The most frequent locations are stomach, duodenum or upper jejunum. Pancreatitis in heterotopic pancreas is rarely described, and clinical symptoms caused by this heterotopic inflammation are uncommon. METHOD: We report a case of heterotopic pancreatitis localized in the major duodenal papilla causing biliary obstruction and mimicking a pancreatic head tumor. Clinically and radiologically, malignancy was suspected. Preoperative biopsies showed only fibrosis. A pylorus preserving resection of the pancreatic head was performed followed by an uneventful postoperative course. RESULT: Macroscopically, in the periampullary region on the pancreatic side a thickened duodenal wall with multiple lobules and cysts was found, compressing the common bile duct. Microscopic examination showed heterotopic pancreas with inflammatory lesions surrounding the ampulla. In the orthotopic pancreas a diffuse chronic pancreatitis with marked inflammation, fibrosis and atrophy of exocrine tissue was found. CONCLUSION: In our case it was impossible to differentiate between chronic pancreatitis and pancreas carcinoma preoperatively. Radiological findings and endoscopic biopsies were not sufficient to distinguish heterotopic pancreatitis from other tumors of the pancreatic head. Clear diagnosis could only be made by complete histological examinations after pancreatic head resection, being the treatment of choice for pancreatic head tumors of unclear dignity. The differential diagnosis of heterotopic pancreatitis as trigger of unclear enlargement of the pancreatic head is very seldom.

Cholestasis↗

PubMed2004

Influence of nitric oxide on microcirculation in pancreatic ischemia/reperfusion injury: an intravital microscopic study.

Recently, protective effects of nitric oxide donors in pancreatic ischemia/reperfusion (IRI) injury have been described. Their role in post-ischemic microcirculation was previously not investigated. Ischemia reperfusion was induced in an isolated pancreatic tail segment in situ. Animals were randomized to four experimental groups (n=7 animals/group), the control group (CO) received saline as placebo. Treatment groups received either sodium nitroprusside (SN) 5 min before until 2 h after reperfusion, L-arginine (LA) 30 min before reperfusion until 2 h after reperfusion or sodium nitroprusside and L-arginine (SNLA) together. After induction of ischemia (2 h) post-ischemic microcirculation was observed for 2 h by intravital-fluorescence microscopy. Functional-capillary density (FCD), leukocyte adherence in post-capillary venules (LAV) and histological damage were analysed. After reperfusion FCD decreased in all groups (P<0.05). FCD was significantly restored in all groups with administration of nitric oxide donors after reperfusion (P<0.05) as compared to CO without significant difference between the individual nitric oxide donor groups. Leukocyte adherence was significantly increased 1 h and 2 h after reperfusion (P<0.001) as compared to baseline, which was lower in all nitric oxide donor groups. Histological damage in the pancreatic tail-segment was significantly reduced in nitric oxide donor groups (P<0.01). Administration of nitric oxide donors might be useful in ischemia-reperfusion injury of the pancreas by its protective effect on microcirculation and inflammatory reaction.

Animals↗

PubMed2004

Endoscopic management of pancreatic fistulas secondary to intraabdominal operation.

BACKGROUND: Pancreatic fistulas may arise secondary to several disorders of the pancreas. Although approximately 70% of pancreatic fistulas close with nonoperative management, this course of treatment usually takes several weeks or even months. To reduce this long period, closures with fibrin glue have been attempted in the past. In this study, we describe the course, management, and outcome of eight patients with postoperative external pancreatic fistulas of the pancreatic body and tail that arose after oncologic operations in the upper abdomen. METHODS: All eight cases were treated by external drainage, insertion of an endoprosthesis into the pancreatic duct, and closure of the fistula with fibrin glue. RESULTS: Immediately after this intervention, secretion from the fistulas was absent in all cases. None of the patients developed abscesses, recurrent fistulas, or complications associated with the fibrin glue. CONCLUSION: The early endoscopic management of postoperative pancreatic fistula with an approach combining internal drainage of the pancreatic duct and external occlusion of the fistula with fibrin glue is expeditious and beneficial.

Cholangiopancreatography, Endoscopic Retrograde↗

PubMed2004

High levels of C-reactive protein after simultaneous pancreas-kidney transplantation predict pancreas graft-related complications and graft survival.

BACKGROUND: Although pancreas graft-related complications are frequent after simultaneous pancreas-kidney transplantation (SPK), there are no parameters predicting the risk for these complications. METHOD: A two-center retrospective study was performed in 97 patients who underwent SPK to investigate the peak serum value of c-reactive protein (CRP) during the first 72 hr after SPK in view of graft-related complications and graft survival. RESULTS: Mean peak CRP was 115.6 +/- 71.5 mg/L. Mean peak CRP was higher in patients needing relaparotomy (n=31) (136.4 vs. 105.8 mg/L, P=0.048), especially when postoperative bleeding was excluded (P=0.015); in patients with graft pancreatitis (P=0.03); and in patients with graft loss (n=19; P<0.001) compared with patients without these complications. With a cut-off of peak CRP at the level of mean plus 1 SD (187.05 mg/L), there was a significantly higher incidence of relaparotomies (P=0.01; bleedings excluded: P=0.003), graft pancreatitis (P=0.03), and pancreas graft loss (P<0.0001) in patients with high peak CRP compared with patients with low peak CRP. No differences were noticed with regard to rejection rate, mortality, and kidney graft loss. CONCLUSION: Our findings suggest that peak CRP is a helpful parameter in predicting pancreas graft-related complications and pancreas graft survival after SPK. Our results also stress the importance of early graft damage in pancreas transplantation.

Adult↗

PubMed2004

Ischemic preconditioning attenuates capillary no-reflow and leukocyte adherence in postischemic pancreatitis.

BACKGROUND AND AIMS: Ischemic preconditioning (IPC) has been shown to protect several organs from ischemia-reperfusion injury. Postischemic microvascular dysfunction is considered to be the key mechanism of early graft pancreatitis after transplantation. The aim of the study was to determine whether brief ischemia and reperfusion before prolonged ischemia followed by reperfusion is protective in respect to microcirculatory derangement in postischemic pancreatitis. METHODS: In an in-situ model of ischemia-reperfusion was induced in the isolated pancreatic tail segment. Wistar rats were randomized to one group ( n=7/group) with 2-h ischemia and reperfusion (I/R) and another group with 10-min ischemia and 10-min reperfusion (IPC) before the prolonged ischemia time. Microcirculation was observed for 2 h by intravital-fluorescence microscopy that analyzed functional capillary density and leukocyte adherence in postcapillary venules. Histological damage was quantified by a semiquantitative score (edema, vacuolization, PMN infiltration, necrosis). RESULTS: IPC resulted in a significant improvement of functional capillary density (248+/-20 vs 372+/-8 cm(-1), P<0.001), a significant reduction in leukocyte adherence in postcapillary venules (476+/-79 vs 179+/-15 cells/mm(2), P<0.001) and in significantly lower histological damage (score 9+/-0.8 vs 5+/-1.4, P<0.001), when compared with the ischemia-reperfusion group. CONCLUSION: IPC reduces pancreatic inflammatory reaction by preservation of postischemic microcirculation. Therefore, it might become a useful procedure before organ procurement in pancreas transplantation.

Acute Disease↗

PubMed2004

[Leakage after biliary and pancreatic surgery].

The frequency of anastomotic leaks after pancreatic resection is still significant. The majority of such leaks will heal without major clinical symptoms. In one fifth of patients, however, the sequelae of pancreatic leakage are serious and sometimes life-threatening. Management of such leaks ranges from local drainage to operative revision and completion pancreatectomy. The frequency of anastomotic leakage depends on a series of patient- and organ-specific risk factors. Surgical experience also plays a major role. Whether the prophylactic application of octreotide is able to reduce the frequency of pancreatic leaks is still a matter of debate. Leaks from direct bile duct sutures or biliodigestive anastomoses are rather seldom. Their clinical importance is limited. In case of a leak after direct bile duct anastomosis, endoscopic insertion of a stent seems to be the therapy of choice. Leaks from biliodigestive anastomoses which are diagnosed during the first 3 postoperative days should be treated by immediate operative revision. Late biliary leaks can be treated by local drainage. The results of bile duct surgery, too, are clearly dependent on the experience of the operating surgeon.

Anastomosis, Surgical↗

PubMed2004

Apoptosis is caused by prolonged organ preservation and blocked by apoptosis inhibitor in experimental rat pancreatic grafts.

UNLABELLED: Apoptosis is a major mode of cell death after ischemia/reperfusion injury in several organs. The aims of this study were to evaluate apoptosis induction after different conditions of pancreas preservation and to investigate the impact of a caspase inhibitor on apoptosis induction in pancreatic grafts. METHODS: Inbred male Lewis rats served as donors and recipients. Apoptosis was detected using an in situ cell death detection kit and an apoptotic DNA ladder kit (Roche, Germany). An apoptotic index (AI) was defined as the number of apoptotic cells per field (400x) under a light microscope. The five groups included: group 1 (n = 5), normal pancreata; group 2 (n = 7), pancreata stored in University of Wisconsin (UW) solution (4 degrees C) for 6 hours (hr); group 3 (n = 7), pancreata preserved in UW solution (4 degrees C) for 18 hr; group 4 (n = 7), pancreata preserved in 0.9% saline (4 degrees C) for 6 hours; and group 5 (n = 5), pancreata preserved in 0.9% saline (4 degrees C) for 6 hours with Z-Asp-2,6-dichlorobenzoyloxymethylketone (caspase inhibitor) treatment. The pancreatic grafts in all experimental groups underwent a 2-hr period of reperfusion after transplantation. RESULTS: The results in this study showed that the AI was not significantly increased among pancreatic grafts in group 2 compared to group 1 (P >.05). However, AI in group 3 was significantly higher than that in group 2 (P <.05). The highest AI was observed in group 4. Interestingly, AI in group 5 was significantly lower than that in group 4 (P <.01), and not significantly different from group 1 (P >.05). Apoptotic DNA ladders were detected in the pancreatic grafts in group 2, 3, and 4, but not in group 1 and 5. CONCLUSIONS: Prolonged preservation of pancreata in cold UW solution induces a dramatic increase in apoptotic cell death among the pancreatic grafts following Tx. This observation may well be an important mechanism of graft damage. A caspase inhibitor might be useful to inhibit apoptosis induction in pancreatic grafts.

Adenosine↗

PubMed2004

Islet autotransplantation combined with pancreatectomy for treatment of pancreatic adenocarcinoma: a case report.

Extensive pancreatectomy (EP) may increase the resection rate of pancreatic adenocarcinoma (PA). Unfortunately, EP often results in unstable diabetes. Recently, islet autotransplantation (auto-Tx) has offered the potential to prevent this metabolic disorder. Because of the fear of contamination of prepared islets by malignant cells, this procedure has so far not been used as a treatment for PA. We herein report a case of a 63-year-old nondiabetic patient who underwent EP combined with islet auto-Tx in an emergency operation following histologically proved R(0)-resection for PA (pT(3)pN(1)G(2)). Islets were isolated from the excised pancreas using a continuous digestion filtration device. The resultant preparation was injected into the portal vein. Owing to the moderate fasting hyperglycemia, postoperative exogenous insulin therapy was necessary (26 U/d). After discharge, the patient's daily insulin dose was gradually reduced. At 1-year follow-up the fasting C-peptide level was 0.66 ng/mL, and an oral glucose tolerance test (oGTT) and an intravenous (IV) glucagon stimulation (GS) showed functioning engrafted islets. The K-ras mutations were detected in the paraffin-embedded PA, but not in the prepared islets or in the peripheral blood. Computed tomographic (CT) imaging revealed neither local tumor recurrence nor liver metastases. At 2-year follow-up, the patient was on a balanced food regimen and gaining weight. Although he remains insulin-dependent (16 U/d), he is metabolically stable (HbA(1)(c) 5.9%). The fasting C-peptide level is 0.68 ng/mL. The peak value of C-peptide in response to oGTT was 0.92 ng/mL and to GS 0.89 ng/mL. At this time Ca19-9 and CEA are increased to 35.3 U/mL and 19.2 ng/mL, respectively. The patient died 2.5 years after operation owing to tumor recurrence. There was no evidence for liver metastases. We postulate that histologic evaluation (R(0)-resection) and detection of K-ras mutations may be useful techniques. However, islet auto-Tx after EP for adenocarcinoma should only be regarded for rescue therapy. Studies on strategies to exclude possible contamination of islet tissue with carcinoma cells are critically important.

Adenocarcinoma↗

PubMed2004

[Prophylactic splenectomy for splenic vein thrombosis in patients undergoing resection for chronic pancreatitis].

AIM: Chronic pancreatitis (CP) is the leading cause of splenic vein thrombosis (SVT). SVT occurs in about 15 % of patients with CP. The risk of variceal bleeding in SVT is approximately 10 %. Splenectomy is indicated in symptomatic SVT but its role in asymptomatic SVT is discussed controversially. Aim of our study was to evaluate the outcome of splenectomy performed during pancreatic resection in patients with CP and asymptomatic SVT. METHODS: 33 of 198 patients undergoing resection for CP underwent concomitant prophylactic splenectomy for asymptomatic SVT. Perioperative data were compared in the groups of patients with or without splenectomy. Follow-up was complete in 84 % (average 31 months). RESULTS: Median operative time, postoperative morbidity, reoperation rate and mortality were not different in patients with or without splenectomy. The median number of blood units transfused was higher in patients with prophylactic splenectomy (6 vs 4 units; p < 0.01). One complication of splenectomy (postoperative bleeding) occurred (3 %). During follow-up no variceal bleeding, no episode of postsplenectomy sepsis or thrombosis due to temporary thrombocytosis occurred. CONCLUSIONS: Complications of prophylactic splenectomy are rare and less frequent than reported episodes of variceal bleeding. In the presence of asymptomatic SVT splenectomy should be considered during pancreatic resection to facilitate surgery and to avoid further variceal bleeding.

Chronic Disease↗

PubMed2004

[Surgical therapy of inflammatory and malignant strictures of the common bile duct].

Although there are growing possibilities of interventional endoscopic treatment of benign and malignant stenosis of the distal common bile duct the definitive operative drainage by terminolateral hepaticojejunostomy is in many cases the therapy of choice. In patients with chronic pancreatitis and bile duct stricture the modified duodenum preserving pancreatic head resection ("Beger operation") enables a resection of the inflammatory mass together with a drainage of the bile. Of 391 patients from our clinic being operated due to a bile duct stricture 337 underwent a biliary drainage together with a pancreatic head resection. Early postoperative biliary complications were in 0.3 % strictures of the duct and 1.5 % bile fistulas. Half of those complications could be managed conservatively. In high volume centers the operative therapy of distal common bile duct stenosis is a safe procedure with high patency rate.

Anastomosis, Surgical↗

PubMed2004

Pancreas graft thrombosis: is there a role for trypsin.

PURPOSE: Thrombosis of the pancreas graft is the main cause of early graft loss in pancreas transplantation. We investigated whether hypercoagulability develops locally in the pancreas and contributes to thrombosis formation because of ischemia or reperfusion injury. It was further hypothesized that this might be induced by excessive intravascular trypsin activity. METHODS: Ten Patients undergoing pancreas transplantation were studied. In addition to the standard operation a 14 French catheter was inserted in the distal part of the splenic vein of the pancreas graft. After reperfusion blood samples were drawn simultaneously from the splenic vein of the pancreas graft (local samples) and the radial artery (systemic samples) at 0,1,2,5,10,30, and 60 minutes after reperfusion. RESULTS: After reperfusion a progressive hypercoagulability developed locally in the pancreas as seen by an increase of thrombin-antithrombin complexes and only a transient increase of plasmin-antiplasmin complexes. In addition antithrombin 3 and protein c decreased systemically. The alterations seem not to be triggered by trypsin because trypsin activity locally remained low despite trypsinogen release and activation as assessed by trypsinogen activation peptides. CONCLUSION: Local hypercoagulability might contribute to the development of graft thrombosis, however, the mechanism seems not to be related to ectopic trypsin activation.

Antithrombins↗

PubMed2003

Biocompatibility and surface structure of chemically modified immunoisolating alginate-PLL capsules.

Grafting of encapsulated living cells has the potential to cure a wide variety of diseases. Large-scale application of the technique, however, is hampered by insufficient biocompatibility of the capsules. A major factor in the biocompatibility of capsules is inadequate covering of the inflammatory poly-L-lysine (PLL) on the capsules' surface. In the present study, we investigate whether tissue responses against alginate-PLL capsules can be reduced by crosslinking the surface of the capsules with heparin or polyacrylic acid. Our transplant study in rats shows a tissue response composed of fibroblasts and macrophages on alginate-PLL-alginate and alginate-PLL-heparin capsules that was completely absent on alginate-PLL-polyacrylic acid capsules. Atomic force microscopy analyses of the capsules demonstrates that the improved biocompatibility of alginate-PLL-capsules by polyacrylic acid coating should not only be explained by a more adequate binding of PLL but also by the induction of a smoother surface. This study shows for the first time that biologic responses against capsules can be successfully deleted by chemically crosslinking biocompatible molecules on the surface of alginate-PLL capsules.

Acrylic Resins↗

PubMed2003

Value of ultrasound in the diagnosis of acute appendicitis: interesting aspects.

OBJECTIVE: The value of ultrasound in the diagnosis of acute appendicitis is still unclear. Both, studies with excellent and such with disappointing results have been published. The aim of this investigation was to answer the question, whether the results of these studies depend on study design, the investigating clinical department, or the number of ultrasound investigators. METHODS: A systematic literature research (PubMed (NLM) database) was performed. Of 99 publications dealing with ultrasound in the diagnosis of acute appendicitis, 69 were relevant to investigate the value of ultrasound in suspected appendicitis. RESULTS: Results of single-center studies (sensitivity 81.6%, specificity 89.8%, accuracy 85.7%) are better then those of multi-center trials (38.3%, 87.6%, 62.9%). There are no distinct differences between the investigating departments (surgeons 78.9%, 88.9%, 86.0%; radiologists 83.1%, 88.1%, 83.5%; mixed 77.8%, 87.1%, 79.4%, no specification 73.8%, 87.1%, 80.45.9%). Less than 10 investigators showed better diagnostic values (84.3%, 86.8%, 85.6%) compared to studies with 10 or more investigators (64.7%, 88.6%, 67.7%). CONCLUSION: The results of multi-center trials are disappointing and the good results of single-center studies do not reflect surgical everyday life. However, excellent results can be obtained if the investigation is restricted to a few specialists irrespectively of the clinical department.

Acute Disease↗