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M Gebel

Publications and source records attributed to M Gebel.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Sonographic diagnosis of an unusual recurrence of Chilaiditi syndrome after hemicolectomy].

A 71-year old patient presented with acute abdominal pain, nausea and emesis 3 months after right hemicolectomy for Chilaiditi's syndrome. The initial ultrasound examination revealed a loop of thick walled small intestine between the anterior surface of the right liver lobe and the diaphragm. In addition, small amounts of perihepatic fluid were found. The chest x-ray confirmed a recurrence of Chilaiditi's syndrome with intestinal gas under the right diaphragm. Elongation and flaccid of intestinal and hepatic suspensory ligaments are thought to be the principal predisposing factors. However, in our patient, a wedge-shaped enlarged lobus caudatus served as a guide rail for the bowel and facilitated access to the space under the right diaphragm. Although the patient recovered completely after 3 days of conservative therapy a high risk of recurrence remains. In summary, ultrasound examination can reliably diagnose Chilaiditi's syndrome and should also be used, as the method of choice in the follow-up of this rare syndrome, thus avoiding unnecessary x-ray exposure.

Abdomen↗
PubMed2000

[The research situation in abdominal sonography in the gastroenterology departments of university hospitals in the Federal Republic of Germany].

Objective of the present study is to provide a current overview of the present state of research in abdominal ultrasound in the gastroenterological departments of university hospitals in Germany. We conducted a survey assessing the number of research projects in progress, sources of financial support, sponsorship by the private sector and publications generated. Reports from 28 of 35 gastroenterological departments responding to the survey indicated that a total of 124 research projects were in progress during the survey period, for an average of 3.5 projects per department. Clinical issues were addressed in 78 studies, technical questions in 33 studies and other questions in 13 studies. Of the 117 publications generated, 50 appeared in German-language journals and 67 in English-language journals. At present, neither the German Research Association (DFG) or the European Union (EU) is financially underwriting an ultrasound research project in the gastroenterological department of any German university hospital. Ultrasound remains the most frequently applied diagnostic imaging technique in gastroenterology. In order to convert the enormous technological progress into improved diagnostic capabilities, there must be a significant expansion in research support for gastrointestinal ultrasound.

Abdomen↗
PubMed2000

Two different mechanisms for activation of cyclic PIP synthase: by a G protein or by protein tyrosine phosphorylation.

The biosynthesis of the functional, endogenous cyclic AMP antagonist, prostaglandylinositol cyclic phosphate (cyclic PIP) is performed by the plasma membrane-bound enzyme cyclic PIP synthase, which combines prostaglandin E (PGE) and activated inositol phosphate (n-IP) to cyclic PIP. The Km values of the enzyme for the substrates PGE and n-IP are in the micromolar range. The plasma membrane-bound synthase is activated by fluoride, by the stable GTP analog GMP-PNP, by protamine or biguanide, by noradrenaline, and by insulin. The activation by protamine or biguanide and fluoride (10 mM) is additive, which may indicate the presence of two different types of enzyme, comparable to phospholipase Cbeta and phospholipase Cgamma. Plasma membrane-bound cyclic PIP synthase is inhibited by the protein tyrosine kinase inhibitor tyrphostin B46 with an IC50 of 1.7 microM. However, the solubilized and gel-filtrated enzyme is no longer inhibited by tyrphostin, indicating that the activity of cyclic PIP synthase is connected with the activity of a membrane-bound protein tyrosine kinase. Cyclic PIP synthase activity of freshly prepared plasma membranes is unstable. Upon freezing and rethawing of liver plasma membranes, this instability is increased about 2-fold. Protein tyrosine phosphatase inhibitors [vanadate, fluoride (50-100 mM)] stabilize the enzyme activity, but protease inhibitors do not, indicating that inactivation of the enzyme is connected with protein tyrosine dephosphorylation. Cyclic PIP synthase is present in all tissues tested, like brain, heart, intestine, kidney, liver, lung, skeletal muscle, spleen, and testis. Apart from liver, cyclic PIP synthase activity in most tissues is rather low, but it can be increased up to 5-fold when protein tyrosine phosphatase inhibitors like vanadate are present in the homogenization buffer. Preincubation of cyclic PIP synthase of liver plasma membranes with the tyrosine kinase src kinase causes a 2-fold increase of cyclic PIP synthase activity, though this is certainly not the physiological role played by src kinase in intact cells. The data indicate that cyclic PIP synthase can be activated by two separate mechanisms: by a G protein or by protein tyrosine phosphorylation.

Adenosine Triphosphate↗
PubMed1999

[Atypical gallstone ileus: radiologic and sonographic findings].

We report on a case of an atypically located gallstone ileus as a rare complication of cholecystolithiasis. A 61-year old lady with a history of diabetes type II and nephrolitiasis presented with abdominal pain lasting for 8 days and with vomiting and diarrhoea. Physical examination revealed a palpable tumour and pain in the left lower abdomen. An extensive elevation of blood sugar, CRP and leukocytosis was found. Initially X-ray of the abdomen and sonography showed signs of a subileus. Additionally a 5 x 2 cm mass with dorsal shadowing was detected by ultrasound. Gallbladder and the biliary system were normal. The sonographic suspicion of a gallstone ileus was confirmed by a subsequent CT scan. Under operation the gallstone was found in the distal Jejunum. A gallstone ileus must be included in the differential diagnosis of a tumour in the left lower abdomen. A tumour with dorsal shadowing and signs of a subileus may be the only sonographic findings of a gallstone ileus.

Cholelithiasis↗
PubMed1999

Pitfall: a pseudo tumor within the left liver lobe presenting with abdominal pain, jaundice and severe weight loss.

A 51 year old male patient with a history of chronic alcohol consumption and recurrent pancreatitis was referred to our hospital with jaundice, epigastric pain, severe diarrhoea and weight loss of 28 kg within the last 12 months. A CT scan of the abdomen 4 months before admission had shown a pancreatitis with free fluid around the corpus and tail of the pancreas as well as dilated intrahepatic bile ducts and a cavernous transformation of the portal vein. Moreover, a tumor (3.5 x 3.0 x 3.6 cm) with irregular contrast enhancement was seen within the left liver lobe. The patient was referred to us for further evaluation and treatment. The initial B-Mode sonogram revealed a bull's eye like well defined lesion (8.1 x 7.5 x 7.0 cm) within the left liver lobe, consistent with a tumour or abscess. Prior to a diagnostic needle biopsy a PTCD was performed in this case presenting with dilated intrahepatic bile ducts and having a history of Billroth II operation. An additional colour coded Duplex Doppler ultrasonography demonstrated a visceral artery aneurysm and prevented us from performing the diagnostic puncture. The aneurysm was assumed to originate from a variant or a branch of the left hepatic artery. Angiography revealed a pseudoaneurysm of the pancreaticoduodenal artery and coil embolization was performed because of the increasing size and the risk of a bleeding complication. Postinterventional colour duplex ultrasound measurement showed no blood flow within the aneurysm. Retrospectively, the pseudoaneurysm must have led to a compression of the common bile duct, since the patient did not develop cholestasis after embolization and removal of the PTCD. Thus, a pseudoaneurysm of the pancreaticoduodenal artery must be included in the differential diagnosis of liver tumours in patients with chronic pancreatitis, despite its unusual localization near the liver. Therefore, we suggest that colour coded ultrasonography should be applied to any unclear, bull's eye like lesion, even though this method alone cannot exactly determine the origin of the pseudoaneurysm. Interventional angiography remains the gold standard for the diagnosis and therapy of visceral artery aneurysm.

Alcohol-Related Disorders↗
PubMed1999

Diagnosis of Chilaiditi's syndrome with abdominal ultrasound.

Chilaiditi's sign is a radiographic term used when the hepatic flexure of the colon is seen interposed between the liver and right hemidiaphragm. When symptomatic, this is Chilaiditi's syndrome. We report a case of a 70-year-old man who presented with abdominal pain, vomiting, singultus and constipation. Ultrasound was initially performed which showed an intestinal loop between the anterior surface of the right liver lobe and the diaphragm. The chest X-ray revealed colon gas under the right diaphragma and the abdominal CT-scan confirmed the hepatodiaphragmatic interposition of the colon. Colonic elongation and laxity of colonic and hepatic suspensory ligaments are the principal predisposing factors. The advantages of the abdominal ultrasound in the diagnosis and follow-up as well as possible complications and forms of therapy with this syndrome are discussed.

Abdominal Pain↗
PubMed1999

[Treatment of multilocular hepatocellular carcinoma (HCC) of 4.5 cm and 3.5 cm diameter using percutaneous ethanol injection in a patient with advanced liver cirrhosis].

UNLABELLED: Treatment of hepatocellular carcinoma (HCC) with percutaneous ethanol injection (PEI) is established for tumors up to 3 cm. We report on treatment of a multilocular HCC with a maximum size of 4.5 cm. CASE REPORT: In a 76-year-old woman with a liver cirrhosis (Child C) due to chronic hepatitis C HCC with two nodules (diameter 3.5 cm and 4.5 cm) was diagnosed. Because of the patient's reduced general state of health and the advanced cirrhosis surgical treatment and chemoembolization were declined. The two nodules were treated in ten settings during 15 weeks under ultrasound guidance with 85 ml of 96% ethanol. There were no severe side effects. The patient's general condition improved and serum alpha-fetoprotein concentration decreased from 21,126 to 800 micrograms/l. Seven months after the diagnosis of the HCC she was admitted to another hospital due to a cerebral hemorrhage. A few days later she died because of a pneumonia. In spite of detailed micro- and macroscopically investigation no tumor was found during the autopsy. This case report shows that HCC up to a diameter of 4.5 cm can be effectively treated by PEI. This treatment modality is cheap and well-tolerated even in patients suffering from advanced cirrhosis.

Aged↗
PubMed1998

Portohepatic vascular pathology and liver disease: diagnosis and monitoring.

A number of diseases alter the normal pathophysiology of the portohepatic vascular system. The impact of these changes depends on the severity of the disease and the involvement of the entrahepatic vasculature. Cirrhosis of the liver is not a vascular disease but the effects on the liver architecture result in severe disease often accompanied by hepatic vascular changes. Alcohol abuse and viral infections are the most common causes of cirrhosis. Portal hypertension (PHT) is one of the most frequently seen sequelae of liver cirrhosis. It results in the formation of porto-systemic collateral channels which may lead to varices and hemorrhage. Primary liver cancer is also strongly associated with liver cirrhosis. Hepatocellular carcinoma (HCC) is the most common liver cancer seen in patients with cirrhosis. There are four types of HCC based on its growth patterns: infiltrative, expansive, mixed and diffuse. Raised plasma levels of alpha-fetoprotein are a characteristic of HCC. However, this marker is unreliable in patients with smaller tumors. Ultrasound is an inexpensive, non-invasive and safe diagnostic technique used to detect portal vein changes in PHT and to identify HCC lesions in the liver. Grey scale ultrasound reveals the portal vein changes and the portal-systemic collaterals which typify PHT. The technique is most useful for diagnosis or confirmation of moderate to severe disease. HCC nodules have characteristic ultrasound patterns which help in differential diagnosis. Doppler ultrasound provides functional as well as anatomical information about blood flow in the liver and is especially useful in detecting HCC and the abnormal blood vessel architecture which surrounds a tumor. However, despite their usefulness, both imaging techniques have limitations which may be improved by the use of echo-enhancing agents. Levovist(R) is a galactose-based microbubble echo-enhancing agent which has an excellent safety profile and utility in enhancing ultrasound images of the liver. It markedly improves diagnostic confidence and reduces the percentage of non-diagnostic ultrasound scans in patients with abnormal liver pathologies. The use of echo-enhanced ultrasound to diagnose liver disease may obviate the need for more expensive and invasive diagnostic procedures.

Blood Flow Velocity↗
PubMed1998

A multicenter, prospective, open label, randomized, controlled phase IIIb study of SH U 508 a (Levovist) for Doppler signal enhancement in the portal vascular system.

PURPOSE: Assessment of the accuracy of SH U 508 A (Levovist) enhanced Doppler sonography in the evaluation of blood flow abnormalities in the portal vascular system. METHOD: In an open label, controlled, prospective multicenter study, patients referred for Doppler sonography of the portal vascular system were randomized to receive SH U 508 A if indicated or to an observation group (ratio of 4:1). Patients who had diagnostically insufficient Doppler signals received SH U 508 A (2.5 g [200, 300 or 400 mg/ml]), followed by confirmatory dynamic CT. Corresponding patients in the observation group received alternative imaging procedure(s). RESULTS: Of 588 patients 265 patients received SH U 508 A. In 253 (95.5%) of these patients a diagnosis was possible following administration of SH U 508 A (Levovist). Diagnostic confidence improved from 35.3% to 89.7%. If compared with dynamic CT, SH U 508 A enhanced Doppler had a sensitivity of 80.5% and a specificity of 89.7%. Whereas diagnosis was not possible with SH U 508 A enhanced Doppler in only 12 patients, a diagnosis was not possible in 29 patients with dynamic CT. SH U 508 A enhanced Doppler in particular improved visualization of the portal vein (15.6%), TIPS (15.8%), superior mesenteric vein (16.1%), collateral circulation (20.7%) and inferior mesenteric vein (25%). SH U 508 A was very well tolerated; only eight patients experienced minor adverse events possibly related to SH U 508 A administration. CONCLUSION: SH U 508 A enhanced Doppler improved the diagnostic confidence and visualization of the portal vascular system compared to base line scans with insufficient Doppler signal and proved reliable compared to dynamic CT.

Adult↗
PubMed1998

Sonography under Daylight Conditions.

PURPOSE: Gray scale image assessment in clinical ultrasound requires working in dim light or a dark room. Daylight conditions offer the advantage of shorter visual reaction time and enhanced visual perception. Look-up table manipulations could improve image brightness. MATERIALS AND METHODS: We investigated the possibility of brightness and contrast enhancement of coloured adaptive linear look-up tables (CALUT's) and their artifact resistance. Therefore under real-time conditions red/brown, green and blue CALUT's were calculated using the gray scale distribution (mean and standard deviation) of the actual image. The changes in contrast of several structural features (echo-poor and echogenic lesions, artifacts) were assessed by clinical investigators (n = 7). RESULTS: The CALUT's produced, independent of the original, images with constant brightness and contrast. Even under daylight conditions no artifacts appeared. Under scotopic conditions the red/brown CALUT's showed the best results compared to the unchanged image and the gray, green, and blue CALUT's. Hyper and hypoechoic differences with small contrast to the surrounding tissue are enhanced and can be detected more easily. CONCLUSION: Daylight sonography allows examination even in non-darkened rooms without loss of information. Eye adaptation to changing light conditions is no longer necessary; the offered image information is more suitable for the eye.

Algorithms↗
PubMed1998

[3D and color Doppler ultrasound evaluation of cystic space-occupying lesion near the head of the pancreas].

AIM: Differential diagnosis of cystic lesions in the abdomen may be very difficult. We present the clinical manifestation and the diagnostic steps of a rare case of an aneurysm of the gastroduodenal artery mimicking a cystic lesion. We also discuss the imaging methods we used to verify the diagnosis such as colour Doppler sonography and 3D-sonography. METHOD AND PATIENT: A 42-year old woman with chronic pancreatitis was admitted to our hospital after an extended diagnostic program (sonography, computed tomography and laparoscopy) with the diagnosis of a pancreatic pseudocyst with vascular erosion. Using conventional sonography we found a cystic lesion of 5 x 5 cm diameter with parietal deposits between pancreas and coeliac trunk. After colour Doppler sonography we found an arterial jet in the cystic tumor; initially the source of the jet seemed to be the hepatic artery. We referred the patient to our department of radiology with the diagnosis of hepatic artery aneurysm. The aneurysm was confirmed by the angiography and was embolised with coils in the same session. However, the source of the aneurysm was not the hepatic, but the gastroduodenal artery. By postangiographical 3D-sonography we could clearly reconstruct the relation of the aneurysm to the gastroduodenal artery. CONCLUSION: Colour Doppler sonography should be the first imaging tool for clarifying cystic lesions in the abdomen. 3D-sonography is a reliable and useful method to identify visceral vessels of the abdomen. Nowadays the "gold standard" angiography should preferably be used as a therapeutic procedure.

Adult↗
PubMed1998

Percutaneous sonographic gastrostomy: method, indications, and problems.

OBJECTIVES: This study evaluated the application of ultrasound (US) guidance in the percutaneous placement of gastric feeding tubes in patients in whom endoscopic placement of a nutrition tube is not possible. METHODS: Thirty-eight patients with upper gastrointestinal obstruction were entered in a prospective study with US-guided nutrition tube application. Feasibility of placement, side effects, and nutritional states were monitored for a mean follow-up of 4 months. RESULTS: Ultrasound allowed rapid puncture after filling of the stomach with water through a nasal tube in 34/38 cases. In four cases a total upper gastrointestinal obstruction required an initial stomach insufflation through a direct puncture. Puncture-related major complications were not observed. Minor complications during the observation time were one late dislocation, five cases with broken material after about 6 months (four could be changed by using the Seldinger technique), and two minor local infections. The nutrition through feeding tubes stabilized body weight and body composition parameters. CONCLUSION: The percutaneous sonographic gastrostomy (PSG) is a safe and minimally invasive procedure for enteral nutrition in all cases with upper gastrointestinal obstruction when endoscopic placement of a feeding tube is not possible. Percutaneous sonographic gastrostomy may help to stabilize the nutritional parameters and general condition in patients with malignant diseases.

Adult↗
PubMed1998

Clinical outcome of transfemoral embolisation in patients with arteriovenous malformations of the liver in hereditary haemorrhagic telangiectasia (Weber-Rendu-Osler disease).

BACKGROUND: Arteriovenous malformations of the liver in Osler's disease may present as high output cardiac failure. A few case reports suggested that treatment with arterial embolisation may have beneficial effects in such patients. AIMS: To investigate the efficacy and safety of this treatment modality in a prospective pilot study. PATIENTS AND METHODS: Four women and one man (aged 39-59 years) with the dominant hepatic manifestation of Osler's disease presented with symptoms of cardiac failure and elevated cardiac output. Arteriovenous malformations were treated in three to five sessions with arterial embolisation using coils. The outcome was analysed by measurement of cardiac output and scoring of clinical symptoms. RESULTS: Embolisation was technically feasible in all patients and adequate occlusion of vascular malformations was achieved in four patients. After completion of therapy symptoms improved in four patients, while one patient suffered from abdominal pain due to cholangitis. One patient died seven months after the embolisation treatment from variceal bleeding. Mean cardiac output significantly decreased from 14.2 (range 12-17.3) l/min to 8 (range 5.9-10.6) l/min (p = 0.043). After a median follow up of 23 months (range 7-50 months), three of five patients had a long lasting improvement of clinical symptoms and cardiac function. CONCLUSIONS: This first treatment series of patients with dominant hepatic involvement in Osler's disease indicates that arterial embolisation may prevent cardiac failure by significantly lowering cardiac output.

Adult↗
PubMed1998

[Enteroparesis caused by progressive fibrosis of the muscularis propria].

We would like to present the case of a 54-year-old patient who was admitted to the hospital with complaints of recurrent vomitus after food intake and associated weight loss. Endoscopy. barium X-ray of the small bowel and scintigraphy showed enteroparesis. Full-thickness biopsies achieved by explorative laparotomy revealed the pathological changes. The inner circular muscular layer was atrophic and replaced by fibrosis. The pathological findings were consistened with either visceral myopathy or isolated intestinal progressive systemic sclerosis. A sporadic nonfamilial type of visceral myopathy seems to be the most likely diagnosis in this case. Progressive systemic sclerosis seems to be unlikely as the patient presented with isolated gastrointestinal involvement and lack of appropriate autoantibodies. The diseases progression made an enteral supplementation impossible. Therefore a parenteral nutrition was started, which was characterized by a complicated clinical course. Persisting gastrointestinal complaints, recurrent port infections and lack of perspectives led to patient's diminished motivation for adequate sterile use of the port-system. This case report shows that besides the use of modern port-systems and antibiotics the psychological situation of patients treated with total parenteral nutrition is of great interest for optimal patient care.

Diagnosis, Differential↗
PubMed1998

3D-ultrasound in imaging, diagnosis and follow-up of an atypical hydatid cyst.

Abdominal ultrasonography is the procedure of choice to diagnose hydatid cysts caused by Echinococcus granulosus. Recently three-dimensional ultrasonography has become available for clinical application. We report a case of an atypical seronegative hydatid disease, in which the additional use of 3D-sonography improved the sonographic diagnosis, which was confirmed by a fine needle biopsie complicated by an anaphylactic reaction. In addition the potential advantage of 3D-ultrasonography in diagnosis and follow-up hydatid disease will be discussed, especially in the context of new alternative therapeutic options like chemotherapy with benzimidazoles or the percutaneous drainage by the PAIR procedure (puncture-aspiration-injection-re-aspiration).

Adult↗
PubMed1997

[Approaches to objective assessment of differences in tissue textures by ultrasound equipment as a contribution to quality assurance].

PURPOSE: For clinical investigators the increasing number of ultrasonic machines with different technological equipment makes it difficult to reliably assess their ability to differentiate between the textures of various tissues. We investigated a procedure for a standardised method to measure the tissue texture when using different ultrasonic machines. METHODS: The texture parameters concern brightness, standard deviation, coefficient of variation and spatial coefficient of variation. These were calculated for three tissue phantoms with changing levels of gain and distance. These parameters, well established in literature for speckle detection, texture differentiation and contrast monitoring were useful for rapid comparison of the texture differentiation achieved by several ultrasonic machines. RESULTS: A linear relationship between standard deviation and mean image brightness seems to be an important factor for the detection of small changes in ultrasonic textures. We noticed great differences between the various ultrasonic machines tested by us. The best parameter in our set was the spatial coefficient of variation. CONCLUSION: The method allows rapid orientation regarding the ability of a machine to distinguish between several textures depending on the brightness, and offers an opportunity of determining the best working point for a given machine.

Equipment Design↗
PubMed1997

[Duplex ultrasound characterization of hepatic vein blood flow in healthy probands].

PURPOSE: To characterise and standardise hepatic venous flow during the respiratory cycle in all three hepatic veins and to determine the most adequate measurement area within the vessel. METHOD: In 25 healthy subjects duplex Doppler measurements were performed of the right (RHV), middle (MHV) and left (LHV) hepatic vein. In full inspiration, mid-inspiration and expiration the maximum flow velocities of all three hepatic venous flow components (phase 1 to 3) were measured and a systolic to diastolic (S/D) ratio was determined. RESULTS: In full inspiration there was a decrease of the maximum flow velocities compared to mid-inspiration (p = 0.0001). In expiration there was an increase of the maximum flow velocities (p = 0.0005). The maximum flow velocities of the MHV in mid-inspiration were -0.21 +/- 0.019 m/s (phase 1), -0.16 +/- 0.016 m/s (phase 2) and 0.08 +/- 0.011 m/s (phase 3). The S/D ratio decreases on inspiration and increases on expiration. The maximum flow velocities of the LHV differed significantly from those of the RHV and MHV. The measurements of the RHV and MHV were both reliable. Measurements from central to peripheral within the hepatic veins showed a decrease in maximum flow velocities. CONCLUSION: For standardisation of hepatic venous flow measurements the respiratory state must be determined. The most adequate area for duplex Doppler ultrasound measurements is situated about one or two centimetres from the orifice of the vena cava.

Adult↗