PubMed Health⌕ Search

Biomedical subjects

H Helmberger

Publications and source records attributed to H Helmberger.

At least 19 recordsLinked to original sources
PubMed2005

[Inflammatory diseases of the gall bladder and biliary system. I. Imaging--cholelithasis--inflammation of the gall bladder].

Cholelithiasis is the most common affliction of the gallbladder and biliary tract. Including its complications, gallstone disease represents the basis for cholecystitis and cholangitis in the majority of cases. Inflammatory diseases of the biliary system are divided into acute and chronic forms originating from the gallbladder as well as from the biliary tract. Although acute calculous cholecystitis is the most common form, gangrenous, and emphysematous inflammation of the gallbladder as well as gallbladder empyema are included in this group of diseases. In the chronic forms, calculous and acalculous inflammation is also differentiated. Recent developments in cross-sectional imaging in sonography, computed tomography, and magnetic resonance imaging offer numerous tools for depicting the biliary system with high diagnostic accuracy. Invasive imaging modalities of the biliary system are mainly used for therapeutic aspects.

Biliary Tract Diseases↗
PubMed2005

[Inflammatory diseases of the gall bladder and biliary system. II. Acute and chronic inflammation of the biliary system--primary biliary cirrhosis].

Inflammatory diseases of the biliary tract are divided into acute and chronic forms. Acute inflammation of the biliary tree is ascending cholangitis. Among chronic forms of the disease, primary sclerosing cholangitis, parasitic infection of the biliary tract, AIDS cholangiopathy, and chemotherapy cholangitis are recognised. Primary biliary cirrhosis and chronic inflammation of the papilla are also categorized within this group of inflammatory diseases of the biliary tree. Cross-sectional imaging modalities, such as sonography, computed tomography and magnetic resonance imaging, offer numerous possibilities for depicting the biliary system with high diagnostic accuracy. In contrast to the gallbladder, invasive imaging modalities of the biliary tree are also used for diagnostic purposes in addition to their therapeutic aspects.

Acute Disease↗
PubMed2003

Y-nitinol airway stent for management of central airway compression due to metastatic colon cancer.

Tumor masses in the area between the esophagus and the tracheobronchial tree can lead to complications involving both systems, mainly strictures and compressions. Malignant esophageal strictures are nowadays often treated by insertion of a metal stent which, however, can cause airway compression especially in the proximal area. We present here a new method of creating a Y-stent out of two self-expandable tracheal nitinol stents, utilizing fiber bronchoscopy, in a 55-year-old woman with advanced colon cancer metastastic to the mediastinum. The endo-Y-stent technique can be performed with the patient under sedation and having topical anesthesia. The opening through which the second tracheal stent must be placed for the Y construction is created by laser. In this case, the patient suffered from airway compression which was efficiently relieved by this method. Within a short time the endo-Y-stent provides effective restoration and maintenance of airway patency in patients with tumor compression in the region of the esophagus and airway, and in those with airway compression following esophageal stenting. Expertise in both stent implantation and laser application is, however, mandatory.

Bronchi↗
PubMed2002

Monitoring of tumour glucose metabolism by PET in a phase I study evaluating hormonal therapy in advanced pancreatic cancer.

BACKGROUND: Positron emission tomography (PET) determines therapy-induced changes in tumour glucose utilization. Experimental data indicate that cholecystokinin (CCK) stimulates pancreatic cancer growth. In this study in patients with advanced pancreatic cancer, we evaluated the use of fluorodeoxyglucose (FDG) PET compared with magnetic resonance imaging (MRI) in monitoring hormonal therapy using a highly selective, non-peptide CCK receptor antagonist (SR 27897B). METHODS: Nineteen patients were enrolled on a 28-day course of SR 27897B. Initially, 4 patients received 20 mg of SR 27897B; 9 patients received 40 mg; and 6 patients 80 mg. Imaging studies, including FDG-PET and MRI, were performed at baseline and on days 14 and 28. RESULTS: No significant changes in FDG uptake by the primary tumours were observed. Rate of progression of disease was 11 (61%) of 18 evaluable patients by MRI. Median survival of all patients enrolled was 2.7 months. SR 27897B was fairly well tolerated at all doses tested. The most common side effects were gastrointestinal disorders such as diarrhoea, flatulence and nausea. CONCLUSION: SR 27897B, when used alone at the limited doses employed, led neither to an impairment of tumour glucose metabolism nor to a reduction of tumour size in advanced pancreatic cancer.

Adenocarcinoma↗
PubMed2001

Prediction of response to preoperative chemotherapy in adenocarcinomas of the esophagogastric junction by metabolic imaging.

PURPOSE: Preoperative chemotherapy in patients with gastroesophageal cancer is hampered by the lack of reliable predictors of tumor response. This study evaluates whether positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) may predict response early in the course of therapy. PATIENTS AND METHODS: Forty consecutive patients with locally advanced adenocarcinomas of the esophagogastric junction were studied by FDG-PET at baseline and 14 days after initiation of cisplatin-based polychemotherapy. Clinical response (reduction of tumor length and wall thickness by > 50%) was evaluated after 3 months of therapy using endoscopy and standard imaging techniques. Patients with potentially resectable tumors underwent surgery, and tumor regression was assessed histopathologically. RESULTS: The reduction of tumor FDG uptake (mean +/- 1 SD) after 14 days of therapy was significantly different between responding (-54% +/- 17%) and nonresponding tumors (-15% +/- 21%). Optimal differentiation was achieved by a cutoff value of 35% reduction of initial FDG uptake. Applying this cutoff value as a criterion for a metabolic response predicted clinical response with a sensitivity and specificity of 93% (14 of 15 patients) and 95% (21 of 22), respectively. Histopathologically complete or subtotal tumor regression was achieved in 53% (eight of 15) of the patients with a metabolic response but only in 5% (one of 22) of the patients without a metabolic response. Patients without a metabolic response were also characterized by significantly shorter time to progression/recurrence (P =.01) and shorter overall survival (P =.04). CONCLUSION: PET imaging may differentiate responding and nonresponding tumors early in the course of therapy. By avoiding ineffective and potentially harmful treatment, this may markedly facilitate the use of preoperative therapy, especially in patients with potentially resectable tumors.

Adenocarcinoma↗
PubMed2000

[Hepatocellular carcinoma with extension per continuitatem into the right atrium].

HISTORY AND CLINICAL FINDINGS: A 61-year-old asymptomatic patient presented with a hepatocellular carcinoma and a history of 11 cycles of transarterial chemoembolization. Staging investigations revealed an enlarged hepatic tumour and a right atrial mass. INVESTIGATIONS: Computed tomography of chest and abdomen showed a progressive tumour in both hepatic lobes with extension to the inferior vena cava, through the diaphragma and to the right atrium. TREATMENT AND COURSE: The patient received supportive treatment and died 3 months later. CONCLUSION: Inspite the incidence of 1-4%, hepatocellular carcinoma with extension to the heart has been diagnosed rarely. Although treatment is limited, early diagnosis by abdominal echography or echocardiography is necessary for the interpretation of cardiogenic symptoms and the prognosis.

Abdomen↗
PubMed2000

[Chronic infections of the biliary system].

Chronic inflammation of the gallbladder and the biliary tract due to infections are rare, compared to common cholelithiasis and acute biliary inflammation. This group of diseases includes, besides of chronic cholecystitis with cholelithiasis, also chronic gallbladder inflammation without stones, gallbladder hydrops and porcelain gallbladder. The most common form of chronic biliary tract infection is primary sclerosing cholangitis, while infection due to parasites like oriental cholangiohepatitis is very rare in Europe. Using imaging modalities like ultrasonography, computed tomography and magnetic resonance imaging, normally, besides of porcelain gallbladder, only indirect signs of the disease may be documented. However, when i.v. cholangiography, endoscopic-retrograde cholangiography, percutaneous transhepatic cholangiography or MR-cholangiography are performed, depiction, especially of the biliary tree, is feasible. Differentiation of benign stricture and malignant tumor stenosis is problematic unrelated to the imaging modality used. Due to the unspecific signs of the disease, diagnosis may not be made from imaging alone, but a clinical suspicion may be strengthened.

Biliary Tract↗
PubMed2000

Preoperative evaluation of pancreatic masses with positron emission tomography using 18F-fluorodeoxyglucose: diagnostic limitations.

Identification of pancreatic cancer in patients presenting with an enlarged pancreatic mass is a major diagnostic problem. Positron emission tomography (PET) using the radiolabeled glucose analogue 18F-fluorodeoxyglucose (FDG) has been suggested to provide excellent accuracy for noninvasive determination of suspicious pancreatic masses. We conducted a prospective study to verify these results. Forty-two patients admitted for pancreatic surgery underwent PET scanning. Image analysis was based on visual film evaluation and quantification of regional tracer uptake. PET imaging was visually analyzed by three observers blinded for the results of other diagnostic tests; they qualitatively graded the scans using a five-point scale (I = low to V = high) for the presence and intensity of focal FDG uptake. Diagnosis was proven by histology (n = 38) or follow-up (n = 4). Furthermore, the results of PET were compared with helical computed tomography (CT) and conventional ultrasonography (US), done during the routine diagnostic workup before pancreatic cancer surgery. Regarding only the results with scores of IV and V as positive for representing definite malignancy yielded a sensitivity of 71% and a specificity of 64% for film reading. Quantification of regional tracer uptake contributed no significant diagnostic advantage for differentiation between benign and malignant tumors. Helical CT revealed a sensitivity of 74% and a specificity of 45.5% and abdominal US 56% and 50%, respectively. We concluded that PET imaging provides only fair diagnostic accuracy (69%) for characterizing enlarged pancreatic masses. PET does not allow exclusion of malignant tumors. In doubtful cases, the method must be combined with other imaging modalities, such as helical CT. The results indicate that the number of invasive procedures is not significantly reduced by PET imaging.

Adenocarcinoma↗
PubMed2000

[Functional MR-pancreatography with secretin. A comparison of imaging quality and diagnostic value].

PURPOSE: The aim of the present study was to assess imaging improvement and diagnostic value of secretin stimulated MR-pancreatography (MRP) compared to conventional MRP. MATERIALS AND METHODS: 50 patients were studied with a 1.0 T system using a single-shot-TSE sequence (RARE). Imaging quality and diameter of the different parts of the pancreatic tract and diagnoses were monitored before and after secretin. RESULTS: The visualization of the normal main pancreatic duct (MPD) was improved significantly in head, body and tail. Side branches were not depicted at all. Even in chronic pancreatitis a significant improvement of imaging quality could be observed, but only in patients without duct dilation before secretin. In advanced disease with duct dilation, secretin stimulation provided no further diagnostic improvement. CONCLUSIONS: In conclusion, secretin increases the diagnostic value of MRP especially in patients with normal or non-dilated native MPD and may help to avoid unnecessary invasive procedures such as ERCP.

Adolescent↗
PubMed1998

[Diagnosis of bronchial carcinoma].

In addition to conventional chest X-rays in AP and lateral projection, computed tomography of the chest, upper abdomen, and head, precutaneous ultrasonography of the abdomen, and bone scintigraphy represent the standard procedures for the primary diagnosis and staging of bronchial carcinoma. Magnetic resonance imaging should be reserved for special situations and patients with allergy to i.v. contrast medium. The clinical value of positron emission tomography (PET) primarily with respect to lymph-node staging is currently being evaluated in ongoing studies. Due to the high sensitivity of the listed staging modalities in combination with rather low specificity, there is a general tendency towards "over staging", which carries certain risk particularly for potentially operable patients. Consequently the criteria which indicate inoperability (T3, T4, N2, N3 and, in individual cases, M1) have to be confirmed histologically by biopsy employing interventional techniques or even by explorative thoracotomy before definite therapeutic decisions are made.

Biopsy↗
PubMed1998

[Rational diagnosis of the bile ducts].

Since the introduction of MR cholangiography (MRC) diagnostic imaging of the biliary tract has been significantly improved. While percutaneous ultrasonography is still the primary examination, computed tomography (CT), conventional magnetic resonance imaging (MRI), as well as the direct imaging modalities of the biliary tract--i.v. cholangiography, endoscopic-retrograde-cholangiography (ERC), and percutaneous-transhepatic-cholangiography (PTC) are in use. This article discusses the clinical value of the different diagnostic techniques for the various biliary pathologies with special attention to recent developments in MRC techniques. An algorithm is presented offering a rational approach to biliary disorders. With further technical improvement shifts from ERC(P) to MRC(P) for biliary imaging could be envisioned, ERCP further concentrating on its role as a minimal invasive treatment option.

Biliary Tract Diseases↗