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H Ringl

Publications and source records attributed to H Ringl.

9 recordsLinked to original sources
PubMed2002

[Electrical impedance scanning in the differentiation of suspicious breast lesions: comparison with mammography, ultrasound and histopathology].

PURPOSE: To assess the value of Electrical Impedance Scanning (EIS) in the differentiation of suspicious breast lesions in comparison to mammography (MG) and ultrasound (US). METHODS: In 95 female patients (median 53.1 ys) 95 suspicious breast lesions (BI-RADS TM III - V) in MG or US underwent targeted EIS (TransScan TS 2000(R); TransScan Medical, Israel; Siemens Elema, Sweden). Histopathologic proof (vacuum-assisted biopsy or surgical biopsy) was obtained in all cases. MG, US and EIS were independently assessed by two radiologists in consensus. Chi-square tests as well as variance-analysis for ROC-statistics were performed. RESULTS: Of 95 lesions, 44 were benign, 51 malignant. Sensitivity, specificity, positive and negative predictive values were, respectively for MG 95.3 %, 23.5 %, 51.3 % and 85.7 %, for US 86.5 %, 44.2 %, 57.1 % and 79.1 %, for EIS 77.3 %, 82.3 %, 79.1 % and 80.8 %. The ROC-analysis revealed a significant greater area under the curve for EIS than for MG and US. The sensitivity for EIS was higher in lesions < 10 mm (n = 26; 100 %) and in invasive cancers (n = 31; 80.6 %). The negative predictive value of EIS was higher in BI-RADS TM-IV-lesions (83.9 %) as well as in dense breast parenchyma on the mammogram (86.7 %). CONCLUSION: EIS shows potential adjunctive value to MG and US in the differentiation of suspicious breast lesions.

Adult↗
PubMed1997

Virtual endoscopy of the paranasal sinuses using perspective volume rendered helical sinus computed tomography.

Our goal was to use three-dimensional information obtained from helical computed tomographic (CT) data to explore and evaluate the nasal cavity, nasopharynx, and paranasal sinuses by simulated virtual endoscopy (VE). This was done by utilizing a new image reconstruction method known as perspective volume rendering (PVR). Thin-section helical CT of the nasal cavity, nasopharynx, and paranasal sinuses was performed on a conventional CT scanner. The data were transferred to a workstation to create views similar to those seen with endoscopy. Additional views not normally accessible by conventional endoscopy were generated. Key perspectives were selected, and a video "flight" model was choreographed and synthesized through the nasal cavity and sinuses based on the CT data. VE allows evaluation of the nasal cavity, nasopharynx, and paranasal sinuses with appreciation of the relationships of these spatially complex structures. In addition, this technique allows structural visualization with unconventional angles, perspectives, and locations not conventionally accessible. Although biopsies, cultures, and lavages routinely done with endoscopy cannot be performed with VE, this technique holds promise for improving the diagnostic evaluation of the nasal cavity, the nasopharynx, and the paranasal sinuses. The unconventional visual perspectives and very low morbidity may complement many applications of simple diagnostic endoscopy.

Endoscopy↗
PubMed1996

Three-dimensional spiral CT cholangiography in patients with suspected obstructive biliary disease: comparison with endoscopic retrograde cholangiography.

PURPOSE: To evaluate the diagnostic potential of spiral computed tomography (CT) performed after the administration of cholangiographic contrast material (spiral CT cholangiography) in patients with suspected obstructive biliary disease. MATERIALS AND METHODS: After infusion of meglumine iodoxamate, 29 patients underwent upper abdominal spiral CT with subsequent three-dimensional rendering of the biliary tract. In 27 patients, the presence, site, and extent of biliary obstruction were compared with that at endoscopic retrograde cholangiography (ERC). RESULTS: Spiral CT cholangiography correctly depicted biliary obstruction in 14 of 27 patients, with no false-positive or false-negative cases. In one patient, the precise length of a common bile duct stenosis could not be assessed with spiral CT cholangiography. ERC demonstrated intrahepatic ductal stenoses more clearly in two patients. In two patients with hilar cholangiocarcinomas, spiral CT cholangiography depicted undrained areas not seen with ERC. CONCLUSION: Spiral CT cholangiography allows accurate assessment of the biliary system in patients with suspected obstructive biliary disease.

Adult↗
PubMed1996

Perspective volume rendering of CT and MR images: applications for endoscopic imaging.

PURPOSE: To use perspective volume rendering (PVR) of computed tomographic (CT) and magnetic resonance (MR) imaging data sets to simulate endoscopic views of human organ systems. MATERIALS AND METHODS: Perspective views of helical CT and MR images were reconstructed from the data, and tissues were classified by assigning color and opacity based on their CT attenuation or MR signal intensity. "Flight paths" were constructed through anatomic regions by defining key views along a spline path. Twelve movies of the thoracic aorta (n=3), tracheobronchial tree (n=4), colon (n=3), paranasal sinuses (n=1), and shoulder joint (n=1) were generated to display images along the flight path. All abnormal results were confirmed at surgery. RESULTS: PVR fly-through enabled evaluation of the full range of tissue densities, signal intensities, and their three-dimensional spatial relationships. CONCLUSION: PVR is a novel way to present volumetric data and may enable noninvasive diagnostic endoscopy and provide an alternate method to analyze volumetric imaging data for primary diagnosis.

Aorta, Thoracic↗
PubMed1995

The use of recombinant human erythropoietin in lung transplantation.

Recombinant human erythropoietin (r-HuEPO) was administered in 4 lung transplant recipients to treat chronic anemia beyond the immediate postoperative period. There were 2 males and 2 females with a mean age of 38 years (range 22-49). None of the patients had major infection or rejection problems, and no blood products were used. Because of different individual responses duration of therapy was 1 to 17 weeks (median 5) with a total dosage ranging from 8 to 36 x 10(3) IU (mean 21 x 10(3)). The median single dose was 58 IU/kg (range 36-100). Hemoglobin levels increased significantly from 9.1 +/- 0.2 to 12.7 +/- 0.3 g/dl (mean +/- SE; p < 0.01). There were no side effects. r-HuEPO is recommended in treatment of chronic anemia in lung transplant patients to save blood products and to exclude the potential risk of transfusion-transmitted viral infections.

Adult↗
PubMed1993

Closed circuit perfusion of an isolated rabbit lung. A new model for the evaluation of preservation quality of stored lungs.

The comparison of different preservation methods in lung transplantation demands a well standardized and reproducible animal model. The aim of this study was to establish as in vitro model in which the oxygenation capacity of the lung can be investigated over an extended period of time. Heart-lung blocks from 6 New Zealand white rabbits were harvested, the pulmonary artery and the left ventricle cannulated and the lungs perfused with whole rabbit blood by means of a roller pump and ventilated with room air. A dialyser was installed into the closed circuit perfusion for continuous deoxygenation of the oxygen-saturated blood gained from the left ventricle. Throughout the stable perfusion period the average arterial and venous partial oxygen pressure (pO2) levels were 105.8 +/- 15.5 mmHg and 55.2 +/- 6.2, respectively (P < 0.05). The average peak airway pressure steadily increased from 10.7 +/- 1.2 mmHg at the start of reperfusion to 21 +/- 14.4 mmHg after 180 minutes (P = NS). With this experimental setting it is possible to maintain stable conditions (i.e. constant venous and arterial blood gases) for at least 180 minutes. It is therefore feasible to compare the influences of different preservation methods on the quality of lung function.

Animals↗
PubMed1993

Early experience with sequential bilateral lung transplantation.

We performed 20 sequential bilateral lung transplantation in 19 consecutive patients from April 1990 to May 1992. Perioperative mortality was low (2 patients). One-year actuarial survival was 70%. All survivors had normal blood oxygen tension (82 mm Hg, mean) while breathing room air and continuing improvement of pulmonary function. Bronchial dehiscence did not occur. Stents were implanted in 7 patients to control bronchial stenosis. Aggressive treatment of graft rejection has been effective in preventing obliterative bronchiolitis.

Bronchial Diseases↗
PubMedDate not supplied

A new flush solution for extended lung preservation.

BACKGROUND: The aim of this study was to compare the effect of the most frequently used clinical preservation solution (Euro-Collins, group I) with a newly composed low potassium, glucose- and insulin-containing preservation solution (141 mmol/L sodium, 6.4 mmol/L potassium, 119 mmol/L chloride, 5 mmol/L magnesium, 10 gm/L glucose, 10 gm/L dextrane and 20 U/L insulin) (group II) on postischemic lung function. METHODS: We studied 12 isolated New Zealand White rabbit lungs in a closed circuit model during the first 4 hours of reperfusion after 24 hours of ischemic hypothermic storage. RESULTS: Oxygenation capacity, defined by the difference between the arterial and venous oxygen tension was significantly higher in group II compared with group I after 10 (58.7 +/- 5.8 versus 34.9 +/- 7.5 mm Hg), 30 (63.5 +/- 7.8 versus 27.3 +/- 10.4 mm Hg) and 180 minutes (77.7 +/- 7.2 versus 8.8 +/- 5.6 mm Hg). Ventilatory pressure was significantly lower in group II after 1 minute (11.3 +/- 1.3 mm Hg versus 13.7 +/- 0.5 mm Hg, p < 0.05), with no significant difference thereafter. No significant difference was found in pulmonary vascular resistance except after 20 minutes (30.8 +/- 1.2 dyns/cm5 [group I] versus 27.1 +/- 1.1 dyns/cm5 [group II], p < 0.05). CONCLUSION: These data suggest that this new solution provides superior lung function after 24 hours ischemic time compared with Euro-Collins solution.

Animals↗