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Biomedical subjects

S Biesterfeld

Publications and source records attributed to S Biesterfeld.

At least 55 records · Page 3Linked to original sources
PubMed1995

Percutaneous balloon embolectomy with a self-expanding tulip sheath: in vivo experiments.

PURPOSE: To test a self-expanding tulip-shaped sheath designed for percutaneous embolectomy in an in vivo animal experiment. MATERIALS AND METHODS: In nine sheep, a total of 23 percutaneous balloon embolectomies were performed with use of a self-expanding tulip sheath device with an outer diameter of 9- or 10-F when collapsed. A 10-F instrument was used in 11 cases, and a 9-F instrument was used in 12. Radiopaque emboli were pushed into the aorta via the left carotid or contralateral femoral artery with a 16-F introducer sheath. RESULTS: The embolus was captured in the tulip cage in all 23 cases. Retrieval of the embolus into the sheath was complete in 21 of 23 cases. In two cases, minor parts of the embolus dislodged from the sheath. Major embolism did not occur. In nine cases, the outer sheath had to be cleared of remaining clot particles with aspiration. CONCLUSION: The noncovered self-expanding tulip sheath is an effective and safe instrument for percutaneous embolectomy under in vivo conditions.

Animals↗
PubMed1995

Acute massive pulmonary embolism: use of a rotatable pigtail catheter for diagnosis and fragmentation therapy.

PURPOSE: A modified pigtail catheter for angiographic documentation and mechanical fragmentation of pulmonary embolism was evaluated for its efficacy and safety. MATERIALS AND METHODS: Rotation of the 5-F pigtail catheter was performed with an electric drive or a handle. The wire left an oval side hole at the outer curvature and served as an axis of rotation. Fragmentation properties were assessed in vitro. Pulmonary positioning, steerability, rotation behavior, and safety were tested in six pigs. Pulmonary embolic occlusions were recanalized in eight dogs. RESULTS: The catheter system was promptly positioned and easily steered in the pulmonary arteries. On average, 53% of the occluded pulmonary arteries were recanalized. Recanalization reduced the emboli-induced elevation of the pulmonary artery mean pressure by 73%. Slight perivascular hemorrhage occurred in three dogs. CONCLUSION: Rapid partial recanalization was achieved with relative ease of instrumentation. The technique is an extension of the commonly performed pigtail catheterization of the pulmonary arteries, which may increase its clinical acceptance.

Animals↗
PubMed1995

[The diagnosis and fragmentation therapy of acute massive pulmonary embolism with a rotatable pigtail catheter: experimental studies].

PURPOSE: A dedicated pigtail catheter system which allows angiographic documentation and adjunctive mechanical fragmentation of pulmonary emboli was evaluated in an animal experiment. MATERIAL AND METHOD: The 5-F catheter provided with an oval side hole proximal to the pigtail tip was rotated manually or with an electric drive, and with the wire as a rotation axis. Pulmonary embolic occlusions were recanalized in ten dogs. Catheter positioning, monitoring, rotation behaviour, safety and fragmentation properties were assessed. RESULTS: The catheter system was rapidly positioned and easily monitored in the pulmonary arteries. On average, 55% (+/- 20%) of the embolic occlusions were recanalized. Embolus fragmentation reduced the emboli-induced increase of the pulmonary arterial mean pressure by 72%. In three dogs, histology revealed slight perivascular haemorrhage. CONCLUSION: Partial recanalisation of the pulmonary arteries was achieved rapidly with relative ease of instrumentation. Since fragmentation technique is an adjunct to the commonly performed pigtail catheterization of the pulmonary arteries, no special training is required.

Acute Disease↗
PubMed1994

Polyploidy in non-neoplastic tissues.

AIM: To investigate the prevalence and amount of polyploidy in fine needle aspiration specimens of the liver, urinary cytospin preparations, and cytospin preparations from pleural and peritoneal fluid. METHODS: Cells from 44 liver smears, 48 urine specimens, and 46 pleural and peritoneal aspirations were examined. After Feulgen restaining the DNA content of 100 randomly selected nuclei was determined using a TAS-plus image analysis system, combined with an automated microscope. RESULTS: Polyploidy was observed up to 16c in the liver, and up to 8c in urothelium and mesothelium. Sixty eight per cent of the liver aspirates contained polyploid nuclei. The rate in urothelium was 20.8% and in mesothelium 6.5%. CONCLUSIONS: Polyploidy in the liver may be interpreted as being associated with tissue differentiation, but the findings in urothelium and mesothelium remain of unknown importance.

Aged↗
PubMed1994

Influence of fixation and preparation on the AgNOR distribution in routinely processed breast cancer specimens.

AgNOR staining is mostly performed on unstained sections from paraffin-embedded material. This well-established application may be limited, if only a small biopsy or cytologic material is available. In this study, we analyzed the influence of different routine preparation types from histology and cytology on AgNOR staining results. 15 cases of ductal breast carcinoma were investigated using five different preparations per case: frozen sections, sections from formalin-fixed and paraffin-embedded, previously frozen material, sections from routinely formalin-fixed and paraffin-embedded fresh material, alcohol-fixed and air-dried cytological smears. After application of a modified combined Feulgen-AgNOR staining technique, AgNOR quantification on 150 nuclei per specimen was performed by TV-image analysis. For each preparation type adequate AgNOR staining results were obtained. Although there were a number of statistically significant correlations, the median values for the mean nuclear area, the mean number of AgNORs per cell, the mean AgNOR area per cell and the mean AgNOR sum area per cell were quite different within the 5 preparation types. This means that results, obtained with one preparation type, may not be taken as standard for a different one.

Adenocarcinoma, Mucinous↗
PubMed1993

DNA single cell cytometry in lymphocytic pleocytosis of the cerebrospinal fluid.

The value of DNA single-cell cytometry for the detection of neoplasia in Feulgen-stained cerebrospinal fluid cytological specimens was tested on 34 cases of Non-Hodgkin's lymphoma or leukemia and on 66 cases of viral or bacterial meningitis as a disease control group. The DNA content of 200 randomly chosen nuclei was measured on one pre-existing, cytologically representative slide per case, using a TV-image analysis system TAS-plus (Leitz, Germany). Neoplasia was diagnosed, if at least three nuclei with a DNA content above 5c (5cEE > or = 3) were found. The sensitivity investigating only one slide per case was 79.4% (27/34), the specificity 78.8% (52/66). Three lymphomas and 7 inflammatory cases were classified as suspicious (0 < 5cEE < 3). In 4 lymphoma cases (11.8%) a false-negative diagnosis and in 7 cases (10.6%) of viral meningitis a false-positive diagnosis were made. No false-positive diagnosis occurred in bacterial meningitis. While the false-negative diagnoses may be due to the only slightly increased number of cells in cerebrospinal fluid, no final explanation for increased DNA values after viral infection can be given. Therefore, before using DNA single-cell cytometry to prove the malignant character of lymphocytic pleocytosis in cerebrospinal fluid, viral meningitis has to be clinically excluded.

Adult↗
PubMed1992

Subsequently occurring leiomyosarcoma and desmoid tumor of the right thigh.

We present the case of a 44-year-old patient with a primary leiomyosarcoma of the right upper thigh, who developed a second mesenchymal lesion at the same thigh, diagnosed as an extra-abdominal desmoid tumor, some months after surgical treatment of his leiomyosarcoma. Clinically, histomorphologically, DNA cytometrically, immunohistochemically and radiologically the different histogenetic origin of the two lesions could be proven. The patient died 17 months after his first tumor diagnosis of lung metastases of his leiomyosarcoma.

Adult↗
PubMed1992

[Percutaneous CT-controlled cutting-needle biopsy of diffuse interstitial and alveolar lung diseases--the technic and results].

Twenty-three patients underwent CT-guided large-bore biopsy of diffuse lung disease of clinically and radiologically indeterminate etiology. The procedure was preceded by negative transbronchial biopsy in 20 cases. CT-guided biopsies were performed with a 14-gauge Trucut-needle. Obtaining at least 3 specimens of different parts of the diseased area, a correct histologic diagnosis was achieved in all cases. The size of the histologic specimens (mean: 5-6 mm) exceeded that of the specimens obtained by transbronchial biopsy as reported in the literature. Two major complications occurred and included a rapidly developing tension pneumothorax treated by a small-bore catheter and one self-limited hemoptysis. Major advantages of percutaneous CT-guided biopsy are the nonsuperimposed and very sensitive imaging of lung alterations in diffuse lung diseases that allows evidence of adjacent less and more involved areas accessible by one biopsy approach. CT-guided large-bore biopsy with a cutting needle seems to be a very promising, accurate method in the pathomorphologic work-up of diffuse lung diseases rendering open biopsy unnecessary in many cases.

Adult↗
PubMed1992

Prediction of recurrence in giant cell bone tumors by DNA cytometry.

The most interesting therapeutic aspect of giant cell bone tumors is which patients can be cured without a risk of recurrence by intralesional surgery (curettage). To find out the suitability of some DNA cytometric and morphometric parameters for showing differences between this group of patients (n = 9) and those with recurrence (n = 12), the parameters mean ploidy, 2cDI (mean square deviation of the tumor cell DNA content from the normal 2c value), mean nuclear area and its variability were calculated from cytologic specimens prepared by a cell separation technique from formalin-fixed, paraffin-embedded tissues, measuring the values of 100 stromal cells per case by a TV image analysis system. Further measurements were performed on 19 cases of different diseases of the bone and on an additional 17 cases of giant cell tumors without follow-up. The 2cDI allowed us to distinguish the two groups of patients, with and without recurrence, without overlap; even the lowest value for patients with recurrence was higher than the highest value for cured ones. Mean ploidy analysis resulted in a less convincing discrimination of the patients. Mean nuclear area and its variability failed to predict recurrence. Single-cell DNA cytometry provided a parameter, 2cDI, that was able to predict recurrence in patients with giant cell bone tumors with high sensitivity.

Adult↗
PubMed1992

[A hypervascular adrenal adenoma. A differential diagnostic problem in dynamic CT and MRT].

At dynamic CT, Gd-DTPA-enhanced MRI, and digital subtraction angiography, a large adrenal adenoma verified by resection histology presented as a hypervascular tumor. In all imaging modalities, it showed a strong patchy enhancement during the early phases of the passage of contrast media and subsequent intralesional contrast equilibration. This case demonstrates that even high enhancement does not rule out an adrenal adenoma with certainty. In the oncologic patient, therapeutic decisions should not be made on the basis of the contrast behavior of an adrenal lesion alone.

Adenoma↗
PubMed1991

DNA-cytometric detection of euploid polyploidization in oral lichen ruber planus.

The DNA distribution was analyzed in 29 cases of oral lichen ruber planus that were negative for human papillomavirus and not suspected of being precancerous. Monolayer smears prepared from formalin-fixed, paraffin-embedded tissues were automatically Feulgen stained and used for rapid interactive DNA cytometry via a TV-based image analysis system combined with an automated microscope. Nuclei with DNA contents greater than 4c were found in 25 cases (86%). DNA contents greater than 8c were seen in five cases (17%), and small peaks at 8c were found in three cases. These increased DNA values in nonprecancerous lesions must be interpreted as euploid polyploidization and have to be taken into account if DNA measurements are performed for diagnostic purposes in lichen ruber planus lesions that are suspected of having malignant transformation.

DNA↗
PubMed1991

[Adenomyomatosis of the gallbladder in CT].

The computed tomographic findings of adenomyomatosis of the gallbladder are described in nine patients, including all main types of this disease. Diagnosis was confirmed by typical cholecystographic findings in all cases, as well as by histological evaluation in three cases. Only in the fundal type were the intramural diverticula well visualized on CT. Although in the other types the Rokitansky-Aschoff sinuses were not clearly shown by CT, when performed without application of a cholegraphic agent, the computed tomographic findings nevertheless appeared to be characteristic. In the area involved, layering of the thickened gallbladder wall, associated with irregular ill-defined borders of the inner layer, appears to be typical. Visualization of these findings was improved following enhancement by intravenous contrast media.

Adult↗
PubMed1991

Quantitative pathological study of aggressiveness of giant cell tumor of bone.

Clinical behavior of giant cell tumor of bone (GCT) may vary remarkably from latent to very aggressive. Quantitative pathological methods were used to evaluate the aggressiveness of GCT. Fifteen cytometric parameters were measured and computed on routine sections of 40 GCTs which had been treated with curettage. The surgery factor (with or without additional procedures like bone cement packing or freezing after the curettage) was also taken into account and computed. Nineteen of the 40 GCTs were cured and 21 recurred. While no single one from the 15 parameters measured showed significant differences between the cured and recurrent groups according to the Mann-Whitney's U test or Student's t test, a 4-variable function was established with a stepwise discriminant analysis which could correctly identify 70.8% of the predicted cases as cured or recurrent (jackknife procedure). The function also suggested that in addition to the surgery factor, which no doubt had close relation with the prognosis, the most important risk factor in histological parameters was SA40, i.e. the percent of cells with nucleus larger than 40 square microns. Single cells extracted from paraffin-embedded blocks of 38 GCTs were analyzed by DNA-image cytometry. The 2c deviation index (2cDI) showed wide heterogeneity ranging from those consistent with benign tumors to those with apparent malignant ones, which may account for its diversity in clinical behaviour. Sixteen of the 38 cases had been treated with curettage, 8 of them were cured and followed up for at least 3 years and the remaining 8 recurred. The significant difference of 2cDI between the two groups suggested that these DNA parameters are useful in evaluating the aggressiveness of GCT for the selection of an adequate treatment. Quantitative approaches appeared to be more objective and more sensitive in evaluating the aggressiveness and predicting the prognosis of GCT than the subjective grading system used before.

Bone Neoplasms↗
PubMed1990

[Methodological requirements for precise measurements using DNA single cell cytometry].

Methodological aspects on DNA single cell cytometry were investigated. Specimens can be homogeneously Feulgen-stained if a high constancy of temperature is realized in the staining cuvette during acid hydrolysis. For the TV image analysis system under investigation (TAS-plus, Leitz) a linear correlation (r greater than 0.99) between physically defined optical transmission values and resulting electronic signals was found. Shading effects can be controlled by using a narrow mask width (VQ less than 1.5%). As an internal standard blood cells or epithelial cells can be used if a correction factor, that was found to be mainly constant, is calculated.

Cytodiagnosis↗
PubMed1990

Performance of a TV image analysis system as a microdensitometer.

The performance of a TV image analysis system combined with an automated microscope (the Leitz TAS plus) as a microdensitometer and morphometric device was investigated. There was a strict linear correlation (r greater than .99) between the physically defined optical transmission values and the resulting electronic signals from the plumbicon TV camera for the whole area displayed on the monitor. The shading of the optoelectronic system had a coefficient of variation (CV) of 1.42% for measurements in the center of the displayed area, but a CV of 3.55% for measurements over the whole monitor area. Densitometric measurements remained stable 15 minutes after putting the microscope lamp into operation (T less than 0.075%, remeasuring every two minutes). The geometric distortion, measured as different ferret diameters of ideally round latex particles, ranged from +/- 0.5% to +/- 1.0% deviation over the entire displayed area. These results indicate that densitometric and morphometric measurements with this equipment are sufficiently precise and reproducible when performed in the center of the area displayed on the monitor.

Densitometry↗
PubMed1989

Automated Feulgen staining with a temperature-controlled staining machine.

A Shandon Varistain 24-3 staining machine was modified in order to run automated DNA Feulgen staining. Initial studies showed a strict dependence of the staining intensity (integrated optical density [IOD]) on the temperature of the DNA hydrolysis in 4 N HCl: a difference of 0.5 degrees C around the optimum hydrolysis temperature of 27.5 degrees C resulted in IOD differences of up to 7.8% in epithelial cells and up to 12.0% in lymphocytes. A temperature-controlled stainless steel cuvette, covered with a 4 N HCl-resistant material, was developed and integrated into the machine. Temperature measurements were performed at different positions in the cuvette and on glass slides with copper-constantan electrodes fixed on them; no temperature gradient could be detected within the cuvette. The adjusted temperature of 27.5 degrees C remained constant over 24 hours. The coefficient of variation (CV) of the staining intensity in lymphocytes between different areas on the same slide and between different slides of the same staining cycle was less than 0.6%. The CV between different staining cycles was 5.9%. This system for automated Feulgen staining thus gives reproducible and reliable results and may be introduced into routine diagnostic procedures.

Coloring Agents↗