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U Fink

Publications and source records attributed to U Fink.

At least 73 records · Page 4Linked to original sources
PubMed1997

Prognostic importance of histomorphologic subclassification for epithelial thymic tumors.

BACKGROUND: The prognostic importance of various clinical variables (age, sex, association with myasthenia gravis), staging according to Masaoka, histologic type according to the Marino/Kirchner/Müller-Hermelink (MKM-H) classification, and residual tumor category (R category) was evaluated in a retrospective analysis. METHODS: Eighty-two patients with epithelial thymic tumors (ETTs) treated in the period 1969-1993 were evaluated, and archived specimens were histologically reclassified according to the classification of MKM-H. RESULTS: Age, sex, and association with myasthenia gravis were of no prognostic importance. The R category is of significant prognostic importance, with 5- and 10-year survival rates of 93.6% and 87.3%, respectively, for R0 resections compared with 0% at 5 years for R1 and R2 resections (p < 0.001). Staging (Masaoka) proved to be a prognostic factor (5-/10-year survival: stage I, 100%/90.9%; II, 95%/88.2%; III, 55.9%/46.6%; and IV, 10.8%/ 10.8%; p < 0.001). Histologic typing according to MKM-H is also of significant prognostic importance (5/10 year survival: thymomas: medullary, 100%/100%; mixed, 100%/100%, predominantly cortical, 68.6%/68.6%; cortical, 65.8%/65.8%; thymic carcinomas: well-differentiated type, 62.3%/44.5%; thymic carcinomas other than well-differentiated type, 33.6%/26.9%; p < 0.001). Multivariate analysis demonstrated that staging (p < 0.001), R category (p < 0.026), and MKM-H classification (p < 0.028) have an independent impact on survival. CONCLUSIONS: Staging (Masaoka), R category, and histologic classification (MKM-H) are important independent prognostic factors for patients with epithelial thymic tumors. Complete (R0) surgical resections should be the ultimate goal in the clinical management of patients with epithelial thymic tumors.

Adult↗
PubMed1997

[Safety aspects in the coating of titanium slide components].

Due to the ever increasing percentage of patients who suffer from allergies and need joint replacements, it is necessary to also consider using titanium for the bearing surface. Hence, the number of coated titanium bearing surfaces for both hips and knees is increasing. It is difficult for the user to evaluate the products already marketed. This paper describes the presently used coating techniques without considering sophisticated technical details but listing the advantages and disadvantages of the various technologies. Using the list of necessary basic investigations for qualifying a coating together with production relevant measures for quality assurance, this paper aims to provide the possibility to get involved with a supplier in a discussion about the suitability of the coated titanium bearing components without regarding the specific technical details.

Alloys↗
PubMed1997

Spiral CT angiography and 3D reconstruction in patients with aortic coarctation.

The objective of this study was to assess the reliability of spiral CT angiography (CTA) and 3D reconstruction in patients with aortic coarctation (CoA). Eighteen patients with suspected or surgically proven coarctation were examined by spiral CT. In addition to the axial slices, 3D reconstructions, such as shaded surface display (SSD) and maximum intensity projection (MIP), were used to determine the diameters of the CoA and the pre- and poststenotic aorta and to visualise the collateral vessels. Diameters derived from cardiac catheterization were compared with those from CTA in 8 patients. The degree of aortic stenosis was correlated with blood pressure gradients (BPG) in 12 patients. The difference between the diameters of the CoA and the pre- and poststenotic aorta derived from MIP and angiography was not statistically significant (p = 0.69). With SSD the internal thoracic artery was detected in 16 and the posterior intercostal artery in 13 cases. The degree of aortic stenosis correlated poorly with the BPG (r = 0.51, r2 = 0.26). CTA with 3D reconstruction represents a reliable noninvasive technique for the assessment of the degree of CoA and the visualisation of collateral vessels. It may serve as a follow-up investigation after intervention or surgical treatment.

Adolescent↗
PubMed1997

Gastric Cancer.

Explore the source record for details and available documents.

Antineoplastic Agents↗
PubMed1997

[A report on experience with a second-generation PACS installation in routine computed tomographic operations].

PURPOSE: Our institute has been using a pilot SIENET-PACS system for the last five years; its advantages and disadvantages in daily use are described. MATERIAL AND METHODS: The SIENET system connects 2 CT, 3 MRT and 2 angiographic installations with 7 viewing consoles and with an optical archive. From January 1994 to 1997 approximately 19,000 patients were examined by CT and the results stored digitally in the PACS system. RESULTS: A representative analysis of selected patient data revealed problems in 12.8% of patients with regard to the radiological information system and also the hospital information system. While the digital data proved satisfactory, the production of digital images was excellent but time-consuming. The image archive was reliable but required greater capacity for our purposes. CONCLUSIONS: Manual retrieval of patient data presented problems and integration of the radiology information system and PADS is essential. Digital data gathering is an advantage. Digital imaging is too slow and should be improved by more suitable software. Integration of new archival storage methods and compatibility with the DICOM standard is, judging form our experience, essential.

Angiography, Digital Subtraction↗
PubMed1997

[Spiral CT angiography in demonstration of cerebral aneurysms before and after treatment with titanium clips].

PURPOSE: To determine the suitability of spiral CT angiography (SCTA) in patients with intracerebral titanium aneurysm clips. MATERIAL AND METHOD: The section parameters were optimised using a phantom. 16 patients were examined preoperatively and 18 following treatment of aneurysms with clips. RESULTS: The resolution, sensitivity and specificity for demonstrating cerebral aneurysms measuring > or = 3 mm was 91.3% and 75% respectively. In 15 patients with intracerebral clips there were no or only minor artefacts; three examinations were of no value because of major metal artefacts. Amongst six aneurysms demonstrated angiographically, two, which measured more than 3 mm, could be shown by SCTA. CONCLUSION: SCTA was able to demonstrate intracerebral aneurysms measuring > or = 3 mm. Titanium clips did not usually affect image quality significantly.

Adolescent↗
PubMed1997

Postoperative spiral computed tomography and magnetic resonance angiography after aneurysm clipping with titanium clips.

OBJECTIVE: To reduce morbidity and mortality after subarachnoid hemorrhage, it is imperative to evaluate the results of the surgical treatment of cerebral aneurysms. We investigated the usefulness of spiral computed tomography (CT) and magnetic resonance angiography as postoperative control examinations after cerebral aneurysms were clipped with titanium clips. METHODS: Eleven patients with 13 treated aneurysms were studied prospectively with postoperative digital subtraction angiography, spiral CT, and magnetic resonance angiography. The occlusion of the dome of the aneurysm, the presence of a remnant of the neck, the patency of the parent vessels and other major vessels, and the presence of vasospasm were investigated. RESULTS: The different parameters could all be well evaluated by postoperative spiral CT. The artifacts caused by the titanium clips, although relatively small compared with artifacts from other clips, precluded evaluating the dome and the neck of the aneurysm with magnetic resonance angiography. CONCLUSION: In our opinion, spiral CT promises to become a valuable aid in in the postoperative evaluation of clipped aneurysms, and we recommend its routine performance. Postoperative digital subtraction angiography remains the gold standard and has to be performed when spiral CT reveals abnormalities, when the neck of the aneurysm cannot be evaluated because the clip overlays it, or when, intraoperatively, imperfect clipping is suspected and intraoperative angiography cannot be performed.

Adolescent↗
PubMed1997

Aneurysm clips made of titanium: magnetic characteristics and artifacts in MR.

PURPOSE: To evaluate the magnetic characteristics, artifact formation, and implant safety of titanium aneurysm clips for use in MR imaging. METHODS: Aneurysm clips made of titanium alloy TiAl6V4 were tested in a magnetometer to determine their magnetic susceptibility and in a 1.5-T MR imager using both a geometric phantom and an animal model. A commercially available alpha-Phynox clip served as the reference standard. RESULTS: We found minimal magnetization and a significant reduction in image artifacts with the titanium clip as compared with the Phynox clip. CONCLUSION: The titanium clips improve image quality, biocompatibility, and patient safety in medical MR applications.

Aneurysm↗
PubMed1996

Identification of characteristics for malignancy of solitary pulmonary nodules using high-resolution computed tomography.

The aim of this prospective study was to apply the described single pathological appearance and possibilities of differentiating signs from other studies and summarize them concerning their differential diagnostic importance to improve differential diagnostic strategies concerning the dignity of solitary pulmonary nodules. 55 consecutive patients with solitary pulmonary nodules were examinated using high-resolution computed tomography (HRCT) before surgery. Thereafter HRCT-diagnosis was proven by histological assessment. Only lesions which were removed by surgery were used. No lesion was excluded by size. Necrotic areas, cavitation, satellite lesions and circumscribed pleural thickening were only found in the malignant nodules. Discrimination between benign and malignant lesions was possible by: mean diameter (P<.01), mean density (P<.01) and air inclusion (P<.05), by air bronchogram/bronchiologram (P<.05), indistinct/fogged (P<.05) and dystelectatic (P<.01) margin, the presence (P<.01) and length (P<.01) of spiculae, spiculae extended into the pleura visceralis (P<.05) and pleural distension (P<.01). A single sign can be seen in either benign or malignant nodules, but if considered together with other signs it may have a different meaning. HRCT can enable a differentiation of BSPN from MSPN in the majority of cases. As imaging methods could not get a nearly complete certainty about the dignity the chance of survival of patients could be preserved exclusively by an early surgery.

Carcinoma↗
PubMed1996

Preoperative chemotherapy in gastric cancer.

Even with extended surgery, including systematic lymphadenectomy of the lymph node compartment II, only half of the patients with locally advanced gastric cancer (LAGC)-which comprises stages IIIA, IIIB, and IV-undergo macroscopic and microscopic tumor-free resection (i.e., R0 resection, according to UICC 1987/AICC 1988). An improvement in this situation is best accomplished by preoperative treatment modalities to increase the R0 resection rate and by preoperative and postoperative treatment to reduce local recurrences and distant metastases. For LAGC, which includes approximately two thirds of patients with locoregionally confined tumors, preoperative chemotherapy (CTx) represents a promising approach. Among a group of patients with surgically or clinically staged unresectable LAGC, approximately half underwent R0 resection after downstaging induced by active CTx. The long-term survival of these patients seems to be improved. Even in patients who had primarily unresectable tumors as defined by explorative laparotomy, the long-term survival was about 20% after preoperative CTx and subsequent surgery. Based on these experiences, randomized trials investigating preoperative CTx versus surgery alone are clearly needed to define whether such an approach has an impact on RO resection rates and survival of patients with LAGC. Preconditions for such trials are clinical staging procedures, including endoscopic ultrasonography (T category) and surgical laparoscopy plus lavage (excluding peritoneal carcinomatosis), and a standardized surgical procedure.

Combined Modality Therapy↗
PubMed1996

Locally advanced rectal cancer: resection and intraoperative radiotherapy using the flab method combined with preoperative or postoperative radiochemotherapy.

PURPOSE: Surgery often fails to achieve local control in advanced rectal cancer. Additional measures are necessary to prevent local recurrence. The aim of this study was to evaluate intraoperative radiation therapy (IORT) (flab technique) combined with preoperative or postoperative radiochemotherapy. PATIENTS/METHODS: IORT is performed using a flexible flab containing hollow plastic tubes that are connected to a multichannel afterloading device with a 370 Gbq-192-Ir source. Patients receive an intraoperative dose of 15 Gy. Target volumes were measured in a cadaver experiment. From 1989 to 1993, 38 patients were included in this study. Nineteen patients were staged as T3 tumors by preoperative endosonography (Group I) and 19 as T4 tumors (Group II). Patients in Group I underwent resection (abdominoperineal resection (APR), 16; anterior resection, 3) and IORT, followed by postoperative radiochemotherapy (50 Gy/5-fluorouracil), whereas patients in Group II received preoperative radiochemotherapy (40 Gy/5-fluorouracil) followed by resection (APR, 18; anterior resection, 1) and IORT. Mean follow-up was 25.5 months. RESULTS: Operative radicality in Group I was RO (13), R1 (3), and R2 (3), and in Group II it was RO (14), R1 (3), R2 (2). R2 resections were attributable to preoperative undetected distant metastases. Perioperative mortality was 0 percent in Group I and 10.5 percent (n = 2) in Group II. Postoperative morbidity was 53 percent (n = 10) in Group I and 84 percent (n = 16) in Group II with delayed sacral wound healing being the predominant problem. Stenosis of the ureter occurred in two patients (Group II). Late or persistent therapy-related complications were seen in two patients in Group I and in six patients in Group II. Local recurrence developed in three patients in Group I (15.8 percent) and in two patients in Group II (10.5 percent). Survival data do not reach statistical significance between the two groups because of small numbers but show a favorable trend for the preoperative radiochemotherapy group. When compared with a matched historical control group of patients receiving resection only, adjuvant/neoadjuvant radiotherapy with resection/IORT improves survival significantly. CONCLUSION: The flab method is a simple but especially practical technique for IORT in the pelvis. Adjuvant/neoadjuvant therapy combined with resection/IORT is associated with high morbidity but acceptable mortality. Preliminary survival data are encouraging and call for a controlled prospective randomized trial.

Antimetabolites, Antineoplastic↗
PubMed1996

[A method of computer-assisted, 3-dimensional subtraction angiography using spiral roentgen computerized tomography].

The objective of this study was to develop a method for 3D subtraction CT angiography and to optimize the visualization after semi-automatic segmentation. Ten patients with aneurysms of the abdominal aorta were examined using spiral CT. To reconstruct the vessels, as well as adjacent organs such as the liver and kidneys, one image data volume was acquired before and after injection of the contrast agent. The CT scans were obtained with a Siemens Somatom Plus 4. To improve the results of automatic segmentation, as well as visualization by maximum intensity projection (i.e. removal of bony structures), subtraction of both image volumes is necessary. However, small translation shifts disturb the subtraction process and produce artificial contours. To calculate the disparities along the three coordinate axes of two corresponding image volumes, a cepstrum filter is applied to a pair of image volumes. After detection of the disparities, which manifest as bright spots, the real shift of the two subsignals can be calculated. Translation of the corresponding image volume pairs to their correct positions improves the subtraction process. In all cases the size of the aneurysm and the abdominal organs could be better segmented and visualized. Application of the cepstrum filter and subtraction of the image volumes before and after contrast medium injection completely removes the bony structures in the image data and results in superior visualization results.

Angiography, Digital Subtraction↗
PubMed1996

[Differentiation of solitary pulmonary coin lesions by high-resolution computerized tomography].

PURPOSE: The aim of this prospective study was not to describe individual morphological findings in benign and malignant solitary intrapulmonary nodules; it was instead to examine in a critical manner the indications for differentiation found in the literature in order to facilitate safe differential diagnosis of benign and malignant nodules. PATIENTS AND METHODS: A total of 64 solitary pulmonary nodules were examined with high-resolution computed tomography and correlated with histological findings. Only lesions that had been removed by surgery were used. No lesion was excluded on the grounds of size. RESULTS: Useful characteristics for the differentiation of benign from malignant pulmonary nodules were: diameter and density of the lesion, air inclusion, unsharp and dystelectatic margin, the presence of spicules, length of spicules, spicules extending to the visceral pleura, pleural tail sign and cirumscribed pleural thickening. CONCLUSION: For the differentiation of benign and malignant solitary pulmonary nodules meticulous assessment of the margin of the nodule is necessary. Using the criteria mentioned, a sensitivity of 85% and a specifity of 78% can be achieved for the identification of malignant pulmonary nodules. Since it was not possible to differentiate between benign and malignant nodules with certainty using imaging methods, the chance of patient survival could only be promoted by early surgery.

Adult↗
PubMed1996

Adenocarcinoma of the gastro-esophageal junction: CT for monitoring during neoadjuvant chemotherapy.

OBJECTIVE: A clinical study was performed to assess the diagnostic value of spiral CT for evaluation of response during neoadjuvant chemotherapy (CTx) in patients with adenocarcinoma of the gastro-esophageal-junction (GEJ). Results were compared to those of endoscopy. METHODS AND MATERIAL: Twenty-five patients with histologically proven adenocarcinoma of the GEJ scheduled to undergo neoadjuvant CTx were studied. Before CT examination, 1200 ml of a vanilla flavoured paraffin emulsion were applied orally to the fasting patients and 40 mg BuscopanR or 2 mg glucagon were injected i.v. for hypotonia. Iodine (100 ml) was injected automatically (3 ml/s) and the CT scan was started 10 s after complete administration of CM. For response evaluation to CTx, four standardized parameters were measured by two experienced, blinded radiologists. The results were categorized according to the WHO classification of 1981 and compared to those of endoscopy. RESULTS: In 24 of 25 patients endoscopic and computed tomographic response evaluation showed a close correlation (r = 0.96). CONCLUSION: Spiral CT with negative oral contrast agent is a suitable technique for monitoring of GEJ masses. In combination with standardized metric parameters it offers a quantitative response evaluation in patients with GEJ masses during neoadjuvant CTx.

Adenocarcinoma↗
PubMed1996

Phase II study of gemcitabine in patients with advanced pancreatic cancer.

The efficacy and safety of gemcitabine at a starting dose of 800 mg m2 administered once a week for 3 weeks with 1 week's rest was investigated in chemonaive patients with advanced and/or metastatic pancreatic cancer. Of 34 patients, 32 were evaluable for efficacy, 20 patients had metastatic stage IV disease, 25 had a performance status of 1 and 26 (76%) patients has significant pain on presentation. All responses were independently validated by an external oncology review board: two patients achieved a partial response that lasted 5.8 and 5.2 months (6.3%) and six patients were stable for at least 4 weeks. The median duration of survival for evaluable patients was 6.3 months (range 1.6-19.2 months). The tumour markers, CEA, CA 19-9 and CA 195 were serially measured in 16 patients. There was a good correlation with tumour response when all three markers were significantly decreased. In 4 of 16 patients, tumour marker levels decreased by > or = 60%, including the two responders, one patient who survived for 12 months and one patient who showed objective tumour shrinkage but was deemed ineligible for response evaluation because the disease was considered not to be bidimensionally measurable. Symptomatic benefits included improvement in performance status (17.2%), analgesic requirement (7.4%), pain score (28.6%) and nausea (27.3%). The mean number of cycles administered was 2.5 and the mean dosage received was 890 mg m2 per injection. Seventy-four per cent of dose administrations were given on schedule. Toxicity, particularly haematological toxicity, reported as the maximum WHO grade experienced by patients was mild. Infective episodes were rare and limited to WHO grade 2 (6.7%). Nausea and vomiting was generally modest (WHO grade 3, 26.7%). Other side-effects included mild transient flu-like symptoms (seven patients) and peripheral oedema (three patients), which was not associated with abnormal cardiac hepatic or renal function. Gemcitabine has modest activity in pancreatic cancer, a limited positive improvement on a range of patient benefit parameters and has a mild toxicity profile. For these reasons and because of its novel mode of action, gemcitabine warrants further investigation in combination studies in pancreatic cancer.

Adult↗