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W Gross-Fengels

Publications and source records attributed to W Gross-Fengels.

At least 19 recordsLinked to original sources
PubMed2002

[PACS: from project to reality. Report of experiences on full digitalisation of the radiology department of a major hospital].

OBJECTIVE: To assess the time needed and the resulting effects of a complete digitalisation of a radiological department of a major hospital (856 beds, 28,000 in-patients, 35,000 out-patients/year) a pilot study was performed. This had to be done without interrupting routine services. RESULTS: After intensive preparations were performed and the hospital-network was completed, within a two year period all radiological functions (mammography excluded), reporting stations and archives were changed to a complete digital workflow. All modalities (provided by 3 different companies) are now connected by DICOM-work lists. The picture-files (4 GB/day) are automatically routed to the work-stations (n = 10), where the reporting and file shows are performed, to the digital archive and to the peripheral viewing-stations (n = 44). The distribution of the digital pictures takes place all over the hospital including the ORs and special units. We accomplished, to connect electronically the report and the image data. The clinical file shows are also performed completely digitally. The access to the data of the deep archive is possible by the dept. of radiology without any manual interaction. The film consumption was reduced to an amount of less than 10%, as compared to the prior PACS situation. Since PACS has been introduced the radiological productivity increased by more than 15% and throughput-time was clearly reduced. CONCLUSIONS: The complete digitalisation increases productivity and attractiveness of a hospital-radiology and helps to shorten diagnostic and therapeutic decision-making. The transfer from a conventional to a digital workflow is possible without interrupting the clinical services. Extensive preparations and ongoing assistance of such projects though are clearly needed.

Computer Systems↗
PubMed2002

[Injury of polyester grafts by vascular clamps].

UNLABELLED: Protected vascular clamps are not new. Clamp associated damage of human arteries has already been published over 20 years ago. The necessity of protective clamps seems to have been forgotten. In our explant archive (230 explants) we have observed an accumulation of graft ruptures in the groin (13 of 25 ruptures). We presume a multifactorial process. Clamp damage could be part of it. The aim of this study is to prove the clamp induced damage of polyester vascular grafts and to examine whether protected clamps can reduce this. METHOD: Five unprotected (Aesculap(R) FB512R, FB502, FB517, Ulrich CC1235, CV3535) and 5 protected vascular clamp types (Aesculap(R) FB667, FB668, Edwards(R) - formally Baxter(R) - Fogarty(R) CV5050, CV5201, Edwards(R) Cosgrove(R) CV1033) were tested. A longitudinal burst test was performed after maximal clamp closure on 6 different, multifilament polyester yarns of 2 different vascular grafts manufacturers (B. Braun(R), Edwards(R)). RESULTS: The yarn tests with protected clamps showed no difference to those of the unclamped yarns. After clamping with unprotected vascular clamps the stress-strain-diagrams differed significantly. The mean, maximum burst strength was up to 75 % lower. Video documentation revealed filament ruptures. Damage of the yarn surface was seen on a simple woven graft in scanning electron microscopy (SEM). DISCUSSION: The application of unprotected vascular clamps on polyester vascular grafts is common in Germany (56 %). The observed damage of multifilament polyester yarns makes it necessary to re-consider the use of unprotected vascular clamps. The benefit for biological vessels has already been shown.

Blood Vessel Prosthesis↗
PubMed2001

[Clinical value of native and contrast enhanced MRI in staging prostatic carcinoma before planned radical prostatectomy].

PURPOSE: To assess the clinical value of MRI with and without contrast agent in the staging of prostatic carcinoma. Relevance for surgical management. METHODS: 60 patients with carcinoma proven by biopsy or suspected prostatic carcinoma were evaluated with MRI. The examinations were performed in a 1.5 T (Philips ACS-NT Gyroscan) imager with multiplanar orientations before and after intravenous application of 0.1 mmol/kg/bw Gadodiamide (Omniscan-Nycomed/Amersham). The gold standard was histology after radical prostatectomy and in case of non-operability the consensual final staging. RESULTS: Compared to histology MRI revealed a sensitivity of 75% and a specificity of 82% in the differentiation of locally advanced carcinoma (T 3/4). Including the non-surgical cases MRI showed a sensitivity of 82.5% and a specificity of 86%. Interindividual analysis showed no difference in diagnostic accuracy between the non-enhanced and the contrast-enhanced techniques. In 23% of cases (n = 14) MRI induced changes in patient management. CONCLUSIONS: MRI is an accurate procedure in the local staging of prostatic carcinoma. In combination with clinical findings, PSA, and grading scores MRI has a significant influence on treatment selection. Contrast agent administration does not seem to increase the diagnostic accuracy significantly.

Aged↗
PubMed2000

[Stent wire fractures and mesh loosening in explanted endovascular prosthesis].

UNLABELLED: Vascular grafts are available since the middle of the 50's. Explant retrieval studies still reveal not published material degradation today, after over 40 years of product development. Endovascular grafts exist since the beginning of the 90's. New developments and modifications have lead to numerous devices. The importance of explant retrieval studies grows. MATERIALS AND METHODS: Among 33 stentgrafts, retrieved 5 to 43 months after implantation, the majority were 18 MinTec devices (17 Stentor, 1 Cragg). These 18 explants were examined by endoscopy, stereomicroscopy and scanning electron microscopy. RESULTS: The following material degradation was observed. The textile coating showed holes along the longitudinal seam, the ligatures in-between the stentframes burst, allowing the frames to dislocate. Occasional fractures of the stent wire were seen accompanied by bowl-shaped alterations of the surface. CONCLUSION: The Stentor device is, since its modification 1996, not available any longer. It was one of the most applied devices world-wide. The possible material deficiencies must be known by those performing patient follow-up. The occurrence of alterations within 43 months shows the importance of a continued follow-up besides clinical trials.

Device Removal↗
PubMed1998

Semiclosed iliac recanalisation by an inguinal approach--modified surgical techniques integrating interventional procedures.

OBJECTIVES: Technical success and early outcome of modified surgical techniques integrating interventional procedures for iliac recanalisation performed through an incision in the groin. MATERIALS: Sixty-one consecutive iliac arteries in 59 patients with long occlusions in 16, occlusions of the common iliac in 11, occlusions of the external iliac in 24 and multiple stenoses of the iliac in 10 cases underwent semiclosed recanalisation through a groin incision. METHODS: Passage of the lesion by guidewire permits retrograde ring-stripper endarterectomy over the wire as a guiding splint or thrombectomy with a double lumen balloon catheter. Residual lesions are corrected by balloon or stent angioplasty. Adequate outflow is established by femoral patch plasty. RESULTS: Conversion to a standard operation was required in 10 limbs (failure to recanalise the lesion in nine, rupture after angioplasty in one). Initial technical success was achieved in the remaining 51 limbs (recanalisation by ring stripper endarterectomy in 36, thrombectomy in 14, both in six, additional intraoperative angioplasty in 42). Five postoperative thromboses were successfully treated by a combined surgical and interventional approach accounting for a 1-month 100% secondary patency. CONCLUSION: Iliac recanalisation through the groin by modified ring stripper endarterectomy or modified thrombectomy in combination with intraoperative angioplasty is a safe and effective procedure. Long-term results are required to evaluate the procedure.

Adult↗
PubMed1998

[The possibilities and risks of outpatient PTA in patients with peripheral arterial obstructive disease].

PURPOSE: To evaluate risk and feasibility of outpatient PTA in patients with iliac-femoral artery disease we conducted a prospective study. MATERIAL AND METHOD: Out of a total group of 263 patients we selected 100 p. (38%) according to pre-defined criteria. The following criteria and others excluded the patients from outpatient procedures: insulin-dependent diabetes, poorly controlled hypertension, cardiac failure grade III and IV, chronic haemodialysis, severe overweight, elective stent implants. RESULTS: 90 of 100 patients for whom we had planned an outpatient procedure, could leave the day-clinic after a maximum of 10 hours of observation. For 10 patients we changed the procedure to an inpatient stay because of prolonged heparinisation, sudden elevation of arterial pressure, secondary stent implants and the need for local fibrinolysis therapy. Complications showed a trend to be lower in the outpatient group than in the inpatient group (2.0% vs 4.3%). CONCLUSIONS: Performing iliac-femoral PTA on an outpatient basis demands strict selection criteria and a close tie-up to a day clinic. In 2/3 of our patients we preferred to perform PTA on an inpatient basis. A higher incidence of risks was seen in the inpatient group.

Adult↗
PubMed1997

[Radiology information systems: improved performance evaluation, economics and quality assurance?].

By means of complete service control and standardized accounting processes, radiological information systems clearly contribute to improved results. They provide the prerequisites for the establishment of expanded networks and allow comparisons with comparable institutions. The quality of patient care can be improved since, for example, the production time from referral to finished result becomes shorter. Direct access to patient and findings data from several positions is possible. Preliminary results can be viewed immediately. The patient's history is accessible to authorized users at all times. The exact reproducibility and assignment of services leads to more clarity. By means of the information available form RIS, rapid adaptive processes can be undertaken. The system assists the to fulfill the requirements of health regulations. The above-mentioned relationships demonstrate that the EDP systems are well accepted by physicians, medical assistants, and administrators and represent an indispensable aid for solving problems.

Cost-Benefit Analysis↗
PubMed1996

[Popliteal aneurysms--surgical management versus conservative procedure].

217 patients with 349 popliteal aneurysms (PA) were studied. 45% presented with symptomatic complications, mainly thrombosis (21% acute, 15% chronic) and embolisation (7%). The mean diameter was significantly larger in acutely thrombosed (2.69 cm) than in patent PA (2.15 cm). The amputation rate in patients requiring emergency treatment was 36.1% after 2 years. The difference to patients undergoing bypass surgery in an asymptomatic stage (4-year graft patency 89%, limb salvage 100%) is highly significant. Of 128 PA treated conservatively, 53% were free of complications after 5 years. We conclude that prophylactic surgery of PA is justified in cases at high risk of developing complications, but that characteristics of those cases are not yet well defined.

Aged↗
PubMed1993

[An aneurysm of the portal vein].

Portal vein aneurysms are rare. We describe a patient with an aneurysmal dilatation (3 x 4.5 cm) of the right portal vein. Real-time ultrasonography revealed an anechoic lesion communicating with the portal vein, suggesting a portal vein aneurysm. Colour Doppler, contrast-enhanced computed tomography, and portal venography confirmed the diagnosis. No evidence of portal hypertension was found. Follow-up examinations did not reveal a significant change in the size of the aneurysm after 18 months.

Adult↗
PubMed1992

[Conventional x-ray techniques and computed tomography in the diagnosis of mediastinal lymph node involvement in non-small cell bronchogenic cancer. Which method is reliable?].

52 patients with bronchogenic carcinoma were studied preoperatively by means of conventional tomography and CT. The results were compared with surgical findings to evaluate the accuracy of these methods in detecting mediastinal lymph node involvement. 323 mediastinal lymph nodes were identified by CT and 237 of these were studied histologically. In 25% of lymph nodes with diameter between 0.5 and 1 cm metastases could be identified. On the other hand, 25% of lymph nodes measuring up to 3 cm did not contain metastases. The results varied in different regions (pre- and paratracheal, azygos region, aorto-pulmonary, subcarinal). The probability of involvement of small nodes was doubled if there were in regions neighbouring metastases. In view of the high incidence of false positive and false negative CT findings, conventional methods were sufficient in the presence of definite pathological findings.

Aged↗
PubMed1992

[Intracranial aneurysms. A comparison between magnetic resonance tomography and arteriography].

42 MRI of 36 patients with cerebral aneurysms were analysed retrospectively and compared with selective angiography. 92% of aneurysms proven by angiography were also detected by MRI. The smallest and surgically confirmed aneurysms had a diameter of 2-3 mm on MRI. 3 aneurysms were only demonstrated by selective angiography (8%). This concerned 5 mm sized aneurysms located at the anterior communicating artery (2) and middle cerebral artery (1). On the other hand 2 thrombosed aneurysms were only delineated by MRI (6%). Because partial thrombosis could not be demonstrated by angiography extensions of aneurysms were underestimated in 44% (n = 16) angiographically. A 2.5 cm sized lobulated aneurysm of the internal carotid artery was initially evaluated by MRI as being thrombosed subtotally, due to flow-phenomena. Angiography though showed a wide perfused lumen without visible thrombosis. A progressive thrombosis of a mycotic aneurysm of the internal carotid artery was shown by MRI during septic thrombosis of the cavernous sinus. In this case the number of angiographic controls could be reduced by use of MRI. Nevertheless, MRI was not able to substitute selective angiography, especially to exclude under 6 mm sized cerebral aneurysms. MRI could not demonstrate clearly the vessels in the neighbourhood of saccular aneurysms preoperatively.

Adult↗
PubMed1992

[Ergotism and ischemia of the limbs].

Clinical ergotism as seen today results almost exclusively from the intake of ergotamine tartrate in the treatment of migraine headache. Vasospasm of peripheral arteries is the leading clinical picture. Besides the formation of collaterals and a secondary thrombosis, the vasospasm is one of the specific findings in arteriography. Early diagnosis and withdrawal of the medication makes complete restitution possible. In all other cases intraarterial or intravenous infusion of sodium nitroprusside has turned out to be the most effective therapy. Balloon dilatation or operative intervention are an alternative therapy in those cases, where amputation of the limbs seems to be necessary.

Adult↗
PubMed1992

[Liver angiography--technique, indications and significance in focal liver processes].

Retrospective analysis of 155 liver angiographies and the literature data was carried out to appraise the current relevance of liver angiography in digital subtraction technique (i.a. DSA) for diagnosis of focal liver changes. A focal liver lesion was detected by angiography in 58 out of the 80 patients (72.5%) we investigated with a confirmed hepatic space occupation; an angiography correlate of the tumour type diagnosed was shown in 41 out of 69 (59.4%) of malignancies confirmed by surgery or biopsy histology; in the benign lesions, the angiographic diagnosis was consistent with the histological result in five out of six cases. DSA is thus usually clearly inferior to the tomographic sonography, CT and MRI in detection and qualification of the tumour type. However, it is still indispensable for planning operations or chemoembolization and for exact imaging of the portal perfusion conditions because of the frequent vascular anomalies in the anatomy of the liver.

Adenoma, Bile Duct↗
PubMed1992

[Complications in the kidney pelvis and the ureter following kidney transplantation].

Development of complications of the pelvis and the ureter, especially obstruction and necrosis with an urinary fistula was seen in 35 of 751 patients after kidney transplantation (4.6%). In this study they occurred significantly often in patients with multiple renal arteries of the donor kidney, for example pole arteries. An arterial angiography of the aorta abdominalis in living donors before transplantation is not be neglected. The diagnosis of urological complications includes sonography, in cases of ureteral obstruction percutaneous antegrade urography, and in a given case computed tomography.

Constriction, Pathologic↗