[First experiences with temporary vena cava filters]. / Erste Erfahrungen mit temporären Vena-cava-Filtern.

AIM: For prophylactic measures we used 3 different temporarily insertable vena cava filters. MATERIAL AND METHODS: In 49 patients we inserted 12 Cook-filters (6 transjugular, 6 transfemoral), 11 Angio-cor-filters (1 transjugular, 10 transbrachial), 26 Antheor-filters (1 transjugular, 1 transfemoral, 24 transbrachial). 35 patients underwent a lysis therapy, 11 a major operation of the pelvis, and 3 patients a Caesarean section. RESULTS: No patient suffered from a clinically significant pulmonary embolism after filter insertion, but complications occurred caused by the basic therapy (1 lethal abdominal aortic aneurysm operation, 1 cerebral bleeding, 2 retroperitoneal haematomas, 2 streptokinase fever reactions, 1 compartment syndrome, 1 macro-haematuria) or by therapy joined with the filters insertion (2 groin haematomas, 2 haematomas of the bend of the elbow, 2 subclavian vein thrombosis, 1 catheter dislocation, 1 infection, 1 air embolism, 1 break of a leg of the filter basket). CONCLUSION: Temporary vena cava filters are highly efficient in preventing pulmonary embolism, but the side-effects show that they should only be inserted in patients with known deep vein thrombosis and a high risk treatment of the underlying disease.

[Carbon dioxide as an alternative contrast medium in peripheral angiography]. / Kohlendioxid als alternatives Kontrastmittel für die periphere Angiographie.

A closed gas pressure pistol was used in 50 patient CO2 angiography as a supplementary method to conventional injection with liquid contrast medium. These were diagnostic pelvis-leg angiographies (n = 36), therapeutic angiographies (n = 8), haemodialysis fistulas (n = 3), suspected stenosis of a renal transplant artery (n = 1) and suspected renal artery stenosis (n = 1). 246 renal angiography series were performed with CO2. Dosages varied in accordance with the imaged vascular area between 10 ccm;(shunt imaging) and up to 100 cm3 (pelvis-leg angiography), at pressures between 400 mbar in case of haemodialysis fistulas up to 2000 mbar in the pelvis-leg area. Short-term feeling of fullness and even nausea were accompanying symptoms in 4 patients. The image quality was slightly inferior to that of conventional contrast medium images due to an elevated signal-to-noise ratio. Injector-monitored CO2 angiographies enabled imaging of the distal aorta or of peripheral vascular sections, imaging of the upper extremity and presentation of kidney transplants in patients with a relative or absolute contraindication to iodised contrast media.

Recognition and characterization of small colonic neoplasia with high-definition colonoscopy using i-Scan is as precise as chromoendoscopy.

BACKGROUND: The EPKi system (Pentax, Japan) enables resolution above HDTV. Aim of the study was to test the efficacy of HD+ alone and with the new post-processing digital filter i-Scan or chromoendoscopy (Methylene blue 0.1%) in screening for colorectal cancer. We focused on lesions less than 5 mm as a surrogate marker for the optical possibilities of the EPKi system. METHODS: The last 30 cm of the colon in a screening population were inspected with HD+ alone, in combination with i-Scan (2:1 randomisation) and subsequently with chromoendoscopy. All lesions were characterized and targeted biopsies were performed. RESULTS: i-Scan augmented in 69 patients the identification of lesions from 176 to 335 (p<0.001) and chromoendoscopy to 646 (p<0.001). The additional lesions were mainly flat (type IIb, 74%), which were only recognized using i-Scan or chromoendoscopy. The amount of neoplasias was not significantly different (HD+: 5, i-Scan: 11, Chromoendoscopy: 11), but all could correctly be predicted using i-Scan or chromoendoscopy. CONCLUSIONS: HD+ colonoscopy with and without i-Scan unmask a plethora of small lesions but chromoendoscopy can even advance the number. However, i-Scan was able to predict neoplasia as precisely as chromoendoscopy and might shortly replace chromoendoscopy as a more time efficient tool.

[CTA and MRA in peripheral arterial disease--is DSA out?]. / CTA und MRA bei PAVK--ist die DSA "out"?

New developments in technique and postprocessing have led to further improvement in diagnosing and evaluating peripheral arterial disease (PAD) by noninvasive computed tomographic angiography (CTA) and magnetic resonance angiography (MRA). Under clinical conditions diagnostic conventional angiography (DSA) will be increasingly replaced by CTA and MRA. The radiologist has to become familiar with the field of indications, the different techniques, postprocessing tools, and effective visualization. In consideration of the current literature some methodological aspects and the role of CTA and MRA in PAD will be discussed.

Central venous access ports placed by interventional radiologists: experience with 125 consecutive patients.

PURPOSE: To assess safety and function of central venous port systems implanted percutaneously in the interventional radiology suite. METHODS: One hundred and twenty-five consecutive ports in 123 patients were evaluated retrospectively. One hundred and twenty ports were implanted via the subclavian vein. RESULTS: Technical success was 100%. Fourteen patients (11.2%) experienced immediate procedural complications, all minor (pneumothorax 1.6%). During follow-up (4-343 days, mean service period 97.8 days), nine complications occurred, six of which were major. These were three port infections which led to hospitalization and port removal, one chamber penetration through the skin, and two port occlusions. Port removal as a result of complications was performed in six patients. Altogether, 20 complications occurred within a total of 11,056 days of service, which means 1.8 events per 1000 days of service. CONCLUSION: Percutaneous implantation of central venous port systems is safe and easy to perform. Complication rates of this study compare favorably with those of other radiological and surgical series.

[The angiography of kidney transplant arteries using carbon dioxide]. / Angiographie von Transplantatnierenarterien mit Kohlendioxid.

BACKGROUND AND OBJECTIVE: After renal transplantation hypertension occurs in 60-80% of patients, in 3-23% of them due to renal artery stenosis in the transplanted kidney. Angiographic assessment of the severity of the stenosis would best be done with a non-nephrotoxic contrast medium. We investigated the use of carbon dioxide, a bubble-forming contrast medium excreted via the lung, for its suitability in the angiography of the arterial system in the renal transplant. PATIENTS AND METHODS: In an uncontrolled series of observations on six patients with renal transplants and hypertension who were being treated with three or four antihypertensive drugs, the transplant's arteries were demonstrated with carbon dioxide, injected by Seldinger technique into the ipsilateral femoral artery, and the results recorded by subtraction angiography. RESULTS: The angiograms demonstrated postoperative kinked renal artery, a plaque in the external iliac artery, and a sharply angled origin of the external iliac artery in one case each, and three normal cases. CONCLUSIONS: Carbon dioxide is a suitable medium for demonstrating renal arteries in a transplanted kidney and is preferable to conventional contrast media for the angiographic diagnosis of possible renal artery stenosis.

[Perforated aneurysm of the left hepatic artery]. / Perforiertes Aneurysma der Arteria hepatica sinistra.

Aneurysms of the hepatic artery are second (20%) to the splenic artery the most common site of splanchnic artery aneurysms. The frequency of location in the branches of the hepatic artery is as follows: common hepatic 63%, right hepatic 28, left hepatic 5%, both left and right hepatic artery 4%. Today atherosclerosis (30 - 32%) is the most prevalent etiology, followed by trauma (22 - 28%) and inflammatory lesions (11%). The average age is 41,6 years, the male to female ratio 2:1. In 64-80% of patients rupture of the aneurysm is the first and dramatic clinical manifestation. The mortality is then about 35%. The case of a 64 years old female with perforated aneurysm of the left hepatic artery is presented and the literature is reviewed with emphasis on etiology, clinical manifestation, diagnostic and therapeutic (surgical and non-surgical) procedures.

Temporary vena cava filters and ultrahigh streptokinase thrombolysis therapy: a clinical study.

PURPOSE: To assess the efficacy of temporary vena cava filters in patients undergoing ultrahigh-dose streptokinase thrombolysis for iliocaval thrombosis and to determine therapy success and filter and therapy complications. METHODS: Forty-five patients were studied regarding extension and characteristics of thrombosis, duration, success, and complications of thrombolysis therapy, filter type, access route, pulmonary embolisms, and filter complications. RESULTS: Complete recanalization was achieved in 57% of cases. Filters were inserted predominantly via a transbrachial route. One fatal pulmonary embolism (2%) occurred 1 day after starting thrombolysis. No other pulmonary embolism was noted. Other complications were induced by thrombolysis alone (n = 12), thrombolysis and filter (n = 9), and filter alone (n = 11). CONCLUSION: Fatal pulmonary embolisms as a complication of ultrahigh-dose treatment of pelvic or caval thrombosis can not safely be prevented by the temporary vena cava filters currently available. Filter design needs to be improved.

[Indications and results of surgically treated, with temporary vena cava filter managed patients]. / Indikation und Ergebnisse bei operierten, mit temporären Vena-cava-Filtern versorgten Patienten.

Heavily injured patients, patients who underwent operations on pelvis, hips, abdomen or malignoma surgery, as well as gynaecology patients suffering from malignoma or previous deep femoral vein thrombosis in connection with pregnancy or obesity are at risk to suffer from pulmonary embolism with potentially lethal course. In a retrospective study we evaluated the advantage of the prophylactic use of temporary vena cava filters and their side effects. The indications were 18 cases of surgery, with known iliacal vein or cava thrombosis, 3 cases of pregnancy thromboses, and 1 high-dose heparinisation after acute pulmonary embolism without lysis. Additionally a postoperative lysis therapy was performed due to a life-threatening pulmonary embolism in 1 patient. 1 Cook filter (transfemoral), 3 Angiocor filters (transbrachial), and 19 Antheor filters (3 transjugular, 5 transfemoral, 11 transbrachial) were implanted. In these patients no clinically visible pulmonary embolism occurred under therapy, 3 thrombi were detected in the filter. Complications were caused either by the underlying therapy alone (1 lethal outcome of abdominal aortic aneurysm surgery), by the combination of therapy and cava filter implantation (1 case of arm haematoma, 1 ascending thrombosis) or by filter implantation alone (2 cases of v. subclavia thrombosis, 1 dislocation, 1 basket rupture). Since temporary cava filters have no secondary complications per se, their use seems justified as long as there is strict indication including presence of iliacal vein or cava thrombosis and risk of thrombi mobilisation.

[Doppler ultrasound monitoring during vascular interventions]. / Dopplerultraschallmonitoring während Gefässintervention.

Doppler ultrasound examination as diagnostic device in angiology yields only discontinuous information on flow velocities in vessels during insonation with hand-held probes. Continuous insonation and therefore determination of flow velocities in arteries are necessary to evaluate flow disturbances and changes of flow velocities during radiologic invasive interventions, i.e. implantation of stents, during percutaneous transluminal angioplasty therapy or local lysis. This modification of Doppler ultrasound examination is already used in neurosurgery for permanent monitoring of flow velocities in large brain vessels in one or both hemispheres during therapy. In our institute we developed a probe holder device to fix a miniature Doppler ultrasound probe (8-MHZ pulsed-wave probe) on the skin surface. Therefore continuous insonation during the manipulations is easy to realize. Information about complications such as occlusions, thrombi, emboli and changes in flow velocity is immediately present on the screen. We have monitored 40 patients during radiologic interventional therapy in arteries of the lower limb. Complications during the interventions were detected immediately and could be corrected.

Clinical experience with temporary vena caval filters.

PURPOSE: To look at the benefits and complications of different vena caval filters inserted prophylactically. Three temporarily implantable caval filter systems were used in 67 patients. MATERIALS AND METHODS: Twelve Cook filters (six transjugular, six transfemoral), 11 Angiocor filters (one transjugular, 10 transbrachial), and 44 Antheor filters (three transjugular, four transfemoral, 37 transbrachial) were successfully implanted. In known iliac vein or caval thrombosis, the prophylactic filters were placed during thrombolytic therapy in 46 cases, surgery in 17 cases, thrombosis in pregnancy in three cases, and high-dose heparinization without lysis in one case. RESULTS: One patient had a fatal pulmonary embolism during treatment; seven thrombi were detected in the filter. Other complications were caused either by the underlying therapy alone (one fatal outcome of abdominal aorta aneurysmal surgery, two cases of cerebral hemorrhage, two cases of retroperitoneal hematomas, two cases of streptokinase fever reactions, one compartment syndrome, two cases of macrohematuria), by the combination of therapy and caval filter implantation (three cases of groin hematomas, three cases of arm hematomas), or by filter implantation alone (two cases of subclavian vein thrombosis, one catheter infection, one dislocation, one air embolism, one basket rupture). The bleeding complications were related to the aggressive thrombolytic therapy and would have occurred without filter implantation. CONCLUSION: Because temporary caval filters have no long-term complications per se, their use seems sensible as long as there are stringent indications, including the presence of iliac vein or caval thrombosis and risk of thrombus mobilization. The Antheor filter system was the most convenient system for implantation.