Renal Pseudoaneurysms and Arteriovenous Fistulas as a Complication of Nephron-Sparing Partial Nephrectomy: Technical and Functional Outcomes of Patients Treated With Selective Microcoil Embolization During a Ten-Year Period.

PURPOSE: The aim of this study was to evaluate the clinical and functional outcomes in patients who underwent selective interventional embolization of renal pseudoaneurysms or arteriovenous fistulas at our center. MATERIALS AND METHODS: Our retrospective analysis included all consecutive patients who received selective transcatheter embolization of renal pseudoaneurysms or arteriovenous fistulas after partial nephrectomy in our department from January, 2003 to September, 2013. The technical and clinical success rate and functional outcome of every procedure was collected and analyzed. Furthermore, the change in renal parenchymal volume before and after embolization was determined in a subgroup. RESULTS: A total of 1425 patients underwent partial nephrectomy at our hospital. Of these, 39 (2.7 %) were identified with a pseudoaneurysm or an arteriovenous fistula after partial nephrectomy. The diagnosis of the vascular lesions was made by means of biphasic CT or CEUS. Technical success by means of selective microcoil embolization was achieved in all 39 patients (100 %). Clinical success, defined as no need for further operation or nephrectomy during follow-up, was achieved in 35 of 39 patients (85.7 %). Renal function, as measured by eGFR before and after the intervention, did not change significantly. However, a mean loss of parenchymal volume of 25.2 % was observed in a subgroup. No major or minor complications were attributable to the embolization procedure. CONCLUSION: Transcatheter embolization is a promising method for treating vascular complications which may occur after partial nephrectomy. We confirm the high success rate of this technique while discussing renal functional outcomes and potential safety aspects. KEY POINTS: Arterial pseudoaneurysms and arteriovenous fistulas are rare but severe complications after partial nephrectomy. Selective microcoil embolization is a safe and effective kidney-preserving procedure for treating these complications. Embolization leads to a significant loss of renal parenchymal volume but not to a loss of renal function.

[C-arm CT-guided 3D navigation of percutaneous interventions]. / C-Bogen-CT-unterstützte 3D-Navigation perkutaner Interventionen.

So far C-arm CT images were predominantly used for a precise guidance of an endovascular or intra-arterial therapy. A novel combined 3D-navigation C-arm system now also allows cross-sectional and fluoroscopy controlled interventions. Studies have reported about successful CT-image guided navigation with C-arm systems in vertebroplasty. Insertion of the radiofrequency ablation probe is also conceivable for lung and liver tumors that had been labelled with lipiodol. In the future C-arm CT based navigation systems will probably allow simplified and safer complex interventions and simultaneously reduce radiation exposure.

[64-year old patient with tachycardia and signs of heart failure]. / 64-jähriger Patient mit Herzrasen und Zeichen einer Herzinsuffizienz.

We report on a 64-year old patient with known Morbus Osler and high cardiac output failure due to distinct arterio-venous malformations of the liver. Since the patient suffered from severe right heart insufficiency despite optimized medical therapy, we decided to conduct an interventional occlusion of the hepatic shunts in three single sessions. The transient elevation of transaminases was reversible. After interventional therapy cardiac output decreased from 20 l/min to 15 l/min (25%) leading to a reduction of diuretic dosage and a sustained stabilization of the clinical condition.

Intraoperative monitoring of intraarterial paraganglioma embolization by indocyaningreen fluorescence angiography.

Preoperative arterial embolization (AE) of paraganglioma (PG) is widely used to diminish intraoperative blood loss. Thereby conditions for a resection of the tumor shall be improved and risks for facial, vagal or hypoglossus nerve injuries are reduced. The vascularization of jugular and tympanic PGs is particularly complex due to collaterals with the vertebral and internal carotid arteries. Thus AE is often not complete and intraoperative blood loss may still be considerable. The postinterventional perfusion is of interest for the surgeon. We evaluated the arterial perfusion after AE using indocyaningreen (ICG) angiography. Six patients with PG, two carotid PGs, two jugular PGs, one vagal PG and one tympanic PG underwent surgery 1 day after AE. After tumor was exposed, ICG was intravenously applied followed by fluorescence angiography. Residual perfusion was assessed on the video clip and the perfusion index was automatically calculated by the IC-CALC software. This index was compared with the radiologist's assessment of arteriographic control after AE. Two of the six patients showed only marginal residual perfusion. These were patients with carotid PGs. The patient with the vagal PG showed 20%, the patients with jugular PGs 80 and 60% and the patient with the tympanic PG had 70% residual blood flow. The preoperative AE is rarely complete in PGs of the petrous bone. Intraoperative fluorescence angiography is a reliable procedure to evaluate the efficiency of preoperative embolization and can help the surgeon to estimate intraoperative bleeding favouring risks.

[Value of vascular ultrasound in the evaluation of hemodialysis fistulas]. / Formen und Komplikationen des Hämodialyseshunts - Stellenwert der Sonographie.

Vascular ultrasound has been proven to be effective in the assessment of hemodialysis fistulas providing noninvasive diagnostic work-up of vascular morphology and hemodynamics. The most common reason for hemodialysis fistula failure is thrombosis due to stenosis. Therefore, early identification of stenosis is essential to avoid complications. Ultrasound-based identification of hypoechoic plaques and intimal proliferation helps to reach therapeutic decisions. An estimation of the grade of stenosis is also feasible. An occlusion rate of up to 45% due to reduced blood flow justifies follow-up examinations. Due to frequent puncture of the fistula the risk of hemodynamically relevant stenoses is increased. Establishment of new ultrasound methods like B-flow and advanced dynamic flow (ADF) enable direct visualization of the flow in the area of the anastomosis. In addition, high-resolution ultrasound techniques allow improved flow detection without aliasing. Our report addresses the topics of examination strategy, possible complications, and treatment like percutaneous intervention techniques.

[Facet blockade, peridural and periradicular pain therapy]. / Facettenblockade, peridurale und periradikuläre Schmerztherapie.

More than 80% of vertebrogenic lumbar pain is unspecific and can only be attributed to a specific anatomic structure with difficulty. The pain can emanate from the intervertebral discs, intervertebral and sacroiliac (SI) joints, musculature, and ligaments. In a maximum of 7% of cases, the pain is radicular (4% due to intervertebral discs and 3% caused by stenoses). In 7-15% of cases, the pain's origin is located in the region of the vertebral joints and in up to 15% in the region of the SI joint. Although the overwhelming majority of pain has no clear structural cause, infiltrations of medications and nerve blockades are frequently employed. The efficacy of these procedures has however not been verified in controlled studies with the exception of epidural injection of corticosteroids for radicular pain. Epidural and epiradicular application of corticosteroids appear to be effective for radicular pain, at least on a short-term basis, although controlled studies have yielded controversial results. The difficulty lies partly in the exact placement at the affected root for applying the medication. This is hardly possible with a caudal injection, while with a lumbar peridural injection and periradicular injections it is only possible under X-ray control or even better CT guidance.

[Imaging of neuroendocrine tumors of the pancreas]. / Bildgebung bei neuroendokrinen Tumoren des Pankreas.

OBJECTIVE: To compare the value of the various imaging modalities in the detection of pancreatic islet cell tumors. METHODS: Analysis of the literature to compare the value of ultrasound, CT, MRI, angiography, venous sampling, scintigraphy and PET in the detection of neuroendocrine tumors of the pancreas. RESULTS: For transabdominal ultrasound a sensitivity of 60% has been reported; for endoscopic ultrasound a sensitivity of more than 90%. MRI with a sensitivity of 75-100% is more sensitive compared to CT with a sensitivity of 64-82%. Angiography and venous sampling have a reported sensitivity of 66% and 76%. Somatostatin receptor scintigraphy has a sensitivity of 81-88% with significant differences between the various histological subtypes of the pancreatic islet cell tumors. PET does not play an important role in the detection of neuroendocrine tumors of the pancreas. CONCLUSION: None of the various modalities is superior alone, so that it is often necessary to combine them for diagnostic imaging of pancreatic islet cell tumors.

[New abdominal CT angiography protocol on a 16 detector-row CT scanner - first results]. / Hochaufgelöste abdominelle Ubersichtsangiographie mit einem 16-Detektorzeilen-CT-System Erste Erfahrungen.

PURPOSE: Purpose of this study was the implementation of a new abdominal CT angiography protocol on a 16 detector-row CT scanner and the comparison to selective catheter angiography. METHODS: 76 patients with various vascular disorders underwent abdominal CT angiography on a recently developed 16 detector-row CT scanner using submillimeter slice collimation (16 x 0.75 mm). Results were compared with mesenteric and/or hepatic angiography in 17 patients performed during tumor embolization. Opacification was provided using individually tailored contrast application with a test bolus setting. To evaluate the contrast injection protocol density measurements within the vessel lumen were performed. RESULTS: Diagnostic image quality was achieved in all patients with angiographic comparison (n = 17). Within the hepatic and mesenteric vasculature up to 4th generation vessels could be identified. Compared to selective angiography CT angiography provided equivalent morphologic information up to the detectable vessel generation. With the applied contrast application regimen there were no significant differences in vessel enhancement along the abdominal aorta and iliac arteries. CONCLUSION: 16 detector-row CT enables whole abdominal angiographic studies with submillimeter resolution in a single breath-hold. The improved spatial resolution enables for high quality 3D visualization. Compared to invasive angiography, 16 detector-row CT reveals equivalent morphologic information.

Transjugular intrahepatic portosystemic shunting is not superior to endoscopic variceal band ligation for prevention of variceal rebleeding in cirrhotic patients: a randomized, controlled trial.

BACKGROUND: The aim of the present study was to compare the transjugular intrahepatic portosystemic shunt (TIPS) with variceal band ligation (VBL) in the prophylaxis of variceal rebleeding in patients with cirrhosis of the liver. METHODS: Fifty-four cirrhotic patients (21 Child-Pugh class A, 27 class B, 6 class C) were randomized to TIPS (n = 28) or VBL (n = 26) within 2 months after control of esophageal variceal hemorrhage. Statistical analysis was performed on the intention-to-treat principle. RESULTS: Mean follow-up was 2 years. Mortality risk at 1 and 2 years of follow-up was 7.8% +/- 5.3% and 19.9% +/- 8.8% in the TIPS group and 16.5% +/- 7.6% and 16.5% +/- 7.6% in the VBL group, respectively (n.s.); actuarial probability of remaining free from rebleeding was 83.7% +/- 77.4% and 71.4% +/- 10.4% in the TIPS group and 83.9% +/- 7.3% and 78.1% +/- 8.8% in the VBL group at 1 and 2 years, respectively (n.s.). Hepatic encephalopathy within 1 month after randomization was observed in 2 patients in the TIPS group and in 1 in the VBL group. CONCLUSION: TIPS is not superior to VBL in the prevention of variceal rebleeding. Furthermore, similar mortality rates in patients treated with TIPS or VBL negate TIPS as the preferred strategy for prevention of variceal rebleeding.

Case-oriented computer-based-training in radiology: concept, implementation and evaluation.

BACKGROUND: Providing high-quality clinical cases is important for teaching radiology. We developed, implemented and evaluated a program for a university hospital to support this task. METHODS: The system was built with Intranet technology and connected to the Picture Archiving and Communications System (PACS). It contains cases for every user group from students to attendants and is structured according to the ACR-code (American College of Radiology) 2. Each department member was given an individual account, could gather his teaching cases and put the completed cases into the common database. RESULTS: During 18 months 583 cases containing 4136 images involving all radiological techniques were compiled and 350 cases put into the common case repository. Workflow integration as well as individual interest influenced the personal efforts to participate but an increasing number of cases and minor modifications of the program improved user acceptance continuously. 101 students went through an evaluation which showed a high level of acceptance and a special interest in elaborate documentation. CONCLUSION: Electronic access to reference cases for all department members anytime anywhere is feasible. Critical success factors are workflow integration, reliability, efficient retrieval strategies and incentives for case authoring.

[TIPS in patients with therapy refractory ascites and kidney dysfunction]. / TIPS bei Patienten mit therapierefraktärem Aszites und Nierenfunktionsstörungen.

BACKGROUND: A transjugular intrahepatic portosystemic shunt (TIPS) is increasingly being used for treatment of patients with refractory ascites and renal failure. The aim of this study was to investigate the effects of TIPS in patients with refractory ascites and organic or functional renal impairment. METHODS: A TIPS was placed for refractory or intractable ascites in 10 consecutive patients with liver cirrhosis and impaired renal function (serum creatinine > 1.5 mg/100 ml). Four of them had organic kidney disorders. The other six patients had functional renal impairment due to the underlying liver disease. RESULTS: TIPS was effective in reducing ascites in 8 of 10 patients, including all patients with organic renal disease. Furthermore, after TIPS the renal function improved in all patients. Serum creatinine and serum urea levels decreased significantly from 1.8 to 1.5 mg/100 ml (p < 0.05) and from 107 to 78 mg/100 ml respectively. CONCLUSION: TIPS may be useful in patients with functional and in patients with organic renal disease, resulting in improvement of ascites and renal function.

Phase I and pharmacokinetic study of hepatic arterial infusion with oxaliplatin in combination with folinic acid and 5-fluorouracil in patients with hepatic metastases from colorectal cancer.

BACKGROUND: To determine dose-limiting toxicity (DLT), maximum tolerated dose (MTD), and pharmacokinetics (PK) of oxaliplatin administered as hepatic arterial infusion. PATIENTS AND METHODS: Patients with isolated hepatic metastases from colorectal cancer were treated every three weeks with increasing doses of oxaliplatin (4 hours; starting dose 25 mg/m2, escalation in steps of 25 mg/m2) in combination with folinic acid (1 hour, 200 mg/m2) and 5-fluorouracil (2 hour, 600 mg/m2). RESULTS: Twenty-one patients (median age, 61 years) have been entered all of whom are fully evaluable. The DLT has been observed at dose level 6, i.e., at 150 mg/m2/cycle and consisted of leucopenia, obliteration of the hepatic artery, and acute pancreatitis. Overall, toxicity mainly consisted of nausea/vomiting (16 of 21 patients), anemia (16 of 21), upper abdominal pain (15 of 21), sensory neuropathy (10 of 21), diarrhea (9 of 21), and thrombocytopenia (9 of 21). The mean PK parameters were: terminal half-life of ultrafiltrable platin, 17.75 +/- 9.29 hours; renal elimination, 48.7% +/- 14.1% of the applied dose; renal clearance 135.55 +/- 45.32 ml/min. The mean area under the plasma-concentration curve (AUC) increased linearly from 3.22 +/- 0.61 microg x h/ml to 18.45 +/- 8.90 microg x h/ml through the first five dose levels (P = 0.0004). Ten of eighteen evaluable patients achieved a complete or partial response (59%). CONCLUSIONS: The recommended dose for phase II studies is 125 mg/m2 oxaliplatin.

[Time needs in evaluating digital thoracic images on the monitor in comparison with alternator]. / Zeitbedarf bei der Befundung digitaler Thoraxaufnahmen am Monitor im Vergleich zum Alternator.

PURPOSE: Evaluation of time efficiency in softcopy reading versus hardcopy reading of digital chest x-rays. MATERIAL AND METHODS: 130 normal and pathologic chest x-rays in two plains were analyzed by 4 experienced radiologist at both a digital workstation and the light box. Reading time and switch time between two patient folders were measured as well as the frequency of post-processing at the monitor. RESULTS: Reading time at the workstation slightly exceeded reading time at the light box; differences were not statistically significant. Post-processing (frequency between 2% and 83%) did not significantly prolong reading time. Mean switch time between two patient folders was 4.3 sec at the workstation and 13.7 sec at the light box. CONCLUSION: As compared to hardcopy reading, softcopy reading of digital chest x-rays does not significantly increase reading time. Switch time between patient folders can be reduced at the workstation by a factor of two to four.

Interventional radiological procedures in impaired function of surgically implanted catheter-port systems.

PURPOSE: System-related complications in surgically implanted catheter-port systems (CPS) for intraarterial (i.a.) chemotherapy are well known. In most cases of complications, the treatment must be interrupted and the catheter-port system must be repaired surgically. We describe microinvasive interventional radiological procedures to correct some dysfunctions of CPS. METHODS: Five patients with repetitive dysfunction of CPS were treated with interventional techniques. Two patients presented with perfusion impairment, one patient had a pseudoaneurysm of the hepatic artery, and two patients presented with catheter displacement. Radiological interventions included mechanical recanalization with a guidewire, vascular stenting, and correction of catheter dislocation with a goose-neck snare. RESULTS: In all cases, correct function of the CPS was restored. No intervention-related complications occurred and surgery was avoided. Chemotherapy could be continued for a period of 4--10 months. CONCLUSION: For some system-related complications, minimally invasive radiological interventions can be used to restore the function of CPS for i.a. chemotherapy.

[Reconstructive endovascular treatment procedures in the area of the a. subclavia and its branches]. / Rekonstruktive endovaskuläre Behandlungsverfahren im Bereich der A. subclavia und ihrer Aste.

PURPOSE: Principles, methods and results of percutaneous therapy in acute and chronic vascular alterations of the subclavian artery and its branches. MATERIAL AND METHODS: 17 arteries in 15 patients have been treated. The patients suffered from stenoses (n = 6), occlusions (n = 7), aneurysms, (n = 2) or acute hemorrhage (n = 2). The lesions were located in the subclavian artery (n = 8), the axillary artery (n = 4) or the vertebral artery (n = 5). In all cases the procedures were performed via via a transfemoral approach. Balloon angioplasty was employed in 13 cases, in 6 cases bare stents and in 4 cases grafted stents were implanted. In one case additionally local lysis was performed. RESULTS: Primary technical success was achieved in all cases. No catheter complications did occur. In 13 Patients complete follow-up examinations could be performed. The life-threatening acute hemorrhages were stopped without recurrent bleeding. The aneurysms could be completely excluded without endoleaks. In 4 Patients of the stenosis-group re-stenosis occurred and following stent-implantation one occlusion after 6 months was observed. 8 patients are without clinical symptoms since the intervention. CONCLUSION: Stenotic and occlusive vascular alterations as well as aneurysms and the acute hemorrhage in supraaortic arteries can be effectively and safely treated by endovascular techniques using percutaneous groin access.

Dynamic contrast-enhanced MR angiography from the distal aorta to the ankle joint with a step-by-step technique.

OBJECTIVE: The aim of this study was to visualize the arteries from the distal aorta to the ankle joint and to determine the accuracy of MR angiography for detecting stenoses and occlusions. SUBJECTS AND METHODS: Twenty-four patients with peripheral arterial occlusive disease underwent digital subtraction angiography and were examined on a 1.5-T MR scanner. The transit time for contrast material was determined with a test bolus injection. A T1-weighted three-dimensional gradient-echo sequence with short TR and TE was used for a dynamic measurement at the level of the iliac arteries, the upper leg, and the lower leg arteries. For each level a single dose of gadolinium was injected into an antecubital vein with an MR power injector. Maximal-intensity-projection reconstructions were calculated after subtraction of the first measurement at each level. Two experienced MR radiologists who were unaware of the digital subtraction angiography results interactively evaluated both the MIP reconstructions and the single slices on a workstation, first independently and then in a consensus interpretation. RESULTS: With digital subtraction angiography, 80 hemodynamically significant stenoses and 39 occlusions were detected. For the stenoses and occlusions, a sensitivity of 100% was found for MR angiography. The specificity for the assessment of stenoses and occlusions was 98% and 94%, respectively, for the iliac arteries; 98% and 94%, respectively, for the upper leg arteries; and 94% and 95%, respectively, for the lower leg arteries. Most false-positive findings of occlusion were due to metal stents present in the iliac (n = 3) and upper leg (n = 4) arteries. CONCLUSION: The MR imaging technique that we used revealed the arteries from the distal aorta to the ankle and proved to be reliable at showing arterial stenoses and occlusions.

Transjugular intrahepatic portosystemic shunt for cirrhosis and ascites: Effects in patients with organic or functional renal failure.

BACKGROUND: A transjugular intrahepatic portosystemic shunt (TIPS) is increasingly being used for treatment of patients with refractory ascites and functional renal failure. In contrast, organic renal disease is commonly considered a relative contraindication for TIPS placement. The aim of this pilot study was to investigate the effects of TIPS in patients with refractory ascites and organic or functional renal impairment. METHODS: A TIPS was placed for refractory or intractable ascites in 10 consecutive patients with liver cirrhosis and impaired renal function (serum creatinine > 1.5 mg/100 ml). Four of them had organic kidney disorders. Of these patients, three had moderate renal impairment, and one had end-stage renal disease and needed hemodialysis every other day. The other six patients had functional renal impairment due to the underlying liver disease. RESULTS: TIPS was effective in reducing ascites in 8 of 10 patients, including all patients with organic renal disease. Furthermore, after TIPS the renal function improved in all patients. Serum creatinine and serum urea levels decreased significantly from 1.8 +/- 0.1 to 1.5 +/- 0.1 mg/100 ml (P < 0.05) and from 107 +/- 13 to 78 +/- 14 mg/100 ml (P < 0.05), respectively. The renal function of the three patients with organic renal failure improved similarly, as observed in the six patients with functional renal failure. In the patient on hemodialysis, TIPS was effective in reducing the frequency of paracenteses. CONCLUSION: TIPS may be useful in patients with functional and in patients with organic renal disease, resulting in improvement of ascites and renal function.

Successful treatment of chronic Budd-Chiari syndrome with a transjugular intrahepatic portosystemic shunt.

Budd-Chiari syndrome is characterized by obstruction of the hepatic venous outflow tract. Therapeutic options for chronic Budd-Chiari syndrome are limited. We report the case of a 28-year-old woman who presented with recurrence of chronic Budd-Chiari syndrome with total obstruction of all major hepatic veins. Due to worsening liver function over the course of 1 year, she had to be listed for liver transplantation. Because of therapy-refractory ascites, declining renal function and severe esophageal varices, a transjugular intrahepatic portosystemic shunt (TIPS) was placed, planned as a bridge to transplantation. Following TIPS, a marked recovery of liver function could be observed, accompanied by disappearance of ascites, esophageal varices, and normalization of kidney function. Therefore, the patient could be removed from the waiting list for liver transplantation. This case demonstrates for the first time that the use of TIPS in chronic Budd-Chiari syndrome may result in marked recovery of liver function.

Hepatic arterial infusion with oxaliplatin, folinic acid, and 5-fluorouracil in patients with hepatic metastases from colorectal cancer: role of carcino-embryonic antigen in assessment of response.

BACKGROUND: Therapy for patients with hepatic metastases from colorectal cancer (CRC) remains controversial and may be improved by regional oxaliplatin which proved to be effective when administered systemically to patients with advanced CRC. METHODS: During the current study, which aims to determine the maximum tolerated dose, the dose-limiting toxicity, and the pharmacokinetics of oxaliplatin applied as hepatic intra-arterial infusion combined with folinic acid and 5-fluorouracil in patients with hepatic metastases from CRC, serial levels of carcino-embryonic antigen were determined and their relationship to response to therapy was assessed. RESULTS: Toxicity mainly consisted of nausea, pain, mucositis, sensorial neuropathy, diarrhoea, and thrombocytopenia. The results of tumor marker analyses suggest that progressive disease may be detected early by increasing CEA levels and responsive disease may be characterized by low or decreasing values. CONCLUSIONS: Further analyses are warranted to determine the role of CEA in the assessment of response as compared to imaging techniques.