[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.

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.

[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.

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.

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.

Liver intraarterial chemotherapy: use of the femoral artery for percutaneous implantation of catheter-port systems.

To provide intraarterial chemotherapy of the liver in 30 outpatients with colorectal cancer metastases and other malignancies, 32 catheter-port systems were implanted percutaneously via the femoral artery. Mean patency was 229 days. Percutaneous placement was feasible and safe. Compared with surgical placement, the overall complication rate (12%) was comparable or less.

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.

[Percutaneous implantation of port-catheter systems for intraarterial chemotherapy of the liver]. / Perkutane Implantation von Portsystemen in der Arteria hepatica.

PURPOSE: The objective of this study was to determine the usefulness, safety and acceptance of a new technique of percutaneous implantation of port-catheter-systems (PIPS) for locoregional intraarterial chemotherapy of the liver. MATERIAL AND METHODS: In 50 patients with malignant hepatic disease, 52 percutaneously implantable port-catheter systems were implanted for intraarterial chemotherapy of the liver as an interventional radiological technique. A commercially available angiographic catheter was placed in the hepatic artery under fluoroscopic control via a transfemoral approach and connected to a Port-A-Cath situated in the groin. This procedure was done on an outpatient basis; no medical treatment was administered. RESULTS: Percutaneous placement of the port-catheter system was successful in all cases, also in those with a hepatomesenteric trunk. No peri- and post-interventional complications occurred. The median patency was 312 days (13-547 days). The catheter-related complication rate was 12%. The function could be restored by replacement or an interventional procedure in all but one case (2%). Infection and leakage did not occur. The system had been withdrawn without complications in 7/52 cases for a variety of reasons (e.g. hemihepatectomy, desire of the patient or clinician, dissection after intervention, replacement). CONCLUSION: Percutaneous placement of a port-catheter system is a safe and easy alternative to the surgical placement of port systems for hepatic intraarterial chemotherapy. Long-term complication rates are comparable. The option of easy withdrawal and interventional correction of dysfunction as well as lower costs are additional advantages.

[Percutaneous interventional radiologic implantation of intravenous port-catheter systems]. / Interventionell-radiologische perkutane Implantation intravenöser Port-Katheter-Systeme.

PURPOSE: Percutaneous interventional radiologic and surgical techniques of port-catheter implantation are described and compared with regard to the technical procedure and results. MATERIALS AND METHODS: In 53 patients with various malignancies interventional radiologic implantation of port-catheter systems into the subclavian vein was performed to provide long-term intravenous access for chemotherapy. The technical procedure, operation time, complication rates and long-term patency were compared with those of surgically implanted systems. RESULTS: Implantation was successful in all cases. Mean operation time was 36 min (range 20-55 min). Mean function time was 189 days (range 7-518). Primary patency rate was 92.5% with a total complication rate of 15% (8/53). In three patients (5.7%) pneumothorax was observed but did not require further treatment. In two cases (3.8%) local infection occurred, and in one patient (1.8%) a non-complicated wound dehiscence. In 12/53 patients (22.6%) the system was withdrawn. Among these, withdrawal was due to complications in 4/53 (7.6%) cases. CONCLUSIONS: Interventional radiologic implantation of long-term intravenous port-catheter systems is comparable to surgical placement with regard to both complication rate and long-term patency.

[The percutaneous treatment of surgical and catheter-angiographic vascular complications]. / Perkutane Behandlung chirurgischer und katheterangiographischer Gefässkomplikationen.

PURPOSE: Technical innovations of angioplasty have introduced new therapeutic options in the treatment of symptomatic arteriosclerotic disease. Atherectomy devices, aspiration catheters and vascular endoprostheses can be used not only for angioplasty purpose but also for correction of iatrogenic dissections and thromboembolic complications. MATERIAL AND METHODS: 54 patients with vascular complications after surgical (n = 7) and percutaneous (n = 47) interventions were observed in a 5 years period. The complications included acute dissections in 34 cases, acute thrombosis in 4 cases, distal embolism after angioplasty in 14 cases, and two cases with arterial rupture after balloon dilatation. RESULTS: 34 patients with dissections and 18 patients with acute thrombosis were treated. Stent implantation for repair of vessel dissection was successful in 33 of 34 cases. Percutaneous catheter aspiration in combination with local thrombolysis was successful in 4 cases with local thrombosis. Distal emboli after angioplasty were successfully removed using aspiration catheters in 13 of 14 patients. Vessel rupture after angioplasty was closed with prolonged balloon dilatation in two patients avoiding emergency surgery. CONCLUSION: Using newly developed intravascular technologies such as atherectomy, stents, and catheter aspiration, many iatrogenic complications after vascular surgery or vascular interventions can be treated. These technologies should be available in every radiology department performing angioplasty.

[Reducing radiation dosage with modern DSA equipment]. / Einsparungen bei der Durchleuchtungsdosis durch moderne DSA-Anlagen.

PURPOSE: In angiographic and interventional procedures the often long fluoroscopy times add a great deal to the total patient dose. The new Multistar T.O.P. (Siemens) is equipped with various features for dose reduction. In this study pulsed fluoroscopy was tested versus standard continuous fluoroscopy and supervisions. MATERIALS AND METHODS: Fluoroscopy with 3, 7.5, and 15 pulses/s in the Multistar T.O.P. were compared to standard fluoroscopy and to reduced-dose supervision in a human pelvic phantom. The skin entry dose and pelvic dose were continuously registered. RESULTS: The supervision mode used 58% of the dose used in continuous fluoroscopy. Pulsed fluoroscopy with 15 pulses/s required 54%, 7.5 pulses/s 27% and 3 pulses/s. These provide adequate image quality with only 10% of the standard dose. CONCLUSIONS: It was possible to save up to 90% of the fluoroscopy dose in interventions and angiographies when using the new pulsed fluoromodes available in the Multistar T.O.P.