[Image-guided pain therapy. Sympathicolysis]. / Bildgestützte Schmerztherapie. Sympathikolyse.

BACKGROUND: In the autonomic nerve system most sympathetic neurons synapse peripherally in the ganglia of the sympathetic trunk. A reduction in sympathicotonia by partial elimination of these ganglia is a therapeutic approach that has been used for more than 100 years. In the early 1920s the first attempts at percutaneous sympathicolysis (SL) were carried out. Nowadays, minimally invasive image-guided SL has become an integral part of interventional radiology. Established indications for SL are hyperhidrosis, critical limb ischemia and the complex regional pain syndrome. METHODS: The standard imaging guidance modality in SL is computed tomography (CT) which allows the exact placement of the puncture needle in the target area under visualization of the surrounding structures. Ethanol is normally used for chemical lysis, which predominantly eliminates the unmyelinated autonomic axons. In order to visualize the distribution of the ethanol during application, iodine-containing contrast medium is added. RESULTS: The sympathetic nervous system (SNS) controls sweat secretion via the efferent neurons; therefore, effective therapy of idiopathic palmar, axillary and plantar hyperhidrosis can be achieved when SL is performed at the corresponding level of the sympathetic trunk. Furthermore, due to the vasomotor innervation of most blood vessels, by reduction of the sympathicotonus an atony of the smooth muscles and therefore vasodilatation occurs, which is used as a palliative therapeutic option in patients with critical limb ischemia. By elimination of the afferent sensory fibers this also results in pain relief. This principle is also used in the SL therapy of the complex regional pain syndrome. CONCLUSION: After the introduction of CT guidance, major complications have become rare events. In addition to the usual risks of percutaneous interventions there are, however, a number of specific complications, such as syncope caused by irritation of cardiac sympathetic nerves in thoracic SL and ureteral injury in lumbar SL.

Prevention of type II endoleak using the AMPLATZER vascular plug before endovascular aneurysm repair.

OBJECTIVE: We evaluated the feasibility of visceral artery and lumbar artery (LA) embolization using AMPLATZER vascular plug (AVP) types 4 and 2 (AVP4, AVP2) prior to endovascular aneurysm repair (EVAR) to prevent the development of a type II endoleak. METHODS: Between January 2008 and April 2010, 45 arteries in 33 male patients were embolized with 44 AVP4 and one AVP2. Artery name and diameter; device number and size; and intervention, fluoroscopy, and deployment times for each procedure and each device were recorded. Computed tomography (CT) angiography was performed 2 days and 3, 6, 12, 18, 24, and 36 months after EVAR to confirm successful EVAR and embolotherapy, exclude endoleaks, and evaluate aneurysm shrinkage. RESULTS: AVP4 devices were implanted into the inferior mesenteric arteries in 33 cases, lumbar arteries in seven cases, and pelvic and renal arteries in two cases each. An AVP2 device was inserted into the gluteal artery in one case. The success rate was 100%, with total occlusion of all target vessels. No endoleaks were found in follow-up CT angiography. CONCLUSION: The use of AVP prior to EVAR is an efficient embolization technique that prevents the development of type II endoleaks.

[Percutaneous arteriovenous shunting in patients with severe COPD: a new interventional radiological treatment]. / Perkutane arteriovenöse Shuntanlage bei Patienten mit schwerer COPD: eine neue interventionelle radiologische Technik.

PURPOSE: The aim of this study was to evaluate the technical feasibility and safety of a new interventional radiological technique to create a shunt percutanously between the external iliac vein and artery in patients with severe COPD. MATERIALS AND METHODS: 40 patients were included in this multicenter trial. In 38 patients the artery was punctured from the vein using a novel crossing needle. A special delivery system was used to implant a novel nitinol device (ACS, ROX Medical) between the artery and the vein to maintain a 4 mm calibrated and structured fistula between the two vessels. RESULTS: Shunt implantation was successful in 38 patients. The perfused arteriovenous shunts could be well documented in DSA and the diameter was measured between 3 and 4 mm in all cases. Peri-interventional non-flow-limiting dissection of the iliac artery occurred in one patient. Post-interventional venous bleeding in two patients was treated successfully by local compression. In one patient a peripheral artery thrombembolism was successfully treated by thrombolysis. CONCLUSION: The new interventional radiological technique to create an arteriovenous shunt in the iliac vessels presented in this study has proven to be feasible and safe.

Successful selective internal radiotherapy (SIRT) in a patient with a malignant solid pseudopapillary pancreatic neoplasm (SPN).

Solid pseudopapillary neoplasms of the pancreas (SPNs, Gruber-Frantz-Tumor) are a rare entity representing 1-5% of all exocrine pancreatic tumors. The pseudocystic lesions preferentially affect young females <30 years, are mostly benign (∼90%) and normally present with unspecific symptoms. We describe the case of a 16-years-old Asian woman that was initially diagnosed with an SPN in the pancreatic head with mesenterial and hepatic metastases. After diagnosis, an extensive tumor resection was performed including pyloric-preserving pancreatic head resection followed by sequential resection of all hepatic metastases. After the patient was diagnosed with a hepatic recurrence and high intrahepatic tumor load, we chose a multimodal procedure and performed a selective internal radiotherapy (SIRT). Four years after SIRT and 10 years after initial diagnosis of metastatic SPN, the patient is in a good condition without any evidence for hepatic recurrence. This case represents a rare clinical course of a malignant and invasive SPN with an exceptionally long survival despite of high initial tumor burden. The selective internal radiotherapy is a suitable approach for inducing long-term remissions of the strongly vascularized liver metastases.

Induction of luciferase activity under the control of an hsp70 promoter using high-intensity focused ultrasound: combination of bioluminescence and MRI imaging in three different tumour models.

The in vivo temporal changes of luciferase activity were investigated under the control of an hsp70 promoter in three tumour models after the application of different intensities of high-intensity focused ultrasound (HIFU). Three cell lines, SCCVII, NIH3T3 and M21 were stably transfected with a plasmid containing the hsp70 promoter and luciferase reporter gene, and tumours were subcutaneously initiated into mice. At a size of 1300 ± 234 mm(3), the tumours were exposed to five intensities of continuous HIFU (802-1401-2157-3067-4133 W/cm(2)) for 20 sec. Bioluminescence and MR imaging were performed to assess luciferase activity and signal intensity changes in the tissue. The MRI scan protocol was pre- and post-contrast T1-wt-SE, T2-wt-FSE, DCE-MRI, diffusion-wt STEAM sequence, T2 relaxation time determination obtained on a 1.5-T GE MRI scanner. The NIH3T3 tumours showed the highest luciferase activity of 328.1 ± 7.1 fold at 24 h at a HIFU intensity of 3067 W/cm(2), the M21 tumours of 3.2 ± 0.6 fold 8 hours and the SCCVII tumours 2.9 ± 0.9 fold 4 hours post-HIFU at 2157 W/cm(2). The greatest increase in T2 signal intensity and T2 relaxation time of 20.7 ± 3.4% was seen in the SCCVII tumours. The highest contrast medium uptake of 10.1 ± 1.1% was noted in the M21 tumours, and 14.8 ± 1.9% in the SCCVII tumours. In all tumours, a significant increase in the diffusion coefficient was seen with increased HIFU intensity, the highest of which was 40.3 ± 4.1% in the SCCVII tumours. The three tumour cell lines stably transfected with the hsp70/luciferase gene showed differential luciferase activity, which peaked at different times after the application of HIFU and was dependant on tumour type and HIFU energy deposition.

[Secretin-enhanced magnetic resonance cholangiopancreaticography: value for the diagnosis of chronic pancreatitis]. / Sekretinstimulierte Magnetresonanzcholangiopankreaticografie (MRCP): Wertigkeit in der Diagnostik der chronischen Pankreatitis.

Endoscopic retrograde cholangiopancreaticography (ERCP) is the morphologic gold standard for the diagnosis of chronic pancreatitis. Magnetic Resonance Imaging (MRI) enables the visualization of not only the pancreatic duct but also the surrounding parenchyma using T2- and T1-weighted sequences before and after the application of a contrast agent. Moreover, it allows the depiction of ductal segments distal to a stenosis or occlusion. However, conventional Magnetic Resonance Cholangiopancreaticography (MRCP) was not able to achieve accuracy similar to that of ERCP. Despite many technological innovations, such as fast breath-hold acquisitions or respiratory-gated 3D sequences, this drawback could not be overcome. In recent years, secretin-enhanced MRCP has been used for the diagnosis of chronic pancreatitis. A recent study showed that secretin not only improves the visibility of the pancreatic duct and its side branches but it also enhances the diagnostic accuracy of MRCP. The sensitivity, specificity, and positive and negative predictive values were improved by the application of secretin. Moreover, the agreement between independent observers increased after the use of secretin. In addition, quantitative post-processing tools have been developed that enable the measurement of the exocrine pancreatic output non-invasively using secretin-enhanced MRCP. These tools facilitate applications, such as functional follow-up after pancreaticogastrostomy and pancreaticogastric anastomoses, evaluation of the functional status of the graft after pancreas transplantation and follow-up of pancreatic drainage procedures and duct disruption.

[Rare cause of chronic recurrent pulmonary emboli and pulmonary artery hypertension]. / Seltene Ursache chronisch rezidivierender Lungenembolien und pulmonal-arterieller Hypertonie.

HISTORY AND CLINICAL FINDINGS: A 41-year-old man with known Klippel-Trenaunay syndrome was admitted to hospital because of progressive dyspnea on exertion. Examination on admission revealed the typical signs of Klippel-Trenaunay syndrome, predominantly of the left leg. INVESTIGATIONS: D-dimers were significantly increased. Contrast-enhanced computed tomography of the chest revealed multiple small pulmonary arterial emboli in subsegmental arteries on both lungs. Pulmonary arterial digital subtraction angiography revealed extensive peripherally localized perfusion defects. Pulmonary artery pressure measurement demonstrated bilateral pulmonary artery hypertension. Phlebography of the left lower leg showed marked varices in the calf. There was also a persisting sciatic vein. DIAGNOSIS, TREATMENT AND COURSE: The recurrent peripheral pulmonary emboli with pulmonary arterial hypertension was a complication of a Klippel-Trenaunay syndrome. Another rare entity of this syndrome was a persisting sciatic vein. Heparinization was initiated, followed by oral anticoagulation. As the patient had not been anticoagulated before, implantation of an inferior vena cava filter was not deemed appropriate. CONCLUSIONS: Recurrent peripheral pulmonary emboli leading to chronic pulmonary artery hypertension is a rare but typical complication of Klippel-Trenaunay syndrome. Early recognition of this syndrome and any complications as a separate entity, as well as initiation of therapeutic measures, like anticoagulation or early pulmonary thrombendarterectomy for chronic pulmonary artery emboli, are of prognostic importance.