[Image-guided pain therapy. Sympathicolysis]

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.

Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis)

We describe the bi-directed eyes of a mesopelagic teleost fish, Rhynchohyalus natalensis, that possesses an extensive lateral diverticulum to each tubular eye. Each diverticulum contains a mirror that focuses light from the ventro-lateral visual field. This species can thereby visualize both downwelling sunlight and bioluminescence over a wide field of view. Modelling shows that the mirror is very likely to be capable of producing a bright, well focused image. After Dolichopteryx longipes, this is only the second description of an eye in a vertebrate having both reflective and refractive optics. Although superficially similar, the optics of the diverticular eyes of these two species of fish differ in some important respects. Firstly, the reflective crystals in the D. longipes mirror are derived from a tapetum within the retinal pigment epithelium, whereas in R. natalensis they develop from the choroidal argentea. Secondly, in D. longipes the angle of the reflective crystals varies depending on their position within the mirror, forming a Fresnel-type reflector, but in R. natalensis the crystals are orientated almost parallel to the mirror's surface and image formation is dependent on the gross morphology of the diverticular mirror. Two remarkably different developmental solutions have thus evolved in these two closely related species of opisthoproctid teleosts to extend the restricted visual field of a tubular eye and provide a well-focused image with reflective optics.

Comparison of six different specimen types for Epstein-Barr viral load quantification in peripheral blood of pediatric patients after heart transplantation or after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Epstein-Barr Virus (EBV) a gamma-herpes virus is associated with a spectrum of lymphoid and epithelial malignancies including posttransplant lymphoproliferative disorders (PTLD). EBV-load measurement has been shown to be important for the monitoring of these patients. However, in contrast to the viral quantification of human immunodeficiency virus or human hepatitis C virus, the EBV-load measurement has not been completely standardized as yet.

OBJECTIVES

In this study, we compared the EBV DNA levels in whole blood (WB), plasma, peripheral mononuclear cells (PBMC) and B-cells (BC) in children and adolescents after heart transplantations (HTx) and allogeneic hematopoietic stem cell transplantations (HSCT).

STUDY DESIGN

In a period of 2 years (from May 2007 to May 2009) we collected 547 samples of 96 cardiac transplant recipients and 248 samples of 37 patients who underwent HSCT. For EBV DNA quantification we used a duplex real-time PCR (ABI Prism 7500, Applied Biosystems). Additionally, EBV-load of PBMC and BC were normalized with respect to endogenous cell DNA.

RESULTS

In both patient populations we found no significant difference of test sensitivity for the EBV detection. In PBMC as well as BC, there was a high correlation between the analysis of cells with and without normalization in both populations. Spearman's correlation coefficient ρ between PBMC without and PBMC with normalization was ρ=0.98 (P<0.0001) in patients after HTx and ρ=0.99 (P<0.0001) in patients after HSCT. Correlation between BC with and without normalization was ρ=0.98 (P<0.0001) in patients after HTx and ρ=0.995 (P<0.0001) in patients after HSCT. When comparing the different blood compartments for EBV quantification in both populations, the strongest correlations were found between the EBV DNA levels in WB and PBMC (HTx: ρ=0.93, P<0.0001; HSCT: ρ=0.81, P<0.0001) followed by PBMC and BC (HTx: ρ=0.87, P<0.0001; HSCT: ρ=0.81, P<0.0001) as well as WB and BC (HTx: ρ=0.86, P<0.0001; HSCT: ρ=0.75, P<0.0001). In contrast, the correlation coefficients between plasma and the other blood compartments (WB as well as PBMC or BC) were lower. Six patients developed seven episodes of PTLD (five patients after HTx and one after renal transplantation). Analyzing the different blood compartments, we found that a threshold of WB ≥20,000EBV-copies/ml and plasma ≥1000EBV-copies/ml had the highest sensitivities and specificities (WB: sensitivity 100%, specificity 87% and plasma: sensitivity 88%, specificity 98%).

CONCLUSION

Normalization towards an endogenous control does not seem to be necessary for EBV quantification in peripheral blood. The analysis of whole blood correlates well with B-cells and PBMC. Routine screening of EBV DNA in whole blood appeared to be a useful tool supplemented by EBV-load measurement in plasma to discriminate chronic high EBV-load carrier without risk for PTLD from those who are at risk for PTLD. Values in whole blood higher than 20,000EBV-copies/ml WB and plasma values higher than 1000EBV-copies/ml plasma indicated PTLD in our series.

An inflammatory myofibroblastic tumor of the stomach as a rare cause of gastric outlet obstruction in an 8-month-old infant

Inflammatory myofibroblastic tumors (IMT) are a rare entity. Localization in the stomach is extremely seldom and almost exclusively seen in children. Invasive growth of IMT may lead to irresectability or recurrence. In an 8-month-old girl presented with repetitive vomiting for several days. Complete surgical resection of a gastric IMT was possible.

Sarcoidosis following Cushing's syndrome: A report of two cases and review of the literature

Cushing's syndrome is characterized by excessive elevation of glucocorticoid concentrations. In rare cases, the treatment of Cushing's syndrome may result in unmasking or aggravation of diseases responsive to glucocorticoid medication. We report two cases of sarcoidosis following Cushing's syndrome. A 43 year-old male developed cutaneous sarcoidosis and mediastinal lymphadenopathy after resection of an ACTH-secreting pituitary microadenoma. A 32 year-old female showed cutaneous sarcoidosis, arthralgia, mediastinal lymphadenopathy and elevation of angiotensin-converting enzyme and interleukin 2-receptor concentrations after traumatic adrenal bleeding, which ceased formerly undiagnosed hypercortisolism caused by an adrenal adenoma. Sarcoidosis seems to be a rare sequel following the treatment of hypercortisolism. Skin affections were present and suggestive for the diagnosis in all reported cases. As some cases are probably missed when skin affections are lacking, a more frequent evaluation of patients after Cushing's syndrome for the possible diagnosis of sarcoidosis might be necessary.

Palliativtherapie der malignen Ösophagusobstruktion mit selbstexpandierenden Metallendoprothesen

A total of 23 self-expanding metal stents were implanted in 17 patients (12 men, 5 women; mean age 66 [44-83] years) with inoperable malignant obstruction of the oesophagus or the oesophago-gastric junction. A primary success was achieved in all, a good functional result in 16 (94%). There were no complications. In the follow-up period (mean of 15.2 +/- 13 weeks) re-obstruction by the tumour process occurred in three patients. Twelve patients died after a mean survival time of 15.8 +/- 14 weeks. In ten of these the stent was still patent at death, while two had again developed dysphagia. The cumulative patency rate of the stents was 79%. These observations indicate that self-expanding metal stents can achieve satisfactory palliation in dysphagia due to a malignancy. The mortality and morbidity rates of the method seem to be less than those of other palliative measures.

[Peripheral arterial obstruction and acute lower limb ischemia]

In this article, current evidence-based treatment recommendations for acute and chronic lower limb ischemia will be presented considering the varied possibilities of endovascular techniques and open surgical vascular strategies. Beside presentation of the different therapeutic possibilities, advantages of the combination of both techniques will be described. Despite the BASIL trial, there are no prospective randomised controlled trials comparing endovascular and open surgical interventions. Different therapeutic rules along the different vascular segments will be discussed for both acute and chronic peripheral arterial disease. Generally it can be stated that aortoiliac revascularization for chronic obstructions is increasingly being carried out by endovascular means or hybrid procedures using a minimally invasive femoral approach, whereas acute occlusions in this vascular segment are still treated with open surgical techniques (Fogarty balloon thrombectomy). In the infrainguinal region, endovascular therapeutic strategies are gaining favor. However, multilevel occlusions and long-segment obstructions in the femoral and popliteal segment are still treated by bypass procedures. Acute ischemia in the infrainguinal segment is increasingly treated with endovascular methods (local thrombolysis and percutaneous thrombectomy).

[Periinterventional prophylactic antibiotics in radiological port catheter implantation]

PURPOSE

To evaluate whether catheter-related infections after radiologically placed port catheters can be reduced by single-shot periinterventional antibiosis.

MATERIALS AND METHOD

Between January and September 2002, 164 consecutive patients with indication for central venous port catheter implantation were included in the present study. During implantation the interventional radiologist was responsible for deciding whether to administer a prophylactic single-shot antibiosis. The prophylactic antibiosis entailed intravenous administration of ampicillin and sulbactam (3 g Unacid, Pfizer) or 100 mg ciprofloxacine (Ciprobay, Bayer) in the case of an allergy history to penicillins. Catheter-related infection was defined as a local or systemic infection necessitating port catheter extraction.

RESULTS

Indication for port catheter implantation was a malignant disease requiring chemotherapy in 158 cases. The port catheter (Chemosite [Tyco Healthcare] [n = 123], low-profile [Arrow International] [n = 35], other port system [n = 6]) was implanted via sonographically guided puncture of the right jugular vein in 139 patients, via the left jugular vein in 24 cases and via the right subclavian vein in one patient. 75 patients received periinterventional prophylactic antibiosis (Unacid [n = 63] Ciprobay [n = 12]) and 89 patients did not receive antibiosis. The prophylactic antibiosis caused a minor allergic reaction in one patient that improved with antihistamic and corticoid medication. A total of 7 ports, 6 without prophylactic antibiosis versus one with periinterventional prophylaxis, were extracted due to infectious complications.

CONCLUSION

Single-shot periinterventional prophylactic antibiosis can reduce early and late infectious complications after radiological-interventional placement of central venous port catheters.

Langzeitergebnisse nach Ballonangioplastie kruraler Arterien

PURPOSE

To evaluate the technical success rate, procedure-related complications, and clinical long-term results for patients who underwent infrapopliteal angioplasty.

MATERIALS AND METHODS

We retrospectively evaluated all patients who underwent infrapopliteal angioplasty to treat critical chronic limb ischemia or severe claudication from 1/1997 to 12/1999. We excluded patients with acute (< 2 weeks) limb ischemia. Procedure-related data were prospectively documented in a database and analyzed with a focus on the technical success rate and procedure-related complications. In addition all clinical documents were analyzed, and a follow-up examination was performed or telephone interviews were conducted with patients, relatives and referring doctors for follow-up. The primary end points were the limb salvage rate and patient survival rate. The secondary end points included the complication rate, technical success rate, and walking distance.

RESULTS

112 patients with a mean age of 72 years (41 women, 71 men) underwent crural angioplasty on 121 limbs. Four patients suffered from severe claudication (Rutherford category 3) and all others had critical chronic limb ischemia (category 4 to 6). The complication rate was 2.7 %. The technical success rate was 92 %. The ankle brachial index increased from 0.59 to 0.88. The mean walking distance increased significantly from 52 +/- 66 to 284 +/- 346 meters at the time of follow-up. The limb salvage rate was 83.6 % after one year and 81.1 % after three years. The mean survival rate according to Kaplan-Meier was 79.4 %, 69.2 %, and 54.2 % at 1, 2, and 3 years, respectively. Patients with at least one patent run-off vessel after angioplasty had a significantly better limb salvage rate. Diabetes was not a risk factor for limb salvage.

CONCLUSION

Infrapopliteal angioplasty shows a high technical success rate with an acceptable complication rate. The clinical long-term success seems favorable if a least one open run-off vessel was able to be achieved. However, the survival rate was limited by the co-morbidity in this patient group.

High seroprevalence of Epstein-Barr virus in children with multiple sclerosis

We studied seroprevalence and concentrations of Epstein-Barr virus (EBV) antibodies in 147 pediatric patients with multiple sclerosis (MS) and paired controls. The children with MS showed a near-complete seropositivity for EBV antibody against virus capsid antigen (98.6% vs 72.1% in controls, p = 0.001) but did not display serologic evidence for a recent EBV infection. EBV antibody concentrations of pediatric patients with MS were significantly higher vs controls.

[Dysphagia caused by neurogenic deglutition disorders and diffuse idiopathic skeletal hyperostosis (DISH)]

BACKGROUND

Diffuse idiopathic skeletal hyperostosis (DISH) may lead to dysphagia caused by osteophytes of the cervical spine. Osteophytes can be resected transorally or transcervically, but operative ablation should not be indicated generously because of the threat of severe complications.

PATIENT

A fifty-year-old man with dysphagia and loss of weight of 15 kg in the last three months is presented. He also suffered from a brain damage during infancy which caused grand-mal-seizures. One seizure lead to cardiac arrest which required cardio-pulmonary resuscitation and subsequent tracheostomy. A spheric tumor of the posterior pharyngeal wall could be seen endoscopically, it appeared radiologically as an osteophytic formation of the segments C (3) - C (5). Ossification of the anterior longitudinal ligament was also seen. Diagnosis of DISH was made on the basis of these results. Contrast imaging of the esophagus and videofluoroscopy showed aspiration in terms of neurogenic disorders. The patient received a percutaneous gastrostomy after his case was discussed with neurologic and orthopaedic colleagues, because a causal therapy of the combined disease seemed to be impossible.

CONCLUSION

Dysphagia in the presented case was caused by a combination of neurogenic deglutition disorders and oropharyngeal obstruction through osteophytes. Surgical removal of the osteophytes was not indicated because it would have put the patient at a certain risk, but only a part of the underlying problem would have been removed. Symptomatic therapy with a gastrostomy secures normocaloric diet. The patient's weight remained stable and he can follow his habitual daily routine.

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.

An authentic malignant epithelioid hemangioendothelioma of the thyroid: a case report and review of the literature

Hemangioendotheliomas of the thyroid are neoplasms that are rarely encountered in the Alpine region in Europe. The endemic goiter in this iodine-deficient region can be considered as a predisposing factor. We report the second case of an epithelioid hemangioendothelioma (EHE) of the thyroid gland and the first clinical case with malignant behavior. A 73-year-old woman with a long history of multinodular goiter presented with a rapidly growing thyroid mass, free of distant metastases. A total thyroidectomy was performed. Histologically the lesion had characteristic epithelioid and spindle cell proliferation in a background of chondromyxoid stroma. Cytoplasmic vacuolization in the epithelioid and spindle cells were present. Tumor cells were positive for factor VIII-related antigen, MNF116, PAN-ceratin, CD 34, and CD 31 and negative for cytokeratin allowing the diagnosis of EHE. Nine months after the primary resection the tumor locally recurred. A palliative resection was performed in a second operation followed by interferon-alpha therapy. The patient rapidly developed a second local relapse and died 13 months after the diagnosis of an EHE had been made. An improvement of the very poor prognosis of this rare tumor may depend on early tumor diagnosis and surgery combined with a multimodal treatment.

[Contrast media pressure injection using a portal catheter system--results of an in vitro study]

PURPOSE

Are implanted central venous port catheters suitable for contrast media pressure (power) injection in computed tomography?

MATERIAL AND METHODS

In an in vitro study 100 ml of contrast medium (Ultravist 370, Schering, Berlin, Deutschland) was injected through 20 different port catheter systems using a power injector (Stellant, Medrad, Inianola, USA) with a pressure limit of 325 PSI. The injection rate was increased from 2 ml/s to 10 ml/s in increments of 2 ml/s. The maximum injection pressure and maximum injection rate were assessed.

RESULTS

An injection rate of 2 ml/s was possible in all catheter systems. Injection rates of 4 ml/s in 18 systems, 6 ml/s in 13 systems and 8 ml/s in 6 systems were achieved. With a given pressure limit of 325 PSI an injection rate of 10 ml/s was not possible in any of the port catheter systems. There were no catheter ruptures, catheter disconnections or contrast extravasations noted.

CONCLUSION

Power injection of contrast media with a pressure limit of 325 PSI seems to be tolerated by port catheter systems. Most of the evaluated port systems allow flow rates suitable for multislice computed tomography requiring rapid contrast injection.

Successful treatment of solid-pseudopapillary tumor of the pancreas with multiple liver metastases

The solid-pseudopapillary tumor (SPT) is a very rare pancreatic neoplasm that predominantly affects young females. About 450 cases have been described in the world literature and approximately 20% of the reported patients were children. The occurrence of SPT with distant metastases in children is extremely rare with only two previously reported cases. We now report a 16-year-old Asian girl with a large SPT and synchronous multiple liver metastases who was successfully treated in a 2-step strategy, including initial pylorus-preserving partial duodenopancreatectomy, right hemicolectomy, resection and allografting of the portal vein and secondary resection of 12 liver metastases. The patient is disease free after a follow-up of 18 months after resection of the primary tumor, suggesting that an aggressive surgical treatment might also be justified for metastasized SPT.

The pupillary response of cephalopods

This paper provides the first detailed description of the time courses of light-evoked pupillary constriction for two species of cephalopods, Sepia officinalis (a cuttlefish) and Eledone cirrhosa (an octopus). The responses are much faster than hitherto reported, full contraction in Sepia taking less than 1 s, indicating it is among the most rapid pupillary responses in the animal kingdom. We also describe the dependence of the degree of pupil constriction on the level of ambient illumination and show considerable variability between animals. Furthermore, both Sepia and Eledone lack a consensual light-evoked pupil response. Pupil dilation following darkness in Sepia is shown to be very variable, often occurring within a second but at other times taking considerably longer. This may be the result of extensive light-independent variations in pupil diameter in low levels of illumination.

Plasma viral load of Epstein-Barr virus and risk of multiple sclerosis

Elevated antibody titers to Epstein-Barr virus (EBV) have been found prior to the onset of multiple sclerosis (MS) and EBV has been found in serum of patients with MS exacerbations. We conducted a prospective, nested case-control study in the Nurses' Health Study and Nurses' Health Study II cohorts to determine whether plasma EBV viral load in healthy adults predicts the risk of MS. MS cases with blood collected before onset (n = 18) or diagnosis (n = 13) and 62 healthy controls were matched by age and time of blood collection. EBV viral load in plasma was measured by real time polymerase chain reaction. Presence of EBV in plasma was associated with an increased risk of MS (relative risk = 2.5, 95% CI 0.78-7.8, P = 0.12). Adjusting for smoking, ancestry, and latitude of residence at birth did not materially change this result. However, no association was found between the EBV viral load and risk of MS. These results support a role for EBV in the etiology of MS, but need to be confirmed in a larger study.

[Embolization of pulmonary arteriovenous malformations with electrolytically detachable coils in patients with hereditary hemorrhagic telangiectasia]

BACKGROUND

Pulmonary arteriovenous malformations (PAVM) can be found in approximately 20 % to 35 % of patients with hereditary hemorrhagic telangiectasia (HHT). PAVM should be treated since they are a source of paradoxical embolization, potentially resulting in severe neurologic complications. The treatment of choice is the endovascular embolization with coils.

PATIENTS AND METHODS

Seven patients with HHT underwent superselective embolization of PAVM detected during screening for PAVM. Four patients had a single PAVM and one patient 3, 4 and 5 PAVMs, respectively. Electrolytically detachable coils were used for embolization. In addition, coils with synthetic fibers were used during 6 embolizations for completion of embolization.

RESULTS

Embolization was technically successful in all patients. Complete primary occlusion was achieved in all PAVM. No coil migration or occlusion of unaffected pulmonary arteries was observed. After embolization, one patient developed a small pleural effusion, which was treated symptomatically.

CONCLUSION

As a minimally invasive procedure, superselective embolization is the treatment of choice in treating PAVM in patients with HHT. With the use of electrolytically detachable coils, the ideal coil size can be chosen and exact placement achieved without the risk of coil migration or occlusion of unaffected pulmonary arteries.

Hochmalignes Intimasarkom in einem Aneurysma der infrarenalen Bauchaorta

Primary intimal sarcomas of the aorta are extremely rare and aggressive tumors metastasizing into bones and visceral organs including liver, kidneys, adrenal glands, and lung. The first symptoms are often nonspecific and often caused by arterial embolism. We report a case with an incidental finding of primary intimal sarcoma in an aneurysm of a patient with claudication due to tumor embolization.

Regulation of intestinal phosphate cotransporter NaPi IIb by ubiquitin ligase Nedd4-2 and by serum- and glucocorticoid-dependent kinase 1

Serum and glucocorticoid-inducible kinase 1 (SGK1) is highly expressed in enterocytes. The significance of the kinase in regulation of intestinal function has, however, remained elusive. In Xenopus laevis oocytes, SGK1 stimulates the epithelial Na(+) channel by phosphorylating the ubiquitin ligase Nedd4-2, which regulates channels by ubiquitination leading to subsequent degradation of the channel protein. Thus the present study has been performed to explore whether SGK1 regulates transport systems expressed in intestinal epithelial cells, specifically type IIb sodium-phosphate (Na(+)-P(i)) cotransporter (NaPi IIb). Immunohistochemistry in human small intestine revealed SGK1 colocalization with Nedd4-2 in villus enterocytes. For functional analysis cRNA encoding NaPi IIb, the SGK isoforms and/or the Nedd4-2 were injected into X. laevis oocytes, and transport activity was quantified as the substrate-induced current (I(P)). Exposure to 3 mM phosphate induces an I(P) in NaPi IIb-expressing oocytes. Coinjection of Nedd4-2, but not the catalytically inactive mutant (C938S)Nedd4-2, significantly downregulates I(P), whereas the coinjection of (S422D)SGK1 markedly stimulates I(P) and even fully reverses the effect of Nedd4-2 on I(P). The effect of (S422D)SGK1 on NaPi IIb is mimicked by wild-type SGK3 but not by wild-type SGK2, constitutively active (T308D,S473D)PKB, or inactive (K127N)SGK1. Moreover, (S422D)SGK1 and SGK3 phosphorylate Nedd4-2. In conclusion, SGK1 stimulates the NaPi IIb, at least in part, by phosphorylating and thereby inhibiting Nedd4-2 binding to its target. Thus the present study reveals a novel signaling pathway in the regulation of intestinal phosphate transport, which may be important for regulation of phosphate balance.

Transarterial chemoembolization of advanced liver metastases of neuroendocrine tumors--a retrospective single-center analysis

BACKGROUND

In neuroendocrine tumors, metastases are a negative prognostic factor for survival and quality of life. Transcatheter arterial chemoembolization (TACE) is thought to be an effective symptomatic and antiproliferative treatment in patients with otherwise progressive disease.

METHODS

62 chemoembolization procedures in 26 patients with progressive neuroendocrine tumors were reviewed. The underlying disease was carcinoid syndrome in 10, non-functional midgut tumor in 2, non-functional pancreatic tumor in 7, malignant insulinoma in 2 patients, non-functional tumor of the stomach in 1 and of unknown origin in 4 patients. Tumor burden of the liver was <25% in 3, 25-50% in 11, 50-75% in 6 and >75% in 6 patients.

RESULTS

TACE was technically successful in 57 cases. Four patients developed minor and 5 major complications. The 30-day mortality rate was 7.7%. According to WHO criteria, 14 patients had no change in tumor burden, 2 had regression and 5 progress after chemoembolization. Patients with a tumor burden >75% of the liver did not benefit from TACE due to the development of major complications, whereas patients with low (<50%) tumor burden and high (>50%) lipiodol uptake showed a trend towards longer survival. Five-year survival time after diagnosis was 48%. Patients treated with octreotide and/or alpha-interferon had no benefit from chemoembolization with regard to their carcinoid syndrome.

CONCLUSIONS

In this retrospective study, patients with low (<50%) tumor burden and high (>50%) lipiodol uptake responded better to TACE than end-stage patients.

Ultraschall- und durchleuchtungsgesteuerte Implantation peripher inserierter zentral-venöser Katheter (PICC)

PURPOSE

Evaluation of ultrasound- and fluoroscopy-guided implantation of peripherally inserted central venous catheters (PICCs).

MATERIALS AND METHODS

In 32 patients (12 males, 20 females; mean age 64.1 +/- 11.9 years) with clinical indication for long term central venous catheter (chemotherapy: N = 5; parenteral nutrition and fluid substitution: N = 26; parenteral pain therapy: N = 1) a PICC was placed by an interventional radiologist using ultrasound guidance.

RESULTS

The placement of the PICC was technically successful in 31 (96.9%) patients, with placement of 20 single-lumen 5F PICCs, 4 double-lumen 6F PICCs and 7 double-lumen 7F PICCs. The mean duration of catheter usage was 28.4 (2 - 161) days with a total of 910 catheter days. No catheter occlusions were recorded. Two patients developed a superficial venous thrombosis of the upper extremity. The resulting thrombotic rate was 2.2 per 1000 catheter days. No catheter associated infection was recorded.

CONCLUSION

The ultrasound guided placement of peripherally inserted central venous catheters (PICCs) via a superficial vein of the upper extremity is a practical alternative to central catheters via central veins.

Expansion of EBV latent membrane protein 2a specific cytotoxic T cells for the adoptive immunotherapy of EBV latency type 2 malignancies: influence of recombinant IL12 and IL15

BACKGROUND

EBV-associated malignancies with a Type II latency gene expression pattern, such as EBV-positive HD, or nasopharyngeal carcinoma, frequently express the EBV latency Ag LMP2a. Hence, they provide a potential target for adoptive immunotherapy using in vitro-generated LMP2a-specific cytotoxic T lymphocytes (CTL). In this study, LMP2a-specific CTL were specifically amplified and the influence of rIL12 and rIL15 on the culture outcome was tested.

METHODS

PBMC from donors were stimulated twice with autologous DC transduced with an adenovirus vector expressing LMP2a. This led to a significant expansion of LMP2a-tetramer-specific CTL, which were subsequently further expanded with autologous EBV-transformed B-lymphoblastoid cells (LCL). The addition of rIL12 and rIL15 to the standard IL2-containing culture medium enhanced the proliferation of LMP2a-specific CTL.

RESULTS

While rIL15 did not change the pattern of cytokines secreted by LMP2a-CTL, rIL12 enhanced the production of Th1/Tc1 cytokines, such as IFN-n, while suppressing the production of the Th2/Tc2 cytokine IL5.

DISCUSSION

Stimulation of CTL cultures with rIL12 or rIL15 will generate CTL more rapidly, facilitating the application of this approach for patients with these EBV-associated disorders.

Accommodation behaviour during prey capture in the vietnamese leaf turtle ( Geoemyda spengleri )

Vietnamese leaf turtles ( Geoemyda spengleri) were tested for their ability to focus on prey objects at various distances. Accommodation was continuously measured by infrared photoretinoscopy. All animals investigated during this study showed a surprisingly high precision of accommodation over a range of over 30 D. Measured accommodation matched the target distance accurately for distances between 3 and 17 cm. The turtles switched between independent and coupled accommodation in the two eyes. Independent accommodation was observed when the turtles inspected their environment visually without a defined object of interest. Coupled accommodation was only observed during binocular prey fixation. When a turtle aimed at a target, the symmetrical focus of both eyes persisted even if vision was totally blocked in one eye or altered by ophthalmic lenses. This suggests that the eyes were linked by internal neuronal mechanisms. The pupil of the eye responded clearly to changes in ambient light intensity. A strong decrease in pupil size was also observed when the eye was focused on a close target. In this case, the constriction of the pupil probably aids in the deformation of the eye lens during near-accommodation.

Central venous access catheters: radiological management of complications

A great variety of central venous access devices such as tunneled and non-tunneled central venous catheters (CVC) as well as port systems are implanted by interventional radiologists at an increasing rate. There are some possible immediate, early, and late complications related to the implantation technique, care, and maintenance of CVCs. This review will illustrate possible complications of CVCs and will discuss risk factors. Different strategies will be shown regarding the prevention and treatment of complications.

[1-molar Gadobutrol as a contrast agent for digital subtraction angiography]

PURPOSE

To evaluate one-molar Gadobutrol solution as contrast media for intra-arterial digital subtraction angiography (DSA).

MATERIALS AND METHODS

In 10 patients (7 males, 3 females; mean age 68 years) with contraindications for the use of iodinated contrast media (n = 8 renal insufficiency, n = 2 previous allergic reaction), Gadobutrol solution (1 mol/l) was used as contrast media for DSA. Six diagnostic angiograms and four DSAs for percutaneous transluminal angioplasty (PTA) were performed.

RESULTS

In all cases, Gadobutrol yielded sufficient contrast for diagnostic DSA. Because of dose limitations (maximum 0.3 ml/kg body weight), small amounts of iodinated contrast media were administered to complete the angiographic procedure (mean 15 ml) in two patients. Allergic reactions were not recorded in any patient. In patients with pre-existing renal insufficiency, mean serum creatinine level was not statistically significant different from the initial level (mean 2.88 mg/dl before and 2.83 mg/dl after DSA). Selective injection of Gadobutrol resulted in temporary discomfort.

CONCLUSION

One molar Gadobutrol is an alternate contrast media for DSA in patients with contraindications for iodinated contrast media. Current dose limitations require selective injections.

Terminal nerve and vision

The vertebrate retina receives efferent input from different parts of the central nervous system. Efferent fibers are thought to influence retinal information processing but their functional role is not well understood. One of the best-described retinopetal fiber systems in teleost retinae belongs to the terminal nerve complex. Gonadotropin-releasing hormone (GnRH) and molluscan cardioexcitatory tetrapeptide (FMRFamide)-containing fibers from the ganglion of the terminal nerve form a dense fiber plexus in the retina at the border of the inner nuclear and inner plexiform layer. Peptide-containing fibers surround and contact perikarya of dopaminergic interplexiform cells in teleost retina. In vitro experiments demonstrated that exogenously supplied GnRH mediates dopaminergic effects on the membrane potential and on the morphology of dendritic tips (spinules) of cone horizontal cells. These effects can be specifically blocked by GnRH-antagonists, indicating that the release of dopamine and dopamine-dependent effects on light adaptation of retinal neurons are affected by the terminal nerve complex. Recent data have shown that olfactory information has an impact on retinal physiology, but its precise role is not clear. The efferent fiber of the terminal nerve complex is one of the first retinopetal fiber systems for which the sources of the fibers, their cellular targets, and several physiological, morphological, and behavioral effects are known. The terminal nerve complex is therefore a model system for the analysis of local information processing which is influenced by a distinct fiber projection.

[Radiological diagnosis and treatment of acute limb ischemia]

Acute limb ischemia is associated with significant morbidity and mortality, despite diagnostic and therapeutic advances. Threatened limbs require immediate imaging in order to determine the subsequent therapeutic procedures. Conventional angiography in the DSA technique still has advantages over CT and MR angiography. In acute arterial occlusions below the femoral bifurcation, endovascular treatment with intra-arterial local thrombolysis or percutaneous thrombectomy is an alternative to open vascular surgical procedures. The following article describes diagnostic and therapeutic strategies for acute limb threat induced by arterial occlusion.

Die transjuguläre Implantation venöser Portkathetersysteme

PURPOSE

Prospective analysis of success and complication rates of chest port implantation via the internal jugular vein.

MATERIALS AND METHODS

In 50 consecutive patients (25 men, 25 women; mean age 61 +/- 14 years) the internal jugular vein was punctured under ultrasound guidance. Through this access, a port system was inserted and the catheter tip was placed at the cavoatrial junction. The port reservoir was implanted into a subcutaneous infraclavicular pocket and fixed to the fascia of the pectoralis muscle. Indications for port implantation were chemotherapy (n = 46), total parenteral nutrition (n = 2) or intravenous medication (n = 2).

RESULTS

A chest port catheter system was successfully implanted in all 50 patients. The mean duration of placement was 90 +/- 65 catheter days. No complications occurred during implantation. In the post-interventional period a single catheter dysfunction occurred (0.22 per 1,000 catheter days). Two local infections occurred in the early post-interventional period (0.43 per 1,000 catheter days). One port system had to be explanted prematurely due to pain.

CONCLUSION

The ultrasound guided puncture of the internal jugular vein enables a safe access for insertion of a central venous port catheter system and is associated with a very low complication rate. Port placement via this access vein should therefore be the primary treatment.

[Treatment of malignant biliary occlusion by means of transhepatic percutaneous biliary drainage with insertion of metal stents--results of an 8-year follow-up and analysis of the prognostic parameters]

PURPOSE

To analyze outcome and predictive factors for patient survival and patency rates of unresectable malignant biliary obstruction treated with percutaneous transhepatic insertion of metal stents.

MATERIALS AND METHODS

This is a retroslective analysis of 130 patients treated in one interventional radiological center with data collected from patient records and by telephone interviews. The procedure-related data had been prospectively documented in a computer data base. The Kaplan-Meier analysis was performed for univariate and multivariate comparison of survival and patency rates with the log-rank test used for different tumor types. Predictive factors for survival and 30-day mortality were analyzed by a stepwise logistic regression.

RESULTS

Underlying causes of malignant biliary obstructions were cholangiocarcinoma in 50, pancreatic carcinoma in 29, liver metastases in 27, gallbladder carcinoma in 20, and other tumors in 4 patients. The technical success rate was 99 %, the complication rate 27 % and the 30-day mortality 11 %. Primary patency rates (406 days with a median of 207 days) did not differ significantly for different tumor types. The survival rates were significantly (p = 0.03 by log-rank test) better for patients with cholangiocarcinoma than for patients with pancreatic carcinoma and liver metastases. Multiple regression analysis revealed no predictive factor for patient survival and 30-day mortality.

CONCLUSION

Percutaneous transhepatic insertion of metal biliary endoprostheses offers a good initial and long-term relief of jaundice caused by malignant biliary obstruction. Although survival rates for patients with cholangiocarcinoma are better than for other causes of malignant biliary obstruction, a clear predictive factor is lacking for patients undergoing palliative biliary stent insertion.

Immunotherapy for Hodgkin's disease

EBV proteins present in the malignant Hodgkin Reed-Sternberg (HR-S) cells of about 40% of patients with Hodgkin's Disease (HD) provide targets for immunotherapy with virus-specific cytotoxic T lymphocytes (CTL). However, Hodgkin tumors use multiple strategies to avoid CTL, including down-regulation of immunodominant EBV antigens, and secretion of cytokines and chemokines such as TGF-beta, that inhibit the activation of CTL and professional antigen-presenting cells (APC). To be effective against this tumor, CTL must resist some or all of these strategies. Thirteen patients with multiply-relapsed HD received EBV-specific CTL, generated ex vivo using the autologous EBV-transformed B cells (LCL) as stimulator cells. After CTL infusion, EBV-specific immunity increased, virus load decreased, CTL homed to sites of malignancy and persisted for up to ten months. Clinically, CTL produced resolution of B symptoms and mixed tumor responses including one complete remission of residual disease remaining after autologous bone marrow transplant. However, no complete remission of bulky disease was achieved. Although LMP2-specific CTL activity could be detected in some of the infused CTL lines, they were present in low frequency. In pre-clinical studies, LMP1 and LMP2-specific CTL could be produced by stimulating PBMC from patients and normal donors with autologous dendritic cells expressing LMP1 or LMP2 from adenoviral vectors. Further, CTL could be rendered resistant to the devastating effects of TGF-beta by transduction with a retrovirus vector expressing a dominant-negative TGF-beta receptor, while transgenic IL-12 could increase the expression of Th1 and decrease that of Th2 cytokines. Future clinical studies will test the efficacy of CTL with improved antigen-specificity and resistance to Hodgkin immune evasion strategies.

Rotational digital cholangiography (RDC) and 3D-cholangiography (3DC) for guidance of percutaneous biliary drainage procedures

PURPOSE

To evaluate whether RDC and 3DC help clarifying anatomic details in biliary duct disease and is useful for guidance of drainage procedures.

MATERIALS AND METHODS

RDC was conducted in 11 consecutive patients (8 male, 3 female, mean age 63 years). Nine patients underwent PTBD for malignant biliary duct stenosis, one patient because of ischemic stenosis after hepaticojejunostomy and one patient presented with an infected biloma. Images were obtained after initial bile duct puncture during single breath hold from 120 projection angles using a rotating C-arm. These images were immediately available and evaluated in order to facilitate the definitive drainage procedure. For additional 3D reconstruction, data were sent to a dedicated workstation and judged by a blinded observer.

RESULTS

The availability of a rotating data set of images was judged to be helpful in three patients with complex anatomical situations. Additionally, RDC holds the potential to reduce fluoroscopy time. 3DC allowed analysis of the hepatic bifurcation from different viewing angles in 10 cases with high spatial resolution (mean voxel size 480 micro micro m 3). This may allow a better classification of hilar obstructions according to our preliminary observations.

CONCLUSION

Images from RDC and 3DC are helpful in guiding PTBD procedures and for better diagnosis in selected patients with hilar biliary duct stenoses.

Magnetic resonance phase contrast velocity measurement for non-invasive follow up after percutaneous transluminal angioplasty

BACKGROUND

The aim of this study was to evaluate magnetic resonance phase contrast velocimetry (MRVL) as a non-invasive follow up tool to assess restenosis after percutaneous transluminal angioplasty (PTA).

PATIENTS AND METHODS

We prospectively investigated 51 consecutive patients who underwent PTA of the femoropopliteal region. MRVL was conducted prior, one day, six weeks, twelve weeks and 24 weeks after PTA using a circular polarized extremity coil and a gradient echo sequence (TR/TE 600/6 ms, flip angel 30 degrees, slice thickness 10 mm). Hemodynamic data, derived from the MR phase contrast sequence, allowed to calculate the degree of area stenosis of the lesion treated with PTA. These data were correlated with clinical hemodynamic parameters (ankle-brachial index and walking distance).

RESULTS

The mean grade of area stenosis was 69% +/- 27% before PTA, 30% +/- 20% one day, 29% +/- 23% six weeks, 39% +/- 17% twelve weeks and 42% +/- 18% 24 weeks after PTA and correlated well with clinical data and the post angioplasty clinical course of the patients.

CONCLUSIONS

Follow up measurements using MRVL are suitable to assess restenosis after PTA and allow quantifying the grade of recurrent stenosis as well as the hemodynamic consequences.

Does the application of gadolinium-DTPA have an impact on magnetic resonance phase contrast velocity measurements? Results from an in vitro study

INTRODUCTION/OBJECTIVE

To evaluate the potential influence of various concentrations of gadolinium (Gd)-DTPA on magnetic resonance phase contrast (MR PC) velocimetry.

MATERIAL AND METHODS

Imaging was done with a 1.0 T scanner using a standard Flash 2D sequence and a circular polarized extremity coil. In a validated flow phantom with a defined 75% area stenosis different concentrations of Gd-DTPA, diluted in a 10:1 water-yogurt mixture, MR PC measurements were correlated with a Doppler guide wire as gold standard.

RESULTS

MR PC measurements correlated well with the Doppler derived data (r=0.99; P<0.01; maximum pre-stenotic velocity: 21.6+/-0.5 cm/s; maximum intra-stenotic velocity: 81.7+/-0.6 cm/s). Following Gd-DTPA administration no significant (P>0.05; Student's t-test) flow measurement changes were noted (maximum pre-stenotic velocity: 21.3+/-1.3 cm/s; maximum intra-stenotic velocity: 84.0+/-3.6 cm/s). However, delineation of the perfused lumen was enhanced after the application of Gd-DTPA.

DISCUSSIONS AND CONCLUSION

The application of Gd-DTPA does not affect MR PC velocimetry. However, the application of contrast media allowed a more accurate vessel segmentation. MR PC measurements can be reliably carried out after application of Gd-DTPA.

Time-resolved, undersampled projection reconstruction imaging for high-resolution CE-MRA of the distal runoff vessels

Imaging of the blood vessels below the knee using contrast-enhanced (CE) MRI is challenging due to the need to coordinate image acquisition and arrival of the contrast in the targeted vessels. Time-resolved acquisitions have been successful in consistently capturing images of the arterial phase of the bolus of contrast agent in the distal extremities. Although time-resolved exams are robust in this respect, higher spatial resolution for the depiction of tight stenoses and the small vessels in the lower leg is desirable. A modification to a high-spatial-resolution T(1)-weighted pulse sequence (projection reconstruction-time resolved imaging of contrast kinetics (PR-TRICKS)) that improves the through-plane spatial resolution by a factor of 2 and maintains a high frame rate is presented. The undersampled PR-TRICKS pulse sequence has been modified to double the spatial resolution in the slice direction by acquiring high-spatial-frequency slice data only after first pass of the bolus of contrast agent. The acquisition reported in the present work (PR-hyperTRICKS) has been used to image healthy volunteers and patients with known vascular disease. The temporal resolution was found to be beneficial in capturing arterial phase images in the presence of asymmetric filling of vessels.