[Radiologically guided interventional therapies for the treatment of neuroendocrine tumors]

BACKGROUND

The majority of patients with neuroendocrine tumors (NET) develop liver metastases during the course of the disease, significantly impacting prognosis and quality of life.

CLINICAL ISSUE

Radiologically guided interventional therapies, such as thermal ablation, transarterial embolization (TAE)/chemoembolization (TACE), and selective internal radiotherapy (TARE), can play a crucial role in the treatment of metastatic NET.

DATA

Due to the rarity of the disease, the majority of evidence is based on retrospective studies. For thermal ablation, the complete response rates ranging from 31.6 to 95.3% depending on the study. No significant differences in outcomes were found between TAE, TACE, and TARE. In several studies, all intra-arterial procedures led to a reduction of tumor-related symptoms and achieved disease control.

CONCLUSION

Thermal ablation can be used as a curative therapy in oligometastatic patients with nonresectable liver metastases from NETs. In cases of disseminated liver metastases, intra-arterial therapy using TAE, TACE, or TARE can be employed.

[Lesions of the paravertebral mediastinum]

BACKGROUND

Lesions of the paravertebral mediastinum are rare, and knowledge of possible differential diagnoses is essential for clinical practice.

OBJECTIVE/METHODS

To review common lesions of the paravertebral mediastinum.

RESULTS

The paravertebral mediastinum mainly includes fatty tissue and neurogenic structures. Imaging is commonly performed using computed tomography (CT) and magnetic resonance imaging (MRI). Neurogenic tumors are the most common lesions of the paravertebral mediastinum. Other pathologies include extramedullary hematopoiesis, lipomatous, lymphogenic, inflammatory, and cystic lesions. Moreover, also diaphragmatic hernias, vascular and esophageal pathologies may be found in the paravertebral mediastinum.

Simple diameter measurement as predictor of liver volume and liver parenchymal disease

To investigate the accuracy of liver diameters for estimation of liver size and to evaluate their application as tool for assessment of parenchymal liver disease. In the course of a population-based study, (SHIP) one thousand nine hundred thirty-nine volunteers underwent magnetic resonance imaging (MRI) of the liver including 3D gradient echo MRI sequences. Maximum liver diameters were measured in cranio-caudal (CC), anterior–posterior (AP), medial–lateral (ML) orientation. Diameters were compared with true liver volume assessed by liver segmentation. Additionally, age-dependent reference values for diameters were defined. Finally, accuracy of liver diameters was assessed to discriminate volunteers with healthy livers and participants with parenchymal changes, measured by MRI and laboratory. Reference values of liver diameters within the healthy population (n = 886) were defined as follows (mean ± standard deviation, confidence interval CI in cm): CC 17.2 ± 2, CI 13.6/21.2; AP 15.8 ± 1.9, CI 12.6/19.8; ML 19.7 ± 2.3, CI 15.8/24.6. There was a poor correlation using linear regression between liver diameter and true liver volume; CC 0.393, AP 0.359; ML 0.137. The AP direction shows the best correlation to discriminate between healthy and pathologic liver changes; AUC 0.78; p < 0.001, CC AUC 0.53; p < 0.001 and ML AUC 0.52; p = 0.008. Measurement of liver diameter, especially in the anterior–posterior direction is a simple option to detect chronic liver disease but less suitable for prediction of liver volume.

[Preoperative diagnostics and typing of abdominal soft tissue sarcomas]

BACKGROUND

Abdominal sarcomas are a heterogeneous group of rare soft tissue tumors and can be localized intraperitoneally or retroperitoneally. A pretherapeutic differentiated subtyping is essential for planning an individual, multimodal treatment concept in an interdisciplinary team of experts.

OBJECTIVE

The central aspects of histology acquisition, imaging diagnostics and (molecular) pathological subtyping of abdominal soft tissue sarcomas are described in detail.

MATERIAL AND METHODS

Imaging and pathological diagnostics are depicted based on the German S3 guidelines on adult soft tissue sarcomas, a current literature search and personal experiences at the Sarcoma Center at the National Center for Tumor Diseases in Dresden (NCT/UCC).

RESULTS

Preoperative imaging and (molecular) pathological subtyping of abdominal soft tissue sarcomas place high demands on surgeons, radiologists and pathologists. Genome analyses of sarcomas have the potential to identify points of attack for individualized treatment options. The limitations of resectability can only be assessed by experienced sarcoma surgeons at specialized centers.

CONCLUSION

The treatment of abdominal soft tissue sarcomas at an experienced center is associated with a better prognosis. Even at the first suspicion of an abdominal sarcoma, a referral to an experienced center should be made in order to guarantee optimal expertise in diagnostics and treatment.

Long-term outcome of incidental cystic liver tumors in the general population

Aim of this study was to investigate frequency, incidence and risk factors of liver cysts in the general population in a longitudinal survey. Cyst frequency was investigated in 607 adult volunteers (288 women, 319 men, mean age 55 years) using strong T2-weighted magnetic resonance imaging. Risk factors were investigated for occurrence, frequency and size of cystic lesions at baseline. Incidence and physiological growing of the lesions were observed in a 5-years follow-up. At baseline, 431 volunteers had 1,479 cysts (71.0%). The mean number of cysts per person was 3.4 ± 9.0. The mean size of cysts was 13.1 ± 11.7 mm. Women had a higher number of cysts than men (p = 0.026). Older and male volunteers demonstrated a higher cyst frequency (p = 0.002 and p = 0.025). Per one-year increase in age the chance for a liver cyst increased by 2%. Four-hundred seventeen volunteers had cysts in the follow-up, in 24.6% new lesions had occurred. Lesion size significantly increased in follow-up (p < 0.001). Age and male sex were associated with the occurrence of at least one liver cyst. Women had a higher average number of cysts. Cystic lesion progression is a physiological phenomenon in the long-term follow-up.

[Percutaneous biliary and gallbladder interventions]

CLINICAL ISSUE

Percutaneous transhepatic biliary and gall bladder interventions play an important role in the diagnosis and therapy of biliary tract diseases.

PERFORMANCE

With technical success rates up to 99% as well as complications rates up to a maximum of 26% they showed good results. Indications were opacification of the biliary tree as well as treatment of biliary system pathologies, such as drainage and stents.

ACHIEVEMENTS

Interventions were used if endoscopic approaches are not possible or exploited. We describe the current state of knowledge and the range for percutaneous biliary/gall bladder interventions and give an overview of technical approaches for fundamental interventional procedures, including percutaneous transhepatic biliary drainage.

PRACTICAL RECOMMENDATIONS

Percutaneous transhepatic biliary and gall bladder interventions are safe and effective treatments for benign and malignant stenosis, postoperative complications and risk patients with cholecystitis.

Accuracy of ultrasonography in the assessment of liver fat compared with MRI

AIM

To investigate the accuracy of ultrasonography in the assessment of hepatic steatosis using magnetic resonance imaging (MRI) as standard of reference and to explore the influence of additional hepatic iron overload.

MATERIAL AND METHODS

A total of 2,783 volunteers (1,442 women, 1,341 men; mean age, 52.3±13.8 years) underwent confounder-corrected chemical-shift-encoded MRI of the liver at 1.5 T. Proton-density fat fraction (PDFF) and transverse relaxation rate (R2*) were calculated to estimate hepatic steatosis and liver iron overload, respectively. In addition, the presence of hepatic steatosis was assessed by B-mode ultrasonography. The sensitivity, specificity, and accuracy of hepatic ultrasonography were determined for different degrees of hepatic steatosis and different amounts of liver iron.

RESULTS

MRI revealed hepatic steatosis in 40% of participants (n=1,112), which was mild in 68.9% (n=766), moderate in 26.7% (n=297), and severe in 4.4% (n=49) of patients. Ultrasonography detected hepatic steatosis in 37.8% (n=1,052), corresponding to 74.5% sensitivity and 86.6% specificity. The sensitivity of ultrasound increased with the amount of hepatic fat present and was 65.1%, 95%, and 96% for low, moderate, and high fat content; whereas the specificity was constantly high at 86.6%. The diagnostic accuracy of ultrasound for detection of hepatic steatosis did not vary significantly with the amount of liver iron present.

CONCLUSION

Ultrasonography is an excellent tool to assess hepatic steatosis in the clinical setting with some limitations in patients with a low liver fat content. The detection of hepatic steatosis by ultrasonography is not influenced by liver iron.

Comparison of sequential and high-pitch-spiral coronary CT-angiography: image quality and radiation exposure

New protocols for coronary computed tomography angiography (CCTA) could lower the radiation dose for patients but influence the image quality. To compare image quality and radiation exposure in step-and-shoot CCTA and high-pitch spiral CCTA. Fifty-nine pairs of patients matched for weight, height, sex and heart rate were included in this study (74 m, 44 f, average age 60 years, age range 29-94 years). Step-and-shoot CCTA and high-pitch spiral CCTA was performed on a third generation dual-source CT in equally sized patient groups. The signal-to-noise ratio (SNR) in the ascending aorta and the coronary arteries were determined for each dataset. Image quality was rated using a five-point scale. We used the t-test for paired samples to compare SNR and effective dose, and the Wilcoxon test to compare image quality scores. Mean effective dose for the step-and-shoot protocol (4.15 ± 3.07 mSv) was significantly higher in comparison to the high-pitch spiral protocol (1.2 ± 0.69 mSv; p < 0.0001). Mean SNR was higher with the step-and-shoot protocol compared to the high-pitch spiral protocol in the aorta, in the left main and peripheral coronary arteries (p < 0.01), in the proximal right coronary artery (p = 0.027). Image quality scores were significantly better for the step-and-shoot protocol (p = 0.0003). Step-and-shoot CCTA has significantly better SNR and overall image quality compared to high-pitch spiral CCTA, but with a mean effective dose more than thrice as high.

Management of clinically relevant postpancreatectomy hemorrhage (PPH) over two decades - A comparative study of 1 450 consecutive patients undergoing pancreatic resection

BACKGROUND/OBJECTIVES

PPH is the main cause of mortality (up to 50%) after pancreatic resection. Due to differences in time of onset, localization and clinical impairment, there is no consistent management algorithm.

METHODS

Between 1994 and 2014 the occurrence of PPH in 115 out of 1 450 patients from a prospectively collected database was analyzed. The cohort was divided into two time periods: 1994-2009 and 2010-2014. The differences between the two groups were analyzed.

RESULTS

The overall incidence of PPH was 7.9%. The main causes of hemorrhage were the pancreatic anastomosis (31.1%) and the splanchnic arteries (23.5%). In the first period, there were more anastomotic hemorrhages (40.0% vs. 20.4%, p = 0.02), while in the second period more hemorrhages from the splanchnic arteries occurred (12.3% vs. 37%, p = 0.002). Bleeding control was achieved by relaparotomy (45.7%), noninterventionally (22.8%), endoscopically (19.7%) and angiographically (13.4%). In the second period, the relevance of interventional angiography significantly increased (24.6% vs. 4.3%, p = 0.001), whereas endoscopy lost importance (7% vs. 30%, p = 0.001). The in-hospital case fatality rate after PPH was 27.4%, with higher case fatality rate following extraluminal hemorrhage (23.9% vs. 3.4%, p < 0.001).

CONCLUSIONS

A shift in the management of PPH could be seen over the two periods. Interventional angiography has gained more importance in the treatment of severe extraluminal hemorrhage of the splanchnic arteries. Adequate treatment of PPH is crucial to improve the outcome.

Cirse Quality Assurance Document and Standards for Classification of Complications: The Cirse Classification System

Interventional radiology provides a wide variety of vascular, nonvascular, musculoskeletal, and oncologic minimally invasive techniques aimed at therapy or palliation of a broad spectrum of pathologic conditions. Outcome data for these techniques are globally evaluated by hospitals, insurance companies, and government agencies targeting in a high-quality health care policy, including reimbursement strategies. To analyze effectively the outcome of a technique, accurate reporting of complications is necessary. Throughout the literature, numerous classification systems for complications grading and classification have been reported. Until now, there has been no method for uniform reporting of complications both in terms of definition and grading. The purpose of this CIRSE guideline is to provide a classification system of complications based on combining outcome and severity of sequelae. The ultimate challenge will be the adoption of this system by practitioners in different countries and health economies within the European Union and beyond.

Technical Description, Phantom Accuracy, and Clinical Feasibility for Single-Session Lung Radiosurgery Using Robotic Image-Guided Real-time Respiratory Tumor Tracking

To describe the technological background, the accuracy, and clinical feasibility for single session lung radiosurgery using a real-time robotic system with respiratory tracking. The latest version of image-guided real-time respiratory tracking software (Synchrony®, Accuray Incorporated, Sunnyvale, CA) was applied and is described. Accuracy measurements were performed using a newly designed moving phantom model. We treated 15 patients with 19 lung tumors with robotic radiosurgery (CyberKnife®, Accuray) using the same treatment parameters for all patients. Ten patients had primary tumors and five had metastatic tumors. All patients underwent computed tomography-guided percutaneous placement of one fiducial directly into the tumor, and were all treated with single session radiosurgery to a dose of 24 Gy. Follow up CT scanning was performed every two months.

All patients could be treated with the automated robotic technique. The respiratory tracking error was less than 1 mm and the overall shape of the dose profile was not affected by target motion and/or phase shift between fiducial and optical marker motion. Two patients required a chest tube insertion after fiducial implantation because of pneumothorax. One patient experienced nausea after treatment. No other short-term adverse reactions were found. One patient showed imaging signs of pneumonitis without a clinical correlation.

Single-session radiosurgery for lung tumor tracking using the described technology is a stable, safe, and feasible concept for respiratory tracking of tumors during robotic lung radiosurgery in selected patients. Longer follow-up is needed for definitive clinical results.

[Diagnosis of and therapy for hepatocellular carcinoma]

The interdisciplinary guidelines at the S3 level on the diagnosis of and therapy for hepatocellular carcinoma (HCC) constitute an evidence- and consensus-based instrument that is aimed at improving the diagnosis of and therapy for HCC since these are very challenging tasks. The purpose of the guidelines is to offer the patient (with suspected or confirmed HCC) adequate, scientifically based and up-to-date procedures in diagnosis, therapy and rehabilitation. This holds not only for locally limited or focally advanced disease but also for the existence of recurrences or distant metastases. Besides making a contribution to an appropriate health-care service, the guidelines should also provide the foundation for an individually adapted, high-quality therapy. The explanatory background texts should also enable non-specialist but responsible colleagues to give sound advice to their patients concerning specialist procedures, side effects and results. In the medium and long-term this should reduce the morbidity and mortality of patients with HCC and improve their quality of life.

Multimodality treatment for early-stage hepatocellular carcinoma: a bridging therapy for liver transplantation

PURPOSE

To evaluate the efficiency of a multimodality approach consisting of transcatheter arterial chemoembolization (TACE) and radiofrequency ablation (RFA) as bridging therapy for patients with hepatocellular carcinoma (HCC) awaiting orthotopic liver transplantation (OLT) and to evaluate the histopathological response in explant specimens.

MATERIALS AND METHODS

Between April 2001 and November 2011, 36 patients with 50 HCC nodules (1.4-5.0 cm, median 2.8 cm) on the waiting list for liver transplantation were treated by TACE and RFA. The drop-out rate during the follow-up period was recorded. The local efficacy was evaluated by histopathological examination of the explanted livers.

RESULTS

During a median follow-up time of 29 (4.0-95.3) months the cumulative drop-out rate for the patients on the waiting list was 0, 2.8, 5.5, 11.0, 13.9 and 16.7% at 3, 6, 12, 24, 36 and 48 months, respectively. 16 patients (with 26 HCC lesions) out of 36 (44.4%) were transplanted by the end of study with a median waiting list time of 13.7 (2.5-37.8) months. The histopathological examination of the explanted specimens revealed a complete necrosis in 20 of 26 HCCs (76.9%), whereas 6 (23.1%) nodules showed viable residual tumor tissue. All transplanted patients are alive at a median time of 29.9 months. Imaging correlation showed 100% specificity and 66.7% sensitivity for the depiction of residual or recurrent tumor.

CONCLUSION

We conclude that TACE combined with RFA could provide an effective treatment to decrease the drop-out rate from the OLT waiting list for HCC patients. Furthermore, this combination therapy results in high rates of complete tumor necrosis as evaluated in the histopathological analysis of the explanted livers. Further randomized trials are needed to demonstrate if there is a benefit in comparison with a single-treatment approach.

Diagnosis, therapy monitoring and follow up of renal artery pseudoaneurysm with contrast-enhanced ultrasound in three cases

PURPOSE

We describe the presentation of renal artery pseudoaneurysm (RAP) in different imaging modalities (CT, DSA, standard US, contrast enhanced ultrasound (CEUS)). In particular the benefit of CEUS with regards to therapy monitoring and follow up care shall be highlighted.

MATERIALS AND METHODS

Three patients with renal artery pseudoaneurysm after renal surgery were investigated with CT and/or US (grey-scaled US, color duplex US, CEUS), respectively. The therapy (angiography-coiling) was monitored using contrast-enhanced ultrasound.

RESULTS

Accurate diagnosis of RAP in our study was yielded using color duplex US and CEUS. CEUS was very practical for therapy monitoring of coil embolization with the potential of shortening the invasive DSA. Thus, CEUS has potential of radiation dose reduction and the potential of saving coils with the result of cost reduction.

CONCLUSION

CEUS is an appropriate approach for monitoring coil embolization of RAP.

Practical vascular anatomy in the preparation of radioembolization

As the incidence of primary and metastatic liver cancer continues to increase, the use of minimally invasive techniques as a treatment option is becoming more common. Radioembolization, a form of intra-arterial brachytherapy, is a technique where particles of glass or resin, impregnated with the isotope 90yttrium (90Y), are infused through a catheter directly into the hepatic arteries. This modality is based on the fact that hepatic malignancies receive their blood supply from the hepatic artery, whereas normal hepatocytes are perfused mostly from the portal circulation, which allows delivery of high doses to the tumor vasculature with relative sparing of normal liver tissue. This has been shown to be effective for both primary and metastatic tumors. A variety of complications may be related to hepatic intra-arterial treatments, especially to the gastroduodenal region. These complications are known to come from inadvertent extrahepatic infusion of 90Y particles, through arteries originating from the hepatic arterial branches such as the falciform artery, cystic artery, arteries from the pancreaticoduodenal arcade, gastroduodenal artery, or right gastric artery. Surgeons and interventional radiologists rely on accurate imaging and assessment of the hepatic arterial supply. It is important to know the common anatomic variations and technical considerations before radioembolization. We recommend an aggressive occlusion of all the above-mentioned arteries; further, clinicians should watch out for any other aberrant branches, and if in doubt, they ought to be coiled.

FDG-PET-CT and whole-body MRI for triage in patients planned for radioembolisation therapy

PURPOSE

The purpose was to evaluate the potential of FDG-PET-CT and whole-body MRI (WB-MRI) as diagnostic triage methods for patients planned for radioembolisation of metastatic liver disease.

MATERIALS AND METHODS

135 patients with multifocal liver metastases were evaluated for potential palliative therapy with radioembolisation using 90-Yttrium microspheres. All patients were examined consecutively with FDG-PET-CT and WB-MRI for exclusion of relevant extra-hepatic tumor manifestations. All patients underwent 99mTc-albumine angiography followed by scintigraphy to exclude significant hepato-pulmonary shunting.

RESULTS

Out of the 135 patients included into the pre-therapeutic diagnostic algorithm, 56% were eligible and received radioembolisation, while 44% could not be treated. In 91% the exclusion criteria was diagnosis of significant extra-hepatic metastatic disease. In 85% exclusion diagnosis was made concordantly by both FDG-PET-CT and WB-MRI, in 9% diagnosis was provided by PET-CT, in 6% by WB-MRI alone. Patient-based sensitivity for detection of extra-hepatic disease was 94% for PET-CT and 91% for WB-MRI. False-positive diagnosis of extrahepatic disease leading to exclusion for radioembolisation therapy was made in 2% of patients, in one patient by PET-CT and in one patient by WB-MRI alone. Overall, specificity for inclusion of radioembolisation therapy by combining both modalities was 99%. In 9% of patients angiographic diagnosis made radioembolisation impossible, in 7% solely the angiographic findings were decisive.

CONCLUSION

Both FDG-PET-CT and WB-MRI are efficient diagnostic triage methods for patients planned for radioembolisation of liver metastases. Overall, FDG-PET-CT shows a trend to higher diagnostic accuracy compared to WB-MRI and may be used as imaging method of choice as a standalone examination. In combination, both modalities exhibited high sensitivity for the diagnosis of extra-hepatic tumor manifestations and result in high specificity.

Tauroursodeoxycholic acid reduces endoplasmic reticulum stress, trypsin activation, and acinar cell apoptosis while increasing secretion in rat pancreatic acini

Endoplasmic reticulum (ER) stress leads to accumulation of un- or misfolded proteins inside the ER and initiates the unfolded protein response (UPR). Several UPR components are physiologically involved in pancreatic development and are pathophysiologically activated during acute pancreatitis. However, the exact role of ER stress in exocrine pancreatic acini is mainly unclear. The present study examined the effects of tauroursodeoxycholic acid (TUDCA), a known ER chaperone, on acinar function and UPR components. Isolated rat pancreatic acini were stimulated by increasing concentrations of cholecystokinin (CCK-8) with or without preincubation of TUDCA. UPR components were analyzed, including chaperone binding protein (BiP), protein kinase-like ER kinase (PERK), X-box binding protein (XBP)-1, c-Jun NH(2)-terminal kinase (JNK), CCAAT/enhancer binding protein homologues protein (CHOP), caspase 3 activation, and apoptosis. In addition, TUDCA effects were measured on amylase secretion, calcium signaling, trypsin, and cathepsin B activation. TUDCA preincubation led to a significant increase in amylase secretion after CCK-8 stimulation, a 50% reduction of intracellular trypsin activation, and reduced cathepsin B activity, although the effects for cathepsin B were not statistical significant. Furthermore, TUDCA prevented the CCK-8-induced BiP upregulation, diminished PERK and JNK phosphorylation, and prohibited the expression of CHOP, caspase 3 activation and apoptosis. XBP-1 splicing was not altered. ER stress response mechanisms are activated in pancreatic inflammation. Chemical chaperones enhance enzyme secretion of pancreatic acini, reduce ER stress responses, and attenuate ER stress-associated apoptosis. These data hint new perspectives for an employment of chemical chaperones in the therapy of acute pancreatitis.

Comparison of time-resolved CT-angiography, contrast-enhanced ultrasound and digital subtraction angiography in a patient with a small type II endoleak after endovascular aneurysm repair

We report discordant imaging findings of a small persistent type II endoleak in a 72-year-old man who had undergone endovascular aneurysm repair (EVAR) of an abdominal aortic aneurysm. Although the aneurysm was growing in size digital subtraction angiography could not detect an endoleak, but time-resolved CT-angiography and contrast enhanced ultrasound did detect a small type II endoleak.

Radiofrequency ablation after selective internal radiation therapy with Yttrium90 microspheres in metastatic liver disease-Is it feasible?

This retrospective study analyzes, whether patients suffering from extensive hepatic metastatic disease treated with SIRT can become suitable candidates for RFA.Within 38 months 46 patients (26 female, 20 male; age 32-75 years) bearing an extensive hepatic metastatic disease were treated with SIRT. Patients suffered from metastases of breast cancer (16/46), colorectal cancer (CRC) (21/46), neuroendocrine (3/46), and other primary carcinomas (6/46). The indication for SIRT was otherwise untreatable metastases confined to the liver. Forty-three patients received single-session whole-liver radioembolization treatment using Yttrium90 resin microspheres with a mean activity of 2.13GBq. In 1 patient SIRT was confined to the left and in 2 patients to the right liver lobe. In 3 patients major complications (2/3 gastric ulceration and 1/3 oedematous pancreatitis) and in 24 patients minor complications occurred (acute abdominal/epigastric pain and/or nausea). Follow-up CT and/or MRI were obtained in 44 of 46 patients. In 5 of 44 patients tumor load decreased substantially (3/5 breast cancer, 1/5 CRC and 1/5 pancreatic cancer) making RFA feasible. The patients were referred for RFA after the first 3-month follow-up. RFA of the liver was successful in all cases in terms of complete ablation. In selected patients radioembolization is able to downstage liver metastases to an extent making a subsequent RFA suitable and therefore allows increasing the number of patients with a "complete response" after a minimally invasive therapy.

[Therapy response of liver tumors after selective internal radiation therapy]

Selective internal radiation therapy (SIRT) is used for the treatment of patients with liver tumors, especially for those with hepatocellular carcinoma (HCC) or liver metastases from various primary tumors. Currently this innovative treatment concept is recommended when established state-of-the-art treatment regimes have failed and tumor progression is noted or if the treatment has to be abandoned because of intolerable toxic effects. For SIRT small biocompatible microspheres (SIR-Spheres(R)) are labelled with the radioactive isotope 90Yttrium, a pure beta emitter, and are superselectively infused into the hepatic arteries. The microspheres are collected in the precapillary vessels in and surrounding the tumor. The beta radiation of 90Yttrium has an average penetration in tissue of approximately 2.5 mm and results in very high doses of radiation being selectively targeted to metastases providing protection to the surrounding healthy liver tissue. In this paper we review the results of SIRT in patients with hepatic metastases from colorectal cancer, breast cancer, neuroendocrine tumors and primary liver cancer (HCC).

Vertebroplasty in the treatment of osteoporotic vertebral body fracture

During the last few years, vertebroplasty has gained a wide acceptance for the treatment of painful osteoporotic vertebral body fractures and osteolytic changes. However, new guidelines with significant changes in indications and technique were published recently in Europe. Therefore, the aim of this review is to highlight recent changes in indications for vertebroplasty, patient work-up and changes in procedural technique, and to give an overview of patient outcome and possible complications. Therefore, technical details like different types of fluoroscopy, needle placement, pain management during the intervention, recommended equipment, including bone cement, and the use of venography are discussed. Postprocedural issues are noted, including the risk of minor and major complications and the expected outcome of the treated patients.

Percutaneous vertebroplasty in tumoral osteolysis

Percutaneous vertebroplasty is a minimally invasive, radiologically guided procedure in which bone cement is injected into structurally weakened or destructed vertebrae in order to achieve additional biomechanical stability. In addition to treating osteoporotic vertebral fractures, this technique gains popularity to relieve pain by stabilizing vertebrae compromised by, for example, metastases, aggressive hemangiomas or multiple myeloma that are at risk of pathologic fracture. Since conservative treatment with narcotic analgesics, bed rest, biphosphonates and back bracing for several weeks is often ineffective and the analgesic effect of radiation therapy is delayed, percutaneous vertebroplasty may play a beneficial role in the management of metastases to the spine.

[Ultrasound diagnosis of vascular complications following transfemoral puncture]

Percutaneous catheter interventions are performed increasingly often for the purposes of both diagnosis and therapy. The incidence of local complications reported after transfemoral catheterization in the literature is 0.1-9%. Such complications should be detected as early and reliably as possible, and sonography is a good means of finding them during follow-up, not least because it is suitable for use in examinations at the bedside. The clinical value of sonography compared with other examination techniques is made clear with reference to specimen cases.