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SUMMARY Background High blood flow and low recirculation rates are central for adequate haemodialysis. A new symmetrical tip has been invented promising efficient haemodialysis even if the ports are reversed. Objective To evaluate access recirculation of the 'palindrome' catheter and to report initial experiences in a clinical setting. Material and methods After implantation of the new catheter in 20 patients (male: 14; female: 6; mean age 72 ± 12.2), access recirculation was evaluated using the urea-based recirculation test. After 30 minutes of haemodialysis, ultrafiltration was stopped and arterial and venous samples were taken. Afterwards, the blood flow rate was reduced to 120 ml/min. Another systemic arterial blood sample was taken 10 seconds after the blood pump was switched off. Results All 20 interventions were performed successfully without complications. The average recirculation rate was 8.1% with a median of 2.5% ranging from 0 to 85.8%. Recirculation rates under 5% were measured in 13 patients and more than 10% recirculation were found in two patients. The median of days between catheter implantation and recirculation assessment was the day following implantation. Conclusion The new symmetrical catheter presented low recirculation rates in a clinical setting. Since there is just a single tip, fluoroscopic placement in the right atrium is facilitated. [ABSTRACT FROM AUTHOR]

Percutaneous radiofrequency ablation (RFA) can be as effective as surgical resection in terms of overall survival and recurrence-free survival rates in patients with small hepatocellular carcinoma (HCC). Effectiveness of RFA is adversely influenced by heat-sink effect. Other ablative therapies could be considered for larger tumors or for tumors located near the vessels. In this regard, recent improvements in microwave energy delivery systems seem to open interesting perspectives to percutaneous ablation, which could become the ablation technique of choice in the near future. Microwave ablation (MWA) has the advantages of possessing a higher thermal efficiency. It has high efficacy in coagulating blood vessels and is a relatively fast procedure. The time required for ablation is short and the shape of necrosis is elliptical with the older systems and spherical with the new one. There is no heat-sink effect and it can be used to ablate tumors adjacent to major vessels. These factors yield a large ablation volume, and result in good local control and fewer complications. This review highlights the most relevant updates on MWA in the treatment of small (<3 cm) HCC. Furthermore, we discuss the possibility of MWA as the first ablative choice, at least in selected cases. [ABSTRACT FROM AUTHOR]

Background: Recently different software with the ability to plan ablation volumes have been developed in order to minimize the number of attempts of positioning electrodes and to improve a safe overall tumor coverage.Purpose: To assess the feasibility of three-dimensional cone beam computed tomography (3D CBCT) fusion imaging with "virtual probe" positioning, to predict ablation volume in lung tumors treated percutaneously.Material and Methods: Pre-procedural computed tomography contrast-enhanced scans (CECT) were merged with a CBCT volume obtained to plan the ablation. An offline tumor segmentation was performed to determine the number of antennae and their positioning within the tumor. The volume of ablation obtained, evaluated on CECT performed after 1 month, was compared with the pre-procedural predicted one. Feasibility was assessed on the basis of accuracy evaluation (visual evaluation [VE] and quantitative evaluation [QE]), technical success (TS), and technical effectiveness (TE).Results: Seven of the patients with lung tumor treated by percutaneous thermal ablation were selected and treated on the basis of the 3D CBCT fusion imaging. In all cases the volume of ablation predicted was in accordance with that obtained. The difference in volume between predicted ablation volumes and obtained ones on CECT at 1 month was 1.8 cm(3) (SD ± 2, min. 0.4, max. 0.9) for MW and 0.9 cm(3) (SD ± 1.1, min. 0.1, max. 0.7) for RF.Conclusion: Use of pre-procedural 3D CBCT fusion imaging could be useful to define expected ablation volumes. However, more patients are needed to ensure stronger evidence. [ABSTRACT FROM AUTHOR]

Background: Computed tomography angiography (CTA) is the most employed modality in the follow-up after endovascular aneurysm repair (EVAR) of abdominal aorta (AA); repeated standard controls expose patients to a high cumulative radiation dose (RD).Purpose: To compare image quality and RD between 100 kV and 120 kV protocols in the same group of patients, previously treated with EVAR.Material and Methods: Thirty patients, who had performed a previous CTA at 120 kV, underwent a low dose CTA with the same 64-detector machine. Images were evaluated qualitatively and quantitatively. The influence of body mass index (BMI), considering three groups of patients (normal weight, overweight, and obese) was also assessed. RD values (volume CT dose index and effective dose) were calculated.Results: The mean qualitative score at 100 kV was worse than that at 120 kV, but the difference was not statistically significant and in all cases the image quality was satisfactory. At 100 kV the vessels mean attenuation value was significantly higher; signal-to-noise ratio significantly lower; contrast-to-noise ratio lower, but the difference was not significant. Regarding BMI, the difference in the qualitative score was significant in the obese group, but not in the other two groups; of the quantitative parameters only the signal-to-noise ratio presented a significant difference in the obese group. The average CTDIvol was reduced by 22% and the mean effective dose by 36% with the 100 kV protocol compared to the 120 kV protocol. Both differences were significant.Conclusion: The 100 kV protocol allowed a consistent RD reduction, maintaining a satisfactory image quality in all patients. [ABSTRACT FROM AUTHOR]

Context: There is little reported experience of irreversible electroporation (IRE) of locally advanced pancreatic tumors (LAP). In literature, few data reported complications. In particular vascular vasoconstriction miming splenic infarcts in humans has never been found., Case Report: This report describes the onset of asymptomatic multiple little splenic perfusion defects after the treatment of a LAP localized in the boby-tail portion of the pancreas with the application of five percutaneous probes for IRE, in a 79 year-old man. Splenic artery was regularly patent but entirely trapped in the tumor., Conclusion: To the best of our knowledge, until now, no experience concerning percutaneous IRE of pancreatic cancer described that phenomenon. The cause could not be established with certainty and "vascular lock" may be a valid hypothesis. Additional studies are necessary to evaluate its frequency and its exact pathophysiological cause in humans.

Image-guided thyroid nodule ablation is a relatively new technique for the management of thyroid disease. Notably, if there has been the correct patient selection and if they are performed in high volume centers and via a standardized technique, image-guided thyroid nodule ablation seems to be safe and effective and it can be used to treat thyroid goiters. However, there is still paucity of level 1 evidences and recommendation comparing ablation to surgical or to other non-surgical treatment modalities. Herein, some technical notes for the thyroid nodule ablation to achieve the critical view of safety are presented. Moreover, an additional remark and appraisal from a surgical point of view is described.