After Gd-EOB-DTPA injection, most HCCs showed typical arterial enhancement with early washout. Liver-to-lesion contrast was best at 20 minutes.

Portal fields lead to more heat sink than hepatic veins. The effects decreased with the distance between vessel and applicator tip, but less so for portal fields. The 2 vessel types induced considerably different shape alterations of the ablation zones. These results were not dependent on vessel size. This should be considered in the planning of thermal tumor ablations.

Cooling effects of intrahepatic vessels could be simulated in an ex situ model. Cooling effects should be taken into account in RF ablation within 10 mm distance to major liver vessels regardless of blood flow volume or vessel diameter. Surgical RF ablation with temporary blood flow occlusion should be considered in such constellations.

No abstract

Background The fate of magnetically-labeled, barium-gelled Alginate/Protamine Sulfate/Alginate microcapsules (APSA magnetocapsules) following xenotransplantation was assessed by magnetic resonance imaging (MRI) and histopathology. Methods Magnetocapsules with and without human islets were transplanted into 5 different clinically accessible sites of swine: portal vein, subcutaneous tissue, skeletal muscle, the liver and kidney subcapsular space. The surface of APSA magnetocapsules was modified using clinical grade heparin to mitigate an instant blood-mediated inflammatory reaction. Results The accuracy of site-specific delivery was confirmed using a clinical 1.5T MRI setup, where the magnetocapsules appeared as distinct hypointense entities upon transplantation. As proven by the Lee While blood coagulation test, heparin-treated APSA magnetocapsules did not induce blood clotting for more than 48 hours in vitro. However, heparinized magnetocapsules induced innate and adaptive immune responses in vivo regardless of the transplantation site. Conclusions We have demonstrated the feasibility of using a clinical 1.5T magnetic resonance imaging to non-invasively detect the accuracy of APSA magnetocapsule injection into various clinically accessible transplantation sites. Among the investigated transplantation sites, the liver and kidney subcapsular space were found to be the least immune-responsive towards xenografted encapsulated islets.

The system has a high precision and sensitivity under clinical conditions. The segmentation is suitable for portal vein branches of the first and second order and for vessels of >/=3 mm in diameter.

SHU 555 C leads to a significant signal intensity loss of the inflamed bowel wall in T1-, T2- and T2*-weighted images. SHU 555 C enhanced MRI findings correlate well with histologic findings.

: Gadofluorine M-enhanced MR imaging shows a higher correlation of the wall enhancement and histopathology grading in an IBD rat model than does Gd-DTPA-enhanced imaging.