In this study, researchers from Germany evaluated the efficacy and safety of a new MRI-compatible irrigated laser microcatheter system for thermal ablation of liver metastases.
The microcatheter system consisted of a titanium needle with a diameter of 1.5 mm and a surrounding Teflon catheter with an outer diameter of 1.8 mm (5.5 F).
Initially, the team performed an in vitro laser-induced coagulation of bovine liver tissue to determine the optimal perfusion rate of cooling saline flow, maximum laser energy, and ablation time.
|Overall, ablation of liver metastases was technically and clinically successful.|
|Journal of Magnetic Resonance Imaging|
The researchers then performed laser-induced thermotherapy, using the new microcatheter system, in 28 patients with liver metastases.
Percutaneous insertion and positioning of multiple microcatheters in the lesion, as well as the monitoring of the therapy was performed with a closed high-field MRI scanner. This used a T1-weighted gradient-echo sequences during breath-hold.
The team found that a perfusion rate of 0.75 ml per minute, a laser energy of 15 W, and an ablation time of 20mins were suitable to achieve ablation of the metastatic tissue.
They determined that the mean volume of induced coagulation in vitro was 23.9 ml.
Overall, the research team determined that ablation of liver metastases in patients was technically and clinically successful.
Dr Ralf Puls's team concluded, "The new microcatheter system allows for both catheter placement and monitoring of therapy using a single imaging modality".
"This shortens the procedure and enables more precise puncture and therapy of liver metastases".
"Due to the miniaturized design of the catheter and the real-time monitoring, the procedure is minimally invasive and very well tolerated by patients".
"This new technique seems to be a safe and feasible alternative in treating liver metastases".