Modeling liver electrical conductivity during hypertonic injection.

Area of Science:

• Medical physics
• Gastroenterology
• Oncology

Background:

• Liver metastases are challenging to treat with surgery or ablation due to scattered nodules.
• Irreversible electroporation (IRE) offers a potential solution for widespread liver tumors.
• IRE requires increased electrical conductivity in liver tissue, which can be achieved by injecting hypersaline solutions.

Purpose of the Study:

• To develop and validate a mathematical model for predicting liver conductivity changes after hypersaline injection.
• To assess the feasibility of increasing global liver conductivity using hypersaline fluids via portal vein injection.

Main Methods:

• A mathematical model was created, integrating pharmacokinetic and saline injection models, accounting for blood viscosity changes.
• A pilot study in pigs involved injecting 20% NaCl solution (100-200 mL) at varying flow rates (53-171 mL/min) through the portal vein.
• In vivo electrical conductivity measurements were taken and compared with model predictions.

Main Results:

• The mathematical model accurately predicted NaCl distribution and conductivity changes in the liver.
• In vivo measurements in pigs validated the model's quantitative and qualitative predictions.
• A maximum conductivity increase of 4 times the basal level (0.44 S/m) was achieved, with a 14.6% average relative error from the model.

Conclusions:

• The developed mathematical model effectively predicts liver conductivity changes during hypertonic saline injection.
• This approach shows promise for enhancing IRE efficacy in treating liver metastases by increasing tissue conductivity.
• The findings support the potential of hypersaline infusion for improving liver tumor ablation techniques.