A 915-MHz antenna for microwave thermal ablation treatment: Physical design, computer modeling and experimental measurement

A 915-MHz antenna design that produces specific absorption rate distributio ns with preferential power deposition in tissues surrounding and including the distal end of the catheter antenna is described, The design features mi nimal reflected microwave current from the antenna flowing up the transmiss ion line. This cap-choke antenna consists of an annular cap and a coaxial c hoke which matches the antenna to the coaxial transmission line, The design minimizes heating of the coaxial cable and its performance is not affected by the depth of insertion of the antenna into tissue. The paper provides a comparison of results obtained from computer modeling and experimental mea surements made in tissue equivalent phantom materials. There is excellent a greement between numerical modeling and experimental measurement. The cap-c hoke, matched-dipole type antenna is suitable for intracavitary microwave t hermal ablation therapy.