A
Ablation	Removal of tissue through local techniques.
Ablation Zone	The total area receiving the RF treatment at the target temperature, including the tumor and the margin around the tumor.
Alcohol Ablation	Also called percutaneous ethanol injection (PEI). The injection of concentrated alcohol directly into a liver tumor. The alcohol destroys the tumor tissue.
Alternating Current (AC)	The type of current produced by RF generators. Alternating current reverses direction at predictable intervals, called cycles and measured as cycles per second or Hertz (Hz). Standard electrical current alternates at 60 Hz. The human nervous system responds to currents up to 100 kHz (and thus would be damaged by currents in this range). Radiofrequency current is over 200 kHz.
Ascites	Accumulated fluid in the spaces between organs and other tissues in the abdomen.