At approximately what temperature does irreversible cellular death occur during RF ablation?

• A. 40°C
• B. 50°C
• C. 60°C
• D. 70°C

Answer: (B)

During RF ablation, what determines whether cells die permanently is the temperature they reach and how long that heat is applied. When tissue heats to around 50°C, proteins denature and cell membranes lose integrity in a way that the damage becomes irreversible, leading to coagulative necrosis. The exact outcome also depends on exposure time—the higher the temperature, the shorter the time needed, but the conventional lethal threshold is about 50°C. Lower temperatures, like 40°C, tend to cause reversible changes if cooling or short exposure occurs, while much higher temperatures cause rapid coagulation, but the standard question’s focus is the approximate lethal threshold, which is about 50°C.