"ablation on" or "ablation of"

You can perform an ablation (removal) on the whole of an object:

EP Lab digest From 2004, Vol. 4, No. 7: At Lenox Hill Hospital in New York, they recently performed an ablation on a young gentlemen with WPW syndrome.

But if you want to specify what is being ablated, then it is an "ablation of" something:

1967 Brain 90 256 It appeared that the cortex was involved in the myoclonus itself, as the jerks were abolished by ablation of the motor area.

and this is the most frequent use.

However, please bear in mind that the most frequent use is not necessarily the appropriate use.