"Bingo."
Jayce saw the burning black substance and frowned. He was still sending a steady flow of Life mana into Leah's body, sparing no expense in order to remove the brand in one fell swoop.
The issue was that he had not yet created the spell to Dispel or Cleanse, therefore he would have to try and manipulate the life mana, all while continuing to feel torturous pain through the Empath skill.
While he could very well turn off his Empath skill now that he knew where the brand was located, he wanted to make sure that he was not endangering Leah's life when trying to create the spell. If he felt a huge increase of pain he would know that he did something wrong.
Therefore, he kept it active, trying to keep a hold of his consciousness. After waiting a few moments, Jayce decided there was enough Life mana to be able to make his first attempt at removing the brand.