Oto vs. Konoha!! (音vs木ノ葉!!, Oto Bāsasu Konoha!!) is chapter 184 of the Naruto manga.
The Sound Four offer to advance Sasuke's cursed seal to its second level. Because they are forcing the process, Sasuke must be put into a death-like state for an extended period of time. They explain the state as 'suspended animation' after which Sasuke agrees and, after "dying", is sealed into a coffin. Meanwhile, Tsunade gives Lee a final chance to back out of the operation. Seeing how determined he is to resume his life as a ninja and fulfil his dreams, she immediately gets to work. As the Sound Four carry Sasuke's coffin to Orochimaru, they are found by Konoha ninja returning from a mission. Knowing they will need help, the Sound Four activate their cursed seals.
The part of Tsunade's conversation with Lee regarding his surgery was moved to episode 107 in the anime.