I was thinking that Juliette may have reminded Ben of his mother, who he did have a picture of on-island.

I think Ben would have preferred the surgery on-island to enhance the healing process and not be under the gas in a foreign land but on his beloved island. I like this theory a lot, esp since I think a lot of the Losties had been manipulated for a long time to eventually get to the island, and ben may have had a hand in all of it.