''What's the most unusual thing, there's no answer,'' said Dr. Carroll B. Lesesne, a plastic surgeon at the hospital. ''After all these investigations, neither the doctors, the hospital or the government agencies have come out and said, 'This is what caused it.' Everybody is worried, 'Could it happen to us?' '' Since the deaths, some Manhattan plastic surgeons said, patients have become more probing about the risks. Robert C. Silich, a plastic surgeon at New York-Presbyterian Hospital, described the impact on his practice as ''tremendous.'' ''I've not had one patient not mention it to me,'' he said, referring to the two deaths, adding that the discussion usually comes up when patients are asked whether they would prefer to have surgery at a hospital or in the doctor's office. ''I'm finding that more people want to be done in the office because they think it's more controlled,'' he said. ''There won't be any residents around -- it will just be me, and I won't have patients in another room.''
