Several dozen West Bloomfield High School students not only witnessed an open-heart operation at an Ohio hospital, they did it without leaving their school. They and students from four other high schools in Michigan and Ohio sat in on an open heart surgery Wednesday through an interactive videoconference. Psychologist John Porcerelli said he is not convinced that showing such graphic images to teenagers is wise. \"It is an exciting opportunity if they can deal with it, but there are some adults who can\'t even watch that,\" said Porcerelli, an associate professor at Wayne State University \'s medical school.