NEW YORK (AP) – For months after Sept. 11, 2001, New York City Fire Chief Stephen King had the same haunting dream: an endless wooden staircase spiraling into the clouds, his friends climbing ever skyward, always beyond his reach.

King was the battalion chief in charge of safety for the New York Fire Department on the morning when 343 firefighters died in the terrorist attack on the World Trade Center. King, who was friendly with nearly half the fire department victims, barely escaped the north tower. His right knee was shattered.

The injured joint slowly healed. His shattered psyche took longer. The veteran of more than 30 years as a firefighter could hardly bear to visit Manhattan, where he had worked for years.

“I didn’t want to even stand next to any high-rise building as long as I lived,” said King, 57, a second-generation fireman with a son now working for the department. “I didn’t even want to go over a bridge.”

King tried sleeping pills, anxiety medications and traditional therapy. But he didn’t get better until he tried virtual reality, pioneered by researchers at Emory University in the early 1990s.

For years, virtual reality has been used to treat common phobias such as a fear of airplanes, storms and speaking in front of crowds. Patients afraid of heights, for example, can learn to cope by putting on a headset with a small screen in front of their eyes, and finding themselves walking across a rope bridge nearly 200 feet above a canyon.

Dr. JoAnn Difede, director of the Anxiety and Traumatic Stress Studies Program at Weill Cornell Medical College, found the practice extremely effective and, after 9/11, thought it could be adapted to treat World Trade Center survivors.

She and other researchers developed a program for patients with post-traumatic stress disorder that incorporated animated 3-D images of the 9/11 attacks. She said she has been treating patients with it for more than a year with very promising results.

The screen in the headset shows patients lower Manhattan, complete with honking traffic and sidewalk chatter, and the World Trade Center twin towers standing twice as tall as everything else.

Early sessions focus just on that peaceful image of the towers against the bright blue sky. Over a period of several months, the program gradually builds to scenes of the planes crashing into the towers and the buildings’ collapse.

Difede said she has treated about two dozen 9/11 survivors with the program and is working to develop a new simulation that takes place inside the towers themselves.

Reliving the day in such vivid detail sounds like it could spark a new round of nightmares. But Difede says it allows patients to become comfortable with their memories.

“This a way to introduce an element of control and to process it emotionally so they’re no longer terrified,” Difede said. “It can then be formed into a memory that’s not associated with terror anymore. It’s just something that’s happened in the past.”

Although most mental health experts agree that the therapy is promising and based on sound research, some have reservations.

“It could be disturbing or upsetting to a fair number of patients,” said Dr. Spencer Eth, a professor of psychiatry at New York Medical College and an expert in post-traumatic stress.

King remembers hearing the thunder of the south tower’s collapse while he was in the tower next door, and remembers believing that he was about to die. “Oh my God, they’re never even going to find my body,” he remembered thinking.

He remembers stumbling out of the building, and rolling down a subway entrance staircase to escape the debris from the second tower’s collapse.

Because of all this, and because he’s “a big, tough fire chief,” he was skeptical of the virtual reality program.

“When I first saw it, I thought this is like a video game for my kids,” he said in his home in Deer Park.

But within 10 minutes of putting on the headset and seeing the twin towers, King said, “My heart was pounding, and I was sweating like I was there.”

The therapy helped him better understand his memories, and has freed him from his nightmares.

“I can function and I couldn’t have ever done that before this treatment,” said King, who had to retire because of his damaged knee.

“I don’t know if I’m exactly the same person as I was before 9/11,” he said. “It’s always going to be part of your life and there’s always going to be something there that makes you different than you were four years ago, but now I’m a functioning person.”

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