Lou Krieger looks down through the lens of a scuba mask and watches the sea life. In the silence of the fish tank, he watches the stingrays' fluttering wings. They come up to swim against him near the surface, their fins sliding over his hands. Like velvet, he thinks.

The sounds of sirens, trucks and gunshots — the noise of war that has stayed with him for almost 50 years — fade. 

Krieger, 68, served as a cryptographer in the Army Security Agency in 1968 and 1969. Since Vietnam, he has coped with substance abuse, uncontrollable rage, flashbacks and lack of sleep.

He petitioned Ripley's Aquarium of Myrtle Beach for permission to use one of their tanks for therapy for veterans suffering from post-traumatic stress disorder after he read an article in The New York Times about a similar program at the Georgia Aquarium in Atlanta. The aquarium agreed. Now, four veterans put on wetsuits and go swimming with sharks and manta rays every other week before the aquarium opens at 9 a.m. 

"It’s the chance for most of us to do something different that we don’t do every day," Krieger said. 

It is difficult to prove what the true benefits of the swims might be. Diving and other out-of-the-box alternatives like it have helped some veterans relax and alleviate their anxiety, at least temporarily. Kieger still suffers from nightmares, but experts say these therapies are positive because they encourage those with PTSD to change their environment and do something team-oriented. 

Mike Hilliard leads similar dives for veterans at the Georgia Aquarium in Atlanta. 

Hilliard, a veteran himself, first tried scuba diving while on vacation with his wife in the Dominican Republic. He remembers rolling backward off a boat and finding himself in a different world.

When he came back up, he said he felt refreshed. He became certified as an open water diver, then as a diving instructor.

"It gave me that adrenaline and that sense of peace and innocence that I’d lost since being in the military," Hilliard said.

By the end of this year, 3,486 veterans will have come through the Atlanta program. Hilliard puts eight veterans in the water at a time. The swims range from 30 to 40 minutes. At Ripley's, four veterans swim for about an hour.

Teamwork is one reason the diving has been effective for participants. Soldiers are taught to rely on a team. Other programs, such as the equine-assisted psychotherapy and therapeutic yoga offered to veterans at The Big Red Barn in Columbia or sailing therapy offered through the Charleston-based Veterans on Deck, provide similar benefits. 

Janina McClain is the assistant clinical director at The Refuge, a clinic in Charleston geared toward patients with PTSD. Rope therapy offered there involves exercises designed to increase trust in others and reduce anxiety.

Those activities are offered in conjunction with exposure therapy and cognitive processing therapy, McClain said.

"They’re learning a new way, and it’s absolutely beautiful to see," she said.

Peter Tuerk, acting director of the PTSD Clinical Team at the Ralph H. Johnson VA Medical Center in downtown Charleston, said activities like diving and rope therapy are not replacements for the tried-and-true methods of treating PTSD. But he doesn't see why they can't help.

There is more evidence for prolonged exposure therapy than any other therapy of its kind, he said. 

In exposure therapy, doctors have the patient repeatedly describe the experience until it "loses its teeth," Tuerk said. He said it's the task of therapists to make patients comfortable with the idea. 

"If there's a lot of people backing away from the treatment, that’s because of the way it’s being discussed," he said.

Rachel Levine, a psychologist at the VA hospital in Charleston, explained how exposure therapy allows people to challenge their beliefs about a traumatic event. 

"Their traumas don’t have to dictate their life," Levine said. "They can dictate their own life in spite of their histories."

Krieger had been coping with PTSD for decades before being diagnosed in 2008. Once he was diagnosed, he said he had a clearer view of his own life and the lives of his relatives who had been in the military.

Back then, veterans were relegated to having "shell shock," he said. Many were drinkers and drug users, like Krieger used to be.

He tried exposure therapy and said he didn't like or benefit from it. For Krieger, the Myrtle Beach PTSD Group, which meets once a week, and the sessions at Ripley's Aquarium, have been effective.

He still has nightmares about twice a week, he said. In the morning, he sits in his garage with a cup of coffee and watches cars go by, ever wary of which belong in the neighborhood and which don't. Many PTSD sufferers are hyper-vigilant. 

New medications have helped. He's been able to wean off of some because of the swims at the aquarium.

His visions of war are still distressing. He said he's lucky to get four to six hours of sleep. But he looks forward to the times he can slide into the cool, soundless depths and let the undulating wings of the stingrays ease his worries, at least for the moment.

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Reach Mary Katherine Wildeman at 843-937-5594. Follow her on Twitter @mkwildeman.

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