Phuc should receive up to seven treatments for her pain and scar tissue over the next nine months, all for free

Vietnamese 'Napalm Girl' Left with Burns on a Third of Her Body Undergoes Laser Treatments to Heal 43-Year-Old Wounds

It’s been 43 years since “napalm girl” Kim Phuc ran screaming through a Vietnamese village, her body burning, and was captured in the center of an award-winning photo. Now she is finally finding relief.

“So many years I thought that I have no more scars, no more pain when I’m in heaven. But now – heaven on earth for me!” Phuc told the Associated Press.

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In September, she received laser treatment for the pain and scar tissue k covers her left arm, and parts of her neck and back, left behind from that day in Vietnam.

Accompanying her was AP photographer Nick Ut, whose 1972 photo of Phuc’s pain, after the South Vietnamese mistakenly dropped napalm on civilians, won a Pulitzer Prize.

(Ut filed his photos of that accident only after he took Phuc to a hospital, according to the AP.)

The laser treatments Phuc is receiving vaporize scar tissue and create “microscopic” holes in the skin, allowing collagen-building medicine to penetrate deeply into the tissue, according to the AP.

More severe burn scars typically need six to nine treatment sessions, the Miami Dermatology & Laser Institute’s Dr. Jill Waibel, who is treating Phuc, tells PEOPLE.

Phuc should see a “substantial” improvement in her pain and physical movement “within days to weeks after each treatment,” as most patients do, Waibel tells PEOPLE via email.

She is a pioneer of this kind of laser treatment, as she explained to PEOPLE in a 2009 story.

“I tell patients it is like boiling water on the stove for tea – you see the steam,” Waibel says. “We are literally vaporizing off the scar tissue: out with the bad skin and then new skin heals the scarred areas.”

Each treatment usually costs up to $2,000, according to the AP. But the institute is doing it for Phuc for free, a spokesperson tells PEOPLE.

Waibel first learned of Phuc’s case after her father-in-law heard Phuc speak at a church a few years ago, she says.

“Kim is a symbol of child victims of war, and hopefully I can give back a little to help ease her suffering and pay it forward,” Waibel says.

The napalm seriously burned more than a third of Phuc’s body in 1972 and left her with scar tissue nearly four times as thick as skin, according to the AP.

She should have died, Waibel told the AP, as other burn victims of that severity had.

For years, Phuc, who has become a noted humanitarian, performed “painful exercises” to preserve mobility. But she is still restricted.

Scarred nerve endings misfire randomly and her pain is most acute as the seasons change, according to the AP. Even carrying a purse on her left side is too much.

But “in the midst of hatred, bitterness, pain, loss, hopelessness,” Phuc relied on her Christian faith, according to the AP.

“No operation, no medication, no doctor can help to heal my heart. The only one is a miracle, [that] God love me,” she said. “I just wish one day I am free from pain.”

In Miami, Phuc told Waibel her pain was a “10 out of 10,” according to the AP. After her first treatment, she gave a fist pump and said, “This was so light, just so easy.”

“She has been gracious, brave and strong during our first treatment,” Waibel says. “I have the honor of working with many scar patients every day – burn, trauma, acne, surgical. And those that do best are like Kim – those who have a positive attitude and are ready to heal.”

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Back home in Canada, where she and her family defected from Vietnam in the ’90s, Phuc looked to a future of healing.

Phuc has seen “some decreased pain already from the first treatment and we expect to see significant improvement with additional treatments over the next few months,” Waibel says.

“Maybe it takes a year,” Phuc, who was traveling Sunday and could not be reached by PEOPLE, told the AP. “But I am really excited – and thankful.”

A longtime goodwill ambassador for the United Nations, Phuc also founded the Kim Foundation International in 1997, to help the child victims of war.

She told CNN this summer that it is her life’s mission, helping orphaned children.

The child in the 1972 photo is “not running anymore,” she told CNN.