Wayne Weaver had always maintained a steady weight throughout his life, so when he began dropping pounds in fall 2014, he knew something was wrong, CBS DFW reported.

“I wasn’t able to eat the normal amount of food because my esophagus was telling me it wouldn’t take any more in,” 79-year-old Weaver, a great-grandfather who lives in Irving, Texas told the news channel.

Weaver ended up being diagnosed with achalasia, a relatively rare condition that renders the esophagus immobile. The esophagus is the muscular tube that extends from the neck to the abdomen, connecting the throat to the stomach, and is essential for eating and drinking.

According to the Cleveland Clinic, the lower esophageal sphincter (LES), the valve at the end of the esophagus, stays closed when an achalasia patient swallows, which results in the backup of food.  In addition to weight loss, heartburn, chest pain and vomiting undigested food are symptoms of the condition. Scientists don’t know for sure what causes achalasia, as it isn’t genetic, but they believe a virus may be to blame.

Achalasia usually occurs in the elderly but sometimes is diagnosed in younger people. It affects an estimated 3,000 Americans every year, according to the Cleveland Clinic.

By the time Weaver had lost 17 pounds, he sought care from Dr. Steven Leeds, a minimally invasive surgery specialist at Baylor University Medical Center in Dallas.

In late January, Leeds performed surgery on Weaver by using a tiny camera to evaluate his esophagus.

“We get to the esophagus, and cut that muscle and relieve that pressure, which allows things to pass,” Leeds told the news station.

According to the Cleveland Clinic, minimally invasive surgery is one of four main treatments for achalasia. The others are surgery, balloon dilation and medication.

After Weaver underwent his procedure, he spent one night in the hospital and didn’t have any post-surgery discomfort. He told CBS DFW that he now feels like himself again, has returned to his normal weight, and is eating regularly and easily again.

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