Hector Duarte Jr. - All Headline News Staff Reporter

The company says some patients have been harmed because doctors used its Enteryx injection kit incorrectly.

About 3,800 patients have been treated with Enteryx, which was approved by the Food and Drug Administration in 2003.

It is a liquid polymer injected directly into the walls of the esophagus, which then thickens into a permanent spongy lump, helping block acid from flowing from the stomach toward the throat.

Boston Scientific's recall notice says some doctors accidentally punctured the wall of the esophagus while injecting the substance.

According to reports filed with the FDA, patients have suffered leakage, swelling, and ulcers in the esophagus.

An elderly patient died last year after a doctor accidentally hit the wall of the patient's aorta, which prompted the company to issue a safety alert in July 2004.

Boston Scientific sold about $5.5 million worth of Enteryx kits last year.

Dr. Ram Chuttani, chief of endoscopy at Beth Israel Deaconess Medical Center, says his hospital has performed 40 to 50 Enteryx procedures. He describes the process as very demanding from a technical standpoint.