When Dr. Jack Vennes of Minnetonka, a gastroenterologist and retired professor for the University of Minnesota School of Medicine, brought back new technology and skills from Japan around 1970, his first thought was to share it with other doctors and educators.

Vennes, who helped develop an imaging procedure at the University of Minnesota and became an authority on it, died Tuesday in St. Louis Park. The longtime Bloomington resident was 84.

"He did more to teach and develop the technique of endoscopic retrograde cholangiopancreatography in the United States than any other one individual," according to a School of Medicine statement.

The procedure, developed by Vennes and Dr. Stephen Silvis, enables physicians to see the bile duct from the liver and the pancreatic ducts, helping in the study of diseases of the pancreas. It offers some treatment of pancreatic cancer. It also allows the diagnosis and cure for bile duct stones.

"The first thing he wanted to do when he returned was to educate physicians and teachers," said Dr. Roger Gebhard, a university professor. "Jack was probably the model educator in gastroenterology in the state of Minnesota. He was a low-key person who had extraordinary procedural skills."

Vennes, who grew up on a dairy farm in Wheeler, Wis., piloted a Navy Avenger torpedo plane over the Pacific during World War II.

In 1947, he got his bachelor's degree at the University of Minnesota and graduated from its medical school in 1951.

Vennes had a private practice in St. Louis Park and began teaching at the university in the mid-1950s, becoming a full professor of medicine in 1976.

Dr. Mike Shaw, a former trainee of Vennes' and an associate clinical professor at the university, recalled medical conferences where "you couldn't walk 5 feet" without an attendee wanting to stop and talk.

Vennes was chosen as one of 50 physicians who had the most impact in their specialty in the 20th century, Shaw said.

Once, a trainee froze after the biopsy he performed caused a hemorrhage. Vennes, off clinical duty at the time, was passing by and helped out. "He realized the trainee needed attention," said Shaw. "He took the time to help him learn from what happened. ... He was just a beloved figure."

Vennes retired in 1993. When he wasn't working or writing medical literature, he spent his time with his family. And he liked to hunt ducks.

"He was patient and could bring out your [best] qualities," said his son David, of Minneapolis.

His wife, Bee Doerr Vennes, died in 2000.

In addition to David, he is survived by another son, Brian of Buffalo, Minn.; a daughter, Martha of Hopkins; a sister, Shirley Rasmussen of Wheeler, Wis.; his former wife, Carol Hocking of Bloomington; stepdaughters Maria Doerr of Minneapolis, Lisa Doerr of Cushing, Wis., and Caroline Doerr of Plymouth, and eight grandchildren.

Services are being planned.