Two in a Million - Times Three

Abbigail and Isabelle Carlsen

Conjoined twins are extremely rare, occurring once in every 200,000 births. But for nearly a year, caring for conjoined – and formerly conjoined – twins was an everyday reality at Mayo Clinic and its children's hospital.

It began with a call in February 2006 from Jesse and Amy Carlsen of Fargo, North Dakota, whose daughters Abbigail and Isabelle had been born conjoined in November. They spoke with Christopher Moir, M.D., the Mayo Clinic pediatric surgeon who had led teams for two previous successful conjoined twin separations about a decade earlier.

Dr. Moir quickly assembled the leaders of the 70-member team that would care for Abby and Belle during the nearly three months of preparation for their separation. The initial focus was on making sure the girls were growing strong enough for the separation, and on imaging studies to understand their extraordinarily complex and unique anatomy. In early March a team surgically placed inflatable devices under the girls' skin. These were gradually expanded to cause tissue growth, so there would be enough skin to close both girls' abdomens after they were separated.

Meanwhile, the team of specialists continued to meet and study the CT and other imaging to develop the roadmap for the risky and complex operation. In about 60 percent of cases like theirs previously reported in the medical literature, one or both patients had not survived.

Because Mr. and Mrs. Carlsen had previously decided to share their family's story publicly, they came to Mayo Clinic with significant pre-existing news media interest. This news interest continued to grow during the preparation phase, so it seemed the whole world was watching when Abby and Belle were wheeled into surgery on May 12.

After a day-long operation by the 30-member team, which included 18 surgeons, the last tissue connecting Abby and Belle was cut at 4:28 p.m. They still had a long recovery ahead, but on June 6 they said goodbye to the hospital and headed home to Fargo.

Abbygail and Madysen Fitterer

Among those watching the Carlsens' story with particular interest were another North Dakota couple, Stacy and Suzy Fitterer, who had learned that Suzy also was carrying conjoined twins. They also contacted Dr. Moir, and when Abbygail and Madysen were born Aug. 8, they made plans to bring them to Mayo Clinic.

Abbygail and Madysen arrived at Mayo on Sept. 26 and had their operation to insert tissue expanders on Oct. 4. While the basic preparation processes for separating them were similar to the Carlsens' experience, the Fitterer girls presented different challenges because of their unique anatomy.

While Abbygail and Madysen were in the tissue expansion phase, another surprise was in store for the Mayo Clinic team. Valerie James of Mankato, Minn. was touring Mayo Eugenio Litta Children's Hospital on November 9 when she went into labor. Her conjoined twin sons, Jacob and Jordan, were delivered by caesarian section at 30 weeks gestation and were immediately but successfully separated because of the life-threatening way they were joined.

A few weeks later, on January 3, 2007, the Fitterer twins were ready for separation. Their operation didn't take as long as the Carlsens', but their recovery was more difficult. But when they went home to Bismarck on February 22, almost a year to the day after Abby and Belle Carlsen had arrived in Rochester, it capped an extraordinary year at Mayo Clinic.

The Minneapolis Star Tribune had run a three-day series on the Carlsens in the week before their separation, calling them "Two in a Million." Having three sets of these "two in a million" pairs in one year, and with all six children surviving the complex and risky operations, is a unique mark of distinction for Mayo Clinic.