Another set of conjoined twins undergo lengthy separation surgery

In what is expected to be a long and lengthy operation, four-month-old conjoined twin boys have embarked on separation surgery in a hospital in Washington.

The initial surgery is already underway at Washington's Children's Hospital and is likely to last anywhere between 14 to 23 hours say hospital officials.

Mateo and McHale Shaw were born at Washington Hospital Center on May 10th this year and are joined at the lower back, including the tailbone and share portions of their spinal cord.

Parents, Angie Benzschawel and Ryan Shaw, are from Sheboygan, Wisconsin and came to Washington when Benzschawel was 28 weeks pregnant, in preparation for what proved to be an extremely complex Caesarean birth.

A split malformation of the spinal cord has resulted in both children having spina bifida and hydrocephalus, and they were transferred to the Newborn Intensive Care Unit at the Washington Children's hospital shortly after their birth, where they have remained.

An operation was carried out on the baby boys in June to insert tissue expanders under their skin in preparation for the separation surgery.

Neurosurgeons and plastic surgeons have examined the babies to confirm their strategy and the team will spend six to eight hours carefully separating the infants' spinal cords.

They will try to preserve as much of each boy's neurological function as possible and will then spend at least two more hours dividing the shared tailbone and isolating each boy's organs and tissues to complete their separation.

The boys will then be moved into separate operating rooms for the remaining surgery.

At the last report all was going well and the neurosurgeons had exposed the bones of the spine and the dura (lining of the spinal cord), which is considered one of the most complex points of the surgery.

The next step will be to expose the spinal cord and nerve endings, and begin to perform neurophysiologic testing on the boys, sorting out what belongs to who and then separate the spinal cord.

The hospital web site will post updates on the procedures and the boys' condition throughout the day.