Who are Ben Carson's separated conjoined twins?

During the first Republican debate, Ben Carson discussed his history as a renowned pediatric neurosurgeon. The doctor retired in 2013 to pursue his political ambitions. However, his previous career spanned several decades, and his contributions to the field of pediatric neurosurgery are still visible today. These include the implementation of pioneering technologies such as imaging technology that allows doctors to practice surgeries and the separation of conjoined twins. In 1987, Carson was the first to successfully perform such surgery on Patrick Binder and Benjamin Binder. So who are Ben Carson's separated conjoined twins?

The Binders, twins from Ulm, Germany, underwent separation surgery when they were seven months old. Conjoined twins (or cranial twins), who are usually joined at the skull, rarely live past their second birthday, so this surgery provides an opportunity for Patrick and Benjamin to live longer, healthier lives. The risks of having the surgery were incredible because the twins' brains share a key vein: the superior sagittal sinus, which drains blood and cerebrospinal fluid from the brain. Carson and a team of 70 medical professionals from Johns Hopkins Hospital worked for 22 hours straight to complete the surgery.

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It was during that surgery that Carson began perfecting techniques for slowing down the patient's body to prevent additional medical complications and make it easier to separate shared veins. The twins' blood was drained, their hearts stopped and their brain function was limited. By allowing little, if any, blood to flow through either twin, the risk of fatal blood loss is slightly reduced. The lengthy surgery was still something of a gamble, and ultimately Carson and his team chose not to reconstruct a new skull for each child. Miraculously, despite the brain damage caused by the surgery, the twins survived and continue to live independently. They have since undergone numerous surgeries and are said to be "neurologically normal," according to the Des Moines Register .

Carson continued to perform such surgeries throughout his medical career, including a successful 1997 operation to separate cranial twins joined at the top of their heads and a failed attempt in 2003 to separate adult cranial twins. Not only was Carson the first surgeon to separate twins conjoined at the head, he was also the first to perform the surgery while the children were still in the womb, something he also addressed during the Republican debate.