Patrick and Benjamin Binder (born February 2, 1987) were conjoined twins, joined at the head, born in Germany in early 1987, and separated at Johns Hopkins Hospital on September 7, 1987. They were the first twins to be successfully separated by neurosurgeon Ben Carson, of Baltimore, Maryland. For this operation Carson was able to prepare by studying a three-dimensional physical model of the twins' anatomy. Carson described this separation as the first of its kind, with 23 similar attempted separations ending in the death of one or both twins.