Conjoined Twins Profile: Carl and Clarence Aguirre

Twins' names: Carl and Clarence Aguirre.

Birthdate: April 21, 2002.

Hometown: Silay City, The Philippines.

Type of Conjoined Twins: Craniopagus. The boys were joined at the top of the head in a connection similar to Egyptian boys Ahmed and Mohamed Ibrahim. The twins do not share brain tissue, but they do share skull bone, dura mater (the protective lining around the brain), vital blood vessels and the sagittal sinus, a large vein that takes blood away from the brain and carries it to the heart.

Separation Date: In a revolutionary new process, the Aguirre boys were separated in stages, rather than in a marathon non-stop surgery. The first step in the series of separation procedures took place in October 2003, when doctors placed balloons underneath their scalps in a process called tissue expansion. The boys were finally moved apart on August 4, 2004 when surgeons moved apart the adjacent portion of the boys' brains.

Separation Location: Blythedale Children's Hospital, Valhalla, New York and The Children’s Hospital at Montefiore, Bronx, New York (USA)

Separation Team: Joelle Mast, Ph.D., M.D., Chief Medical Officer of Blythedale Children's Hospital
James T. Goodrich, Ph.D., M.D., Chief, Division of Pediatric Neurosurgery, The Children’s Hospital at Montefiore.