Successful Operation Separating Craniopagus Twins Utilizes Multi-staged Approach

Newswise — Cases of craniopagus (head-to-head) conjoined twins number only one in 10,000,000 births. Survival rates are low -- 78 percent of craniopagus twins die by the time they reach age 1, and 90 percent die by the time they reach age 10. Until the 1950s, there were no survivors in twin separation surgery. The first double-twin survival was recorded in 1957, but with serious medical implications. Up until the 1980s, it was common to lose one or both children secondary to blood loss and surgical complications. It is common for there to be other significant complications such as infection, cerebrospinal fluid leaks, hydrocephalus, and severe neurological injury to one or both children.

James T. Goodrich, MD, PhD and David Staffenberg, MD led the multi-disciplinary medical team at the Children's Hospital at Montefiore Medical Center in this staged twin separation. This was the first time ever that a double separation was performed without the need for immediate additional surgery and with no immediate signs of neurological impairment or deficit. The details of this groundbreaking surgery, "The Induction of Venous Collateral Circulation by Staged Separation of Craniopagus Twins," will be presented by James T. Goodrich, MD, 4:00 to 4:15 p.m. on Monday, April 18, 2005, during the 73rd Annual Meeting of the American Association of Neurological Surgeons in New Orleans. Co-authors are James L. Stone, MD, Willy Lopez, MD, Allan L. Brook, MD, Jacqueline A. Bello, MD, and Fady Charbel, MD.

The neurosurgeons were first introduced to the Filipino Aguirre twins, Carl and Clarence, when they were 11-months old in March 2003. A six-month assessment was done on the twins, in conjunction with Willy Lopez, MD at the University of the Philippines, Manila, before they arrived in New York in September 2003. Initially, the boys were at 60 percent of their normal body weight, and both had fairly severe aspiration pneumonias from swallowing food into their lungs. After stabilizing the boys nutritionally, the team began a staged separation, in the hopes of getting Carl to develop his own deep venous drainage circulation. Clarence clearly owned and used the majority of the outflow venous return from the brain. "A single stage separation would have caused irreparable harm to Carl, possibly costing him his life, and if he survived, there would have been a very high chance of severe neurological damage," explained Dr. Goodrich.

In October of 2003, the team started the first of four staged separations. During each operation, a craniotomy was performed, in which a small section of the skull was removed, exposing the upper surface of each boys' head. Bridging veins between the two children were tied off. At surgery, a vein would be identified, clamped and observed. If after several minutes no swelling occurred and the brain retained its normal color, i.e., did not look like it was going to stroke, then the vein or veins were tied off. "Tying off shared veins was a necessary step prior to physically separating the twins, because at separation, they would need completely independent blood vessel systems," said Dr. Goodrich.

Subsequent stages were carried out in November 2003, February 2004, and the final stage on August 4-5, 2004. "The riskiest operation was the third one in February 2004. There were two major shared veins that had to be tied off -- part of the sagittal sinus -- an abnormal network of shared veins that formed what appeared to be a 'pool' of blood between the boys' brains. The sagittal sinus is key to the drainage of blood from the brain back to the heart. Without sufficient independent drainage and blood circulation, neither boy would survive," stated Dr. Goodrich.

"The big surprise came at the final separation, when we encountered conjoined or fused brains between the two boys. All of our work up to that point had suggested the brains abutted but were not necessarily joined. Carl's right parietal lobe was joined to Clarence's left parietal lobe over an area of approximately 3-4 cm. It is quite likely the boys were using this conjoined brain as a 'hardwiring' and a point of communication between each other. Before the final surgery, we had noted little verbal communication between the two, yet when they moved there was a good deal of synchrony between them, and behaviors that can now be more easily explained, realizing the existence of the conjoined brain," remarked Dr. Goodrich. During the 17-hour operation, the team selected the most "embryologically appropriate" site midway along the fused brain tissue to divide the twins. They reconstructed the dura mater, the sac of tissue that lines the brain, for each boy individually, using artificial tissue.

"The boys' postoperative courses have been most uneventful, with no significant neurological injury detected in either of them. Cognitive function has been excellent, with no setbacks. The staging clearly allowed both boys to adjust to separate vascular circulations. The main concern now is continuing to improve their motor skills and reverse the effects of nearly 2 1⁄2 years of being confined to lying solely on their backs. They can celebrate two birthdays -- the day they were born in April 2002, and their second birthday on the day they were separated, August 4, 2004," added Dr. Goodrich.

Founded in 1931 as the Harvey Cushing Society, the American Association of Neurological Surgeons (AANS) is a scientific and educational association with over 6,800 members worldwide. The AANS is dedicated to advancing the specialty of neurological surgery in order to provide the highest quality of neurosurgical care to the public. All active members of the AANS are Board-certified by the American Board of Neurological Surgery, the Royal College of Physicians and Surgeons of Canada, or the Mexican Council of Neurological Surgery, A.C.