The separation of craniopagus conjoined twins is a very rare and complex 
challenge. As with many rare challenges, it presents initially as a deceptively 
simple problem requiring only the most basic clinical techniques. As in many 
reconstructive problems, this paradigm mandates that the neurosurgical team 
performs the separation with the plastic surgeons providing closure at the end 
of the separation. Historically, these approaches have included, as with the 
separation of many other types of conjoined twins, the use of tissue expansion 
before separation followed by separation surgery. In the best hands, at the most 
capable medical centers, the mortality reported in the literature for the past 
50 years is greater than 50%. Craniofacial surgery frequently demands a 
coordinated effort between plastic surgery and neurosurgery and many other 
specializations; separating craniopagus twins takes this coordination to a 
stratospheric level. It is, however, this coordination that is of paramount 
importance. Success clearly requires an understanding of the complex 
interrelationship between the "separation" and the "reconstruction" and that 
decisions made for 1 aspect of the surgery will have a profound impact on 
another aspect of the surgery. The impact can be disastrous or, if planned well, 
can be advantageous.We were contacted to evaluate craniopagus conjoined male 
infant twins for separation. Radiographic studies suggested that the brains were 
separate, and their medical team suggested that they were "fit for separation." 
We reviewed the literature and reviewed our colleagues' experiences with similar 
cases around the world. It became clear that whether separation had been 
unsuccessful or successful, a variety of issues accompanied surgery as follows: 
(1) massive intraoperative hemorrhage, (2) cerebral edema, (3) venous infarcts, 
(4) swelling of flaps, and (5) dehiscence of repairs with cerebrospinal fluid 
(CSF) leak, meningitis, or brain exposure. Although the initial plan was to 
separate the twins in the same fashion as in previous cases (ie, single-stage 
separation surgery preceded by tissue expansion of the scalp), it was clear that 
this approach increases cerebral venous pressure during the separation component 
of surgery and therefore set up a cascade of events favoring failure rather than 
success. Wishing to favor success, we elected to design an open-ended 
multistaged separation to improve venous collateral circulation. We believe that 
this would improve venous drainage, prevent increased venous pressure, diminish 
cerebral edema, and favor the integrity of the dura and flap repair that would 
in turn lessen the risk of CSF leak. The stages would also allow the twins to 
recover from each stage before progressing to the next stage while continuing to 
receive nutritional support and physical therapy. Four major stages for 9 ½ 
months led to their successful separation. There has been no CSF leak or 
meningitis. To our knowledge, this technique has since been applied to 2 other 
sets of craniopagus with similar outcomes.A review of the pertinent literature, 
our rationale, and methodology are discussed in this article.