TY - JOUR
T1 - The craniopagus malformation
T2 - Classification and implications for surgical separation
AU - Stone, James L.
AU - Goodrich, James T.
N1 - Funding Information:
We dedicate this paper to Dr Oscar Sugar, the surgical pioneer of craniopagus separation, and the inspiration behind this effort. His thoughtful approach and warm human qualities remain an example to those fortunate to know him. We also thank Drs Herbert J. Grossman, Theodore S. Roberts, Marion Walker, Willy Lopez, David Staffenberg and Carol Macmillan for helpful insights. Ms Marjorie Brodie was most generous with her time and energy, as were John Fino and Peg Kilmartin. Ms Christa Wellman provided the illustrations, and Ms Tobi McCauley and Ernestine Daniels assisted with preparation of the manuscript. We also appreciate the assistance of Mr Douglas Bicknese of Special Collections at the Library of the Health Sciences, University of Illinois at Chicago. Funding to pay the Open Access publication charges for this article was provided by the Ralph and Marian Falk Foundation.
PY - 2006/5
Y1 - 2006/5
N2 - Craniopagus twins (CPT) are an uncommon, highly fascinating accident of nature. The clinical pathology of this complex entity is reviewed and placed in perspective. A logical classification aids understanding of the anomaly, and is essential to gauge outcome from separation attempts. 'Partial forms' lack significant shared dural venous sinuses (SDVS) and 'Total forms' with SDVS also exhibit more severe compressional brain distortion. Our classification consists of Partial Angular (PA), Partial Vertical (PV), Total Angular (TA) and Total Vertical (TV, formerly O'Connell Types I-III). Total vertical has a continuous cranium, and inter-twin axial facial rotation <40° (Type I), 140-180° (Type II) or intermediate (Type III). The term 'Angular' denotes an inter-twin longitudinal angle below 140°, regardless of axial rotation. Our review categorized 64 well-delineated CPT, including 41 operative separation attempts in small children since initial success in 1952. Just over one-half were TV, almost one-third TA, and partial forms accounted for the remaining one-sixth. About 30% of CPT had shared or fused brain tissue, and a similar percentage of TA twins shared a posterior fossa. Partial forms had significantly higher birth weights, were separated at an earlier age (6 versus 11 months) and had lower mortality and better outcome compared with Total forms. A multi-staged surgical separation for Total CPT had a significantly better mortality than single-staged separation. Discussion emphasizes embryological, anatomical and clinical aspects of the malformation, with emphasis upon obstacles to a successful outcome.
AB - Craniopagus twins (CPT) are an uncommon, highly fascinating accident of nature. The clinical pathology of this complex entity is reviewed and placed in perspective. A logical classification aids understanding of the anomaly, and is essential to gauge outcome from separation attempts. 'Partial forms' lack significant shared dural venous sinuses (SDVS) and 'Total forms' with SDVS also exhibit more severe compressional brain distortion. Our classification consists of Partial Angular (PA), Partial Vertical (PV), Total Angular (TA) and Total Vertical (TV, formerly O'Connell Types I-III). Total vertical has a continuous cranium, and inter-twin axial facial rotation <40° (Type I), 140-180° (Type II) or intermediate (Type III). The term 'Angular' denotes an inter-twin longitudinal angle below 140°, regardless of axial rotation. Our review categorized 64 well-delineated CPT, including 41 operative separation attempts in small children since initial success in 1952. Just over one-half were TV, almost one-third TA, and partial forms accounted for the remaining one-sixth. About 30% of CPT had shared or fused brain tissue, and a similar percentage of TA twins shared a posterior fossa. Partial forms had significantly higher birth weights, were separated at an earlier age (6 versus 11 months) and had lower mortality and better outcome compared with Total forms. A multi-staged surgical separation for Total CPT had a significantly better mortality than single-staged separation. Discussion emphasizes embryological, anatomical and clinical aspects of the malformation, with emphasis upon obstacles to a successful outcome.
KW - Craniopagus twins
KW - Dural venous sinuses
KW - Embryology
KW - Pediatric neurosurgery
KW - Surgery of craniopagus
UR - http://www.scopus.com/inward/record.url?scp=33646247404&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33646247404&partnerID=8YFLogxK
U2 - 10.1093/brain/awl065
DO - 10.1093/brain/awl065
M3 - Review article
C2 - 16597654
AN - SCOPUS:33646247404
SN - 0006-8950
VL - 129
SP - 1084
EP - 1095
JO - Brain
JF - Brain
IS - 5
ER -