TY - JOUR
T1 - Characterizing the coalescence area of conjoined twins to elucidate congenital disorders in singletons
AU - Boer, Lucas L.
AU - Schepens-Franke, Annelieke N.
AU - Winter, Eduard
AU - Oostra, Roelof-Jan
N1 - Funding Information: We would like to thank Prof. Dirk Ruiter and Drs Elke de Boer for their critical appraisal of the final manuscript. Furthermore we would like to thank Verena Hofecker for the photographs of the specimens from the Narrenturm collection in Vienna (Austria). We thank Drs. Sjaak van Asten and Dr Willemijn Klein for their radiological imaging assistance and expertise. Finally, we would like to thank Drs. Cindy Cleypool for her help in providing the photograph of the specimen from the Bleulandinum collection in Utrecht (The Netherlands). Publisher Copyright: © 2021 The Authors. Clinical Anatomy published by Wiley Periodicals LLC. on behalf of American Association of Clinical Anatomists. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/9
Y1 - 2021/9
N2 - Shared anomalies, always located close to the area of coalescence and observable in virtually every type of conjoined twinning, are currently seen as separate anomalies caused by mostly unknown and seemingly unrelated pathways rather than being connected to the twinning mechanism itself. Therefore, most (case) reports about conjoined twins are mere descriptions of (external) dysmorphologies lacking reflections on the possible origin of their concomitant anomalies. As we will demonstrate in this article, shared anomalies are influenced, and in some cases solely and sequentially explained, by interaction aplasia and neo-axial orientation; two embryological mechanisms to which each set of conjoined twins is subjected and are responsible for their ultimate phenotypical fate. In this review, we consider how the ventral, lateral and caudal conjunction types and their intermediates determine the phenotypic presentation of the twins, including patterns of shared malformations and anomalies, which in themselves can be indistinguishable from those encountered in singleton cases. Hence, it can be hypothesized that certain anomalies in singletons originate in a fashion similar to that in conjoined twins.
AB - Shared anomalies, always located close to the area of coalescence and observable in virtually every type of conjoined twinning, are currently seen as separate anomalies caused by mostly unknown and seemingly unrelated pathways rather than being connected to the twinning mechanism itself. Therefore, most (case) reports about conjoined twins are mere descriptions of (external) dysmorphologies lacking reflections on the possible origin of their concomitant anomalies. As we will demonstrate in this article, shared anomalies are influenced, and in some cases solely and sequentially explained, by interaction aplasia and neo-axial orientation; two embryological mechanisms to which each set of conjoined twins is subjected and are responsible for their ultimate phenotypical fate. In this review, we consider how the ventral, lateral and caudal conjunction types and their intermediates determine the phenotypic presentation of the twins, including patterns of shared malformations and anomalies, which in themselves can be indistinguishable from those encountered in singleton cases. Hence, it can be hypothesized that certain anomalies in singletons originate in a fashion similar to that in conjoined twins.
KW - OEIS
KW - concomitant anomalies
KW - conjoined twins
KW - holoprosencephaly
KW - neural tube defects
KW - sirenomelia
UR - http://www.scopus.com/inward/record.url?scp=85101254809&partnerID=8YFLogxK
U2 - https://doi.org/10.1002/ca.23725
DO - https://doi.org/10.1002/ca.23725
M3 - Article
C2 - 33533057
SN - 0897-3806
VL - 34
SP - 845
EP - 858
JO - Clinical anatomy (New York, N.Y.)
JF - Clinical anatomy (New York, N.Y.)
IS - 6
ER -