Numerous craniofacial deformities are characterized by orbital dystopia and anterior skull base deformities. Examples are Crouzon’s syndrome, Apert’s syndrome, coronal and metopic craniosynostosis.
Two concepts developed by Paul Tessier (the father of craniofacial surgery) in the 1960’s are crucial to the understanding of the correction of deformities such as craniosynsostosis. Firstly, the superficial skeleton of the eyesocket comprises what Tessier called the “usable orbit”. It can moved and thus used to put the eyes in a new three dimensional position (correction of dystopia in cases of craniosynostosis). Secondly, the orbit has to be approached from a transcranial route, not from a transfacial one. This enables complete, circumferential exposure of the eyesockets and simultaneous correction of concomitant skeletal problem in the anterior skull base, which often represent the origin of the orbital dystopia.
In the current environment these so called transcranial procedures are performed as conjoint operations of a neurosurgeon, who performs the craniotomy (opening of the skull) and craniofacial surgeon, who completes the orbital osteotomies and reshapes the periorbital skeleton to correct the dystopia. The new position of the orbits is held fixed by bioabsorbable plates and screws (in infants and young children) or titanium plates and screws (older children, adults).
The fronto-orbital advancements represents essentially a 180 to 270 degree osteotomy of both orbits moving them into a more forward position in conjunction with a displacement more towards the nose or towards the ears, depending on the particular case. The resulting bone fragment resembles a diadem or head band, in French “bandeau”.
The correction is usually dramatic, once the “bandeau” has been reshaped and repositioned.