In situ fronto-orbital advancement with medial orbital osteotomies for trigonocephaly-associated hypotelorism.

ABSTRACT

In treating trigonocephaly, the value of direct surgical correction of orbital hypotelorism is controversial. In many cases of hypotelorism, the distance between the orbits increases over time after traditional fronto-orbital advancement. Still, more severe hypotelorism is not fully corrected and may benefit from a more definitive surgical intervention. We describe an in situ fronto-orbital advancement that improves severe hypotelorism and simplifies the surgical treatment of trigonocephaly. The key modification to traditional fronto-orbital advancement is an in situ medial orbital osteotomy that extends along the medial orbit, posterior to the medial canthus, and then across the inferior orbital rim into the piriform aperture. The procedure is indicated only in patients with more severe hypotelorism on physical examination. Rather than creating a freely removable bandeau during the operation, the bone segment composed of the supraorbital bar and superior orbits remains attached at the medial canthi. A midline osteotomy allows the respective orbital segments to be independently mobilized with the medial canthi left attached, and the space between them widened with gentle lateral traction and placement of an interpositional bone graft. Concomitantly, the lateral orbits and lateral supraorbital bar are contoured, advanced, and fixed with resorbable plates and screws. Representative results are shown. In situ fronto-orbital advancement with medial orbital osteotomies is a safe, efficient, and relatively simple technique that results in immediate improvement of hypotelorism and may be a worthwhile maneuver to consider in selected cases.