Computer-assisted midface reconstruction in Treacher Collins syndrome part 2: soft tissue reconstruction

Treacher Collins syndrome (TCS) midfacial involvement associate a skeletal hypoplasia centred on the zygoma to a hypoplasia of all surrounding soft tissues layers and an inferolateral lower lid pseudocoloboma. TCS soft tissue hypoplasia, which has not been well studied, continues to bring challenges in both the indication of surgical treatment and the prediction of their results.

From a standard magnetic resonance imaging (MRI) acquisition, we studied qualitatively and quantitatively the prezygomatic fat compartments and the buccal fat pad of two individuals with TCS whose age were 10 and 14 years. In parallel, we studied 20 controls at the same age to obtain a morphometric database of reference and compare our results. TCS soft tissue involvement was correlated to the results of our prior skeletal involvement study.

The midfacial fat compartments in TCS are severely hypoplastic, especially in the superficial and lateral compartments of the face (all P's < 0.001). No significant correlation existed between the soft tissue and the skeletal involvement.

To our knowledge, this is the first published study of TCS midfacial fat compartments. Their hypoplasia is an important part of the syndrome's facial deformity. The knowledge of their anatomy, organization and volumetric variation is essential. Their re-establishment is key in the early treatment phases of this syndrome. Using the preoperative data, the morphometric database of reference, and surgical simulation, an appropriate surgical technique, going from an autologous fat graft to a free flap, can then be chose.