Three-dimensional Photogrammetric Analysis of Facial Soft-to-Hard Tissue Ratios After Bimaxillary Surgery in Facial Asymmetry Patients With and Without Sturge-Weber Syndrome.

ABSTRACT

Sturge-Weber syndrome (SWS) is a rare neurocutaneous syndrome characterized by facial port-wine stains. Most patients with facial asymmetry due to SWS have soft and/or hard tissue hypertrophy and require both soft tissue correction and bone surgery. In our experience, because SWS patients are more likely than non-SWS patients to be dissatisfied after bone surgery because of limited soft tissue change, we compared soft tissue changes after bimaxillary surgery between facial asymmetry patients with and without SWS.All patients-5 with SWS and 5 without SWS-underwent bimaxillary surgery by a single surgeon. Soft-to-hard ratios were determined using the preoperative and postoperative vertical lengths from the intersection point between the external orbital contour laterally and the oblique orbital line (LO) to the occlusion line (OL) and the LO to the mandible angle (AG) on cephalography and the distances between the lateral canthus (LC) and oral commissure (OC) and between the LC and soft tissue gonion (Go') on 3-dimensional scanned images.The average change in the [LC-OC] to [LO-OL] ratio was 23.03% ± 10.09% in SWS patients and 88.05% ± 10.44% in non-SWS patients (P = 0.008). The average change in the [LC-Go'] to [LO-AG] ratio was 35.54% ± 15.47% in SWS patients and 78.90% ± 47.56% in non-SWS patients (P = 0.032).Soft-to-hard tissue ratios after orthognathic surgery are significantly smaller in SWS patients than in non-SWS patients. This information is important for preoperative patient counseling, managing patient expectations, enhancing results, and planning the second-stage soft tissue surgery.