Hypertelorism correction with facial bipartition and box osteotomy: does soft tissue translation correlate with bony movement?

Objective: Hypertelorism may be corrected by either transcranial box osteotomy or facial bipartition. Despite radical bony resection, the associated soft tissue translation often seems disproportionate. The purpose of this study was to review bony and soft tissue movements in a series of 15 consecutive hypertelorism correction cases. Methods: Two surgical residents in training independently analyzed preoperative and postoperative axial and three-dimensional reconstructed computed tomography data from 15 consecutive patients undergoing facial bipartition (n = 7) or transcranial box osteotomy correction (n = 8) between 2001 and 2010. Anterior interorbital distance, lateral interorbital distance, midpoint globe distance, and globe protrusion were measured along with intercanthal distance and palpebral fissure width. Results: The mean preoperative anterior interorbital distance was 35.5 mm; postoperatively, there was a mean reduction of 9.5 mm, to 26 mm. The mean preoperative intercanthal distance was 48.1 mm; therewas a mean reduction of 10.3 mm, to 37.8mm. The mean preoperative-midpoint globe distance was 69.5 mm; therewas a mean reduction of 9.6 mm, to 59.9 mm. The mean preoperative globe protrusion was 17.6 mm; there was a mean reduction of 5 mm, to 12.6 mm (28.5%). The mean interclass correlation (a measurement of interrater congruency with 1 being complete agreement) was 0.85 Conclusions: Transcranial box osteotomy and facial bipartition correct hypertelorism. The medial canthal tendons, lateral canthal tendons, and globes move in proportion to the bony attachments. We observed a reduction in globe protrusion an average of 29%, therefore risking enophthalmos.