Correction of Hypertelorism: Surgical Results Related to Three Dimensional Planning Assessments in Various Orbital Dystopias

The aim of this study about correction of hypertelorism was to test the hypothesis whether there is a predictable relationship between a three dimensional planning assessment for soft tissue changes as well as for movements of the osseous orbits or the occular globes and the surgical outcome. From 1996 to 1999 five patients (mean age 11 years, ranging from 5 to 35) underwent hypertelorism surgery in our clinic by combined intra- and extracranial approach. Scheme for surgery was calculated by a digital three dimensional computed tomographic (CT) scan model. Soft tissue distances were measured clinically. Bony conditions were evaluated pre- and postoperatively by three dimensional CT-scans. There was a strong correlation between bony structures in the digital predicition model and postoperative CT-scans. With reference to the bony reduction of intraorbital distance we found only a moderate correlation between intercanthal distance in the digital model and postoperative CT-scans or postoperative clinical measurement. Correlations between the digital model and postoperative CT-scans were stronger in vertical than in transversal movements of the orbits. We conclude that digital three dimensional planning assessment is a useful predictor in hypertelorism surgery not only for the bony outcome. Keywords: hypertelorism, computer assisted 3D planning