Assessment of orbital volume in frontofacial advancements.

OBJECTIVES

The objective of this study was to evaluate the variation of the orbital volume and the correlation with the magnitude of craniofacial advances as well as demonstrate its effectiveness through comparisons with normal levels of orbital volumes.

INTRODUCTION

Syndromic craniofacial synostosis is characterized by cranial morphological alterations and hypoplasia of the midface that may result in obstructive sleep apnea and exorbitism; these effects are indications of surgical treatment. The gradual advancement of tissues is the surgical treatment to correct accentuated exorbitisms and jaw retrusions.

METHODS

This was a retrospective study by review of medical records and tomographic examinations of 20 patients submitted to distraction osteogenesis between 2001 and 2012, who were divided into 2 groups: groups MB and LF with 11 and 9 patients, who underwent frontofacial or Le Fort III osteotomy. The orbit volume was measured with the InVesalius and Magics software, and facial advancements with Rhinoceros software. Statistical analyses were conducted using Student t test and analysis of variance.

RESULTS

Patients' ages ranged from 6 to 29 years. Group MB showed an increase of 8.94 and 9.84 mm(3) in the right and left orbit volume variation, whereas group LF presented 5.70 and 5.77 mm(3). The average advancements in the right and left orbits were 11.36 ± 3.80 and 11.11 ± 3.45 mm in group LF, respectively, and 14.22 ± 4.12 and 14.48 ± 4.49 mm in group MB.

CONCLUSIONS

Exorbitism was satisfactorily treated. The correlation was proportional in group LF and group MB. There was normalization of orbital volume compared with normal levels of orbital volumes.