Bi-directional distraction in the treatment of micro-orbitism: a case report

Correction of micro-orbitism, resulting from clinical or congenital anophthalmia, has traditionally been performed by multiple segmentation of the orbital rim, orbital expanders and orbital conformers. Although distraction osteogenesis is a widely employed surgical approach in the treatment of patients with bony malformations, it has not been employed to enlarge micro-orbits.

The present article describes the development of a new bi-directional orbital distractor to treat a 17-year-old patient affected by micro-orbitism, caused by clinical anophthalmia. The deformity required an internal device to expand and to pull the orbit laterally. Surgical planning and device design were performed by means of patient-specific finite element analysis and a stereolithography model. The surgery consisted of a uni-lateral orbito-malar osteotomy performed via coronal and intraoral access. A 7-day-latency period was observed. The consolidation phase was chosen as six months.

At the end of the distraction process, symmetry of the malar bones and orbital roofs was achieved. During removal of the device, newly formed bone was found at the original osteotomy and distraction gaps.

The reported clinical case suggests that distraction osteogenesis can be a useful procedure for enlargement of micro-orbits. Despite this, a number of questions need to be addressed by long-term follow-up and careful study of future cases.