title: Bi-directional distraction in the treatment of micro-orbitism: a case report.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: II Maxillo-Facial Surgical Unit, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy. chiara.bellini@polimi.it
authors.forename: Chiara M
authors.initials: CM
authors.lastname: Bellini
authors.forename: Manuela T
authors.initials: MT
authors.lastname: Raimondi
authors.forename: Francesco
authors.initials: F
authors.lastname: Grecchi
mesh_terms: D000293:Adolescent; D000853:Anophthalmos / Q000601:surgery; D017076:Computer-Aided Design; D004867:Equipment Design; D020342:Finite Element Analysis; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D009915:Orbit / Q000002:abnormalities* / Q000601:surgery; D019857:Osteogenesis, Distraction / Q000295:instrumentation / Q000379:methods*; D010027:Osteotomy / Q000379:methods; D010347:Patient Care Planning; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D015050:Zygoma / Q000601:surgery