title: Evaluation of the application of computer-aided shape-adapted fabricated titanium mesh for mirroring-reconstructing orbital walls in cases of late post-traumatic enophthalmos.
abstract: OBJECTIVE
  Computer-aided individually shape-adapted fabricated titanium mesh for the mirroring-reconstruction of the orbit is a promising method for the correction of post-traumatic enophthalmos. The purpose of this study was to evaluate the application of this technique and assess the treatment outcomes.
  
  
  METHODS
  Twenty-one patients with delayed treatment of unilateral impure orbital fracture and post-traumatic enophthalmos were included in this study. Computed tomography-based mirroring-reconstruction images of the orbit were obtained for each individual to fabricate anatomically adaptive titanium mesh by computer-aided design and computer-aided manufacturing techniques. After exposing the areas of orbital defect and reducing the herniated soft tissue, the titanium mesh was inserted to reconstruct the internal orbit with a mean deep extension of 29.33 mm. Measurements were performed to assess the change in the degree of enophthalmos and orbital volume before and after surgery. Paired samples t test and Pearson correlation coefficient were employed for statistical analysis.
  
  
  RESULTS
  Follow-up examinations revealed that the degree of enophthalmos decreased to less than 2 mm in 11 patients, 2 to 4 mm in 9 patients, and remained greater than 7 mm in 1 patient. Statistical analysis revealed that post-traumatic enophthalmos in this series was 4.05 +/- 2.02 mm, which was associated with an orbital volume increment of 6.61 +/- 3.63 cm(3), with a regression formula of enophthalmos = 0.446 x orbital volume increment + 2.406. Orbital reconstruction effected a orbital volume decrease of 4.24 +/- 2.41 cm(3) and enophthalmos correction of 2.01 +/- 1.46 mm, the regression formula being enophthalmos = 0.586 x orbital volume decrease + 0.508. After surgery, the degree of unresolved enophthalmos was 2.03 +/- 1.52 mm, and the retained orbital volume expansion was 2.23 +/- 2.86 cm(3), and the regression formula was enophthalmos = 0.494 x orbital volume expansion + 1.415.
  
  
  CONCLUSIONS
  Application of the individual fabricated titanium mesh for orbital reconstruction reduced the trauma-induced orbital volume increment by 65% and corrected 50% of severe late enophthalmos. Additional augmentation of orbital contents was required for further correction. The related treatment parameters were suggested.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Peking University, School and Hospital of Stomatology, Beijing, China. zhangyi2000@263.net
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: He
authors.forename: Zhi Yong
authors.initials: ZY
authors.lastname: Zhang
authors.forename: Jin Gang
authors.initials: JG
authors.lastname: An
mesh_terms: D000328:Adult; D017076:Computer-Aided Design; D015841:Enophthalmos / Q000209:etiology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009917:Orbital Fractures / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000295:instrumentation*; D012044:Regression Analysis; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D013526:Surgical Mesh; D013997:Time Factors; D014025:Titanium; D036542:Tomography, Spiral Computed; D055815:Young Adult
chemical_list: D014025:Titanium