title: Comparative study of modified and conventional secondary hydroxyapatite orbital implantations.
abstract: OBJECTIVE
  To compare the clinical effects of the modified and conventional secondary hydroxyapatite orbital implantations.
  
  
  METHODS
  A total of 40 patients who had received eye enucleation were equally randomized into the modified and conventional groups. Twenty patients were treated by conventional method. The four rectus muscles were separated, and then an orbital implant wrapped with xenogenous sclera was implanted. Twenty patients were treated by modified method. An implant unwrapped with xenogenous sclera was directly implanted into the muscle pyramid. The operating time, costs, clinical effects, and complications of the two groups were compared.
  
  
  RESULTS
  The average operating time of the modified group was 20.5±5.6min, whereas that of the conventional group was 56.8±14.6min (P<0.01). The average cost of the modified group was 7 800±340RMB (1 274±55.6USD), whereas that of the conventional group was 9 800±660RMB (1 601±107.8USD) (P<0.01). The two groups did not show significant difference in orbital implant mobility or postoperative complications.
  
  
  CONCLUSIONS
  The modified secondary hydroxyapatite orbital implantation has advantages in operating time, surgery cost, and complication reducing. It is worthy for wide clinical application and further study.
authors.affiliation: Department of Ophthalmology, Chinese PLA General Hospital, Beijing 100853, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhao
authors.forename: Mao-Nian
authors.initials: MN
authors.lastname: Zhang
authors.forename: Yun-Xian
authors.initials: YX
authors.lastname: Gao
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Gao
authors.forename: Bing
authors.initials: B
authors.lastname: Ren
keywords: hydroxyapatite; orbit; orbital implantation