title: Evaluation of the safety of sclerotomy incision in patients with choroidal colobomas with/without associated microcornea.
abstract: OBJECTIVE
  Whether the position of the ora serrata is normal in patients with choroidal colobomas remains unknown. The aim of this study was to measure the distance between the ora serrata and limbus in these patients and define safe sclerotomy sites for standard three-port pars plana vitrectomy.
  
  
  METHODS
  Twelve patients with choroidal colobomas with normal corneas (Group 1) and 11 patients with choroidal colobomas with microcornea (Group 2) were included in the study. Twelve patients with simple retinal detachment served as control subjects. All participants underwent vitrectomy. The distance between the limbus and ora serrata, corneal diameter, and ocular axial length were measured.
  
  
  RESULTS
  The average corneal diameter was 10.9 mm in Group 1, 7.9 mm in Group 2, and 11.4 mm in the control group. The average distance between the limbus and ora serrata was 6.3 mm in Group 1, 7.6 mm in Group 2, and 6.2 mm in the control group. There were significant differences in the distance between the limbus and ora serrata among the 3 groups (analysis of variance test, P < 0.05).
  
  
  CONCLUSIONS
  Our study confirmed that it is safe to perform a sclerotic puncture 4 mm posterior to the limbus for vitrectomy in patients with choroidal colobomas with or without microcornea.
authors.affiliation: *Department of Ophthalmology, Chinese PLA General Hospital, Beijing, China; †Department of Ophthalmology, Hainan Branch of Chinese PLA General Hospital, Sanya, China; ‡Department of Ophthalmology, Beijing Shijitan Hospital, Capital Medical University, Beijing, China; §Department of Gastroenterology and Hepatology, Hainan Branch of Chinese PLA General Hospital, Beijing, China; ¶Department of Ophthalmology and Shiley Eye Center, University and California, San Diego, La Jolla, California; and **Department of Ophthalmology, Affiliated Hospital of Weifang Medical University, Weifang, China.
authors.forename: Tiecheng
authors.initials: T
authors.lastname: Liu
authors.forename: Maonian
authors.initials: M
authors.lastname: Zhang
authors.forename: Bing
authors.initials: B
authors.lastname: Xu
authors.forename: Weifeng
authors.initials: W
authors.lastname: Wang
authors.forename: Janet
authors.initials: J
authors.lastname: Lee
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Gao
authors.forename: Xuemin
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D058452:Axial Length, Eye / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D002829:Choroid / Q000002:abnormalities*; D003103:Coloboma / Q000473:pathology*; D003315:Cornea / Q000002:abnormalities*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012163:Retinal Detachment / Q000209:etiology / Q000601:surgery*; D012590:Sclera / Q000601:surgery; D012599:Sclerostomy / Q000009:adverse effects / Q000592:standards*; D014821:Vitrectomy / Q000379:methods; D055815:Young Adult