title: PERSISTENT CORNEAL EPITHELIAL DEFECT AFTER PARS PLANA VITRECTOMY.
abstract: OBJECTIVE
  To investigate the incidence, risk factors, and clinical course of persistent corneal epithelial defects (PCED) after pars plana vitrectomy (PPV).
  
  
  METHODS
  The charts of 426 consecutive patients (511 eyes) who received PPV from January 2008 to December 2011 were reviewed. Corneal complications were defined as the presence of corneal epithelial defects, corneal edema, or superficial punctate keratopathy at least 1 week after vitrectomy. The PCED was defined as corneal epithelial defects lasting longer than 2 weeks after vitrectomy despite conventional treatment. The demographic, preoperative, intraoperative, and postoperative data were compared between PCED and non-PCED corneal complication groups to evaluate the risk factors and clinical outcomes.
  
  
  RESULTS
  Postoperative corneal complications developed in 103 of 460 (22.4%) eyes. Diabetes was associated with postoperative corneal epithelial defects (P = 0.021) and superficial punctate keratopathy (P = 0.022) but not corneal edema (P = 0.925). Among 103 eyes with corneal complications, 21 eyes developed PCED. The eyes with PCED had poor final visual acuity, with 23.8% (5/21) of the eyes in the PCED group having visual acuity of 20/200 or better compared with 51.2% (42/82) of the eyes in the non-PCED group (P = 0.024). Logistic regression analysis demonstrated that diabetes mellitus (P = 0.025), use of perfluoropropane (P = 0.001), and assistance of a first-year resident (P = 0.029) were statistically significant risk factors for PCED after PPV. There was also a high incidence of geographic herpes simplex virus epithelial keratitis among recalcitrant PCEDs lasting longer than 4 weeks (36%, 4/11 eyes).
  
  
  CONCLUSIONS
  The overall incidence of PCED after PPV was 4.8%. Diabetes mellitus, intravitreal tamponade with perfluoropropane, and assistance of a first-year resident were risk factors for PCED after PPV. Persistent corneal epithelial defects after PPV were correlated with poor postoperative visual outcomes. Early and aggressive management is necessary for patients presenting with corneal epithelial defects after vitrectomy to prevent poor outcomes.
authors.affiliation: *Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan; †University Eye Center, Taipei, Taiwan; and ‡Department of Chinese Medicine, Chang Gung University, Kwei-shan, Taoyuan, Taiwan.
authors.forename: Hsi-Fu
authors.initials: HF
authors.lastname: Chen
authors.forename: Ling
authors.initials: L
authors.lastname: Yeung
authors.forename: Ko-Jen
authors.initials: KJ
authors.lastname: Yang
authors.forename: Chi-Chin
authors.initials: CC
authors.lastname: Sun
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003316:Corneal Diseases / Q000209:etiology*; D058450:Endotamponade; D019573:Epithelium, Corneal / Q000473:pathology*; D005260:Female; D005466:Fluorocarbons / Q000008:administration & dosage; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012163:Retinal Detachment / Q000601:surgery; D012189:Retrospective Studies; D012307:Risk Factors; D012591:Scleral Buckling; D012827:Silicone Oils / Q000008:administration & dosage; D013459:Sulfur Hexafluoride / Q000008:administration & dosage; D014821:Vitrectomy / Q000009:adverse effects*
chemical_list: D005466:Fluorocarbons; D012827:Silicone Oils; C042852:perflutren; D013459:Sulfur Hexafluoride