title: [Risk factors and rejection frequency in patients undergoing penetrating keratoplasty].
abstract: BACKGROUND
  Corneal transplantation is one of the surgical procedures most frequently performed worldwide and with better prognosis. Among its main indications include: keratoconus, bullous keratopathy, previous graft rejection, corneal dystrophy, and infection. The known risk factors for graft rejection are: recipient's age, presence of vessels in the recipient cornea, intraocular pressure, and retransplantation. The objective of this article is to determine the risk factors and frequency of corneal rejection in patients undergoing penetrant keratoplasty.
  
  
  METHODS
  The study's design was descriptive, observational, transversal, analytical and retrospective. Patients operated of penetrating keratoplasty in cornea clinic with follow up during at least 6 months were studied. A review of the medical records of patients undergoing penetrating keratoplasty at the Hospital de Especialidades del Centro Médico Nacional Siglo XXI was performed.
  
  
  RESULTS
  The 35.3 % of the transplanted patients had corneal transplant rejection. Corneal neovascularization of the recipient cornea previous to transplant was present in 21.3 %.
  
  
  CONCLUSIONS
  In our study we found similar results to the reported in the literature, the most important risk factors for rejection was the use of threphine 7.50 mm, older patient with a history with previous corneal neovascularization, keratopathy and herpetic keratitis.
authors.affiliation: División de Oftalmología, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguros Social, Ciudad de México, México. gittinsothon@hotmail.com.
authors.forename: Luis Othón
authors.initials: LO
authors.lastname: Gittins-Nuñez
authors.forename: Ernesto
authors.initials: E
authors.lastname: Díaz Del Castillo-Martín
authors.forename: Irma
authors.initials: I
authors.lastname: Huerta-Albañil
authors.forename: Rita
authors.initials: R
authors.lastname: Ríos-Prado
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Soto-Dávila
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006084:Graft Rejection / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015948:Keratoplasty, Penetrating; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Corneal transplantation; Refractive surgical procedures; Risk factors