title: [Quantitative changes in tear film after refractive surgery: comparative study between PRK and LASIK].
abstract: OBJECTIVE
  To compare quantitative changes induced in the tear film of patients submitted to photorefractive keratectomy and LASIK over a year.
  
  
  METHODS
  A prospective, longitudinal, comparative, post-interventional study was designed to distinguish tear film changes before and one year after refractive surgery procedures in 48 patients submitted to PRK and 36 patients submitted to LASIK, using type 1 Schirmer test in the right eye and red phenol thread test in the left eye.
  
  
  RESULTS
  Tear film assessment between the first and third postoperative month demonstrated Schirmer and phenol red measurements below basal values for both procedures. One year after the procedures, measurements returned to presurgical values.
  
  
  CONCLUSIONS
  Besides momentary and within normal limit changes in the measurement of tear film, no complications were found in normal patients.
authors.affiliation: Setor de Córnea e Doenças Externas, Departamento de Oftalmologia, Santa Casa de Misericórdia de São Paulo, São Paulo, SP, Brazil.
authors.forename: Marcelo Galiano
authors.initials: MG
authors.lastname: Credie
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Nishiwaki-Dantas
authors.forename: Sérgio
authors.initials: S
authors.lastname: Felberg
authors.forename: Fabiana
authors.initials: F
authors.lastname: Amorim
authors.forename: Paulo Elias Correa
authors.initials: PE
authors.lastname: Dantas
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D007765:Lacrimal Apparatus / Q000378:metabolism*; D054018:Lasers, Excimer; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D018903:Photorefractive Keratectomy; D011184:Postoperative Period; D011446:Prospective Studies; D013666:Tears / Q000378:metabolism*