title: Magnification changes in specular microscopy after corneal refractive surgery.
abstract: OBJECTIVE
  To describe the effect of corneal refractive surgery on the magnification of a contact and a non-contact specular microscope.
  
  
  METHODS
  The magnification of a contact specular microscope (Konan Clinical Specular Microscope) and a non-contact specular microscope (Topcon SP-1000) was experimentally and theoretically studied as a function of anterior corneal refractive power and central corneal thickness.
  
  
  RESULTS
  The magnification of the contact and non-contact specular microscope was found to decrease slightly with decreasing central corneal thickness. In addition, the magnification of the non-contact specular microscope decreased slightly with decreasing anterior corneal refractive power.
  
  
  CONCLUSIONS
  As the preoperative and postoperative measuring conditions are different in patients undergoing corneal refractive surgery a correction for magnification changes is necessary when small changes in endothelial cell density are looked for.
authors.affiliation: Department of Ophthalmology, Arhus University Hospital, Denmark.
authors.forename: P
authors.initials: P
authors.lastname: Isager
authors.forename: J O
authors.initials: JO
authors.lastname: Hjortdal
authors.forename: N
authors.initials: N
authors.lastname: Ehlers
mesh_terms: D002452:Cell Count; D003315:Cornea / Q000502:physiology*; D004728:Endothelium, Corneal / Q000166:cytology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007646:Keratotomy, Radial; D054018:Lasers, Excimer; D008853:Microscopy / Q000379:methods*; D010784:Photomicrography; D018903:Photorefractive Keratectomy; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D012029:Refraction, Ocular; D012030:Refractive Errors / Q000503:physiopathology; D054140:Refractive Surgical Procedures