title: [Annular keratopigmentation (PresbyRing®) for treating presbyopia: postmortem animal feasibility study].
abstract: BACKGROUND
  Annular keratopigmentation (PresbyRing(®)) is a new technique which creates an intrastromal ring centered on the visual axis, using a femtosecond laser, into which a black or a colored pigment is then injected. The internal diameter of the ring is dimensioned so as to create a pinhole and improve the near and intermediate vision of the non-dominant eye while only slightly altering the distance vision of that eye.
  
  
  METHODS
  We used five pig eyes for our postmortem feasibility study; all five were treated with the Intra Corneal Ring program (ICR(®)) of the Visumax(®) laser. The dye used (Biochromaderm(®)) has EU approval.
  
  
  RESULTS
  Spectral domain OCT examinations demonstrate complete opacity of the dye. Histological analysis with hematoxylin and eosin stain highlights a continuous pigmented layer located along the incision, which does not diffuse in the adjacent stroma. The possibility of rinsing the dye must be confirmed by future in-vivo animal studies.
  
  
  CONCLUSIONS
  To our knowledge, this study represents the first experimental attempt to combine two ideas which did not appear to have anything in common: the creation of an intracorneal pinhole to treat presbyopia, and corneal tattooing. The first postmortem feasibility study in animals for annular keratopigmentation (PresbyRing(®)) gave encouraging results. It must be confirmed by in vivo animal studies, and ultimately in humans.
authors.affiliation: Expert Vision Center, 6, rue Simonis, 67100 Strasbourg, France. francisferrari@me.com
authors.forename: F
authors.initials: F
authors.lastname: Ferrari
authors.forename: J
authors.initials: J
authors.lastname: Letsch
authors.forename: L
authors.initials: L
authors.lastname: Morin
authors.forename: A
authors.initials: A
authors.lastname: Guignier
authors.forename: L
authors.initials: L
authors.lastname: Marcellin
authors.forename: T
authors.initials: T
authors.lastname: Bourcier
mesh_terms: D000818:Animals; D001344:Autopsy; D004396:Coloring Agents / Q000627:therapeutic use; D003315:Cornea / Q000473:pathology / Q000601:surgery*; D005240:Feasibility Studies; D053685:Laser Therapy / Q000379:methods*; D023421:Models, Animal; D013508:Ophthalmologic Surgical Procedures / Q000379:methods*; D010858:Pigmentation / Q000502:physiology; D011305:Presbyopia / Q000473:pathology / Q000601:surgery*; D013552:Swine
chemical_list: D004396:Coloring Agents