title: Posterior vitreous detachment induced by microplasmin.
abstract: OBJECTIVE
  To demonstrate the efficacy of microplasmin in inducing posterior vitreous detachment (PVD) and to evaluate the human and the feline retina after treatment.
  
  
  METHODS
  Thirteen human donor eyes were injected with 62.5, 125, or 188 micro g microplasmin. The 13 fellow eyes received balanced salt solution. Four of the microplasmin-treated eyes received an additional intravitreal gas injection. After incubation at 37 degrees C for 30 minutes, all globes were placed in 4% paraformaldehyde. Retinal specimens were processed for scanning (SEM) and transmission (TEM) electron microscopy. Five feline eyes were injected with 14.5- or 25- micro g microplasmin. Animals were killed after 1 day, 3 days, or 3 weeks, and retinal specimens were evaluated by electron and confocal microscopy.
  
  
  RESULTS
  In all control eyes, SEM demonstrated the cortical vitreous covering the inner limiting membrane (ILM). Intravitreal injection of 125 or 188 micro g microplasmin resulted in complete PVD. After treatment with 62.5 micro g microplasmin, SEM revealed collagen fibrils covering the ILM. Additional gas injection did not change the dose necessary for PVD. In vivo in cats, 25 micro g microplasmin resulted in complete PVD after 3 days. After 3 weeks, there was complete PVD with both doses of microplasmin. The retina and the ILM were well preserved in all eyes.
  
  
  CONCLUSIONS
  Both after death and in vivo, microplasmin induces a dose-dependent cleavage between the vitreous cortex and the ILM without morphologic alterations of the retina. In the feline eye, there is no cellular response of retinal glial cells or neurons.
authors.affiliation: Department of Ophthalmology, University Eye Hospital, Ludwig-Maximilians-University, Munich, Germany. arnd.gandorfer@ak-i.med.uni-muenchen.de
authors.forename: Arnd
authors.initials: A
authors.lastname: Gandorfer
authors.forename: Matthias
authors.initials: M
authors.lastname: Rohleder
authors.forename: Charanjit
authors.initials: C
authors.lastname: Sethi
authors.forename: Dominik
authors.initials: D
authors.lastname: Eckle
authors.forename: Ulrich
authors.initials: U
authors.lastname: Welge-Lüssen
authors.forename: Anselm
authors.initials: A
authors.lastname: Kampik
authors.forename: Philip
authors.initials: P
authors.lastname: Luthert
authors.forename: David
authors.initials: D
authors.lastname: Charteris
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D002415:Cats; D004305:Dose-Response Relationship, Drug; D005341:Fibrinolysin / Q000008:administration & dosage*; D005343:Fibrinolytic Agents / Q000008:administration & dosage*; D006801:Humans; D007267:Injections; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D009457:Neuroglia / Q000187:drug effects / Q000648:ultrastructure; D010446:Peptide Fragments / Q000008:administration & dosage*; D012160:Retina / Q000187:drug effects / Q000648:ultrastructure; D013997:Time Factors; D014822:Vitreous Body / Q000187:drug effects* / Q000648:ultrastructure; D020255:Vitreous Detachment / Q000139:chemically induced* / Q000473:pathology
chemical_list: D005343:Fibrinolytic Agents; D010446:Peptide Fragments; C054561:microplasmin; D005341:Fibrinolysin