title: Pathogenesis and classification of proliferative diabetic vitreoretinopathy.
abstract: OBJECTIVE
  To review the current knowledge regarding the pathogenesis of proliferative diabetic vitreoretinopathy (PDVR) and to present recommendations for its clinical staging.
  
  
  METHODS
  Focused literature review and authors' clinical experience.
  
  
  RESULTS
  Although several biochemical mediators may be responsible for the pathogenesis of PDVR, no common biochemical pathway exists. Of those mediators, vascular endothelial growth factor is the one most studied so far. However, since in proliferative diabetic retinopathy (PDR) the thickened posterior vitreous cortex is one of the main factors in the development of proliferations, a consequent shrinkage of the posterior vitreous cortex leads to hemorrhages and tractive retinal detachments. Therefore, PDR should be called PDVR. In consequence, the authors present a new morphological classification of PDVR.
  
  
  CONCLUSIONS
  There is no consensus about the biochemical pathway responsible for the progression of PDVR. Although several classifications are described in the literature, the classification suggested here is important in the judgment of, the communication about and the therapy of diabetic retinopathy. Furthermore, it is the only reliable classification for predicting the surgical outcome in diabetics.
authors: Department of Ophthalmology, Philipps University Marburg, Marburg, Germany. krollp@med.uni-marburg.de
authors: Peter
authors: P
authors: Kroll
authors: Eduardo Büchele
authors: EB
authors: Rodrigues
authors: Steffen
authors: S
authors: Hoerle
mesh_terms: D003930:Diabetic Retinopathy / Q000145:classification* / Q000175:diagnosis / Q000209:etiology*; D003937:Diagnosis, Differential; D018450:Disease Progression; D006801:Humans; D011379:Prognosis; D012307:Risk Factors; D018630:Vitreoretinopathy, Proliferative / Q000145:classification* / Q000175:diagnosis / Q000209:etiology*