title: Proposal of a novel classification of leukocorias.
abstract: BACKGROUND
  To report a case series of nine patients presenting with leukocoria without lens opacification or retrolental abnormalities and to propose a novel classification for leukocoria.
  
  
  METHODS
  An institutional and retrospective study including a case series of patients assisted in the Congenital Cataract Section of Federal University of São Paulo, Brazil, during the period between 2005 and 2010 with prelenticular leukocoria and clear lens.
  
  
  RESULTS
  Nine patients younger than 4 years old presented with the diagnosis of unilateral prelenticular opacities without cataract formation. Echography in all patients revealed no posterior segment or lens abnormalities in the affected eye. Among the patients, three had idiopathic prelenticular membrane, two presented with juvenile xanthogranuloma with secondary pupillary membrane, one had persistent fetal pupillary membrane, one had prelenticular membrane due to congenital toxoplasmosis, one presented with pupillary membrane due to hyphema caused by iris hemangioma, and one had anterior segment persistent fetal vasculature.
  
  
  CONCLUSIONS
  This case series of patients presented unilateral prelenticular leukocoria without lens opacification or posterior segment abnormalities. Several etiologies were associated with this condition. The correct diagnosis is important in order to avoid clear lens extraction. A new classification of leukocoria is proposed herein including: prelenticular leukocoria, lenticular leukocoria, retrolenticular leukocoria, and mixed presentation leukocoria.
authors: Department of Ophthalmology, Congenital Cataract Section, Federal University of São Paulo, São Paulo SP, Brazil.
authors: Marcia Beatriz
authors: MB
authors: Tartarella
authors: Glória Fátima
authors: GF
authors: Britez-Colombi
authors: João Borges
authors: JB
authors: Fortes Filho