title: What's in a name: keratoconus, pellucid marginal degeneration, and related thinning disorders.
abstract: OBJECTIVE
  To discuss the implications of the current nomenclature and use of current diagnostic modalities on the classification and treatment of pellucid marginal degeneration and keratoconus.
  
  
  METHODS
  Perspective analysis of the literature.
  
  
  METHODS
  Analysis of published reports on the various treatment methods for pellucid marginal degeneration and keratoconus, and the technologies used in these studies to support the diagnosis and classification of these ectatic disorders.
  
  
  RESULTS
  Many studies exploring the different treatment modalities for pellucid marginal degeneration and keratoconus rely mainly on anterior curvature maps to establish the diagnosis of these ectatic disorders, and either do not utilize or disregard information provided by pachymetric maps and posterior elevation maps. In addition, the interchangeability of the nomenclature used to describe these disorders in the literature makes it even more difficult for the clinician to determine the applicability of the results to their patient population.
  
  
  CONCLUSIONS
  We propose that future studies minimally include anterior and posterior elevation maps, anterior curvature topography, and full pachymetric maps. This will allow practitioners a better understanding of the study population, and allow them to ascertain when and in whom the treatment modality being explored may be applicable.
authors.affiliation: University of Arizona Department of Ophthalmology & Vision Science, Tucson, AZ 85658-4741, USA. MWBelin@aol.com
authors.forename: Michael W
authors.initials: MW
authors.lastname: Belin
authors.forename: Ijeoma M
authors.initials: IM
authors.lastname: Asota
authors.forename: Renato
authors.initials: R
authors.lastname: Ambrosio
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Khachikian
mesh_terms: D003315:Cornea / Q000473:pathology*; D003317:Corneal Dystrophies, Hereditary / Q000145:classification / Q000175:diagnosis*; D019781:Corneal Topography; D006801:Humans; D007640:Keratoconus / Q000145:classification / Q000175:diagnosis*; D011446:Prospective Studies; D009626:Terminology as Topic