title: Ectatic disorders associated with a claw-shaped pattern on corneal topography.
abstract: OBJECTIVE
  To identify clinical findings associated with claw-shaped patterns on corneal topography.
  
  
  METHODS
  Retrospective, observational case series.
  
  
  METHODS
  Forty eyes (26 patients) with classic claw-shaped patterns on corneal topography were identified from 3,993 Orbscan II records. They were subclassified into three groups: Group 1 (pellucid marginal degeneration [PMD] or PMD suspect); group 2 (keratoconus or keratoconus suspect); and group 3 (ectasia). The refractive and topographic indices of groups 1 and 2 were compared.
  
  
  RESULTS
  There were nine eyes (six patients) in group 1, 27 eyes (18 patients) in group 2, and four eyes (two patients) in group 3. The mean radii of maximal anterior (2.96 mm) and posterior (3.06 mm) elevation in group 1 were significantly greater than those of group 2 (1.89 mm; P = .018 and 1.72 mm; P = .022, respectively).
  
  
  CONCLUSIONS
  The claw-shaped pattern on corneal topography is not diagnostic of PMD; it is also seen in keratoconus.
authors.affiliation: Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Brandon W
authors.initials: BW
authors.lastname: Lee
authors.forename: Ula V
authors.initials: UV
authors.lastname: Jurkunas
authors.forename: Mona
authors.initials: M
authors.lastname: Harissi-Dagher
authors.forename: Antony M
authors.initials: AM
authors.lastname: Poothullil
authors.forename: Faisal M
authors.initials: FM
authors.lastname: Tobaigy
authors.forename: Dimitri T
authors.initials: DT
authors.lastname: Azar
mesh_terms: D003315:Cornea / Q000473:pathology*; D003317:Corneal Dystrophies, Hereditary / Q000175:diagnosis*; D019781:Corneal Topography; D004108:Dilatation, Pathologic / Q000175:diagnosis; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis*; D012189:Retrospective Studies