title: Ultraviolet photography of the in vivo human cornea unmasks the Hudson-Stähli line and physiologic vortex patterns.
abstract: OBJECTIVE
  To perform ultraviolet (UV) macrophotography of the normal in vivo human cornea, establishing biometric data of the major component of UV absorption for comparison with the Hudson-Stähli (HS) line, the distribution of iron demonstrated by Perl stain, and cases of typical amiodarone keratopathy.
  
  
  METHODS
  Nonrandomized comparative case series of UV photographs of 76 normal corneas (group 1) and 16 corneas with typical amiodarone keratopathy (group 2). Image-analysis software was used to grade the major component of UV absorption for slope and the coordinates of its points of intersection with the vertical corneal meridian and inflection.
  
  
  RESULTS
  In group 1 the major component had a mean slope of 5.8 degrees, sloping down from nasal to temporal cornea. The mean coordinates of points of intersection with the vertical corneal meridian and inflection were (0, 0.30) and (0.02, 0.31), respectively. No significant differences between groups 1 and 2 were found for slope (P = 0.155), intersection with the vertical corneal meridian (P = 0.517), and point of inflection (P = 0.344). The major component of UV absorption was consistent with published characteristics of the HS line, and coincidence of UV absorption and Perl-stained iron was demonstrated in one corneal button. A vortex pattern of UV absorption was observed in all corneas.
  
  
  CONCLUSIONS
  UV photography demonstrates subclinical corneal iron, confirming its deposition in an integrated HS line/vortex pattern. Coincident iron and amiodarone deposition occurs in amiodarone keratopathy.
authors.affiliation: Ophthalmology Section, Department of Medical and Surgical Sciences, Dunedin School of Medicine, New Zealand. sean.every@ntlworld.com
authors.forename: Sean G
authors.initials: SG
authors.lastname: Every
authors.forename: John P
authors.initials: JP
authors.lastname: Leader
authors.forename: Anthony C B
authors.initials: AC
authors.lastname: Molteno
authors.forename: Tui H
authors.initials: TH
authors.lastname: Bevin
authors.forename: Gordon
authors.initials: G
authors.lastname: Sanderson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000638:Amiodarone / Q000009:adverse effects; D003315:Cornea / Q000033:anatomy & histology* / Q000502:physiology*; D003316:Corneal Diseases / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology; D005260:Female; D005293:Ferritins / Q000378:metabolism; D006801:Humans; D007501:Iron / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010781:Photography / Q000379:methods*; D014466:Ultraviolet Rays
chemical_list: D005293:Ferritins; D007501:Iron; D000638:Amiodarone