title: Reduced mesopic and photopic foveal contrast sensitivity in glaucoma.
abstract: OBJECTIVE
  To demonstrate differences in foveal contrast sensitivity (CS) between glaucomatous and nonglaucomatous eyes using a simple, rapid computerized test.
  
  
  METHODS
  This study included consecutive patients with glaucoma (35 eyes) and age-matched control participants (23 eyes) with visual acuity of 20/30 or better. Patients with any other ocular disease, including cataract, were excluded. All participants underwent a comprehensive ocular examination, perimetry, and CS. Contrast sensitivity was examined by means of 2 computerized psychophysical tests. The transient method included the presentation of a target in a temporal, 2-alternative, forced-choice procedure, and the static method involved 4 forced-choice procedures. The targets were Gabor patches with spatial frequencies of 1.5 to 9.0 cycles per degree. The tests were conducted under photopic and mesopic conditions.
  
  
  RESULTS
  Significantly lower foveal CS was found in glaucomatous eyes under photopic and mesopic conditions for all spatial frequencies (P < .01). The transient and static methods yielded similar results and were significantly correlated (P < .001). All transient photopic and mesopic CSs were significantly correlated with cup to disc ratio (P < .05). The static photopic spatial frequency of 6 cycles per degree was significantly correlated with the severity of the glaucomatous damage.
  
  
  CONCLUSIONS
  The results indicate that foveal CS is impaired in glaucoma despite good visual acuity, suggesting that central visual function damage occurs in glaucoma. The similarity between the 2 methods of testing implies that the static method, being the shorter and easier one, may be used in future research. Further research is necessary to establish a CS testing role in the screening and monitoring of glaucoma.
authors.affiliation: Goldschleger Eye Research Institute, Tel-Aviv University, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Karen
authors.initials: K
authors.lastname: Lahav
authors.forename: Hani
authors.initials: H
authors.lastname: Levkovitch-Verbin
authors.forename: Michael
authors.initials: M
authors.lastname: Belkin
authors.forename: Yoseph
authors.initials: Y
authors.lastname: Glovinsky
authors.forename: Uri
authors.initials: U
authors.lastname: Polat
mesh_terms: D055253:Color Vision / Q000502:physiology*; D015350:Contrast Sensitivity / Q000502:physiology*; D005260:Female; D005584:Fovea Centralis / Q000502:physiology*; D005901:Glaucoma / Q000503:physiopathology*; D006801:Humans; D008297:Male; D055255:Mesopic Vision / Q000502:physiology*; D008875:Middle Aged; D014787:Vision Tests; D014792:Visual Acuity / Q000502:physiology