title: Regional cone-mediated dysfunction in age-related maculopathy evaluated by focal electroretinograms: relationship with retinal morphology and perimetric sensitivity.
abstract: OBJECTIVE
  To assess regional cone-mediated function in age-related maculopathy (ARM) by focal electroretinograms (FERGs), and to compare FERGs with morphologic changes and perimetric sensitivity at corresponding locations.
  
  
  METHODS
  Twenty-six ARM patients and 12 age-matched controls were evaluated. FERGs were elicited by either a central (0-2.25 degrees , C) or a paracentral annular (2.25-9 degrees , PC) flickering (41 Hz) field, presented on a light-adapting background. Morphological changes (soft drusen and/or retinal pigment epithelium defects) at matched locations were assessed by fundus photography and fluorescein angiography. Perimetric sensitivity was measured by Octopus 10 degrees program (tM2).
  
  
  RESULTS
  When compared to controls, mean C and PC FERG amplitudes of patients were reduced (p < 0.01), and the mean PC FERG phase was delayed (p < 0.01). Both FERG delays and morphologic lesions tended to involve to a greater extent the PC compared to the C region. In the C region, perimetric losses were correlated with the extent of morphologic lesions (p < 0.05). In the PC region, perimetric losses were correlated with FERG amplitudes (p < 0.05).
  
  
  CONCLUSIONS
  In ARM, FERG losses are eccentricity-dependent, not quantitatively linked to retinal morphology, and correlated with perimetric losses, suggesting a heterogeneous dysfunction with loss of both C and PC perimetric sensitivities.
authors.affiliation: Institute of Ophthalmology, Catholic University, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Piccardi
authors.forename: Lucia
authors.initials: L
authors.lastname: Ziccardi
authors.forename: Giovanna
authors.initials: G
authors.lastname: Stifano
authors.forename: Lucrezia
authors.initials: L
authors.lastname: Montrone
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Iarossi
authors.forename: Angelo
authors.initials: A
authors.lastname: Minnella
authors.forename: Antonello
authors.initials: A
authors.lastname: Fadda
authors.forename: Emilio
authors.initials: E
authors.lastname: Balestrazzi
authors.forename: Benedetto
authors.initials: B
authors.lastname: Falsini
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004596:Electroretinography; D005260:Female; D006801:Humans; D008268:Macular Degeneration / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D017949:Retinal Cone Photoreceptor Cells / Q000473:pathology / Q000502:physiology*; D012680:Sensitivity and Specificity; D058609:Visual Field Tests