title: Surface-Based Analyses of Anatomical Properties of the Visual Cortex in Macular Degeneration.
abstract: BACKGROUND
  Macular degeneration (MD) can cause a central visual field defect. In a previous study, we found volumetric reductions along the entire visual pathways of MD patients, possibly indicating degeneration of inactive neuronal tissue. This may have important implications. In particular, new therapeutic strategies to restore retinal function rely on intact visual pathways and cortex to reestablish visual function. Here we reanalyze the data of our previous study using surface-based morphometry (SBM) rather than voxel-based morphometry (VBM). This can help determine the robustness of the findings and will lead to a better understanding of the nature of neuroanatomical changes associated with MD.
  
  
  METHODS
  The metrics of interest were acquired by performing SBM analysis on T1-weighted MRI data acquired from 113 subjects: patients with juvenile MD (JMD; n = 34), patients with age-related MD (AMD; n = 24) and healthy age-matched controls (HC; n = 55).
  
  
  RESULTS
  Relative to age-matched controls, JMD patients showed a thinner cortex, a smaller cortical surface area and a lower grey matter volume in V1 and V2, while AMD patients showed thinning of the cortex in V2. Neither patient group showed a significant difference in mean curvature of the visual cortex.
  
  
  CONCLUSIONS
  The thinner cortex, smaller surface area and lower grey matter volume in the visual cortex of JMD patients are consistent with our previous results showing a volumetric reduction in their visual cortex. Finding comparable results using two rather different analysis techniques suggests the presence of marked cortical degeneration in the JMD patients. In the AMD patients, we found a thinner cortex in V2 but not in V1. In contrast to our previous VBM analysis, SBM revealed no volumetric reductions of the visual cortex. This suggests that the cortical changes in AMD patients are relatively subtle, as they apparently can be missed by one of the methods.
authors.affiliation: Laboratory of Experimental Ophthalmology, Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Doety
authors.initials: D
authors.lastname: Prins
authors.affiliation: Institute for Experimental Psychology, University of Regensburg, Regensburg, Germany.
authors.forename: Tina
authors.initials: T
authors.lastname: Plank
authors.affiliation: Department of Psychology, University of York, York, United Kingdom.|Centre for Neuroscience, Hull-York Medical School, York, United Kingdom.
authors.forename: Heidi A
authors.initials: HA
authors.lastname: Baseler
authors.affiliation: Centre for Neuroscience, Hull-York Medical School, York, United Kingdom.
authors.forename: André D
authors.initials: AD
authors.lastname: Gouws
authors.affiliation: Institute for Experimental Psychology, University of Regensburg, Regensburg, Germany.
authors.forename: Anton
authors.initials: A
authors.lastname: Beer
authors.affiliation: Department of Psychology, University of York, York, United Kingdom.|Centre for Neuroscience, Hull-York Medical School, York, United Kingdom.
authors.forename: Antony B
authors.initials: AB
authors.lastname: Morland
authors.affiliation: Institute for Experimental Psychology, University of Regensburg, Regensburg, Germany.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Greenlee
authors.affiliation: Laboratory of Experimental Ophthalmology, Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Frans W
authors.initials: FW
authors.lastname: Cornelissen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008268:Macular Degeneration / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D014785:Vision, Ocular; D014793:Visual Cortex / Q000000981:diagnostic imaging* / Q000503:physiopathology