April 2014
Volume 55, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2014
Tract-specific analysis of visual stream structural connectivity in late-blind patients with retinitis pigmentosa
Author Affiliations & Notes
  • Samantha I Cunningham
    Biomedical Engineering, University of Southern California, Los Angeles, CA
  • James D Weiland
    Biomedical Engineering, University of Southern California, Los Angeles, CA
  • Natasha Lepore
    Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA
  • Yaqiong Chai
    Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA
  • Bosco S Tjan
    Neuroscience Graduate Program, University of Southern California, Los Angeles, CA
    Department of Psychology, University of Southern California, Los Angeles, CA
  • Footnotes
    Commercial Relationships Samantha Cunningham, None; James Weiland, None; Natasha Lepore, None; Yaqiong Chai, None; Bosco Tjan, None
  • Footnotes
    Support None
Investigative Ophthalmology & Visual Science April 2014, Vol.55, 5850. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Samantha I Cunningham, James D Weiland, Natasha Lepore, Yaqiong Chai, Bosco S Tjan; Tract-specific analysis of visual stream structural connectivity in late-blind patients with retinitis pigmentosa. Invest. Ophthalmol. Vis. Sci. 2014;55(13):5850. doi: https://doi.org/.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: Neuroimaging studies suggest that vision deprivation in humans leads to functional changes in the visual cortex and visual integration sites, specifically in visual association areas of the parietal lobe and along both ventral and dorsal visual streams. We used tract-specific analyses (Zhang et al., 2010) to determine if vision loss also leads to localized changes in visual stream white matter fiber tracks in late-blind individuals with retinitis pigmentosa (RP), an inherited degenerative photoreceptor disease that progressively diminishes vision.

Methods: Seven RP and 2 sighted subjects underwent a series of DTI and whole-brain resting-state scans. Diffusion tensor images for all subjects were registered to a common atlas that includes medial-representations of 4 white matter tracts: the corpus callosum (CC), inferior fronto-occipital tracts (IFO), inferior longitudinal tracts (ILF), and superior longitudinal tracts (SLF), all of which have connections in the occipital lobe. Tract-specific regression analyses were conducted to identify significant relationships between subjects’ visual function (i.e. visual acuity and fractional preserved visual field) and mean radial diffusivity (RD), apparent diffusion coefficient (ADC), axial diffusivity (AD), and maximum fractional anisotropy (FA) along the 4 tracts. We further defined the functional connectivity along a tract as the correlation (r) between the time courses of 2 ROIs (one at each end of a tract) after regressing out head-motion parameters.

Results: Regression analyses revealed no significant relationship between visual function and mean RD, ADC, AD, or maximum FA values along the 4 white matter tracts examined (FWER corrected, min. p = 0.151). Resting-state results revealed a trending correlation between the functional connectivity of SLF and subjects’ visual field (r = -0.749, FWER p = 0.078).

Conclusions: These results suggest that vision loss in late blind patients does not lead to obvious changes in fiber tract integrity detectable with a small group of subjects. If sustained with data from a larger study, this finding will reaffirm the viability of sight-restoration treatments on individuals with RP, as the underlying anatomical connectivity between the visual system and other parts of the brain is unaffected by lack of visual input.

Keywords: 702 retinitis • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 650 plasticity  
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×