Abstract
Purpose:
Our purpose was to measure the pulsatile deformation of the neuroretinal rim and the peripapillary neuroretina in normal subjects using a commercial SD-OCT platform. This deformation is presumably driven by the pulsatile filling of the choroid during the cardiac cycle and we have hypothesized that it could play a role in the pathogenesis of glaucoma.
Methods:
Normal subjects were recruited for imaging sessions in one eye. The Spectralis SD-OCT was modified to create a time series of a single line across the optic nerve head at 19.5 Hz at 45 degrees axis and at 135 degrees. Automated image segmentation and image analysis algorithms were developed to delineate the surface of the peripapillary retina, rim, and base of the cup and its change over time. The root mean squared deformation of this surface was calculated from these curves.
Results:
Data was analysed from 19 subjects. All subjects had normal optic nerves and no concomitant ocular disease save possible early cataracts. The average age was 71.3 +/- 11.2 yrs. The mean +/- SD RMS deformation was 19.0 +/- 10.0 um inferotemporally and 16.5 +/- 10.4 um superotemporally, values which did not differ significantly from each other (p=N.S.).
Conclusions:
There is evidence of pulsatile deformation of the peripapillary retina and neuroretinal rim. This deformation can be measured using a commercial SD-OCT platform modified to scan a smaller surface at a faster rate. Further studies will be required to determine the role of this deformation in the pathogenesis of glaucoma.
Keywords: 627 optic disc •
550 imaging/image analysis: clinical •
577 lamina cribrosa