Readme: Descriptive data for USN Research Data Archive

Dataset generated by Hilde R. Pedersen and Rigmor C. Baraas


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GENERAL INFORMATION
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TITLE FOR THE DATASET

The cone photoreceptor mosaic in aniridia: within-family phenotype-genotype
discordance

AOSLO_ConeMosaic_Aniridia: 
Measurements of the cone photoreceptor mosaic and density for five persons
with PAX6 related congenital aniridia.

AOSLO_ConeMosaic_Aniridia_RepeatedMeasures: 
Inter- and intra observer repeated cone counting for the five persons with
aniridia.



CONTACT INFORMATION

Professor Rigmor C. Baraas
University of South-Eastern Norway
Hasbergsvei 36
3616 Kongsberg
Norway
rigmor.baraas@usn.no


DATA COLLECTION
2016–2018 in Norway


LANGUAGE
English 


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FILE INFORMATION
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The files are comma-separated text files and can be imported into R
statistical software, Excel or other spreadsheet programs.


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METHODOLOGY
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Adaptive optics scanning light ophthalmology (AOSLO) was used to obtain images
of the photoreceptor mosaic within one degree of the foveal location, and
along the temporal and nasal meridians out to 5 degrees eccentricity sampled
at 0.5deg or 1deg-intervals. Individual cones in the confocal images were
identified via a semi-automatic algorithm, as described previously by Li &
Roorda, J Opt Soc Am A Opt Image Sci Vis. 2007;24:1358-1363, implemented in
custom software.

pid: Participant ID
xpos: Retinal eccentricities from the foveal center given in degrees. Negative
numbers represent the nasal meridian and positive numbers the temporal
meridian.
xpos_r: Retinal eccentricities rounded to nearest 0.1 degree. 
ypos: Retinal eccentricities in degrees along the vertical meridian. 
conedensity: Cone density was estimated over 50x50µm sampling windows and is
given in cones per square millimeter.
NND: Nearest neighbour distance, the average distance between each cone and
its nearest neighbour for all cones whose Voronoi cell was completely
contained within the sampling window.
ICD_mean: Inter-cell distance, the average distance between a cone and all of
its neighbours.
percent_N6: The percentage of 6-sided Voronoi cells.
ICD_CV: Inter-cell distance coefficient of variation, CV = standard deviation/mean. 
conedensity_r1: Cone counting repeated by the same operator (author HRP).
conedensity_r2: Cone counting repeated by a second operator (author RCB).

These data are for each participant’s dominant eye.