Prevalence and type of artefact with spectral domain optical coherence tomography macular ganglion cell imaging in glaucoma surveillance

PURPOSE:The ganglion cell analysis (GCA) of the CIRRUSTM HD-OCT (Carl Zeiss, Meditec; Dublin, CA) provides measurement of the macular ganglion cell-inner plexiform layer (GCIPL) thickness. This study determined the frequency of scan artefacts and errors in GCIPL imaging in individuals undergoing HD-OCT surveillance for glaucoma. METHOD:A total of 1439 eyes from 721 subjects enrolled in a prospective study assessing predictors of glaucoma progression underwent macular GCIPL imaging with the CIRRUS HD-OCT at recruitment. The prevalence of acquisition errors, segmentation errors, and co-morbid macular pathology was determined. RESULTS:A total of 87 (6.0%) of the 1439 scans had either acquisition errors, segmentation artefacts, or other macular pathology. The most common co-morbid macular pathology was epiretinal membrane in 2.2% of eyes. CONCLUSION:The macular GCIPL scan was artefact free in 94% of eyes. However, epiretinal membrane and high myopia can cause scan artefact and should be considered when interpreting the results.Mona S. Awadalla, Jude Fitzgerald, Nicholas H. Andrew, Tiger Zhou, Henry Marshall, Ayub Qassim, Mark Hassall, Robert J. Casson, Stuart L. Graham, Paul R. Healey, Ashish Agar, Anna Galanopoulos, Simon Phipps, Angela Chappell, John Landers, Jamie E. Crai

Demographics of keratoconus cases and controls at the time of examination, where n = the number of individuals and age is reported in years.

<p>Demographics of keratoconus cases and controls at the time of examination, where n = the number of individuals and age is reported in years.</p

Burden test results for genes in which at least one potentially pathogenic variant was identified in the case cohort.

<p>For each gene, the number of alternate (alt.) alleles (potentially pathogenic variants) and wild type alleles (WT) are shown for both cases and controls, along with the p-value (P), odds ratio (OR) and the 95% confidence interval (CI).</p

Major sub-networks/modules enriched in the high-tension glaucoma cohort.

<p>A: module 1 genes were significantly enriched for the <i>EGFR1</i> pathway. B: module 2 genes were significantly enriched for the Class I MHC mediated antigen processing & presentation pathway. C: module 3 genes were significantly enriched for the cell cycle pathway.</p

Flowchart showing network analysis using InnateDB using High-Tension Glaucoma (HTG) enriched genes as an example.

<p>Flowchart showing network analysis using InnateDB using High-Tension Glaucoma (HTG) enriched genes as an example.</p

Clinical detail of POAG participants.

<p>The Mann-Whitney U test was used to assess statistical significance. HTG = high-tension glaucoma, NTG = normal-tension glaucoma, IOP = intraocular pressure, MD = mean deviation, CDR = cup-to-disc ratio, CCT = central corneal thickness.</p

Venn diagram showing number of genes enriched in high-tension glaucoma, normal-tension glaucoma and all primary open-angle glaucoma cohorts compared with each of the control cohorts (local, AOGC and ExAC).

<p>Venn diagram showing number of genes enriched in high-tension glaucoma, normal-tension glaucoma and all primary open-angle glaucoma cohorts compared with each of the control cohorts (local, AOGC and ExAC).</p

Mean number of variants remaining at each stage of post-sequencing filtering.

<p>Mean number of variants remaining at each stage of post-sequencing filtering.</p

Major sub-networks/modules enriched in normal-tension glaucoma cohort.

<p>A: module 1 genes were not significantly enriched for any known biological pathways. B: module 2 genes were significantly enriched for the <i>EGFR1</i> and cell cycle pathways.</p

Significantly enriched Gene Ontology and biological pathways in POAG and its sub-types.

<p>LoF = Loss of function, OR = Odds ratio, CI = confidence interval.</p