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Updated: May 30, 2026
Anterior High-Resolution Optical Coherence Tomography in the Diagnosis and Therapeutic Monitoring of Ocular Surface Squamous Neoplasia
Published on: August 9, 2024
Non-invasive anterior segment and posterior segment optical coherence tomography and phenotypic characterization of
Kevin Gregory-Evans1, Richard Cheong-Leen, Sheena M George
1Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, Canada.
Objective:
To determine the value of optical coherence tomography (OCT) as a diagnostic tool in the critical evaluation of phenotypic variability seen in an aniridia family with a novel PAX6 mutation.
Design:
Genetic and observational family study.
Participants:
Three-generation family segregating autosomal dominant aniridia.
Methods:
Ophthalmic examination included best-corrected visual acuity, slit-lamp biomicroscopy, direct and indirect ophthalmoscopy, tonometry, and OCT. PAX6 gene mutation analysis was carried out by direct sequencing of gene-specific PCR products and protein analysis by Western blot.
Results:
Intrafamilial variable expressivity was seen between 4 affected family members. Phenotype differences between twin children suggested that this was due to modifier gene effects rather than environment. Anterior segment OCT demonstrated a range of iridocorneal angle abnormalities and corneal thickening in only 3, but ciliary body hypoplasia in all 4 affected patients. Posterior segment OCT demonstrated dome-shaped, hypoplastic macular profiles in the 2 affected children. Novel outer retinal changes were also seen, suggestive of a phototoxic retinopathy not previously recognized in aniridia. Ocular disease segregated with a novel PAX6 Q178X nonsense mutation with Western blot analysis suggesting that this led to haploinsufficiency of PAX6 protein.
Conclusions:
Non-contact OCT imaging allowed for a more detailed assessment of anterior and posterior segment disease in children and adults with aniridia plus nystagmus. This led to the identification of novel features and highlights a practical, non-contact strategy well suited to genotype/phenotype studies and the longitudinal management of aniridic glaucoma in children.
