Abstract
Purpose :
To investigate in vivo corneal changes of Bowman’s layer dystrophy using anterior segment optical coherence tomography (AS-OCT).
Methods :
Five patients from 2 pedigrees (1 male, 4 females) with Reis-Bücklers corneal dystrophy (RBCD)(Arg124Leu (R124L) heterozygous missense mutation of human transforming growth factor beta-induced (TGFBI) gene) and 4 patients from 3 pedigrees (3 males, 1 female) with Thiel-Behnke corneal dystrophy (TBCD) (Arg555Gln (R555Q) heterozygous missense mutation of TGFBI gene) were examined. Three patients of Reis-Bücklers corneal dystrophy exhibited recurrence after corneal transplantation and/or phototherapeutic keratectomy. All patients were examined by slit-lamp biomicroscopy followed by AS-OCT (RTVue-100® Optovue Inc, Fremont, California, U.S.A.). Selected AS-OCT images of the cornea were evaluated qualitatively for changes in the shape and degree of light reflection.
Results :
Slit-lamp biomicroscopy showed characteristic irregular grayish opacities at the level of Bowman’s layer in each dystrophy: geographic pattern in RBCD and honeycomb pattern in TBCD. In each dystrophy, distinct characteristic deposits were observed as a banding lesion at the level of Bowman’s layer and its adjacent epithelium/stroma by AS-OCT. In RBCD, the banding lesion was sharply marginated with extremely high reflectivity. In contrast, deposits in TBCD in the same cell layer showed saw-tooth pattern toward epithelium and poorly marginated in stroma. The lesion in TBCD showed much less reflectivity compared to those in RBCD. In both dystrophies, no abnormal deposits were seen in stromal layer, Descemet’s membrane and endothelial layer in any of the nine patients.
Conclusions :
AS-OCT is capable of identifying characteristic in vivo corneal microstructural changes related to RBCD and CBCD. As a result, this device may enable differentiation of RBCD and CBCD in vivo. AS-OCT may also be a valuable tool for further research into the corneal dystrophies especially to follow the natural course.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.