Abstract
Purpose: :
To analyze and compare corneal morphologic features among age-matched patients with the same TGFβI mutation from one and from different families diagnosed with TGFβI corneal dystrophies
Methods: :
The study was approved by polish bioethics committee. 72 members from 17 families were included. The diagnosis of corneal dystrophy type was confirmed by polymerase chain reaction and sequencing of all coding exons of TGFβI gene. We analyzed the age of the disease onset and the presence of recurrent erosion syndrome. The morphologic analysis was based on slit lamp biomicroscopy with photography and anterior segment time domain and spectral domain optical coherence tomography. We analyzed corneal changes pattern, location, symmetry and progression with age.Because corneal changes in all TGFβI dystrophies progressed with age, we selected a group of 34 age-matched members of 9 families and compared corneal morphologic features among them.
Results: :
We diagnosed 3 families with Thiel-Behnke corneal dystrophy (heterozygous R555Q mutation), 5 families with granular corneal dystrophy (heterozygous R555W mutation), 7 families with lattice corneal dystrophy I (heterozygous R124C mutation) and 2 families with lattice corneal dystrophy I/III (heterozygous H626R mutation). We observed no intra or interfamilial phenotypic heterogeneity in TBCD or GCD1. In case of 1 family with R124C and 2 families with H626R mutation we observed significant differences in morphologic features.The first H626R family had asymmetric, late-onset dystrophy with thin fragile lines extending to DM on OCT scan, while the other family had both eyes involved with thick, distinct lines accompanied with stromal haze, also extended to DM.4 age-matched members of one R124C family had different corneal changes pattern as analyzed during biomicroscopy and OCT.Despite of one identified R124C mutation we observed changes in the disease onset and the presence of recurrent erosion syndrome.
Conclusions: :
Classification and diagnosis of TGFβI corneal dystrophies based on only phenotype or genotype analysis can be misleading because of intra and interfamilial heterogeneity. Further studies should be undertaken to explain whether this phenotypic heterogeneity is the result of environmental influence of other unknown genetic features.
Keywords: cornea: stroma and keratocytes • imaging/image analysis: clinical • genetics