J Korean Ophthalmol Soc.
2022 Dec;63(12):965-972. 10.3341/jkos.2022.63.12.965.
Phenotypes of Granular Corneal Dystrophy Type 2 among Koreans in Their Twenties
- Affiliations
-
- 1Saevit Eye Hospital, Goyang, Korea
- 2B&VIIt Eye Center, Seoul, Korea
- 3Seyan Eye Center, Seoul, Korea
- 4Department of Ophthalmology and The Institute of Vision Research, Yonsei University College of Medicine, Seoul, Korea
- 5Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul, Korea
- KMID: 2536851
- DOI: http://doi.org/10.3341/jkos.2022.63.12.965
Abstract
- Purpose
Granular corneal dystrophy type 2 (GCD2) is a hereditary disease that features granular and lattice stromal deposits in the cornea. There are homozygotes and heterozygotes and the opacities are exacerbated by corneal trauma or surgery, such as laser in situ keratomileusis (LASIK). As there is individual variability in GCD2 phenotypes, we investigated various corneal features of GCD2 patients in their twenties, the main age group for refractive surgery.
Methods
From genetically confirmed GCD2 patients who had an R124H mutation of the transforming growth factor β induced (TGFBI) gene at age 20 to 29 years, we chose representative patients: one homozygote; one compound heterozygote; one simple heterozygote with a severe phenotype with many granular deposits; one common heterozygote; and four heterozygotes with normal corneas. The corneas of all patients were subject to slit-lamp examination and photographed.
Results
The homozygote had confluent granular deposits covering the cornea. The compound heterozygote had granular and lattice deposits covering the center of the cornea. The patient with a severe phenotype had more than 30 granular deposits in one eye, but was a simple GCD2 heterozygote, verified by full-sequencing of the TGFBI gene. In the four patients with normal corneas, a single small lesion was subsequently detected during follow-up in two, at 3 weeks and 6 months, respectively. Both corneas were judged clear at chance examinations.
Conclusions
Among Koreans in their twenties, GCD2 patients have various phenotypes, from clear corneas to severe confluent opacities. There are GCD2 heterozygotes with nearly clear corneas, so caution must be taken when choosing patients for refractive surgery.
