Correspondence
Late-onset lattice corneal dystrophy associated TGFBI p.H626R mutation in members of a Canadian family
Within the over 70 reported transforming growth factor-beta–induced (TGFBI) corneal dystrophy mutations,1 more than 40 are associated with lattice corneal dystrophy (LCD), subtypes I, III, IIIA, and IIIB according to the Human Gene Mutation Database (QIAGEN, Hilden, Germany). This is a follow-up investigation to a study we published in 2018 in the Canadian Journal of Ophthalmology entitled Trauma-induced exacerbation of epithelial-stromal TGFBI lattice corneal dystrophy. This study reported 2 cases of post-laser-assisted in situ keratomileusis (LASIK) and postcorneal injury exacerbated late-onset LCD, attributed to a p.H626R mutation in the TGFBI protein.Inadvertent corneal stromal staining by trypan blue following Descemet's membrane endothelial keratoplasty
Trypan blue is an azo dye solution that effectively stains basement membranes such as the anterior lens capsule and Descemet's membrane.1 In Descemet's membrane endothelial keratoplasty (DMEK), where the host Descemet's membrane and corneal endothelium are initially removed, trypan blue is used to stain the donor graft before injection to provide visibility during the unscrolling process in the anterior chamber. Trypan blue can also be injected after the descemetorrhexis and before graft injection to visualize any irregular tags or retained Descemet's membrane, both of which may increase the risk for graft detachment.Trauma-induced exacerbation of epithelial-stromal TGFBI lattice corneal dystrophy
Several heritable diseases of the cornea known as corneal dystrophies are caused by mutations within the human genome. With the advent of genetic sequencing, it is possible to link most corneal dystrophies to a specific gene mutation.1 While Transforming Growth Factor Beta I (TGFBI) is the most studied gene, with over 60 documented single point mutations,2 without sequencing the patient’s DNA it is difficult to determine if mutations within TGFBI are causal when a patient has symptoms of the disease.
