Post-LASIK and post-corneal injury exacerbation of late-onset lattice corneal dystrophy associated with H626R TGFBI mutation in a Canadian family

Session Details

Session Title: SMILE vs PRK, Ocular Surface Disease

Session Date/Time: Monday 24/09/2018 | 08:00-10:30

Paper Time: 09:02

Venue: Room A3, Podium 3

First Author: : C.Chao-Shern UK

Co Author(s): :    L. DeDionisio   J. Jang   C. Chan   M. Nesbit   C. Moore        

Abstract Details

Purpose:

Since its first description in 1999, the occurrence of late-onset Lattice Corneal Dystrophy (late-onset LCD) associated with the TGFBI mutation p.H626R (CAT>CGT) has been reported in Mexico, UK, Singapore, China, France and the USA,. Here, we report post-LASIK and post-corneal injury exacerbation of late-onset LCD within a Canadian family of Italian descent found to carry the H626R TGFBI mutation. Pre-operative genetic screening for this mutation should be considered for asymptomatic refractive surgery candidates with a family history of corneal abnormality and confirmation of symptomatic corneal abnormality.

Setting:

University of Toronto, Toronto, Canada, provided patients and patient information. Avellino Lab USA, Inc., Menlo Park, CA, provided genetic testing and data analysis.

Methods:

A Canadian family of Italian descent with a history of corneal transplants over two generations was ascertained. Post-LASIK slit-lamp and OCT imaging of the proband and post-corneal injury slit-lamp images for a son were reviewed, and whole exome sequencing performed on DNA isolated from buccal swab samples from both. Presence of the mutation was confirmed by real-time PCR. Subsequently, buccal swab samples were collected from nineteen family members and DNA isolated for TGFBI mutational analysis to investigate the penetrance of the disease in this family and identify asymptomatic carriers of the identified mutation.

Results:

The proband revealed bilateral lattice-like deposits at the LASIK corneal flap interfaces. The son demonstrated lattice-like corneal changes in his injured right eye and an unremarkable left eye. A heterozygous TGFBI p.H626R (CAT>CGT) mutation was identified in both individuals. Fourteen of the nineteen family members, ranging from age 6 to age 92, were identified as carriers. Younger family members remain without lattice-like symptoms. The age of onset in this family varies from the third to the fifth decade of life.

Conclusions:

The TGFBI p.H626R mutation is associated with late-onset LCD with an average age of onset from the fourth to the fifth decade. LASIK surgeries are increasingly requested by younger adults, with the average age at surgery falling from 40 to 35. Since this is below the average age of disease onset, carriers present at pre-surgical screening with clear, symptom-free, healthy corneas. Without pre-LASIK genetic screening, these individuals risk post-surgical initiation of lattice corneal dystrophy. This family study reiterates the importance of performing genetic testing in both pre-LASIK surgery screening and in confirmation of symptomatic corneal abnormality diagnosis.

Financial Disclosure:

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