PATHOLOGY
Pathologically, both the hyaline deposits typical of granular dystrophy and the amyloid deposits typical of lattice dystrophy are seen. These lesions extend from the basal epithelium to the deep corneal stroma. Individual opacities stain with the Masson trichrome or Congo red stain. The deposits appear as rod-shaped bodies on electron microscopy; randomly aligned fibrils of amyloid are also seen. Findings on confocal microscopy are a combination of those seen in GCD1 and LCD.
CLINICAL PRESENTATION
Affected patients have a granular dystrophy both histologically and clinically, with shorter, whiter lattice lesions in addition to the granular lesions. Clinical findings in GCD2 differ from those in GCD1. Stellate-shaped, snowflake-like, and icicle-like opacities appear between the superficial stroma and midstroma (Fig 7-12). Lattice lines are also seen deeper than the snowflake opacities. Older patients have anterior stromal haze between deposits, which reduces vision. Pain may occur with mild corneal erosions.
MANAGEMENT
Lamellar or penetrating keratoplasty may be useful, depending on the depth of the deposits. PTK may be considered as an alternative to reduce surface irregularity and increase corneal clarity. Laser in situ keratomileusis (LASIK) and PRK are contraindicated.
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Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.