Corneal Opacity Induced by Light in a Mouse Model of Gelatinous Drop-Like Corneal Dystrophy

Introduction: Corneal disease, especially infective keratitis, is one of the major causes of visual impairment and blindness in developing countries. Objective: To find out the current indications for keratoplasty, how these indications have changed over time as well as how they are different from those in other parts of the world. Materials and methods: A retrospective study of a case series of 645 keratoplasty surgeries (589 patients) was conducted at the Tilganga Institute of Ophthalmology from January 2005 to December 2010. Outcome measures: The cases were evaluated in terms of demographic parameters, preoperative diagnosis and the type of surgery performed. Results: The most common indication for surgery was active infectious keratitis (264 eyes, 40.9 %), followed by corneal opacity (173 eyes, 26.8 %), regraft (73 eyes, 11.2 %), bullous keratopathy (58 eyes, 9.0 %), keratoconus (45 eyes, 7.0 %) and corneal dystrophy (11 eyes, 1.7 %). The mean recipient age was 41.7 ± 19.9 years with over a half of the patients between 15 to 49 years of age. More men (64.1 %) underwent keratoplasty than women (35.8 %). 59.8 % of the eyes with infectious keratitis had a perforated corneal ulcer. 49.7 % of corneal opacities were due to previous infectious keratitis. 72 % of regrafts were for endothelial failure of various causes. In older patients (> 50 years), bullous keratopathy was an important indication, after infectious keratitis. Keratoconus and corneal scar were major causes of keratoplasty in children of 14 years or less. Four percent of the patients had keratoplasty in both the eyes. 17.1 % of the patients who had one eye operated on had a blind fellow eye with a vision of less than 3/60. Conclusion: Currently, keratitis, either active or healed, is the major indication for keratoplasty, suggesting that improved primary eye health care is necessary to decrease the prevalence of corneal blindness. Nepal J Ophthalmol 2013; 5(10): 207-214 DOI: http://dx.doi.org/10.3126/nepjoph.v5i2.8730

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Corneal Dystrophy in Dutch Belted Rabbits as a Possible Model of Thiel-Behnke Subtype of Epithelial-Stromal TGFβ-Induced Corneal Dystrophy

Toxicologic Pathology ◽

10.1177/0192623320968092 ◽

2020 ◽

pp. 019262332096809

Author(s):

JoAnn C. L. Schuh ◽

Dana L. Holve ◽

Karen E. Mundwiler

Keyword(s):

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Corneal Opacity ◽

Corneal Dystrophy ◽

International Committee ◽

Corneal Dystrophies ◽

Transmission Electron ◽

Oct Imaging ◽

Small Clusters

The International Committee for Classification of Corneal Dystrophies (IC3D) categorized corneal dystrophies in humans using anatomic, genotypic, and clinicopathologic phenotypic features. Relative to the IC3D classification, a review of the veterinary literature confirmed that corneal dystrophy is imprecisely applied to any corneal opacity and to multiple poorly characterized histologic abnormalities of the cornea in animals. True corneal dystrophy occurs in mice with targeted mutations and spontaneously in pet dogs and cats and in Dutch belted (DB) rabbits, but these instances lack complete phenotyping or genotyping. Corneal dystrophy in DB rabbits can be an important confounding finding in ocular toxicology studies but has only been described once. Therefore, the ophthalmology and pathology of corneal dystrophy in 13 DB rabbits were characterized to determine whether the findings were consistent with or a possible model of any corneal dystrophy subtypes in humans. Slit lamp and optical coherence tomography (OCT) imaging were used to characterize corneal dystrophy over 4 months in young DB rabbits. The hyperechoic OCT changes correlated with light microscopic findings in the anterior stroma, consisting of highly disordered collagen fibers and enlarged keratocytes. Histochemical stains did not reveal abnormal deposits. Small clusters of 8 to 16 nm diameter curly fibers identified by transmission electron microscopy were consistent with Thiel-Behnke (TBCD) subtype of epithelial-stromal transforming growth factor β-induced dystrophies. Sporadic corneal dystrophy in DB rabbits appears to be a potential animal model of TBCD, but genotypic characterization will be required to confirm this categorization.

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