Corneal Dystrophy, Reis-Bücklers

Clinical Characteristics
Ocular Features: 

This is an anterior corneal dystrophy involving the epithelium and Bowman membrane.  Opacities consisting of spots and lines form in the central portion of the anterior cornea creating haziness with relative sparring of the periphery.  These can be seen as early as 4-5 years of age but few symptoms occur until the epithelium breaks down causing painful corneal erosions.  Visual acuity eventually drops as the corneal haze increases along with increasing irregularity of the epithelial surface.

Ultrastructural studies reveal degenerative changes in all epithelial cells and almost complete Bowman membrane replacement with disoriented collagen fibrils.

A comparative histological study of Reis-Bucklers and Thiel-Behnke dystrophies concluded that these are distinct CDB (corneal dystrophy Bowman) disorders and suggested the former be called CDB type I, and the latter CDB type II.  Type II is considered unique on the basis of the ‘curly’ fibers seen in the Bowman and subepithelial layers, while type I has bandshaped granular Masson-positive subepithelial deposits and ‘rod-shaped bodies’ resembling granular dystrophy.  Type I described here generally leads to greater vision loss than type II.

Systemic Features: 

No systemic disease is associated with Reis-Bucklers corneal dystrophy.

Genetics

This disorder seems to be closely related to the more common Thiel-Behnke dystrophy as the corneal disease is caused in both cases by missense mutations in the TGFBI gene on chromosome 5 (5q31). The mutation in Reis-Bucklers results in a p.Arg124Leu amino acid substitution whereas most cases of Thiel-Behnke dystrophy are the result of a p. Arg555Gln substitution.  Both disorders are inherited in an autosomal dominant pattern.

Treatment
Treatment Options: 

Ablation of the diseased cornea can improve vision and provide temporary relief from the erosions.

References
Article Title: 

Reevaluation of corneal dystrophies of Bowman's layer and the anterior stroma (Reis-Bücklers and Thiel-Behnke types): a light and electron microscopic study of eight corneas and a review of the literature

Kuchle M, Green WR, Volcker HE, Barraquer J. Reevaluation of corneal dystrophies of Bowman's layer and the anterior stroma (Reis-Bucklers and Thiel-Behnke types): a light and electron microscopic study of eight corneas and a review of the literature. Cornea. 1995 Jul;14(4):333-54. Review.

PubMed ID: 
7671605

References

Aldave AJ, Sonmez B. Elucidating the molecular genetic basis of the corneal dystrophies: are we there yet? Arch Ophthalmol. 2007 Feb;125(2):177-86. Review.

PubMedID: 17296893

Kuchle M, Green WR, Volcker HE, Barraquer J. Reevaluation of corneal dystrophies of Bowman's layer and the anterior stroma (Reis-Bucklers and Thiel-Behnke types): a light and electron microscopic study of eight corneas and a review of the literature. Cornea. 1995 Jul;14(4):333-54. Review.

PubMedID: 7671605

Kobayashi A, Sugiyama K. In vivo laser confocal microscopy findings for Bowman's layer dystrophies (Thiel-Behnke and Reis-Bucklers corneal dystrophies). Ophthalmology. 2007 Jan;114(1):69-75.

PubMedID: 17198850