Honeycomb-shaped corneal dystrophy of Thiel and Behnke. Reclassification and distinction from Reis-Bucklers' corneal dystrophy

Background The honeycomb-shaped dystrophy of Thiel and Behnke has been misu nderstood for a long time and has erroneously been classified as Reis-Buckl ers' dystrophy. The mistake originates in historical misunderstandings conc erning the interpretation of the original Reis-Bucklers' dystrophy, which r esults in a nonuniform nomenclature and a permanent confusion in the evalua tion of the superficial stroma dystrophies. This paper intends to clarify t he original identity of the honeycomb corneal dystrophy and to distinguish it from the Reis-Bucklers' dystrophy. Patients and methods We examined seven patients of the original family of T hiel and Behnke. Five of them were newly detected, two of them were reexami ned. The histological findings were reevaluated, and the diagnosis was prov ed by electron microscopic study of corneal specimens. Results The honeycomb dystrophy is characterized by: (1) dominant inheritan ce, (2) early manifestation, (3) slow progression, (4) painful erosions dur ing childhood, (5) subepithelial corneal opacities with a clear limbal zone , (6) honeycomb-shaped opacity pattern, (7) recurrence in the graft followi ng keratoplasty, (8) subepithelial fibrous tissue in wave-like accumulation in histologic sections, (9) curly filaments observed by electron microscop y. The clinical symptoms hardly differ from those of Reis-Bucklers' dystrop hy. The histological appearance, however, is clearly distinct and curly fil aments are the pathognomonic ultrastructural features. Conclusions The honeycomb dystrophy represents a definite corneal disease. The terms "Reis-Bucklers' dystrophy" and "ring dystrophy" used for it up to now are wrong and should be eliminated in this context. The only correct t erm of the disease is honeycomb-shaped dystrophy (Thiel-Behnke) according t o its first description and major clinical features. The eponym Reis-Buckle rs' dystrophy should only be used for the corneal dystrophy described by Re is and Bucklers.