Current concepts on the ultrastructural pathogenesis of macular and lattice corneal dystrophies.

Some thoughts on the ultrastructural genesis of the lesions in macular and lattice corneal dystrophy are reviewed. These two genetically determined diseases of the cornea are symbolized by two chemical complexes, namely glycosaminoglycans and amyloid; they raise many questions about the biologic behavior of the cornea and its constituent cells and matrix stroma. Though the lesions in these two diseases appear to be localized to the cornea, the possibility of other tissues and organs being involved cannot be excluded at present, particularly when one takes into account that adequate postmortem studies have not yet been performed on patients with macular or lattice corneal dystrophy. To distinguish lattice corneal dystrophy from other disorders of the cornea which also contain amyloid, the term primary hereditary corneal amyloidosis is proposed. This terminology would seem appropriate in view of the fact that not all affected members of a family develop lesions with a lattice pattern.