[Unilateral type III (Hida) lattice stromal corneal dystrophy]

All three types of lattice stromal dystrophy of the cornea use to appear bilaterally. We report on two patients with an unilateral manifestation of type III.

A 54 and a 87-years-old man presented a strictly unilateral atypical lattice dystrophy of the cornea and suffered from corneal erosion. Strikingly thickened lattice lines were predominantly orientated radially, almost reached to the corneoscleral limbus and were located in the anterior and midstroma. Both patients had no affected family members and there was no indication on general amyloidosis.

After successful penetrating keratoplasty histological examination showed remarkably large amyloid deposits predominantly located close to Bowman's layer or in the midstroma and a discontinuous band of amorphous material beneath the intact Bowman's layer. Electron microscopy disclosed that the deposits were composed of typical amyloid fibrils. Four years later the younger of the two patients developed a corneal opacification being suggestive of early stage of lattice dystrophy in the other eye.

Lattice corneal dystrophy type III, as described by Hida et al. in 1987, is easily diagnosed at the slit lamp. It may manifest itself unilaterally. In contrast to Meretoja's syndrome, there is no systemic involvement.