Corneal Dystrophies: A Clinical, Pathological, and Surgical Approach

Ultrastructural Changes in Lattice Dystrophy of the Cornea

“…There may be a granular matrix with many polyribosomes and a prominent rough endoplasmic reticulum [Hogan andA lvarado, 1967: Klintworth, 1967;Wobmann and Lalive d'EpiNAY, 1974]. Many lysosomes may also be found, myelin bodies [Benko and Bauer, 1970], as well as vacuoles with a fibrillar or granular content [Benko and Bauer, 1970: Pouliquen et al, 1973: Wobmann and Lalive d'EpiNAY, 1974, which are suggestive for progressive degeneration [Hogan and A lvarado, 1967;Malbran, 1972: Pouliquen et al, 1973Wobmann and Lalive d'EpiNAY. 1974], Intracytoplasmic groups of micro fibrils may be found, which are separated from the extracellular deposits by the cell membrane [Pouliquen et al, 1973: Wobmann andLalive d'EpiNAY, 1974].…”

“…These deposits are homogeneous [Pouliquen et al, 1973], finely granular [Pouliquen et al, 1973] or fibrillar with at random oriented fibrils [Klintworth, 1967;Bowen et al, 1970;Wobmann and Lalive d 'EpiNAY, 1974], The average diameter of these fibrils is 80-100 A [Mac Tigue and F ine, 1964;M ac Tigue, 1967;Hogan and A lvarado, 1967;Klintworth, 1967;Bowen et al, 1970;Malbran, 1972;Pouliquen et al, 1973;Wobmann and Lalive d'EpiNAY, 1974], and between them some col lagen fibrils may be found [Klintworth, 1967;Malbran, 1972], The fibrils may have a general direction parallel to the original collagen fibrils, but the individual fibrils may also be obliquely intermingled.…”

“…According to Pouliquen et al [1973] these microfibrils are not due to a phagocytosis, as they are not inside vacuoles, but they could be due to an intracellular production of amyloid or to a collagenolytic substance. Around the keratocytes accumulations of electron-dense material are, indeed, fre quently found [Klintworth, 1967;Malbran, 1972;Pouliquen et a i, 1973], which may have a homogeneous, finely granular or fibrillar appearance [Klintworth, 1967;Pouliquen et al, 1963;Wobmann and Lalive d'Epinay, 1974]. These fibrils measure approximately 100 A in diameter [Pouli quen et al, 1973], However, this homogeneous or fibrillo-granular material is not specific for lattice dystrophy, since it is also found around the keratocytes of a normal cornea Pataa et al, 1970;H amada et al, 1972], in cornea guttata [Pouliquen et al, 1971;K anai and K aufman, 1971], in keratoconus [Pouliquen et al, 1968;Robert e ta l, 1970;P ataa et al, 1970], in congenital corneal dystrophy [Babel et al, 1969], in corneal oedema [Goldmann et al, 1968;K anai et al, 1971], in opaque grafts from metaherpetic keratitis , in Hurler's disease , in crystalline corneal dystrophy [Babel et al, 1973], and in buphthalmos [Pouliquen and Saraux, 1967], According to these authors the material could be due either to fibrillolysis or to fibrillogenesis, the dia meter of the fibrils being approximately 150 A .…”

“…According to Malbran [1972], F rançois and Victoria-Troncoso [1974], the lysosomes of the keratocytes contain enzymes which act on the mucopoly saccharides. When the primary lysosome loses its membrane the enzymes diffuse in the cytoplasm, and produce a lysis of the cells, their contents being deposited in various places.…”

Corneal stromal dystrophies: a clinical pathologic study

“…Most cases of CD have an autosomal dominant inheritance pattern, starting at the first decades of life, with a stable or slowly progressive course (1,2) . Corneal dystrophies (CDs) are classified according to the involved corneal layer.…”