The Morgagnian and Brunescens cataract morphology studied with with SEM and TEM.
The Morgagnian cataract lenses--pre-fixed with GA for SEM & TEM and post-fixed with tannic-acid-arginine-OsO4 for SEM and OsO4/K4Fe(CN)6 for TEM after staining with Ur-acetate/Pb-citrate--showed areas in the cortex with radial instead of concentric running lens fibres, degeneration of lens fibres with vacuoles and defected "ball & socket" connections. The presence of oval/spherical bodies of 0.5-20 microns was acknowledged, the largest of them having a golf-ball appearance and originating from the cytoplasm of the degenerating lens fibres; the smallest of them with an approximate size of 0.2-0.5 micron seemed to be formed by budding off from the microvilli of the furrowed lens epithelium. The Brunescens cataract lenses showed at low magnification no difference between lens fibres from the cortical area and the nucleus. The disintegration process of the lens fibres was observable as degradation of the ball & socket system and the existence of holes in the lens fibre body and emerging of spherical bodies from the cytoplasm. The globular structures seemed to be covered with a thin coating and were partly filled with a low density membranous-like material. In TEM-sections of the cataractous lens aterial vacuoles were visible consisting of a large number of smaller globules with a contents of low contrast low density membranous-like material, comparable with the globular structures seen in SEM.
Lab. Histology & Cell Biology, University of Groningen, The Netherlands.
W L
WL
Jongebloed
D
D
Kalicharan
L I
LI
Los
J G
JG
Worst
D002386:Cataract / Q000145:classification / Q000473:pathology*; D002462:Cell Membrane / Q000648:ultrastructure; D004848:Epithelium / Q000648:ultrastructure; D006801:Humans; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008871:Microvilli / Q000648:ultrastructure; D014617:Vacuoles / Q000648:ultrastructure