[Scanning electron microscopy study of the synovial membrane in rheumatoid arthritis].

A comparative study under the scanning electron microscope of rheumatoid synovial membranes, 5 arthrosic synovial membranes, one tuberculous membrane, and 3 normal synovial membranes showed the pathological changes in the synovial membrane due to rheumatoid arthritis: Inflammatory aspect of the synovial fringes, surrounded by turgid and proliferative villous processes. Granular appearance of the endo-articular surface like a "pebble beach". Dome-shaped synoviocyte layer, standing out well above the subjacent intimal layer, associated with small round cells, also with a raised margin, covering most of the endo-articular surface. Plasma membrane of the superficial synovial cells, covered with numerous and various differentiations and abundant microvillous processes. Reticular deposits or layers, covering the apical poles of the synoviocytes.