INVESTIGATION OF SMALL VESSEL ANATOMY BY SCANNING ELECTRON-MICROSCOPY OF RESIN CASTS - DESCRIPTION OF THE TECHNIQUE AND EXAMPLES OF ITS USE IN THE STUDY OF THE MICROVASCULATURE OF THE PERITONEUM AND BILE-DUCT WALL

  • 1 January 1980
    • journal article
    • research article
    • Vol. 130  (JAN) , 43-54
Abstract
Scanning electron microscopy (SEM) of microvascular resin casts has provided an excellent alternative technique to light microscopy in studying serial sections or injected, cleared tissue of the microvasculature. A method for producing such casts is described here, and the 1st use of the technique in human microvascular research is recorded. Anatomical specimens were taken from fresh human and animal cadavers as part of a study of bile duct blood supply. Unsaturated polyester resin was injected via the major vessels using hand-held syringes, until a flush on the surface of the tissue indicated capillary filling. After curing and maceration, the specimens were cleaned with great care using a gentle water jet. Small portions of the casts were removed, thoroughly washed and mounted on aluminum stubs. After air drying they were coated with carbon and gold prior to SEM inspection, which included preparation of stereo pairs. As all vessels including capillaries were perfused with resin, complete organ replication was achieved. Light microscopy of the capillary casts did not provide adequate depth of focus, but SEM revealed spatial relationships within microvascular networks with great clarity. Human visceral peritoneum contained a capillary plexus made up of long, straight vessels in two layers at right angles to each other. The capillaries of bile duct mucosa outlined pits which covered the mucosal surface. Stereo pairs were especially useful in the study of this undulating surface. No reports were found in the literature referring to the previous use of this technique in human microvascular research. Bile duct mucosa is supplied by a capillary plexus arising from an anteriolar net within the duct wall, and produced the 1st description of the microvascular pattern within visceral peritoneum. The technique is a valuable tool that deserves wider application in both human and animal anatomical research.