Vacuum injection--a new indirect fixing method for the demonstration of initial lymphatics in biopsy specimens of human organs.

With the indirect vacuum injection method (IVIM) at a negative pressure of 30 kPa, it is possible to demonstrate the initial lymphatics (IL) by scanning electron microscopy even in biopsy specimens of various organs (minimum size 0.5 X 0.5 cm2). IL can also be dilated and fixed using the indirect perfusor injection method (IPIM), but only in larger specimens (minimum size 2.0 X 2.0 cm2). Only dilated IL can be examined by scanning electron microscopy, and only the IL of the ampulla of the Fallopian tube can be reliably dilated during immersion fixation. The quality of fixation on use of the vacuum technique conforms to the standard achieved with other methods. No one has yet succeeded in demonstrating the IL in biopsy specimens smaller than mentioned above using any of the methods described.