Figure 1.
Subcutaneous implant retrieval (surgery site 1).
Optical images of (a) clear and (b) pigmented aerogel implants being retrieved after twenty months of subcutaneous incubation in Sprague-Dawley rats. Arrows indicate the embedded implants. A mild fibrosis can be observed for both pigmented and clear PCSA implants. The pigmented aerogel samples were much easier to identify compared to the clear implants.
Figure 2.
Stain uptake by PCSA sections.
H&E stain uptake by 5 µm thick sections of (a) clear and (b) pigmented aerogel samples. The out-of-focus regions of the image (indicated by arrows) reflect the three dimensional nature of the aerogel material. While the pores cannot be visualized by a light microscope, the darker regions are interpreted as openings to the three dimensional porous structure. Images were taken with an upright Nikon Eclipse 800 microscope. Striations noticed in (a) are attributed to sectioning artifacts.
Table 1.
Summary of short and long term effect of subcutaneous aerogel implant on local tissue.
Table 2.
Summary of the effect of intramuscular aerogel implant on local tissue.
Figure 3.
Histological evaluation of the short-term effect of subcutaneous PCSA implants on nearby tissue.
Histology of pigmented aerogel implant extracted after two weeks and stained with methylene blue/basic fucshin. (a) All of the aerogel implant at X 2 magnification, (b) X 20 magnification for spot 1, (c) X 20 magnification of spot 2 and (d) X 10 magnifications of spot 3. A mild fibrosis is observed but no inflammation. Images were taken with an Olympus BX51 microscope.
Figure 4.
Histological evaluation of the long-term effect of subcutaneous PCSA implants on nearby tissue.
Histology of (a) clear and (b) pigmented aerogel implant extracted after seventeen months of subcutaneous incubation in Sprague-Dawley rats and stained with H&E. A mild fibrosis is observed but no inflammation. The dotted line outlines the boundary between PCSA and nearby tissue.
Figure 5.
High magnification images of aerogel-muscle interface, intramuscular implantation.
Histology of (a) clear and (b) pigmented aerogel implants extracted after seven months of IM incubation. At the interface between aerogel and muscle a mild fibrosis is observed but no inflammation. Darker regions seen on the aerogel side are associated with the three dimensional, no-planar structure of aerogel. Images were taken with a Nikon Eclipse 800 microscope.
Table 3.
Summary of long term effect of intramuscular and subcutaneous aerogel implants on organs.