Abstract
Purpose:
To investigate the histopathology of the foreign body reaction (FBR), and the effect of aqueous humor on it in glaucoma drainage implant surgery
Methods:
A glaucoma drainage device (Ahmed glaucoma valve) was implanted into 20 New Zealand white rabbits. We monitored the histopathology of blebs at microscopic levels from 2-days to 8-weeks postoperatively. Hematoxylin and eosin staining, Masson’s trichrome staining, anti-actin and α-smooth muscle immunofluorescence staining, and anti-proliferating cell nuclear antigen immunohistochemistry were performed. To observe effects of aqueous humor on FBR, we designed two implant models. One group received a plate with a tube placed in the anterior chamber (experimental group), while the other received the plate cut from the tube (control group).
Results:
Foreign body giant cells were found along the inner border of blebs, and the innermost layer of bleb demonstrated a densely packed collagenous stratum in both groups. The number of foreign body giant cells was suppressed in the experimental group compared to the control group (P < 0.001). Fibroblast division was more active in the experimental group than in the control group. Masson’s trichrome staining demonstrated that the innermost avascular collagenous layer was much thicker in the experimental group than in the control group (P = 0.021). The extent of α-SMA staining was greater in the experimental group than in the control group.
Conclusions:
In the aqueous humor environment, wound healing around a glaucoma drainage implant revealed the unique FBR with the relatively small number of foreign body giant cells and reinforced fibrotic encapsulation.
Keywords: 765 wound healing •
637 pathology: experimental •
427 aqueous