Anti-scarring effect of sodium hyaluronate at filtration pathway after filtering surgery in rabbits

To investigate the anti-scarring effect of sodium hyaluronate (HA) at filtration pathway after filtering surgery in a rabbit model.

Fifteen healthy adult New Zealand white rabbits were selected for trabeculectomy in both eyes. The right eyes were used as HA group with 0.1 mL HA injected into the anterior chamber at the end of the operation; the left eyes were used with 0.1 mL sodium lactate Ringer's solution (RS) injected into the anterior chamber as RS group. Intraocular pressure (IOP), filtering blebs morphology, inflammatory reaction and complications were observed at the 7, 60, and 90d after surgery.

One day after surgery, the IOP of HA and RS groups were 12.75±1.92 and 10.50±1.59 mm Hg (P=0.005). At the 7^th day postoperative, the filtering blebs of each group were functional type and TGF-β expression was significantly difference in both groups (0.10±0.01 vs 0.14±0.02, P=0.024). After 60d of the operation, all filtering blebs were scarring and alpha-smooth muscle actin (α-SMA) expression was significantly difference in both groups (0.40±0.04 vs 0.35±0.02, P=0.032). α-SMA positive cells were mainly distributed in the junction of conjunctiva and sclera and around the blood vessels. The collagen volume fraction (CVF) of HA and RS group was (75.49±7.01)% and (79.93±5.35)% (P=0.044). On the 90^th day after the operation, CVF was (82.57±5.19)% and (88.08±1.75)% in HA and RS groups (P=0.036). There was no α-SMA positive cell in HA group, while a few positive cells were observed in RS group (P=0.000).

HA has effect of anti-scar and anti-inflammation on filtration pathway after filtering surgery within 3mo by inhibiting fibroblast proliferation and collagen deposition.