Effect of basic fibroblast growth factor and transforming growth factor β1 on the healing of reconstructed dura by carbon dioxide laser soldering in minipigs

Background  Carbon dioxide (CO₂) laser soldering is an alternative technique for tissue bonding. Basic fibroblast growth factor (bFGF) and transforming growth factor β₁ (TGFβ₁) are two key factors for wound healing. This study was performed to demonstrate the efficacy of CO₂ laser soldering for dural reconstruction and the effect of bFGF and TGFβ₁ on healing.

Methods  In Part I, 10 minipigs were randomized into two equal groups. Dural defects were reconstructed by conventional fibrin glue bonding (group I_a) or CO₂ laser soldering (group I_b). The reconstructed dura was subjected to burst pressure (BP) measurement and immunohistochemical staining after 1 week. In Part II, 36 minipigs were randomized into three equal groups. Dural reconstruction was achieved by CO₂ laser soldering. Exogenous bFGF (group II_b) or TGFβ₁ (group II_c) was administered while group II_a served as a control group. The specimens were subjected to BP measurement after 1, 2, 3, and 4 weeks, respectively.

Results  In Part I, the dura specimens displayed positive staining of only bFGF in group I_a and of both bFGF and TGFβ₁ in group I_b. Group I_b showed higher BP than group I_a ((98.00±21.41) mmHg vs. (70.80±15.09) mmHg, respectively; P <0.05). In Part II, BP of group II_c was significantly higher than that of group II_a (P <0.01). The BP of group II_a trended toward stabilization after 3 weeks of growth, while that of groups II_b and II_c trended toward stabilization after 2 weeks of growth.

Conclusions  CO₂ laser soldering is a reliable technique for dural reconstruction. The superior healing of dural reconstruction by CO₂ laser soldering may be related to higher expression of bFGF and TGFβ₁, and CO₂ lasers may stimulate their secretion. Exogenous bFGF or TGFβ₁ may improve healing by shortening the wound healing time, and exogenous TGFβ₁ may improve the tensile strength.