Vein graft with fat tissue/laser application in peripheral nerve regeneration

Objective: This study investigated whether the use of vein graft fulfilled with fat tissue and/or the Low-Power Laser application improves nerve regeneration.

Method: Thirty-seven male Wistar rats (age 12 weeks) were randomly allocated into five groups: (1) Control Group (CG, n = 5); Experimental Groups treated with vein graft (2) without Fat Tissue (EG, n = 8); (3) with Fat (EGF, n = 8); (4) without Fat and with Laser Therapy (EGL, n = 8); (5) with Fat and Laser Therapy (EGFL, n = 8). In the experimental groups a gap (0.5 cm) was created in the peripheral nerve (sciatic nerve). This gap was immediately treated with a venous (external jugular) graft filled or not with fat tissue. The laser was applied three times a week (90s each) for 6 weeks. Animals were euthanized 150 days after surgery. Morphometry of the peripheral nerve was obtained from 220 sections per animal. The data were tested using ANOVA and Tukey's test (p<0.05).

Result: The use of vein graft with fat and/or the laser application lead a significant better nerve regeneration, considering the fiber area and diameter, myelin sheath area and thickness parameters, compared to the treatment with vein graft only. The association between the vein graft with fat and the laser application enhanced the regeneration for all parameters (including also axon diameter and area). The treatment EGFL significantly enhanced in 2-fold and about 3-fold the fiber diameter (6.94±0.43 µm²) and the myelin thickness (4.04±0.37 µm²) compared to EG (3.43±0.37 and 1.45±0.22 µm², respectively).

Conclusion: The use of the vein graft fulfilled with fat tissue and the Low-Power Laser application enhance the nerve regenerative processes.