EFFICACY OF HIGH-DOSE AMINO-ACID SOLUTION ON SPINAL-CORD INJURY-INDUCED BY FOCAL ND-YAG LASER IRRADIATION

In this experimental study, a neodymium: yttrium-aluminium-garnet (Nd: YAG) laser was used to induce highly reproducible focal spinal cord le sions in anaesthetized guinea pigs. The efficacy of high dose amino ac id solution (HDAAS) on this injury is investigated. Experiments were p erformed on 36 animals divided into three groups; sham operated contro ls, laser irradiated surgical controls, and amino acid groups. Acute r esponses to injury were evaluated with somatosensory (SSEP) and motor evoked potentials (MEP) and functional recovery was assessed for 8 wee ks using the inclined plane technique. In the laser irradiated surgica l control group, MEP disappeared one hour after the laser injury, but SSEP revealed changes of amplitude and latency. In this group, the ave rage value of the inclined plane at 24 hours after the laser applicati on was 45.3 +/- 1.4 degrees. In the amino acid group, at the sixth hou r of injury, MEP and SSEP changes improved with infusion of HDAAS for 4 hours. This improvement was statistically significant (for latency o f SSEP U = 140 p < 0.05). Inclined plane value at 24 hours after the l aser application was 65.5 +/- 1.2 degrees in this group. This study sh owed that application of Nd:YAG laser irradiation on the spinal cord i nduced spinal cord injury which presented as paraparesis, HDAAS may pr ovide significant therapeutic protection in secondary damage following this injury and may have a potential role in the treatment of acute s pinal cord injury.