Comparative study of laser and scalpel nerve transections

Abstract

This investigation was designed to compare standard scalpel transections of the tibial branch of the rat sciatic nerve with those performed using either a milliwatt carbon dioxide (CO2) or a potassium titanyl phosphate (KTP/532) laser. Four transection groups consisted of nerves sectioned with (1) scalpel (control), (2) milliwatt CO2 laser, (3) KTP/532 with microscope attachment, and (4) KTP/532 laser with 400-microns bare fiber. Each laser was used with the same parameters: 10 watts, 0.4-mm spot size, and continuous-wave mode. Horseradish peroxidase (HRP) was applied to the proximal stump for 30 min, and the animals were sacrificed 24 h later. Horseradish peroxidase (HRP)-labeled motoneuron cell bodies in the lumbar spinal cord were then counted. The average numbers of labeled neurons in each group were as follows: group I (n = 14) 518, group II (n = 8) 424, group III (n = 8) 351, and group IV (n = 8) 283. The standard deviations were quite large, however. When all laser transections were pooled and compared with paired scalpel transections, we found a significant difference, both by the paired t-test (P = 0.016) and by the Wilcoxon matched-paired test (P = 0.02). We conclude that laser transection significantly diminishes the number of neurons labeled by the retrograde transport of HRP.

Evaluation of short-term limb function following unilateral carbon dioxide laser or scalpel onychectomy in cats

“…This phenomenon is not unique to veterinary medicine because the use of a CO 2 laser for surgical procedures of the head and neck in humans appears to result in less postoperative pain than procedures performed with a scalpel or electrocautery. 32 In 1 study, transection of the tibial branch of the sciatic nerve in rats with a CO 2 laser resulted in a significant decrease in the retrograde transport of horseradish peroxidase, compared with a scalpel group. 32 Although these results may support the suggestion that a decrease in postoperative pain with laser onychectomy is the result of decreased initiation of action potential at the transected nerve ending, 30 similar findings in a feline onychectomy model have not been reported; thus, the clinical relevance of such findings remains unclear.…”

“…32 In 1 study, transection of the tibial branch of the sciatic nerve in rats with a CO 2 laser resulted in a significant decrease in the retrograde transport of horseradish peroxidase, compared with a scalpel group. 32 Although these results may support the suggestion that a decrease in postoperative pain with laser onychectomy is the result of decreased initiation of action potential at the transected nerve ending, 30 similar findings in a feline onychectomy model have not been reported; thus, the clinical relevance of such findings remains unclear. In another study, 33 incisions made in the dorsal surface of a rat tongue with cautery, a scalpel, and a CO 2 laser in both continuous and pulsed modes were compared immunocytochemically to normal, unoperated tissue.…”

Effect of Nerve-Cutting Technique on Nerve Microstructure and Neuroma Formation

“…Currently, a wide variety of nerve-cutting techniques are used in the operating room during procedures involving ner ve repair, neuroma excision, and amputation. [9][10][11][12][13][14][15][16] These range from sharp transection techniques (nerve-cutting guide forceps with straight razor, fresh scalpel blade) to techniques using various surgical scissors to nerve transection with cautery. Sharp transection techniques are thought to decrease symptomatic neuroma formation by uniformly limiting nerve fiber outgrowth whereas proponents of electrocautery believe that it decreases symptomatic neuroma formation by inducing a Sunderland fourth-degree injury, thus resulting in little to no functional recovery.…”

Quantitative Evaluation of Intact Peripheral Nerve Structures after Utilization of CO2Laser, Electrocautery, and Scalpel

“…However, some investigators suggest that there is specific reaction to the action of the laser. 1 The extent of the interaction between lasers and tissues is generally determined by the wavelength of the laser light and by the optical properties of each tissue. The skin and the mucosa possesses a layered structure, and each layer has different diffusion properties through the thickness of the tissue.…”