CO2 laser surgical methods facilitate a precise incision in small tissue areas without physical tissue contact. Decreased intraoperative hemostasis, higher peak vertical forces, faster weight-bearing, and decreased discomfort have been associated with laser onychectomy procedures. However, safety and price considerations still limit widespread CO2 use in veterinary medicine. Radiofrequency (RF) units deliver radiowave energy to tissues at low temperature, low voltage, and high frequency; RF has been associated with lower thermal damage than the CO2 laser.

Collateral tissue damage created by RF or the CO2 laser was examined in 6 healthy cats after elective feline onychectomy procedures. Onychectomy procedures were performed with RF on 12 limbs on the right side, including 54 digits (30 front and 24 rear). Procedures were performed with the CO2 laser on 12 limbs on the left side, including 54 digits (30 front and 24 rear). Cats 1 and 2 were euthanized on the first postsurgical day, cats 3 and 4 on the third day, and cats 5 and 6 on the seventh day. Intact distal limbs were submitted for analysis; 4 limbs (18 digits) were collected postoperatively for each surgical technique at each time period. Total lesion width; total necrosis width; and edema, hemorrhage, and inflammation scores were assigned to each digit. Incisional bridging by granulation tissue and reepithelialization degree were also scored.

In this study, few differences in collateral tissue damage were identified between the RF and CO2 laser techniques. However, greater incisional bridging by granulation tissue was noted with RF, suggesting that RF is an appropriate alternative to the CO2 laser with regard to collateral tissue damage and bridging of the incision by granulation tissue. In addition, RF is not accompanied by the strict safety considerations and initial expense of acquisition of a CO2 laser.

Commentary: This provides significant clinical support for the use of the RF unit in routine clinical practice, particularly for onychectomy procedures. RF has many advantages, including decreased expense and less stringent safety regulations, and collateral tissue damage was comparable to that elicited by the CO2 laser. In addition, greater incision bridging by granulation tissue was seen with RF in this study. However, RF may be associated with increased hemorrhage. Future studies with larger sample sizes will characterize this. Onychectomy procedures are among the most common procedures performed in clinical practice, and characterization of the most optimal surgical techniques would be highly beneficial to patient and clinician alike.—Indu Mani, DVM, DSc

 Comparison of the carbon dioxide laser and the radiofrequency unit for feline onychectomies. Burns SM, Howerth EW, Rawlings CA, et al. JAAHA 46:375-384, 2010.