Comparative study of acute tissue damage induced by the CO2 laser versus microelectrodes in cordectomies

Acute tissue damage induced by monopolar microelectrodes and radiofrequency in vocal cords after transoral cordectomy

INTRODUCTION

In 2006 and 2009, we reported the levels of acute and chronic tissue damage after cordectomy associated with use of the microlectrodes using high frequency energy. In 2010, we shifted to radiofrequency rather than high frequency electrogenerators.

OBJECTIVE

The aim of this study is to evaluate acute tissue damage in the larynx after cordectomy using microelectrodes coupled to a radiofrequencygenerator.

METHODS

We studied 22 patients with a stage T1 glottic squamous cell carcinoma. The patients were randomly assigned to the two operating mode: cutting or coagulation (11 patients each mode). The strength of the study is that there are no previous studies on the effect of radiofrequency in human vocal cord.

RESULTS

Tissue damage was milder when microelectrodes were coupled to a 4 MHz generator operating in the cutting mode. Thus, when using microelectrodes and radiofrequency, we recommend that the cutting mode be used for epithelial incision and the coagulation mode to treat the stroma and muscle and for final hemostasis.

CONCLUSION

Microelectrodes and radiofrequency in transoral laryngeal surgery produced mild tissue damage and offer an excellent alternative to the use of high frequency energy.

Healing process following laser cordectomy of early glottis carcinoma from endoscopic view

BACKGROUND AND OBJECTIVE

Transoral laser surgery is useful for treating early glottic carcinoma. Wound areas after carbon dioxide (CO2 ) laser surgery are not covered by flaps, delaying healing. The healing process following laser cordectomy is not well understood. In this study, laryngoscopes were used to monitor the normal healing process after laser cordectomy and to determine if there was residual or recurrent disease.

MATERIALS AND METHODS

This prospective case study included 36 patients who underwent CO2 laser surgery for early glottis carcinoma between January 2011 and June 2014 at a university tertiary referral center. Postoperative complications, oncologic results, and mucosal stabilization time were analyzed. Vocal fold stabilization was defined as an absence of gross changes during two consecutive follow-up examinations.

RESULTS

The 3-year overall survival rate was 100% and the 3-year local control rate was 94%. Vocal cord stabilization was observed in 29 patients at a mean 88.1 days, with stabilization associated with the type of cordectomy (P < 0.05). During the wound-healing process, two patients experienced local recurrences. One had a persistent white patch for over 4 months and the other presented with a new mass in a non-operated area. Biopsies of both lesions showed recurrent disease. Postoperative complications included granulation in two patients and anterior commissure adhesion in one.

CONCLUSION

CO2 laser microsurgery is an effective treatment for early glottis carcinoma. Close attention should be paid to delays in healing process after laser surgery. Interventions should be considered for patients with abnormal laryngoscopic appearance or overly prolonged healing. Lasers Surg. Med. 48:483-489, 2016. © 2016 Wiley Periodicals, Inc.

Radiofrequency dissection versus 'knot tying' in conventional total thyroidectomy

OBJECTIVE

To evaluate the safety and effectiveness of radiofrequency dissection in conventional 'open' total thyroidectomy.

METHODS

Thirty-nine patients scheduled for conventional total thyroidectomy were included in a prospective randomised study. Patients were randomly assigned to one of two groups: a radiofrequency dissection method was used in one group, and a knot tying technique was used in the other.

RESULTS

Significantly fewer surgical instruments and materials were required for the radiofrequency dissection group than the knot tying group (p < 0.01). There were no significant differences between the two groups in mean operative time, blood loss, post-operative drainage and pain, recurrent palsy, and hypocalcaemia (p > 0.05).

CONCLUSION

Radiofrequency dissection is a safe alternative to the knot tying technique, and enables a significant reduction in the number of surgical instruments required for the operation.

Use of lasers in laryngeal surgery

Lasers are a relatively recent addition to laryngeal surgery. Since their invention, laser use and applications have expanded rapidly. In this article, we discuss the benefits and disadvantages of lasers for different procedures, as well as ways to overcome commonly faced clinical problems. The use of lasers in surgery has offered a time- and cost-efficient alternative to cold surgical techniques, and has been used in the treatment of numerous laryngeal pathologies, including stenoses, recurrent respiratory papillomatosis, leukoplakia, nodules, malignant laryngeal disease, and polypoid degeneration (Reinke's edema). However, lasers can incur adjacent tissue damage and vocal fold scarring. These problems can be minimized through understanding the mechanisms by which lasers function and correctly manipulating the parameters under a surgeon's control. By varying fluence, power density, and pulsation, tissue damage can be decreased and lasers can be used with greater confidence. The various types of lasers and their applications to the treatment of specific pathologies are reviewed with the intention of helping surgeons select the best tool for a given procedure. Recent applications of lasers to treat benign laryngeal lesions and severe laryngomalacia demonstrate that additional research must be conducted to realize the full potential of this surgical tool.