CO2 laser surgery of the upper airway

The use of CO2 laser surgery in otolaryngology has served as an effective tool to treat various lesions in the upper airway. This article discusses application of the CO2 laser to the upper airway, with specific reference to the larynx, nasal cavity, nasopharynx, and oropharynx.     

The CO2 laser in pediatric surgery

The CO2 laser has found its place in surgery and is now an accepted modality in many fields. Its application in pediatric surgery is well based and it is our opinion that its use in this field should be more widespread.     

The effect of CO2 laser excision on local tumor recurrence

This study was undertaken to determine the effect of CO2 laser surgery on the incidence of local recurrence following tumor recurrence and to study the effect of "sterilization" of the operative site on this phenomenon. Sixty Fisher 344 rats were implanted with R323OAC mammary carcinoma. Animals were anesthetized with intraperitoneal pentobarbital, and all tumors were completely excised at 21 days postimplantation. The animals were randomized into groups of 12 as follows: Group S underwent excision with the scalpel. Group E underwent excision with electrocautery (Bovie, Valley Labs, Boulder, CO). Group L and LV underwent excision with the Sharplan 733 CO2 laser (Laser Industries, Israel) (TEMoo, 125-mm handpiece, 25-W continuous wave). Group LV wounds were then "sterilized" by using the laser defocused to a 5-mm spot size and gently heating the site without producing blanching or charring of the tissues. Primary tumor size was 2.0 +/- 0.5 cm and was similar in all groups. Animals were observed for recurrence for 33 days postoperatively. Mortalities were excluded from analysis. Tumors recurred in 7/9 (78%) in group S, 5/11 (45%) in group E, 4/10 (40%) in group L, and only 1/12 (8%) in group LV. All results are significant at P less than 0.05. The CO2 laser is an effective surgical adjunct to reduce local tumor seeding and recurrence. This effect is enhanced by "sterilizing" the surgical site with the defocused laser beam.     

Reduction of local tumor recurrence by excision with the CO2 laser

This study was undertaken to determine the effect of CO2 laser surgery on the incidence of local recurrence following tumor resection. Thirty female Fisher 344 rats were implanted with R3230AC mammary carcinoma. All tumors were completely excised 18-21 days post-implantation. In 15 animals, the resection was done with a scalpel. Fifteen animals underwent laser excision with the Sharplan 733 CO2 laser (TEMoo, 125 mm handpiece, 25W continuous wave). Primary tumor size was 17.6 +/- 1.4 mm in the scalpel group and 21.2 +/- 6.3 mm in the laser group. Tumor recurred in 14/15 (93.4%) of the scalpel group and 5/15 (33.3%) of the laser group (p less than 0.001). The site of recurrence was incisional in 13/15 (86.7%) of the scalpel group and 3/15 (20%) of the laser group (p less than 0.001). Axillary metastases occurred in 2/15 (13.3%) in each group. The disease-free interval was 26 days in the laser group and 12 days in the scalpel group. The CO2 laser is an effective surgical adjunct to reduce local tumor seeding and recurrence.     

Carbon dioxide laser excision of benign pedal lesions.

The CO2 laser is a very important tool to remove benign pedal lesions. It certainly is not the only method, but once the technique is developed by the surgeon, it becomes easier to remove these lesions and, consequently, the results become better. In dealing with the mucoid cysts, the laser surgery is second to none and even if it has to be repeated there is basically no disability for the patient. This is also true with fibromas because many types of fibromas would require suturing that would create an inconvenience for the patient. With the use of the laser, sutures are not required and the patients recover much faster. In dealing with plantar fibromatosis, ganglionic cysts, and lipomas, the convalescence is probably about the same with CO2 laser as with conventional removal, especially when deep resection is necessary and suturing of the skin is required. With plantar fibromata surgery, the resultant long-term scarring is much less with the CO2 laser, especially when followed up with the appropriate injectables. CO2 laser surgery performed on the punctata aeriata, interdigital clavus formations, and hypertrophic scars are not always as successful but offer the surgeon another modality in taking care of the patient's problems without the need for extensive surgery.     

CO2 laser therapy in malignant and premalignant lesions of the larynx

Twenty-nine patients have undergone CO₂ laser surgery for dysplasia or for malignant disease of the larynx. Nine patients treated for dysplasia show no signs of recurrence and, of 20 patients treated for malignant disease of the larynx, 14 are currently alive. From these results it is possible to define the indications for laser surgery and to show that there may be advantages in combining laser surgery with other forms of treatment for malignant disease.     

Palliation of airway obstruction from tracheobronchial malignancy: use of the CO2 laser bronchoscope

A CO2 laser rigid bronchoscope system has been used to palliate symptoms of a malignancy obstructing the tracheobronchial airway. Fifty-nine endoscopic laser operations (34 patients) were done between 1975 and 1981. Severe dyspnea and obstructive atelectasis were the most common indications for treatment. Contraindications for treatment included extrinsic tracheobronchial compression, widespread distant metastases, rapidly progressing tumors, and highly vascular neoplasms. There were nine primary tracheal malignancies, five metastases from distant sites, and 20 primary lung cancers with tracheobronchial obstructions. Most patients were previously treated with one or more standard modalities (radiation therapy, surgery, and chemotherapy). Removal of airway obstruction was occasionally indicated prior to radiation therapy to facilitate treatment. There were seven instances of complications in this group of patients and one mortality. Most patients (23 of 34) have died from their malignancy. The best palliation was achieved in proximal (tracheal and main stem bronchial), slower growing tumors.     

The effect of fractional CO2 laser irradiation on remineralization of enamel white spot lesions

This study investigated the combined effect of fractional CO₂ laser irradiation and fluoride on treatment of enamel caries. Sixty intact premolars were randomly assigned into four groups and then stored in a demineralizing solution to induce white spot lesions. Tooth color was determined at baseline (T1) and after demineralization (T2). Afterwards, the teeth in group 1 remained untreated (control), while group 2 was exposed to an acidulated phosphate fluoride (APF) gel for 4 min. In groups 3 and 4, a fractional CO₂ laser was applied (10 mJ, 200 Hz, 10 s) either before (group 3) or through (group 4) the APF gel. The teeth were then immersed in artificial saliva for 90 days while subjected to daily fluoride mouthrinse and weekly brushing. Color examinations were repeated after topical fluoride application (T3) and 90 days later (T4). Finally, the teeth were sectioned, and microhardness was measured at the enamel surface and at 30 and 60 μ from the surface. In both lased groups, the color change between T1 and T4 stages (?E _T1–T4) was significantly lower than those of the other groups (p?<?0.05). Laser irradiation followed by fluoride application (group 3) caused a significant increase in surface microhardness compared to APF alone and control groups (p?<?0.05). Microhardness at depths of 30 and 60 μ was also significantly greater in group 3 compared to those of all other groups (p?<?0.05). Application of a fractional CO₂ laser before fluoride therapy is suggested for recovering the color and rehardening of demineralized enamel.     

Comparison of local tumor recurrence following excision with the CO2 laser, Nd:YAG laser, and Argon Beam Coagulator

This study compares the incidence of local tumor recurrence following primary excision with the CO2 laser, Nd:YAG laser (contact), Argon Beam Coagulator, or electrocautery. One hundred eight Fisher 344 rats with R3230AC mammary tumors (1.6 +/- 0.04 [SD] cm diameter) were used. All animals were randomized into groups of similar tumor size. In groups C and CS, excision was performed with a Sharplan 1060 CO2 laser (TEMoo, 25 W, continuous wave [CW], 0.2-mm spot size). Wounds in group CS were "sterilized" (0.5-mm spot size, 25 W, CW) by gently heating the wound without causing blanching or charring. In group N, a 0.4-mm contact Laser Blade and a Cooper 8000 Nd:YAG laser at 20 W CW was used. In groups SA1 and SA2, tumors were excised with the scalpel, and hemostasis and wound "sterilization" were accomplished with the Bard System 6000 Argon Beam Coagulator (ABC) at 40 W and 4 liters/min argon gas flow in SA1 and 12 liters/min in SA2. In group E, excision was accomplished at 40 W blend mode, 10 W spray mode. In group EA, excision was accomplished at 60 W cutting current, and hemostasis was achieved with the ABC. The animals were examined for evidence of recurrence for 34 days postoperatively. Mortalities were excluded from analysis. The incidence of recurrence was 11/14 (79%) in C, 6/16 (38%) in CS, 10/14 (71%) in SA1, 6/13 (46%) in SA2, 6/15 (40%) in N, 7/10 (70%) in EA, and 3/15 (20%) in E. Group E is statistically different (P less than .01) from groups EA, C, and SA1. Group C was different (P less than .01) from groups E, CS, and N. These results demonstrate an inverse relationship between tumor recurrence and local thermal effects at the surgical site. The ABC did not increase tumor recurrence. Contact YAG surgery was similar to CO2 laser excision and "sterilization." An attempt to study the influence of gas flow and pressure on local tumor recurrence and metastases should be made.     

The use of the carbon dioxide laser in the pediatric airway.

Congenital and acquired lesions of the pediatric airway present difficulties in management. Until recently, correction of these problems frequently involved an external approach to the larynx and trachea. Development of fiberoptic instrumentation, as well as the introduction of the Zeiss operating microscope, has now given the surgeon a new means to visualize the larynx and trachea. Soon after its development, the carbon dioxide surgical laser was coupled to these instruments to permit an extremely precise form of tissue excision and ablation. Its unique properties, including an extraordinary hemostatic effect, as well as minimal postoperative edema and scarring, make it an ideal tool for management of lesions of the pediatric airway. It has been employed successfully in the treatment of 177 lesions.     

Endoscopic Nd-YAG laser treatment and adjuvant therapy of metastatic lesions of airway

Endoscopic Nd-YAG laser treatment and adjuvant therapy were performed in 44 cases with metastatic lesions of airway. The best results were obtained in 31 cases (93.9%) out of 33 cases complaining of ventilatory disturbance in which endoscopic Nd-YAG laser treatment was indicated as an emergency procedure. In most of these cases with metastatic lesions of airway consisted of respiratory tract invasion from mediastinal lymph nodes in cases of esophageal cancer or lung cancer. In these cases, after laser treatment for ventilatory disturbance, the patients condition improved to the extent that adjuvant therapy could be performed. Adjuvant therapy was performed in 38 cases, there were 7 cases treated surgically (resection of the metastatic lesions of airway in 3 cases, tracheal tube stent operation in 4 cases 0, 28 radiotherapy in 28 cases (Linac irradiation in 24 cases, 60Co intraluminal irradiation of the trachea in 4 cases 0, and 32 cases were treated with chemotherapy. Tracheal tube stent operation was useful for maintenance of the tracheal lumen following laser treatment, and 60Co intraluminal irradiation was effective for the residual intratracheal tumor. The 1-year survival rate of 44 cases with metastatic lesions of airway was 42% and the 2-year survival rate was 22%, so this result suggested endoscopic Nd-YAG laser treatment and adjuvant therapy for metastatic lesions of airway was useful to prolong survival time. However the main value of this modality is for the rapid relief of severe ventilatory disturbance due to obstructive airway lesions.     

Vulvar lesions classification and critical study of the indications of laser CO2 in 51 cases

The treatment of vulvar lesions entails practical and theoretical knowledge of their anatomy, natural history and classification. The hormonal status and the affinity of the HPV virus for the vulvar region have therapeutic implications and must be taken into consideration. The introduction in 1984 of CO₂ laser therapy at the Claudius Regaud Cancer Center, has allowed us to have two groups of cases. One group consists of 36 patients treated by classical techniques (electrocoagulation, local resection, vulvectomy), and a second group of 51 patients, treated by vaporization or excision with laser beam. In this second group, the percentage of recurrences of condylomas is low (1/25). The percentage of recurrences of dysplasia and of intra-epithelial malignancies is not insignificant but is not different from that of conventional treatment; electrocoagulation or surgical resection, 4/12 and with laser vaporization, 3/11. However, the infiltrating lesions, which represent a small number of the series, recur less frequently after vulvectomy with laser (0/7 cases) than after classical total vulvectomy (3/20 cases).Nevertheless, the advantage of the CO₂ laser is not in this area. The indications for this type of therapy are primarily for the treatment of viral induced lesions. On the other hand, laser therapy is well adapted to the treatment of dysplasia, when used in conjunction with the microscope. Laser therapy allows a very good outline of the lesions and their depth of the lesions and of the homogeneity of the vaporization. This form of therapy is used like an optical knife, in particular for performing a superficial total vulvectomy. The post-operative period for the patients is quite comfortable and with decreased morbidity.

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Résumé Le traitement des lésions vulvaires impose la connaissance théorique et pratique de la classification de ces lésions. Le statut hormonal et le tropisme des HPV virus pour la région vulvaire méritent d'être soulignés étant données leurs implications thérapeutiques. L'introduction en 1984 du laser CO₂ dans le cadre d'un Centre Anticancéreux, a permis la définition de deux séries: une première de 36 patientes traitées par moyens classiques (électrocoagulation, résections, vulvectomies) et une seconde de 51 cas traitées par vaporisation ou excision-laser. Dans cette dernière, le taux de récidives des condylomes est faible (1/25). Le taux des récidives des dysplasies et des épithéliomas intraépithéliaux n'est pas négligeable, mais n'apparait pas différent selon que le traitement en ait été conventionnel (électrocoagulation, résection chírurgicale) (4/12) ou réalisé par vaporisation laser (3/11). Les lésions infiltrantes, au faible nombre de la série près, semblent récidiver moins fréquemment après vulvectomie réalisée au laser (0/7 cas), qu'après vulvectomie totale classique (3/20 cas).L'avantage du laser CO₂ ne se situe cependant pas à ce niveau. Ses indications sont évidentes vis à vis du traitement des lésions viro-induites. Il est par ailleurs bien adapté au traitement des dysplasies, son utilisation couplée au microscope permettant une bonne délimitation des lésions et une profondeur homogène de vaporisation. Utilisé comme bistouri optique et en particulier pour la réalisation de la vulvectomie totale superficielle, il apporte enfin un bénéfice pour les patientes en terme de confort post-opératoire et de réduction de la morbidité.

     

Precision resection of intra-axial CNS lesions by CT-based stereotactic craniotomy and computer monitored CO2 laser

Summary This report describes an open stereotactic technique by which a tumour volume reconstructed in stereotactic space from CT data is removed by stereotactic CO₂ laser vaporization. The position of the laser beam in relation to the tumour outlines is monitored by computer and displayed to the surgeon on a graphics display terminal in the operating room. Twenty-six (26) of these procedures have been performed on twenty-four (24) patients with deep-seated intraaxial neoplasms (23) and arteriovenous malformation (1). Post-operative CT scanning revealed no evidence of contrast enhancing lesions in nineteen (19) patients while a small amount of residual tumour was noted in five (5) patients post-operatively. This method has proven itself valuable for maintaining three-dimensional surgical orientation for the resection of intra-axial neoplasms from neurologically important areas.     

Experimental CO2 laser myringotomy.

OBJECTIVE: The purpose of this study was to compare closure rates of CO2 laser myringotomies with those produced conventionally with a knife. STUDY DESIGN AND SETTING: We investigated closure rates in 3 experimental groups of chinchillas: (1) semicircular myringotomy in both ears either produced with a knife or CO2 laser; (2) CO2 laser myringotomy, round in one ear and kidney shaped in the other; (3) CO2 laser myringotomy, incisional in one ear and kidney shaped in the other. RESULTS: Patency of knife myringotomies was shorter (P < 0.01) than of similar laser myringotomies, means 10.0 and 21.8 days, respectively. The patency of kidney-shaped laser myringotomies was longer (P < 0.05) than of round ones. Incisional laser myringotomies remained open longer (P < 0.01) than round ones. CONCLUSION: Use of CO2 laser as well as certain geometries delay the closure of myringotomies. By allowing perforations of different shapes and sizes, CO2 laser myringotomy may become an alternative in the treatment of otitis media.     

Hysteroscope for CO2 laser application

Endoscopic laser surgery is becoming more common with the development of suitable instruments. A hysteroscope designed for use with a Sharplan CO₂ laser is described in detail. The method of application, results of preliminary experience, and possible indications are discussed.