Use of the Nd:YAG laser in otorhinolaryngology]

The Nd:YAG laser is suitable for the treatment of various otorhinolaryngological clinical disorders. These include the palliative reduction of tumor size in sites with difficult access, treatment of hemangiomas and reduction of hyperplastic turbinates. Within certain limits, other indications are treatment of recurrent epistaxis and recurrent polyposis. Palliative reduction of malignancies in the nasopharynx, esophagus, and bronchial system (laser power density: 1500-8000 W/cm2) must sometimes be carried out in several sessions in order to avoid complications due to the laser (i.e., perforation of the bronchial or esophageal wall, lesions of adjacent vessels or nerves). Nd:YAG laser treatment of hemangiomas (500-3000 W/cm2) can lead to excellent results. To avoid excessive thermal lesions, vascular tissue is cooled with ice cubes or with an ice-cold Ringer's solution. The laser process is continued until the onset of tissue blanching. Carbonizations of the tissue are to be avoided. In Nd:YAG laser therapy of hyperplastic lower nasal conchae (approx. 1000 W/cm2), results are based on submucous scarring in which the covering epithelium is maintained. The objective of Nd:YAG laser treatment of recurrent epistaxis in patients with Osler's disease (500 W/cm2) is to reduce the incidence of hemorrhage. Use of the laser in recurrent polyposis is best confined to patients who refuse conventional surgical revision operations. Laser light (500-3500 W/cm2) should only be applied for a short period of time (0.5 s) to avoid creating a rarefying osteitis.     

Usefulness of ND:YAG laser in head and neck surgery

Nd:YAG laser is widely used in surgery as well as in otolaryngology and head and neck surgery for 25 years. This type of laser is characterized by low absorption in water and haemoglobin, deep penetration to the tissue and high ability for vessels coagulation. The laser light can be guided with glassfiber and can be focussed with handpices and micromanipulators. These characteristics make Nd:YAG laser very useful surgical instrument, especially in ORL and head and neck surgery. One institution's experiences, based on 300 operations with Nd:YAG laser are presented and discussed. Main indications to Nd:YAG laser operations in our material were: malignant neoplasms of oral cavity, pharynx and larynx, papillomas and haemangiomas of mucosa of upper respiratory tract, tracheal stenoses, scars of the larynx after partial laryngectomies and snoring and sleep apnoea syndrome. In our opinion, Nd:YAG laser has high usefulness in treatment of malignant and benign head and neck neoplasms, as well as in laryngeal scars and treatment of snoring. In cases of post intubation tracheal stenoses and in cases of post strumectomy bilateral paralysis of larynx the treatment results were not satisfactory. High usefulness of Nd:YAG laser results from very good coagulation ability and wide possibility of transmission of laser light with glassfiber.     

Skin approximation using Nd: YAG laser in head and neck surgery

Laser is useful for surgery to cut, coagulate, vaporize and weld the tissue. Recently, low power laser was utilized for the treatment of ulcer, pain and vascular anastomosis. We applied low power Nd: YAG laser irradiation for skin approximation. An experimental study was carried out by using the Nd: YAG laser in approximating the surgically cut skin wound of guinea pigs. Healing of the wound was observed on post operative days of 3, 7 and 21, respectively. Laser approximation for the incised skin showed less scaring and faster healing than conventional suture technique. This laser technique will be beneficial as one of the new procedures of skin suture in clinical practice. The results were discussed from either technical or cosmetic standpoint.     

Interstitial Nd:YAG laser therapy. Color-Doppler imaging (CDI)-guided laser therapy of hemangiomas and vascular malformations

BACKGROUND AND OBJECTIVE: Ultrasound-(US-) guided Nd:YAG laser therapy has been reported to be promising among different other options for treatment of hemangiomas and vascular malformations.The concept of CDI-guided interstitial laser therapy is therefore a further development based on the above mentioned therapeutic regime. PATIENTS AND METHODS: We examined 55 patients suffering from vascular lesions of different localization and extent pre-, intra-, and post-operatively using color-Doppler imaging (CDI). All vascular lesions were classified due to their vascularization pattern.As accurate diagnosis was imperative we decided on possible laser treatment depending on the CDI-classification. RESULTS: Intra-operative use of CDI rendered possible fiber-guidance by sonographic navigation and therefore precise treatment of aberrant vessels and well-perfused tumor areas. In 34 cases (62%) we observed complete, in 21 cases (38%) partial regression of vascular lesions. CDI allowed post-operative proof of diminution of tumor vascularization in all cases. CONCLUSIONS: CDI-guided interstitial Nd:YAG laser therapy is a minimally-invasive technique which allows replacement of conventional surgical procedures while achieving good cosmetic and functional results.CDI broadens the therapeutic possibilities in contrast to the former therapeutic concept of US-guided laser therapy due to pre-, intra and post-operative utilization of this imaging technique while significantly diminishing the intra-operative risk for the patient.     

Nd: YAG laser treatment for adult hypopharyngeal haemangioma

Adult hypopharyngeal haemangioma is an uncommon neoplasm. We present three cases of adult hypopharyngeal haemangioma which were successfully treated with a neodymium: yttrium-aluminium-garnet (Nd: YAG) laser in our hospital between 2000 and 2003. The patients in this series experienced no untoward events from the use of the laser. Excessive bleeding and airway problems were not encountered. Postoperative pain was minimal. Excellent long-term function and a full resolution of symptoms can be obtained using Nd: YAG laser. The laser provides a bloodless field and complete healing of the hypopharynx, without stenosis or scar formation.     

Ultrasound-Guided Interstitial Nd: YAG Laser Treatment of Voluminous Hemangiomas and Vascular Malformations in 92 Patients

In many cases voluminous vascular anomalies of the head and neck region are still treated with conventional surgery, although neodymium:yttrium-aluminum-garnet (Nd:YAG) laser therapy offers a valuable treatment alternative. Ninety-two patients with voluminous hemangiomas and vascular malformations were treated with interstitial Nd:YAG laser therapy (power density, 1300 to 3300 W/cm²), partly complemented by a noncontact-mode Nd:YAG laser light application (energy density, 1000 to 2500 J/cm²). The vascular tumors had a diameter of more than 3 cm in at least two dimensions. Treatment was carried out under ultrasound and manual control. Nearly 60% of the patients (n = 55) showed a complete clinical regression. Thirty-three patients (35.8%) had a partial regression and were satisfied with the treatment outcome. Four patients were treated unsuccessfully with the laser, and three of them subsequently underwent conventional surgery. Only nine of the 92 patients (9.8%) showed cosmetic or functional impairments. The results of this first consecutive series study with a retrospective clinical evaluation of the interstitial Nd:YAG laser therapy of voluminous hemangiomas and vascular malformations in a large patient group demonstrate a high effectiveness of this novel therapy modality.     

Nd：YAG激光对兔咽部黏膜热损伤的研究

目的探讨NdYAG激光功率密度与黏膜组织热损伤程度的关系，以及激光照射后黏膜组织愈合的过程。方法激光功率密度221W／cm     

Histological changes in elastic components of soft palate scars after CO2 and contact Nd:YAG laser incisions in the dog as an experimental model

Soft palate stiffening operations — often with CO₂ or contact Nd:YAG lasers — have been used recently to treat patients with pronounced snoring. Differences in soft palate scars formed after CO₂ and contact Nd:YAG laser incisions were studied in an animal model to determine which of these lasers produces a more rigid scar and consequently might be more effective for a soft palate stiffening operation. Six mongrel dogs were placed in each laser group, after which either the CO₂ or Nd:YAG laser was used to make a 1.5-cm-long soft palate incision. The scars produced were then excised and studied histologically 4 weeks postoperatively. Special attention was paid to collagen density and elastin fibers in the scar tissue. After contact Nd:YAG laser incisions scar tissue was found to contain densely aligned collagen fibers and practically no elastin fibers. CO₂ laser incisions produced significantly different scars: irregularly arranged collagen fibers with some elastin fibers also inside the scar tissue. Differences in the shapes of the scars and wound contractions were also found that were only seen after contact laser incisions. These findings suggest that the contact Nd:YAG laser might be more effective for soft palate stiffening operations.     

Tracheal granulation tissue after percutaneous tracheostomy treated with Nd:Yag laser: three cases

Three adult patients who received percutaneous serial dilatational tracheostomy post-cardiac surgery developed histologically confirmed tracheal granulation tissue superior to the point of entry of the tracheostomy tube into the trachea. This tissue significantly occluded the trachea in all patients and, in two, led to serious haemorrhage. Each patient had serial dilatational percutaneous tracheostomy using the Cook/Ciaglia technique. On each patient fibre-optic bronchoscopy confirmed satisfactory position of the guidewire and tracheostomy tube. Nd:Yag laser therapy was applied to areas of tracheal granulation tissue and was also employed to secure haemostasis. In each patient endobronchial Nd:YAG laser therapy successfully cleared the granulation tissue and secured haemostasis. Follow-up bronchoscopy showed no recurrence. Fibre-optic bronchoscopy at the time of tracheal decannulation may identify granulation tissue requiring appropriate referral and intervention.     

Indikationen zur prim?ren operativen Therapie von Gef??anomalien im S?uglingsalter

LASER THERAPY: Since the introduction of laser therapy for treatment of hemangiomas and vascular malformations, primary surgical therapy has gradually lost importance. Particularly hemangiomas, but also venous malformations and lymphangiomas, are nowadays primarily treated by different types of lasers. Especially the Nd:YAG laser with a percutaneous or transcutaneous application technique often leads to satisfying results. SURGICAL THERAPY: Surgical therapy is mostly used secondarily in late childhood or in adults after several laser applications for excision of residual scars or other corrective procedures. Despite these improvements in laser therapy, there is still an indication for primary surgical treatment in subcutaneous vascular malformations and in rapidly growing hemangiomas after unsuccessful laser therapy. Even in large vascular anomalies, safe excision with only a little blood loss is possible if the tumors are encapsulated. CASE REPORTS: In this paper we want to point out the necessity of primary surgery in three children in whom complications such as loss of sight, facial nerve palsy, and a lethal outcome due to massive hemorrhage in a cystic lymphangioma could be avoided.     

Dose-related tissue effects of the CO2 and noncontact Nd:YAG lasers in the canine glottis

Objectives: The CO₂ laser is the standard for control of recurrent respiratory papillomatosis because of its predictable action on laryngeal tissue. The noncontact neodymium:yttrium aluminum garnet (Nd:YAG) 1064-nm laser is generally not used in the larynx owing to the lack of data on its tissue effects, and its potential lack of safety in the larynx. Combined Nd:YAG and CO₂ laser treatments have been used safely in the tracheobronchial tree to eradicate recurrent respiratory papillomas. The objectives of this study were to describe and evaluate a method for applying the noncontact Nd:YAG laser to the larynx, to compare the tissue effects of the Nd:YAG, CO₂, and combined Nd:YAG and CO₂ lasers in the canine larynx, and to extrapolate canine tissue data to the human. Methods: The CO₂, Nd:YAG, and combined Nd:YAG/CO₂ lasers were applied to the glottis in four mongrel dogs. Laryngectomy was performed and the tissue was examined histologically. The nature and degree of tissue injury were analyzed relative to laser type and energy data. Results: In the canine larynx, the CO₂ laser vaporized the surface epithelium and caused varying degrees of edema and necrosis of the lamina propria. The Nd:YAG laser did not cause ulceration but did show a greater degree of thermal damage to the lamina propria. Combined Nd:YAG/CO₂ applications resulted in separation of the perimysial fibers from the muscle fibers of the vocalis muscle. Conclusion: These findings suggest that the noncontact Nd:YAG laser can be applied in a controlled fashion to the canine larynx at appropriate power densities. Anatomical differences between human and canine larynges are considered. Extrapolation to humans is proposed. Key Words: Laser, larynx, tissue effects, papillomatosis.     

Nd:YAG激光与射频治疗鼻腔利特尔区出血的疗效比较

目的比较Nd:YAG激光与射频治疗鼻腔利特尔区出血的效果.方法576例鼻出血患者,Nd:YAG激光治疗390例,射频治疗186例,随访时间6～12个月.结果两组的治愈率分别是77.4%和95.2%(P＜0.05);治疗后需鼻腔填塞的比例分别是44.4%和12.9%(P＜0.05);需再次治疗比例分别是15.8%和6.5%(P＜0.05).两种治疗方法差异有显著性意义.结论在鼻出血治疗中,射频更方便有效.     

Combined intratumor cisplatinum injection and Nd:YAG laser therapy

OBJECTIVES/HYPOTHESIS: Interstitial laser therapy (ILT) has become useful for tumor palliation in patients with advanced head and neck cancer. Cisplatinum chemotherapy also is a frequent adjuvant treatment for recurrent tumors, but systemic toxicity limits application. Intratumor cisplatinum injection combined with ILT may improve therapy of these recurrent tumors with reduced toxicity. STUDY DESIGN: Prospective. Tumor transplants were injected with cisplatinum in a gel implant before ILT to evaluate treatment response and toxicity in a preclinical study. METHODS: UCLA-P3 human squamous cell carcinoma tumors were grown as subcutaneous transplants in nude mice and treated by intratumor injection of 2 mg/mL cisplatinum in a slow-release, collagen-based gel carrier 4 hours before interstitial implantation of Nd:YAG laser fiberoptics to induce local tumor hyperthermia. Treatment efficacy and toxicity were followed for 12 weeks after combined drug and laser therapy compared with ILT alone. RESULTS: Combined cisplatinum gel and ILT was a significant improvement (P < .01 by chi-square test) and induced 57% complete responses without regrowth in 21 transplanted tumors compared with only 24% in 21 tumors after ILT alone during 12-week follow-up. Recurrences in both cases appeared to result from nonuniform laser energy delivery within tumors via the implanted fiberoptic tip. CONCLUSIONS: The results of this experimental combined cisplatinum and ILT study suggest it may be possible to improve treatment of advanced head and neck cancer by intratumor injection of gel implants containing the drug followed by interstitial Nd:YAG laser hyperthermia.     

Bioinhibition of human fibroblast cultures sensitized to Q-switch II dye and treated with the Nd: YAG laser: a new technique of photodynamic therapy with lasers

Kodak Q-switch II dye has recently proven to be an effective biostimulative agent on normal human fibroblast cultures. The potential for this dye as a new chemosensitizing agent for the treatment of connective tissue diseases and wound healing with the Nd:YAG laser was examined. Two normal fibroblast cell lines were first sensitized to a nontoxic dose of Q-switch II dye, then subjected to treatment with an Nd:YAG laser at 1,060 nm, with varying levels of energy and temperatures determined by a reproducible method of dosimetry. The results indicate that Q-switch II dye at nontoxic doses of 0.1 micrograms/ml enhances the cytotoxic effects of the Nd:YAG laser at temperatures as low as 36 degrees C. Furthermore, at physiological temperature ranges as low as 24 degrees C to 34 degrees C, cell duplication was inhibited, but cell viability was not affected. Similar results were not observed when fibroblast cultures were treated with the laser alone. These observations suggest that Q-switch II dye is an effective chemosensitizing agent for the Nd:YAG laser and could potentially be used to reduce collagen deposits in conditions such as keloids and hypertrophic scars.     

鼻咽癌局部复发或残留病灶的Nd：YAG激光手术挽救治疗

目的 探讨Nd:YAG激光手术挽救治疗鼻咽癌放射治疗后鼻咽局部复发或残留的可行性和临床疗效。方法在鼻内镜下经鼻腔Nd:YAG激光,对35例鼻咽癌经根治性放射治疗后鼻咽局部复发或残留病灶进行治疗。手术在局麻下进行,在鼻内镜直视下,激光功率调整在50W左右,YAG激光光纤经同侧或对侧鼻腔导入鼻咽部,气化切除肿瘤病灶。部分患者术后接受了再放射治疗,放射剂量20-60Gy不等。结果 手术均顺利完成。术后3年、5年生存率分别为51.4%、30.3%。结论 鼻内镜下Nd:YAG激光挽救手术是治疗鼻咽癌放射治疗后鼻咽局部复发或残留的有效手段,丰富了鼻咽癌放射治疗失败后的外科治疗手段。术后是否再需放射治疗,视具体情况决定。     

Nd:YAG laser treatment of the lower turbinates with contact in hyperreflexic and allergic rhinopathy]

BACKGROUND: Nasal obstruction caused by mucosal swelling due to hyperreflectory or allergic rhinitis is a very frequent disorder. We would like to report about our first results (ENT department, University of G?ttingen) in the reduction of hyperplastic inferior turbinates by Nd:YAG Laser treatment. PATIENTS AND METHOD: One hundred seventeen patients with nasal obstruction were treated by Nd:YAG laser between October 1993 and February 1997. We used the laser in "contact mode" and all outpatients were under local anaesthesia. Follow-up was possible in 83 cases. A subjective scale was used to evaluate our results. One quarter of the patients suffered from an allergic rhinitis. RESULTS: For 80% the nasal airflow was increased. Sixty percent had excellent or good results without any nasal obstruction after therapy. The patients with allergic rhinitis performed as well as the patients with hyperreflectory rhinopathy. This improvement appeared as early as four weeks after treatment and was permanent in 37 of 40 cases with long-term observation of at least one year. Side effects: 14% reported a dry nasal mucosa for two weeks; 31% had a bloody nasal secretion for two days after treatment, but did not bleed. Fifteen percent complained of pain during the procedure. CONCLUSION: The reduction of the inferior turbinates by Nd:YAG laser is an effective treatment of equal value in symptomatic therapy of the hyperplastic turbinates due to hyperreflectory and allergic rhinopathy. Seventy-three percent of these patients would like to be treated in this way again if necessary.     

Ultrasound-guided laser-induced thermal therapy of malignant cervical adenopathy

OBJECTIVES: Laser-induced thermal therapy (LITT) for cancer is a technique whereby a source of energy (laser, radiofrequency, ultrasonic, cryoenergy, and so on) is directly applied into a tumor at various depths. Recent studies have demonstrated the efficiency of ultrasound (UTZ) and magnetic resonance imaging (MRI) for real- or "near" real-time tumor and vessel identification as well as monitoring and quantifying energy-induced tissue damage. The objective of this study is to report UCLA's experience using UTZ monitoring of Nd:YAG laser thermal ablation of malignant cervical adenopathy in a phase II study. STUDY DESIGN: The authors conducted a retrospective study of patients treated at a tertiary medical center. METHODS: Forty-seven patients with a total of 55 neck tumors were treated on an outpatient basis in the operating room using UTZ for image-guided laser interstitial thermal therapy. Laser energy was delivered through an SLT Nd:YAG laser powered at 30 W (power density: 2,200 J/cm). RESULTS: Eleven patients had a complete response ranging from 5.5 to 90 months (mean, 22.1 months). Based on the findings of this study, it was possible to show that proximity to the carotid artery was the most relevant factor in projecting patient survival. Patients' individual treatment analysis and final outcome are further discussed. CONCLUSIONS: LITT ablation of malignant cervical adenopathy was considered safe and feasible. No intraoperative complications occurred. Further development of this technique applying laser energy delivery to mathematical imaging models should lead to more effective tumor palliation as an alternative to surgery.     

Management of epistaxis in hereditary hemorrhagic telangiectasia by Nd:YAG laser and quality of life assessment using the HR-QoL questionnaire

The purpose of this study was to describe the results of Nd:YAG laser application in hereditary hemorrhagic telangiectasia (HHT) patients and to measure the Health-Related Quality of Life (HR-QoL) in patients with HHT before and after Nd:YAG laser application in a prospective, clinical trial at a university hospital. Twenty-seven consecutive patients with HHT and mild to moderate degrees of epistaxis were followed-up for 2 years after Nd:YAG laser treatments. Recurrence of epistaxis after Nd:YAG laser application and measurement of HR-QoL using the International Quality of Life Assessment questionnaire, version 1.1 (IQOLA 1.1), was found. Eight patients (30%) received only one Nd:YAG laser treatment, 15 (56%) had a recurrence and received a second treatment and 4 (14%) had two recurrences and received three Nd:YAG laser treatments. HR-QoL was improved 2 years after the first Nd:YAG laser application in both its Physical Health Dimension (47.5±2.9 vs. 38.1±2.3 before treatment, P <0.05) and Mental Health Dimension (45.1±2.7 vs. 39.6±2.4 before treatment, P <0.05). Although no curative treatment for HHT exists, Nd:YAG laser treatment seems to constitute a simple and efficient method of epistaxis control, resulting in a significant improvement in quality of life.     

纤维喉镜下Nd:YAG激光治疗760例声带息肉和小结的疗效分析

目的 评价纤维喉镜下激光治疗声带息肉和声带小结疗效。方法 对随访2年以上的760例声带息肉（516例）和小结（224例）病人进行了总结、分析。结果 声带息肉和小结一次性治愈率分别为96％、99％，末彻底治愈的20例声带息肉病人、3例声小结病人经再次激光治疗后痊愈。结论 纤维喉镜下引导导激光是治疗声带息肉和小结的有效方法，具有痛苦小、反应轻、恢复快、复发率低的优点。     

Endotracheal and bronchial laser surgery in the treatment of malign and benign lower airway obstructions

Lower airway obstruction usually causes a remarkable reduction in the quality of life in cases of both benign and malignant tracheobronchial intraluminal tumor growth. Often this growth can also lead to premature death because of ventilation failure or, indirectly, because of fatal infections. In combination with external radiation therapy, laser surgery has become a standard means of treatment for these patients. From 1987-1999, 102 patients were treated with 270 laser treatment sessions (89 for malignant and 13 for benign diseases) at Turku University Hospital. Treatment was performed mostly with a combination of CO(2)-Nd:YAG laser via a rigid bronchoscope but also with a CO(2) laser and fiberoptic Nd:YAG laser. The treatment was considered successful in 208 cases of 270 treatment sessions (77%). The most important single factor affecting the success of the therapy was the unfavorable location of the tumor (40 cases). In these cases, the tumor was either located too distally in the bronchial tree, or the airway obstruction was found to be caused by extraluminal compression. There were two fatal complications (0.8%). Other complications affecting the quality of the procedure were minor intraoperative bleeding in 7.4% (20/270) and intraoperative ventilation problems in 7.0% (19/270). The 1-year survival of the patients with malignant disease was 37.1% (33/89), the 2-year survival 20.2% (18/89) and the 5-year survival 9.0% (8/89). Laser treatment is an effective method in maintaining tracheobronchial ventilation as a palliative treatment modality. Serious complications are possible, but considering the fatal nature of the disease, laser treatment can be recommended. In cases of benign diseases, endobronchial laser treatment was also very successful.