Intralesional cidofovir for recurrent respiratory papillomatosis in children.

OBJECTIVE: To assess the potential benefit of intralesional administration of cidofovir, an acyclic nucleoside phosphonate with activity against several DNA viruses, for treating severe respiratory papillomas in pediatric patients. DESIGN: Prospective case series. SETTING: Tertiary care children's hospitals. PATIENTS: Five pediatric patients with severe recurrent respiratory papillomatosis requiring laryngoscopy with carbon dioxide laser therapy more frequently than once a month to maintain airway patency. Each patient underwent between 12 and 33 laryngoscopies with laser treatment prior to being injected with cidofovir. INTERVENTION: Microsuspension laryngoscopy with intralesional injection of cidofovir (Vistide) in conjunction with mechanical debulking and carbon dioxide laser of papillomas. MAIN OUTCOME MEASURE: Papilloma stage at time of serial laryngoscopies. RESULTS: One patient was disease free and 3 patients demonstrated a dramatic response to adjuvant therapy with cidofovir at the 9-month follow-up visit after the last injection of cidofovir. One patient showed an improvement in papilloma stage that was possibly related to concurrent therapy with interferon. CONCLUSIONS: Intralesional injection of cidofovir seems to be of benefit in the treatment of severe respiratory papillomatosis in pediatric patients. Larger prospective studies with longer follow-up will be required before cidofovir can be considered an accepted means of managing this difficult disease.     

Surgical lasers and soft tissue interactions

The different physical and biological qualities of the carbon dioxide, argon, and neodymium-YAG lasers provide the otolaryngologist and head and neck surgeon with a surgical tool with specific qualities and applications. The specific wave lengths of laser energy produce a varied soft tissue action. The carbon dioxide laser energy is absorbed by all biological tissues, whereas argon laser energy is an effective photocoagulator and penetrates into the subepithelial plane; the Nd-YAG laser creates a coagulation effect, which penetrates deep into the tissues. Each laser has specific physical qualities. The argon laser and the Nd-YAG laser can be transmitted through a flexible fiberoptic delivery system, whereas the carbon dioxide laser currently requires a rigid optical delivery system. The Nd-YAG and carbon dioxide lasers both require a second coincident aiming beam because of the invisibility of their laser energy, whereas the argon laser does not have such a requirement. The spot size of the laser beam can be much smaller for the argon laser than for the carbon dioxide laser. Protective lenses are necessary for the argon, carbon dioxide, and Nd-YAG lasers. The carbon dioxide laser energy is not transmitted through glass; thus most media (glass, plastic) are suitable to prevent any ocular injury. The argon laser requires a special yellowish protective mechanism, and the Nd-YAG laser requires a green protective lens mechanism. With further technical advances and improvements in the fiberoptic delivery system, smaller laser spot sizes, and changes in operating laser modes and color specifications of lasers, the advantages of laser surgery over conventional surgical techniques will become increasingly more apparent.     

Laser surgery of the vocal cords. An experimental study with carbon dioxide lasers on dogs

In experiments on dogs, a focused beam from a continuous wave surgical carbon dioxide laser integrated with an operating microscope was used selectively to evaporate predetermined amounts of normal vocal cord tissue through a laryngoscope. This mode of tissue removal was precise, rapid and practically bloodless. Microscopic laryngoscopy examinations and histological work-up one, two and three weeks postoperatively indicated normal healing similar to that of clean surgical wounds.     

Powered instrumentation in the treatment of recurrent respiratory papillomatosis: an alternative to the carbon dioxide laser

OBJECTIVE: To assess the advantages of powered instrumentation vs the carbon dioxide laser in treating patients with juvenile-onset recurrent respiratory papillomatosis. DESIGN: A retrospective study. SETTING: Tertiary care children's hospital. PATIENTS: Patients operated on for juvenile-onset recurrent respiratory papillomatosis between January 1, 1999, and December 31, 2000. Papillomas were excised using the microdebrider in one group and the carbon dioxide laser in the second group. INTERVENTIONS: Direct laryngoscopy and bronchoscopy, suspension microlaryngoscopy, and excision of papillomas by the carbon dioxide laser or the microdebrider. MAIN OUTCOME MEASURES: Operative time and postoperative complications. RESULTS: Seventy-three operations were performed (23 with the laser and 50 with the microdebrider). Sixteen patients were included, 10 with active disease and 5 with disease in remission; 1 was lost to follow-up. They had a mean age of 3.75 years, and the male-female ratio was 7:9. The patients presented mostly with hoarseness (13 [81%]). Four (25%) had soft tissue complications with the laser. The microdebrider was less time-consuming than the laser, although those treated with the microdebrider had more active disease. No factor could be used to measure treatment outcome due to disease variability. Those who were older, female, and African American tended to have less severe manifestations of disease. CONCLUSIONS: The microdebrider proved to be less time-consuming than the carbon dioxide laser when used in patients with juvenile-onset recurrent respiratory papillomatosis. Soft tissue complications were nonexistent. In addition to safety, the microdebrider is more appealing to the surgeon, anesthesiologist, and parents, especially because these children often need subsequent surgical procedures.     

声门上区喉淀粉样变3例并文献复习

目的 探讨临床上易误诊为恶性肿瘤的声门上区喉淀粉样变的临床特点及诊治措施.方法 对3例声门上区喉淀粉样变患者行喉显微镜下CO₂激光辅助喉部病变切除术,并对临床资料进行分析.结果 3例患者均经喉显微镜CO₂激光手术治愈,术后随访1~2年,未复发.结论 喉淀粉样变临床表现缺乏特异性,但病理切片刚果红染色阳性可确诊本病;喉显微镜CO₂激光手术是有效的喉淀粉样变治疗手段.     

Graded carbon dioxide laser-induced subglottic injury in the rabbit model

OBJECTIVE: To conduct an endoscopic and histologic analysis of the subglottic effects of various carbon dioxide laser-induced injuries in the rabbit model. DESIGN: Animals were assigned to either a control (cricothyroidotomy only) group or 4 (cricothyroidotomy and posterior subglottic laser) groups that were injured using varying systematically controlled carbon dioxide laser power exposures (5 W, 8 W, and 12 W), with durations of 2 or 4 seconds, and surface area exposures (25% or 40%). SUBJECTS: Twenty-seven New Zealand white rabbits. INTERVENTIONS: The subglottis was approached via cricothyroidotomy. Control airways were immediately closed, while injured airways were subjected to graded carbon dioxide laser exposures prior to closure. Airways were endoscopically monitored preoperatively, immediately postoperatively, and on postoperative days 1, 7, 14, and 21, after which the animals were humanely killed and subglottic tissue harvested for histological evaluation. RESULTS: Clinical observation revealed no significantly obstructive (acute) stenosis during the duration of the study. Endoscopic visualization revealed the formation of posterior subglottic scarring. Histological analysis of the mucosa revealed that use of carbon dioxide laser resulted in a statistically significant (unpaired, 2-tailed t test, P<.05) proportional thickening of the lamina propria layer, without significant changes in the epithelial and cartilaginous layers. In addition, mucosal blood vessel size increased proportional to the power of the laser delivered to the area (P<.05). CONCLUSIONS: Carbon dioxide laser-induced injury to the subglottis caused localized scarring, lamina propria thickening, and increased vascularity, which resolved with time and was not associated with significant airway obstruction. This model describes a systematic, controlled, and reproducible method of investigating subglottic injury.     

The effect of blood on laser-resistant endotracheal tube combustion

The protection afforded against CO₂ laser-induced combustion by five different types of tracheal tubes or protective foil wraps was evaluated. They were compared before and after the application of human blood to their external surfaces. The tracheal tubes tested were polyvinylchloride (PVC) tubes wrapped with Venture^TM copper (Cu) foil tape, 3M^TM aluminum (A1) foil tape, and the Laser-Guard^TM protective coating. The Xomed Laser Shield IF^TM and Mallinckrodt Laser-Flex^TM tracheal tubes were also tested. A CO₂ laser set to 38 W in the continuous mode was directed at the shaft of the tracheal tube under study, which had 5 L/min of oxygen flowing through it. The laser was actuated for 90 seconds or until combustion or melting occurred. The copper foil-wrapped and aluminum foil-wrapped PVC tracheal tubes were unaffected by 90 seconds of laser fire in five trials with each type of tape. However, the application of blood to the foil wrapped PVC tracheal tube shafts resulted in combustion in 3 of 5 copper foil-wrapped tubes and melting of the underlying tracheal tube shaft in 3 of 5 aluminum foil-wrapped PVC tracheal tubes. Blood did not affect the protection afforded by the Laser-Guard^TM coating when it was applied to the shafts of PVC tracheal tubes. Similarly, the Xomed Laser Shield IF^TM tracheal tube's shaft offered good protection from the laser both before and after application of blood. Combustion occurred in 1 of 4 Mallinckrodt Laser Flex^TM tracheal tubes studied prior to the application of blood. The application of blood resulted in almost immediate combustion in all 4 Mallinckrodt Laser Flex^TM tracheal tubes tested. The presence of blood on the surface of metallic foil-wrapped or special tracheal tubes may make laser-induced combustion more likely during airway surgery. However, the Laser-Guard^TM protective coating and the Xomed Laser-Shield IF^TM tracheal tube provide good protection even when covered with blood.     

Aesthetic Comparison of Wound Closure Techniques in a Porcine Model

Objective To compare various commonly used closure techniques and their esthetic results. Also to look for differences in cost, time, and ease of use among the methods. Design A prospective comparison in a porcine skin model with a blinded assessment of outcomes. Methods Thirty 6‐cm, full‐thickness skin incisions were made on the back of two domestic white swine. Undermining was accomplished, and buried simple, interrupted, absorbable, braided (Polysorb, US Surgical) subdermal sutures were placed in a uniform fashion in each wound. The skin was then closed using one of the following five methods: running subcuticular 4‐0 nylon, running subcuticular 4‐0 absorbable monofilament (Biosyn, US Surgical), tissue glue (Dermabond, Ethicon), adhesive tape, or running subcuticular nylon with intradermal injection of hyaluronic acid. Nonabsorbable sutures and tape were removed on postoperative day 7, and photographs were taken at regular intervals during a 12‐week healing period. Biopsies were taken from wounds in each group at 2 weeks and 12 weeks for histologic comparison. Independent observers evaluated the photographs, and an independent histologist evaluated the biopsies to look for differences in inflammation and scar formation. The surgeons who performed the wound closure rated the ease of use and amount of time required for each technique. Results Adhesive tape closure was faster and easier to perform. There were no significant differences among the adhesive tape, nylon, or absorbable suture groups regarding cosmetic appearance throughout the study period. The tissue glue wounds had more of a tendency to dehisce. Adhesive tape is less expensive than the other methods when material costs and operating room time are considered. Conclusion Adhesive tape closure of surgical wounds is cosmetically acceptable, convenient, and saves both time and material costs. We recommend it as an alternative for closure of neck incisions.     

Office-based and microlaryngeal applications of a fiber-based thulium laser

OBJECTIVES: The carbon dioxide (CO2) laser is the premier dissecting instrument for hemostatic cutting and ablation during endolaryngeal surgery. However, microlaryngeal tangential dissection and office-based photoablation have been limited by the lack of a fiber-based delivery system. To address this limitation, a new laser was designed, which is a diode-pumped solid-state laser with a thulium-doped yttrium-aluminum-garnet laser rod. It produces a continuous-wave beam with a wavelength of 2013 nm and a target chromophore of water. This new laser functions similarly to a CO2 laser with the benefit of being delivered through a small glass fiber (0.365 to 0.550 mm). METHODS: A prospective pilot trial was done in 74 cases to explore applications of the new thulium laser. Thirty-two procedures were done with the laser used as an ablating instrument and topical anesthesia through a flexible laryngoscope (papillomatosis, 20; microinvasive carcinoma, 6; benign supraglottic lesions, 3; edema, 2; granuloma, (1). Forty-two procedures were done with the laser used as a cutting or ablating instrument for microlaryngeal dissection and general anesthesia. These included 27 partial laryngeal resections (supraglottis, 15; glottis, 10; subglottis, (2) and 8 posterior glottic laryngoplasties. The laser was also used as an ablative instrument during microlaryngoscopy in 7 cases. RESULTS: The thulium laser was used effectively in all cases, under both local and general anesthesia. In microlaryngeal dissection, electrocautery was not needed to control bleeding, even during cutting in the highly vascular paraglottic space. No complications related to the use of the thulium laser were experienced in any case. CONCLUSIONS: Because of the fiber-based delivery system, the 2013-nm continuous-wave thulium laser shows substantial promise for tangential dissection during microlaryngoscopy and soft tissue photoablation during office-based flexible laryngoscopy. Hemostasis was judged to be superior to experiences with the CO2 laser. In this pilot study, performing en bloc laryngeal cancer resection procedures was facilitated by use of the thulium laser.     

General techniques and clinical considerations in laryngologic laser surgery

The carbon dioxide laser, one of the great advances in otolaryngology, has the characteristics of accuracy, reduced bleeding, reduced reaction, faster healing, and less scarring as compared with conventional surgery. Its beam is produced by creating an electric discharge within a cylinder containing carbon dioxide, nitrogen, and helium. The emitted beam is invisible, and special means are used to show exactly where the beam is going to impinge on the tissue. The effect of the power delivered to the tissue by the laser beam depends on the character of the tissues, the presence of char, the delivery device, and the condition of the lenses and mirrors. The imprint size varies with the power and the duration of exposure and is not necessarily the same as spot size. Repeated exposures increase the amount of tissue destruction and can be used to completely eradicate a lesion until the junction of normal and abnormal tissue is encountered. The following points and techniques are important in determining the results of carbon dioxide laser surgery. Increasing the power and reducing the duration of the beam result in less charring, less reaction, and faster healing. Overheating of tissues is avoided by using a skip technique. Char must be removed to prevent overheating of tissues and to aid in identifying accurately the junction of normal and pathologic tissues. Palpation may help identify pathologic tissue not readily apparent on inspection alone. The edge of the beam can be used to shave away pathologic tissue accurately while preserving normal tissues.(ABSTRACT TRUNCATED AT 250 WORDS)     

Laser safety in head and neck cancer surgery

The use of trans-oral laser techniques for the resection of head and neck carcinomas has increased exponentially over the last four decades. Inadvertent laser damage to the patient or operating theatre staff is an acknowledged risk. However, no data exist to verify the safety margin of commonly employed precautions. The aims of this study was to assess the safety margins of protective strategies commonly adopted when using CO₂ lasers to resect tumours of the head and neck. A Sigmacon Acupulse Lumenis™ CO₂ laser was evaluated. The beam was focused to 2 mm diameter at 402 mm focal length. Gauze swabs, neurosurgical patties, surgical gloves, paper drapes and conventional endotracheal (ET) tubes were tested against the following laser variables: power, beam characteristics and angle of beam incidence (90 & 45°). Laser penetration time through the material under test was recorded in seconds (s). All the materials where tested dry and some, when appropriate, were tested wet. The mean of three recordings was calculated. The results demonstrated dry gauze swabs, neurosurgical patties and paper drapes provided 0 s protection at 2 W (lowest power). However, when wet, the laser failed to penetrate the swabs and neurosurgical patties, even after 180 s of continuous application. Gloves (single or double layer), and ET cuffs were penetrated in less than 1 s at 2 W. Time to penetrate a size 6.0 ET tube at 2 W continuous setting increased from <1 s at 90° to 42 s at 45°. These data are essential for anyone using CO₂ lasers for the resection of head and neck tumours. The importance of keeping laser consumables wet throughout the procedure is highlighted. The angle at which the laser hits the ET tube may impart some protection against airway fire but the data support the need to cover the ET tube with damp swabs or neuropatties when possible.     

Thermal Injury Patterns and Tensile Strength of Canine Oral Mucosa After Carbon Dioxide Laser Incisions

The amount of collateral damage in laser surgery is affected by the precision of the beam delivery. To test a new control system, the authors of this study produced surgical incisions in the canine oral mucosa and then documented histologic and tensile strength changes during the wound healing process. The incisions were made by three different methods: scalpel, manually controlled carbon dioxide (CO₂) laser, and computer-controlled CO₂ laser. Both types of laser incisions took longer to heal than the scalpel incisions. The laser incisons were accompanied by a zone of thermal damage lateral to the incision. With the computer-controlled laser incision, the area of thermal damage was reduced, the laserinduced delay in wound healing was less, and tensile strength was relatively greater. The data indicate that surgical performance is improved by critical beam control. Laryngoscope, 106:845-850, 1996     

In vitro enzymatic treatment and carbon dioxide laser beam irradiation of morphologic cartilage specimens

OBJECTIVES: To determine the role of the main cartilage components in the internal system of interlocked stresses and to clarify the effect of laser beam irradiation on cartilage. DESIGN: Control and experimental series. SUBJECTS: Rabbit ear cartilage. INTERVENTION: Rabbit ear cartilage strips incubated in collagenase and hyaluronidase enzyme solutions for specific periods were examined, and the observed changes in shape, strength, and elasticity were recorded, as well as the effect of carbon dioxide laser irradiation. Laser-pretreated cartilage strips were also incubated in the enzyme solutions to determine whether the laser-provoked changes were susceptible to enzymatic action. All cartilage pieces were examined by light and electron microscopy. RESULTS: Collagenase-treated cartilage strips gradually lost their interlocked stresses, while hyaluronidase-treated strips mostly maintained their shape and their physical characteristics. Hyaluronidase-incubated cartilage strips altered their shape when they were laser treated. Collagenase-treated cartilages did not modify their shape when they were laser treated. Laser-pretreated cartilage pieces lost their new form in collagenase solutions but kept their laser-evoked shape when put in hyaluronidase solutions. CONCLUSION: The macroscopic observations combined with light and electron microscopy findings argue for the distinct role of the collagen network in morphologic cartilage shape and tensile strength preservation and provide a probable mechanism of cartilage transformation owing to carbon dioxide laser irradiation.     

Laser resurfacing of silicone-injected skin: the "silicone flash" revisited

OBJECTIVE: To determine whether prior silicone injection increases the risks associated with carbon dioxide laser resurfacing. DESIGN: Laboratory determination of the effect of laser energy on liquid silicone; histologic evaluation of silicone-injected skin after lasing; and histologic demonstration of silicone deposits in all layers of dermis years after injection of silicone as filler fluid. SETTING: Tertiary care medical center. PATIENT-RELATED DATA: Histologic examination of freshly excised skin injected with microdroplets of liquid silicone and subjected to application of carbon dioxide laser energy; histologic examination of skin excised years after silicone injection. INTERVENTIONS: High-speed clinical photographic imaging of the effect of laser energy on silicone fluid; histologic examination of hematoxylin-eosin-stained sections of skin injected with liquid silicone and subsequently lased. MAIN OUTCOME MEASURES: Response of liquid silicone to application of laser energy; effect of this response on surrounding normal skin. RESULTS: Exposure of microdroplets of liquid silicone to carbon dioxide laser energy produced flaring with frank flame. Flaring of dermal silicone caused collateral skin damage. CONCLUSIONS: Prior injection with liquid silicone is a relative contraindication to cutaneous resurfacing with the carbon dioxide laser. Surgical excision of silicone-injected skin may be preferable for many patients. A strenuous needs assessment should be done, alternatives for skin rejuvenation considered, and comprehensive informed consent obtained from the patient before embarking on laser resurfacing of silicone-injected skin.     

Intractable chronic myringitis treated with carbon dioxide laser microsurgery

OBJECTIVE: To determine the effect of carbon dioxide laser microsurgery in the treatment of intractable chronic myringitis (CM). DESIGN: Retrospective 10-year case note review. SETTING: Tertiary referral hospital. PATIENTS: We reviewed retrospective case notes for 30 treated ears in 29 consecutive patients with CM (ie, loss of the tympanic membrane for longer than 1 month, refractory to conservative medical treatment) who underwent carbon dioxide laser microsurgery between 1995 and 2004, excluding patients who had undergone previous otologic surgery such as tympanoplasty. INTERVENTIONS: Carbon dioxide laser microsurgery for resurfacing the nonepithelialized tympanic membrane was performed using local anesthesia. MAIN OUTCOME MEASURES: Resolution of disease in the affected tympanic membrane. RESULTS: Of 30 affected ears, 22 demonstrated total resolution of CM, 7 demonstrated partial resolution, and the status of 1 ear remained unchanged at the end of follow-up (mean,19.7 months). Revision laser therapy was performed in 3 ears, resulting in total resolution of disease in 1 ear. Time to total resolution of disease ranged from 1 to 16 months (mean, 2.95 months). CONCLUSIONS: We used carbon dioxide laser microsurgery to treat intractable primary CM and describe its efficacy in a retrospective review of laser resurfacing covering 10 years. We believe that laser microsurgery has the advantages of less invasiveness and higher applicability compared with aggressive surgical treatment. In patients with CM refractory to conservative medical treatment, carbon dioxide laser microsurgery could be an effective alternative when aggressive surgical procedures are not under consideration.     

The application of the potassium-titanyl-phosphate (KTP) laser in the management of subglottic hemangioma

BACKGROUND: Subglottic hemangioma is the most common neoplasm of the infant airway. Most lesions involute spontaneously; however, some may grow to cause life-threatening respiratory tract distress. The standards of treatment have been tracheotomy, corticosteroids, and laser vaporization. However, use of the carbon dioxide laser has been associated with increased risk of damage to adjacent mucosa and an increased risk for the development of subglottic stenosis postoperatively. OBJECTIVE: To review our experience with the use of the potassium-titanyl-phosphate laser in the treatment of subglottic hemangioma. PATIENTS AND METHODS: A retrospective review of 6 patients with subglottic hemangioma treated with the potassium-titanyl-phosphate laser was carried out at a tertiary care children's hospital. Patients' medical charts were evaluated for factors such as age, sex, degree of airway obstruction, location of hemangioma, number of laser procedures performed, and postoperative results, including short- and long-term complications. RESULTS: All 6 patients had significant relief of airway obstruction after use of the potassium-titanyl-phosphate laser. Five of the patients had localized disease, and one had circumferential subglottic involvement. The average number of procedures was 1.7. There were no intraoperative complications. One patient had prolonged intubation following surgery, and only one developed grade 1 subglottic stenosis requiring dilation. Long-term results have been promising in that all patients are asymptomatic and follow-up laryngoscopy and bronchoscopy have shown complete resolution of the hemangioma. CONCLUSION: The potassium-titanyl-phosphate laser can be used to provide significant clinical relief of airway obstruction due to grade 1 and 2 subglottic hemangioma, with minimal complications.     

Pitfalls in intranasal laser surgery and how to avoid them

My experience with 250 intranasal laser surgical procedures performed with the carbon dioxide laser and the surgical microscope are described. Procedures include excision and vaporization of polyps, turbinates, tumors, telangiectasias, synechiae, nasal stenoses, intranasal cysts, papillomas, and septal spurs. Avoidance of technical problems is emphasized in this article since intranasal laser surgery is, in some respects, difficult to perform. Included are practical suggestions about patient positioning, use of protective devices, and patient selection.     

Anesthetic management for carbon dioxide laser surgery of the larynx

Fifty-one patients underwent 71 carbon dioxide laser procedures under general anesthesia for various intralaryngeal pathology. Anesthesia was induced with thiopental sodium followed by succinylcholine to facilitate endotracheal intubation. For maintenance of anesthesia, 70 percent nitrous oxide was supplemented with halothane, enflurane or small doses of fentanyl. Succinylcholine, d-tubocurare or pancuronium were used to maintain muscular relaxation of jaw, pharyngeal and laryngeal muscles for a smooth lasing procedure. Small diameter (16–22 Fr.), red rubber, cuffed endotracheal tubes provided maximum working space, facilitated the controlled ventilation and reduced the explosion hazard of the anesthetic gases. Safely eyeglasses were used by all the personnel in the operating room against accidental injury to the cornea by the laser beam. Anesthetic management provided excellent operative conditions with maximum safety to the patient and the personnel in the operating room.     

CO_2激光扁桃体切除术的临床研究

目的:探讨CO2激光切除扁桃体的临床疗效。方法:随机将102例患者分为CO2激光组和对照组。CO2激光组用CO2激光系统切除扁桃体;对照组则采用常规剥离法切除扁桃体,手术均由同一术者完成。观察并记录两侧扁桃体切除所需手术时间、术中出血量、术后疼痛时间及程度、术后创面反应程度、创面修复时间(假膜出现及脱落时间)、术后再出血、术后术区瘢痕共7项指标。结果:CO2激光组手术时间较对照组短;CO2激光组术中平均出血量(7.2±2.1)ml,而对照组为(92.0±35.0)ml;CO2激光组术后疼痛及创面反应程度均轻于对照组;CO2激光组较对照组假膜出现时间早、脱落晚;两组均无术后再出血患者;术后12周动态观察CO2激光组与对照组术区瘢痕情况,仅对照组有2例(3.92%)出现明显术区瘢痕。结论:CO2激光扁桃体切除术出血量少,术后疼痛小,反应轻,手术方法易掌握,是扁桃体切除术中一种安全、有效、微创的术式。     

Retrospective case study of carbon dioxide laser stapedotomy with lens-based and mirror-based micromanipulators

Most clinical studies on carbon dioxide (CO2) (lambda = 10.6 mm) laser stapedotomy have been carried out with the laser guided by a conventional lens-based micromanipulator, with the attendant risks of correct aiming (HeNe) and surgical (CO2) beam misalignment. Hence, engineering advances have attempted to improve laser targeting as well as the spot size focus. The development of the mirror-based micromanipulator was a response to this need but no data concerning its use in stapes surgery is available. We performed a retrospective case-series review of patients treated for otosclerosis between 1992 and 2000. Primary laser stapedotomy was performed in 218 consecutive patients. In the first 78 procedures, the aiming beam (HeNe, lambda = 632 nm) and surgical beam (CO2) were guided with a conventional lens-based micromanipulator whereas in the subsequent 140 procedures, they were guided by using a mirror-based micromanipulator. Hearing was tested at six and 12 months. The mean (SD) airbone gap was 5 dB (4.5) and 4.5 dB (3.9). The mean closure was 15 dB (9.9) and 14.4 dB (9.4). The mean change in the high-tone bone-conduction level was 5.5 dB (7.3) and 7.8 dB (7.5). Overheating of the facial canal produced transient facial paralysis in one case and was due to misalignment of the beams with the lens-based micromanipulator. Use of the mirror-based micromanipulator obviated the need to verify alignment. The light-weight and superior optical yield of this system made it possible to reduce the number of impacts on the footplate by the integral restitution of the energy source. This study demonstrated that the CO2 laser is an effective method for performing stapedotomy. In addition, microtrauma to the labyrinth is reduced by its ability to perform calibrated footplate fenestration without mechanical or vibrational injury to the inner ear. The optical reflection micromanipulator simplified beam alignment and enhanced surgical comfort.