The Effect of Fibroblast Growth Factors in Grafted Fascia into the Vocal Fold of Rabbits

Abstract Introduction The human larynx is a very important organ for communication. Many conditions lead to scarring of the vocal folds, decreasing voice quality. Objective We aimed to determine whether fibroblast growth factors (FGFs) may influence tissue integration of grafted fascia into the vocal folds of an animal model. Methods This is an experimental animal study with 12 adult rabbits that were submitted to a grafting fragment obtained from superficial cervical fascia into the vocal fold lamina propria, bilaterally. The right vocal fold was injected with FGFs. The animals were sacrificed after 1 month or 12 months, depending on the group they were assigned to, and a histological analysis of their vocal folds was performed.We analyzed the histological changes (such as the presence of fibrosis and neovascularization) induced by the acute or chronic inflammatory reactions. Results The FGFs induced acute inflammatory changes in all animals after 1 month of the initial experiment. The presence of FGFs triggered more fibrosis than the expected due to the surgical procedure itself when compared with the control side of all animals after 12 months of the initial experiment. Conclusions Fibroblast growth factors alone do not represent a good therapeutic option in phonosurgery, since we observed higher levels of fibrosis in the vocal fold lamina propria. Further studies combining more substances may be necessary to elucidate the best option to be used in this kind of surgery. (AU)

The Effect of Fibroblast Growth Factors in Grafted Fascia into the Vocal Fold of Rabbits.

Introduction The human larynx is a very important organ for communication. Many conditions lead to scarring of the vocal folds, decreasing voice quality. Objective We aimed to determine whether fibroblast growth factors (FGFs) may influence tissue integration of grafted fascia into the vocal folds of an animal model. Methods This is an experimental animal study with 12 adult rabbits that were submitted to a grafting fragment obtained from superficial cervical fascia into the vocal fold lamina propria, bilaterally. The right vocal fold was injected with FGFs. The animals were sacrificed after 1 month or 12 months, depending on the group they were assigned to, and a histological analysis of their vocal folds was performed. We analyzed the histological changes (such as the presence of fibrosis and neovascularization) induced by the acute or chronic inflammatory reactions. Results The FGFs induced acute inflammatory changes in all animals after 1 month of the initial experiment. The presence of FGFs triggered more fibrosis than the expected due to the surgical procedure itself when compared with the control side of all animals after 12 months of the initial experiment. Conclusions Fibroblast growth factors alone do not represent a good therapeutic option in phonosurgery, since we observed higher levels of fibrosis in the vocal fold lamina propria. Further studies combining more substances may be necessary to elucidate the best option to be used in this kind of surgery.

Evaluation of the Grafted Fascia in the Vocal Fold of Dogs: A Histologic Study.

INTRODUCTION: There is no consensus on the ideal graft for medialization surgery of the vocal folds in the literature. One of the most favorable proposals is the use of autologous fascia, which seems limited by the lack of information regarding the integration of grafted tissue. Our study aims to evaluate the degree of fully engrafted fascia integration in the vocal fold lamina propria of dogs. MATERIALS AND METHODS: Fourteen adult mongrel dogs that underwent intravenous general anesthesia were selected and kept under spontaneous ventilation. A fascia lata fragment of 4 cm2 was obtained from the right leg of each dog. The dogs underwent laryngoscopy; a 3 mm incision was made in the vocal process, next to the vestibular process, and the fascia was grafted into the right vocal fold. The left vocal fold was used as a control. The animals were divided into two groups: group A, evaluated after 2 months of the procedure, and group B, evaluated after 6 months of the procedure. Histologic analysis was made semiquantitatively regarding the presence of inflammatory reaction, fibrosis, and neovascularization. RESULTS: Our final studied group comprised 12 dogs. Microscopic examination of the larynx revealed the absence of any detectable inflammation in the incision site. The lamina propria of the grafted vocal fold showed identifiable compact, thick, and eosinophilic collagen bands. The surrounding tissue showed thin collagen bands with some organization, similar to the contralateral vocal fold. CONCLUSION: The grafted fascia integrates into the vocal fold lamina propria and seems not to cause inflammatory reaction response.

Low-power laser irradiation fails to improve liver regeneration in elderly rats at 48 h after 70 % resection.

The liver regeneration is an important clinical issue after major hepatectomies. Unfortunately, many organs (including the liver) exhibit age-related impairments regarding their regenerative capacity. Recent studies found that low-power laser irradiation (LPLI) has a stimulatory effect on the liver regeneration process. However, its effects in elderly remain unknown. Thus, this study aimed to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized elderly rats exposed to LPLI. The effects of 15 min of LPLI (wavelength of 632.8 nm; fluence of 0.97 J/cm(2); total energy delivered of 3.6 J) were evaluated in hepatectomized elderly Wistar male rats. Afterwards, through immunoblotting approaches, the protein expression and phosphorylation levels of hepatocyte growth factor (HGF), Met, Akt and Erk 1/2 signaling pathways as well as the proliferating cell nuclear antigen (PCNA) were investigated. It was observed that LPLI was not able to improve liver regeneration in elderly rats as evidenced by the lack of improvement of HGF and PCNA protein expression or phosphorylation levels of Met, Akt and Erk 1/2 in the remnant livers. In sum, this study demonstrated that the main molecular pathway, i.e. HGF/Met → Akt and Erk 1/2 → PCNA, involved in the hepatic regeneration process was not improved by LPLI in elderly hepatectomized rats, which in turn rules out LPLI as an adjuvant therapy, as observed in this protocol of liver regeneration evaluation (i.e. at 48 h after 70 % resection), in elderly.

Liver regeneration following partial hepatectomy is improved by enhancing the HGF/Met axis and Akt and Erk pathways after low-power laser irradiation in rats.

A simple, easy, and safe procedure aiming to improve liver regeneration could be of great clinical benefit in critical situations such as major hepatectomy, trauma, or hemorrhage. Low-power laser irradiation (LPLI) has come into a wide range of use in clinical practice by inducing regeneration in healthy and injured tissues. However, the effect of LPLI on the process of liver regeneration, especially those related to the molecular mechanisms, is not fully understood. Thus, the aim of the present study was to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized rats exposed to LPLI. We used Wistar male rats, which had their remaining liver irradiated or not with LPLI (wavelength of 632.8 nm and fluence of 65 mW/cm(2)) for 15 min after a 70% hepatectomy. We subsequently investigated hepatocyte growth factor (HGF), Met, Akt, and Erk 1/2 signaling pathways through protein expression and phosphorylation analyses along with cell proliferation (proliferating cell nuclear antigen (PCNA) and Ki-67) using immunoblotting and histological studies. Our results show that LPLI can improve liver regeneration as shown by increased HGF protein expression and the phosphorylation levels of Met, Akt, and Erk 1/2 accompanied by higher levels of the PCNA and Ki-67 protein in the remnant livers. In summary, our results suggest that LPLI may play a clinical role as a simple, fast, and easy-to-perform strategy in order to enhance the liver regenerative capacity of a small liver remnant after hepatectomy.

Tratamento de hemangioma de cavidade oral com laser de C02: técnica conservadora / Treatment of oral hemangioma with C02 laser: conserva tive technique

O objetivo deste estudo é apresentar uma técnica conservadora para o tratamento de hemangiomas de cavidade oral, utilizando-se o Laser de CO2. Essa técnica é denominada técnica de cerclagem, desenvolvida na Unidade Multidisciplinar de Medicina Laser do Hospital das Clínicas da Universidade Estadual de Campinas (HCjUnicamp). Foram selecionados cinco pacientes provenientes do Ambulatório de Otorrinolaringologia - Laser do HCjUnicamp com hemangiomas de cavidade oral, localizados em diferentes sítios: mucosa jugal, comissura labial, língua e lábios. Na primeira etapa, com o paciente em decúbito dorsal horizontal (ddh). protegido e anestesiado, aplica-se o laser em pontos profundos, circundando a lesão, com potência variando de 8 a 15WjO,5s, de maneira a delimitar toda a área afetada. Na segunda etapa, aplica-se o laser em pontos superficiais com potência menor variando de 4 a 8WjO,5s , preenchendo toda a superfície da lesão, sem perfuração da mucosa. As aplicações foram realizadas em intervalos de 30 dias até ocorrer evidência clínica da involução da lesão, o que ocorre em média após 10 sessões.A utilização da técnica de cerclagem através do laser de CO2 promoveu uma redução significativa do tecido hemangiomatoso em todos os pacientes selecionados. Conclusão: A técnica, minimamente invasiva, apresenta-se como excelente alternativa terapêutica, possibilitando tratamento ambulatorial, conservador e eficiente para hemangiomas sintomáticos da cavidade oral.

The aim of this study is to present a conservative technique, called cerclagem technique, for the treatment of hemangiomas in oral cavity, using C02laser, that has been developed at the Multidisciplinary Laser Unit - Clinics Hospital - Unicamp. Five patients were selected from the ENT clinics and from the Multidisciplinary Laser Unit - Clinics Hospital - Unicamp with hemangiomas in oral cavity, localized in different places: jugal mucose, lips commeasure, tongue and lips. First step, with the patient in dorsal horizontal position, wearing the eye protection and under local anesthesia, the laser was applied in deep points surrounding the lesion from 8 to 15W/ 0.5s, in order to limit ali the affected area. Second step consisted on applying superficial points with less power sweeping ali the lesion surface with no mucosal perforation. The sessions had an interval of 30 days until the clinical evidence of lesion involution, in total an average of 10 sessions. The cerclagem techinique using CO2 laser reduced significantly the hemangiomas in ali selected patients. Conclusion: The mínima I invasive technique proposed is an excellent alternative treatment because it is made at the ambulatory, it is conserva tive and efficient for symptomatic hemangiomas in oral cavity.

Monitoring of native fluorescence induced by a glucose diet in Wistar rats.

OBJECTIVE: To investigate red fluorescence found in the digestive tract of Wistar rats submitted to stress produced by a liquid diet of 5% glucose and maintenance in darkness. BACKGROUND DATA: Protoporphyrin IX (PpIX) is produced by the Harderian gland, located in the inner corner of the eyes of rats. Under stressful conditions this gland increases the production of PpIX, which can be detected in different regions of the body, in a manner reminiscent of a porphyria. MATERIAL AND METHODS: Sixty-five Wistar rats were used in this study. The fluorescence spectra were registered with optical resolution better than 1.7 nm. The rats were fed a 5% glucose diet, exclusively, up to 120 h. The animals were evaluated throughout the diet period, which included two sequential experiments: considering the red fluorescence of their intestinal tract and the fluorescence that appeared in some external parts of their bodies (paw, tail, nose, and scrotum). The normal diet was reintroduced and new spectra were obtained after 24 and 48 h. RESULTS: Experiment I showed a marked, time-dependent increase in the intestinal content of porphyrin in rats fed the glucose diet. The fluorescence spectrum of the material identified it as PpIX. The spectra collected in Experiment II showed an increase in fluorescence in the four external areas associated with the duration of the diet. This fluorescence disappeared after reintroduction of the regular diet. CONCLUSION: The feeding of a restricted diet (5% glucose) to Wistar rats resulted in reversible porphyria. Measurement of the fluorescence intensity may be a reliable method for monitoring the porphyrin content of tissues.

Healing of surgical wounds made with lambda970-nm diode laser associated or not with laser phototherapy (lambda655 nm) or polarized light (lambda400-2000 nm).

OBJECTIVE: The aim of this study was to analyze the effect of two phototherapies, laser and polarized light, on diode laser (970lambda nm) wounds. BACKGROUND DATA: Lasers have been used in surgery, and some wavelengths may cause thermal damage to the tissue and affect healing. Several studies have shown that some wavelengths are effective in improving healing. Coherent and noncoherent light have been successfully used on the modulation of biological phenomena of several origins. ANIMALS AND METHODS: Thirty-one Wistar rats were divided into 3 groups (GI to GIII). A 20-mm x 2-mm wound was created on the dorsum of each animal with a diode laser (Sirolaser, Sirona, Bensheim, Germany). Group GI acted as control. On GII, laser light (lambda655 nm, 30 mW, phi approximately 3 mm, 12 J/cm(2)) was used and on GIII illumination with polarized light (lambda400-2000 nm, 40 mW, phi approximately 5.5 cm, 12 J/cm(2)) was used, every other day (GII) or daily (GIII) for 7 days. The animals were killed at 0, 7, and 14 days after surgery. Specimens were taken, routinely processed, stained and imunnomarked [HE (hematoxylin-eosin), sirius red, alpha-smooth muscle actin (SMA)], and underwent histological analysis. RESULTS: GII showed better response at day 14 when re-epithelialization was in a more advanced stage. The number of myofibroblasts was significantly different over the healing time (7 to 14 days); this number was smaller than that observed on G1. On GIII at day 7, the number of myofibroblasts was significantly higher than for GII. At day 14, a more pronounced deposition of collagen matrix was also seen, and inflammation was discrete and more advanced for GIII. CONCLUSION: The results of the present study showed that the effect of the use of laser light was more evident at early stages of healing and that the use of polarized light improved the resolution of the inflammatory reaction, increased the deposition of collagen, increased the number of myofibroblasts, and quickened re-epithelialization during the experimental time.

Fotodiagnóstico na cavidade bucal através da espectroscopia de fluorescência nativa: estudo preliminar em humanos / native Fluorescence spectroscopy of oral normal micosa: preliminary study in humans

Componentes moleculares como fibras colágenas e elásticas, flavinas, algumas proteínas e outras estruturas, quando excitadas por luz ultravioleta, mostram fluorescência nativa na região de 450 a 500 nm (azul - verde). Alterações na constituição tecidual podem alterar sua fluorescência nativa. Sítios de metaplasia em lesões leucoplásicas, carcinomas in situ e cáries dentárias são patologias que podem e têm sido diagnosticadas, prematuramente, por fluorescência óptica. Forma de estudo: Clínico preliminar. Objetivos: Estabelecer um padrão de fluorescência nativa da cavidade bucal, visando o diagnóstico de patologias por estudo comparativo diferencial entre espectros de tecido patológico e normal. Materiais e Métodos: Utilizando espectrômetro "plug-in" (PC2000-S, Software OOIBase 32 da Ocean Optics Inc.), computador e fibra óptica, registrou-se a fluorescência nativa da mucosa bucal de 50 indivíduos adultos, saudáveis, de gênero e idade variáveis, selecionados no Ambulatório de Laser da Disciplina de ORL, da FCM Unicamp. Foram obtidos registros de seis sítios distintos e pré-determinados da cavidade bucal, usando fonte de luz ultravioleta, desenvolvida com auxílio da Indústria Komlux. Resultados e Discussão: Os 300 espectros obtidos apresentaram, basicamente, as mesmas bandas e picos de fluorescência. A intensidade apresentou significativa diferença, de acordo com o sítio e o tipo de mucosa, caracterizando, assim, espectros de emissão de fluorescência nativa dos tecidos sadios. Conclusão: Os resultados deste trabalho preliminar sugerem um padrão de normalidade das amostras de acordo com sua fluorescência nativa, possibilitando que a espectroscopia óptica da fluorescência nativa possa ser utilizada como diagnóstico não invasivo e de fácil aplicabilidade.

When components of the human tissue, such as collagen and elastic fibers, flavins and some proteins, are excited by ultraviolet radiation they become strongly autofluorescent and present their native fluorescence in the 450 to 500 nm region (blue-green). When any constitutional tissue alterations occur, pathological or otherwise, the autofluorescence is modified. Hence, this optical phenomenon can be considered a reliable method for early diagnosis. Study Design: Preliminary Clinical study. Purpose: to study tissue alterations by establishing a standard spectrum for the native fluorescence of normal oral mucosal sites and compare them with the spectra of the pathological sites. Material and Methods: The native fluorescence of the oral mucosa in 50 healthy adult individuais who were selected at the Laser Discipline Outpatient department, Faculty of Medical Sciences, UNICAMP, was studied using the "plug in" spectrometer (PC2000-S, Software OOIBase 32 , Ocean Optics Inc.), a computer and the optical fiber. Data related to six distinct predefined sites in the oral cavity were obtained using an ultraviolet light source that was developed with the help of KOMLUX. Results and Discussion: Overall, the 300 spectra obtained presented similar fluorescent bands and peaks. The degree of fluorescence differed significantly according to the type and site of the mucosa. Conclusion: The results of this pilot study suggest that the native fluorescence spectra of the oral mucosa should be standardized since it is easily applicable and can be used in non-invasive diagnoses.

CO2 laser cryptolysis by coagulation for the treatment of halitosis.

OBJECTIVE: The aim of this study was to evaluate the impact of CO(2) laser cryptolysis by coagulation (LCC) treatment in the volatile sulphur compounds (VSC) halitometry in patients with chronic caseous tonsillitis (CCT). BACKGROUND DATA: Caseum retention and halitosis characterize CCT. Failure of clinical treatment indicated tonsillectomy. Recently, a conservative new treatment, CO(2 )LCC, has been introduced. It is painless and opens the crypt ostium, thus avoiding caseum retention. Halitometry is an objective new method for halitosis diagnosis. It measures VSC in parts per billion (ppb) in breathed air. METHODS: Thirty-eight patients with CCT and complaints of halitosis were selected, underwent physical examination and halitometry measurements, and then received four sessions of LCC. The laser technique consisted of 6-W applications, in scanned and unfocused mode, around crypts, following the shape of their openings (fluence 54.5 joules/cm(2)) and, afterwards, over the entire tonsillar surface (fluence 18 joules/cm(2)). Halitometries were done before each LCC session. RESULTS: LCC was well tolerated by all patients, and all patients showed improvement in halitosis after LCC treatment. Eight patients (21%) had abnormal halitometry (>150 ppb) before treatment, but after LCC sessions their halitometry values became normal. These patients had caseum at examination. VSC measurement was reduced by 30.1%, and caseum retention was significantly decreased in this group. CONCLUSION: Abnormal halitometry in this population is related to the presence of caseum. LCC is safe, well tolerated, and improves complaints of halitosis in patients with CCT. Improvement was related to a decrease in caseum retention. Patients with abnormal halitometry had VSC halitometry improvement of approximately 30%.

Native fluorescence of oral cavity structures: an experimental study in dogs.

OBJECTIVE: The aim of this study was to compare the fluorescence of different areas of the buccal mucosa of dogs. BACKGROUND DATA: Native fluorescence occurs in many animal and plant tissues following excitation by ultraviolet (UV) light. The fluorescence spectrum characteristic of a given tissue may vary with changes in tissue composition and organization. Hence, this optical phenomenon provides a reliable and minimally invasive diagnostic tool for examining tissues in normal and pathological conditions. The oral cavity contains a variety of structures, including the lips, tongue, palate, and gingiva that differ in their location and function. These structures can be easily traumatized or display different degrees of keratinization. METHODS: The study sample was 20 healthy, adult, mongrel dogs of both sexes. The dogs were anesthetized and manipulated in compliance with institutional guidelines. The fluorescence spectra were obtained using a "plug-in" spectrometer and optical fibers, with a final resolution better than 2 nm. The fluorescence of seven different areas (floor of the mouth, palate, gingiva, dorsal and ventral surface of tongue, buccal mucosa, and teeth) was examined. A UVHg lamp (emission wavelength, 350-410 nm) was used for excitation. RESULTS: One hundred and forty spectra were collected from various regions of the oral cavity, and all of them showed similar profiles, with maximum fluorescence of 500-520 nm. CONCLUSION: The similarity of the spectra for the different sites allowed us to establish a standard fluorescence spectrum of the buccal cavity.

Early lingual frenectomy assisted by CO2 laser helps prevention and treatment of functional alterations caused by ankyloglossia.

Incorrectly produced speech sounds, the presence of dentofacial alterations and acquired functional adaptations may be due to a short and inadequate lingual frenum. When frenectomy is indicated, it should be performed as early as possible to prevent functional alterations. This study presents a literature review on correct lingual positioning in relation to orthodontic and phonetic function as well as an assessment of 15 patients who underwent frenectomy utilizing the carbon dioxide laser. The results demonstrated that this technique is safe, effective and perfect for use in young children and can be performed in an outpatient unit.

Criptolise por coagulaçäo com laser de CO2 em tonsilite crônica caseosa: método conservador e resultados / Cryptolysis via coagulation with CO2 laser for chronic caseous tonsillitis: conservatory technique and results

Introduçäo: A criptolise convencional com laser CO2 tem sido realizada com sucesso. Neste caso, um volume considerável de tecido é removido sem preocupaçäo com possíveis reduçöes das funçöes das tonsilas. No presente trabalho propomos um método de criptolise com laser de CO2, alternativo, para tonsilites crônicas caseosas, com o qual o efeito desejado é obtido apenas através da coagulaçäo pelo laser e näo pela volatilizaçäo de tecidos. A preservaçäo da tonsila é otimizada. Forma de Estudo: Clínico prospectivo. Objetivos: Apresentar uma técnica modificada de criptolise com laser de CO2 que iniba a retençäo de cáseo, preservando ao máximo o parênquima tonsilar. Material e Método: As criptolises foram realizadas em um grupo de trinta e um indivíduos portadores de tonsilite crônica caseosa, com grande eliminaçäo de cáseo e demais sintomas associados. Os pacientes foram selecionados no ambulatório de ORL HC-UNICAMP. Utilizamos 6 W de laser CO2 em modo contínuo, desfocado, em varredura (Swiftlase) em torno da abertura das criptas e, após, sobre toda a superfície da tonsila, produzindo apenas coagulaçäo da superfície. Para desaparecimento dos sintomas foram necessárias, em média, sete aplicaçöes, repetidas a cada três semanas. Resultados: A técnica proposta foi efetiva em 87 por cento dos casos. Nos 13 por cento restantes houve, também, a necessidade de volatilizaçäo de regiöes de confluência de criptas. O tempo de seguimento foi de dois anos, sem evidências de complicaçöes. Conclusäo: Concluímos ser esta uma técnica segura e eficiente, podendo ser realizada ambulatorialmente sob anestesia tópica, permitindo ao paciente retorno imediato às suas atividades

Wavelength, frequency, and color: absolute or relative concepts?

OBJECTIVE: The purpose of the present study is to call attention to well-established concepts in optics, which, however, are not necessarily known by medical laser users but may be important for interpretation of some data. BACKGROUND DATA: In reviewing some aspects of the physical concepts of wavelength, frequency, photon energy, and color, it was possible to establish, beyond doubt, the right conditions to use these terms to classify specific laser radiations. This may help in the correct interpretation of some low-level laser therapy (LLLT) experimental results. MATERIALS AND METHODS: In order to achieve our objective--maintaining the reader's interest--we use the simplest physical concepts and equations necessary for nonphysicists to understand this subject. RESULTS: The most important result pointed out through this study is the fact that the numerical value for wavelength, normally assigned to commercial lasers, should not be used to describe the light propagation inside the tissue. CONCLUSION: The knowledge of the relation among the magnitudes discussed in the present study and their effects, although it does not add much to the use of a laser merely as a cutting instrument, becomes of fundamental significance when used to determine the effects that depend on light propagation within biological tissue and that do not result only from absorption of light energy. This will certainly help in the understanding of phenomena whose causes are attributed to the electric and magnetic polarization of laser radiation, as seems to be the case observed in laser biostimulation.

Rinofima: revisäo da literatura / Rhinophyma: review of the literature

O rinofima é um tumor benigno reconhecido clinicamente por uma hipertrofia nasal, decorrente de hiperplasia das glândulas sebáceas, com eritema da pele e telangiectasias. O resultado é um desfiguramento podendo ocasionar bloqueio funcional nasal e infecçäo recorrente. O termo é derivado do grego e foi utilizado pela primeira vez por Hebra, em 1845. E 12 vezes mais frequente em homens e atinge caracteristicamente caucasianos brancos, entre 40 e 60 anos. E raro em negros e orientais. Usualmente restrito à metade inferior do nariz, pode ainda desenvolver-se em outros locais, como o mento, pavilhäo auricular, regiäo malar e glabela. Embora a causa seja desconhecida, múltiplos fatores devem estar envolvidos, como a açäo dos hormônios androgênicos, fatores ambientais, alimentares e psicossomáticos. Várias modalidades terapêuticas têm sido reportadas na literatura, como a eletrodissecçäo, a dermoabrasäo, a ressecçäo com laser, bisturi de Shaw, entre outras

Uso da técnica de ventilaçäo a jatos em crianças submetidas à microcirurgia de laringe com laser de CO2 / Use of jet ventilation technique in children submetted to larynx microsurgery with CO2-Laser

O laser de CO2 tem sido adequado na remoçäo de lesöes em cordas vocais e de laringe. Porém, a combustäo do material de tubaçäo traqueal é uma grave complicaçäo da técnica. Com objetivo de avaliar a técnica do Jet-Venturi, 5 crianças de 0 a 10 anos, de ambos os sexos e com papilomatose de laringe submeteram-se ao laser, sendo ventiladas com cânula metálica cilíndrica adaptada ao laringoscópio de suspensäo. Na anestesia utilizou-se propofol ou etomidato associados ao atracúrio e alfentanil; ou induçäo inalatória com halotano. Períodos de apnéia coincidiram com a aplicaçäo do laser, näo havendo variaçäo significativa dos parâmetros hemodinâmicos ou da SatO2. Os tempos médios de cirurgia e de despertar foram 36,6/3,1 e 13,3/1,45 minutos, respectivamente. A bradicardia foi a única complicaçäo observada. Concluiu-se que o método ventilatório foi adequado para manter a ventilaçäo, diminuir o risco de igniçäo e melhorar a atuaçäo do cirurgiäo