Laryngeal Microscopic Surgery Research Articles

Prediction of anterior commissure exposure of vocal folds prior to laryngeal microscopic surgery: Parameters reflecting occipito-atlanto-axial complex extension capacity

ObjectiveThe purpose of this prospective study was to identify preoperative predictors of unstable exposure of vocal folds with focus on the anterior commissure (AC) prior to Laryngeal Microscopic Surgery. Methods and materialsPatients were classified into four groups based on the degree of AC exposure during Laryngeal Microscopic Surgery, and for the analysis, these groups were subdivided into unstable exposure and stable exposure subgroups depending on whether external manipulation was required to achieve AC exposure. Correlation of the degree of AC exposure with demographics, physical measurements, and anatomical measurements taken using landmarks in simple radiograph were evaluated. Receiver operating characteristic curve analysis was used to determine optimal cutoff values to predict unstable AC exposure. ResultsFifty-nine patients were included in the analyses. Thyroid-mandible angle (TMA) in the extended position, thyroid-mental distance (TMD) ratio, and TMA difference in the neutral and extended positions were significantly correlated with the degree of AC exposure. However, only a TMD ratio of <1.25 reliably predicted unstable AC exposure. ConclusionsTMD ratio of <1.25 reliably predicted unstable AC exposure. If there is no increase of the distance between the thyroid notch and the mental prominence (TMD) more than 25% on neck extension, the probability of getting stable exposure of the anterior commissure is low.

The Effect of Vocal Fold Steroid Injection via Cricothyroid Membrane in Patients with Vocal Polyp

Background and Objectives Vocal polyps are generally caused by phonotrauma such as vocal overuse, and the first line treatment is known as laryngeal microsurgery. The aim of the study is to evaluate the applicability and effectiveness of percutaneous steroid injection via cricothyroid membrane in patients with vocal polyp and to evaluate its advantages and limitations of the technique.Subjects and Method We included in this study 70 patients with vocal polyp managed by vocal fold steroid injection via the cricothyroid membrane from Jan 2008 to July 2018. We compared their medical records of laryngoscopy, stroboscopy, and multi-dimensional voice program analysis at pre and post treatment. Subjective voice improvement was evaluated using Voice Handicap Index-30 (VHI-30).Results Of the patients, 54.3 percent showed morphological improvement. In acoustic analysis, the pre-treatment mean values of jitter, shimmer, and NHR were 2.20±2.23, 5.09±3.24, 0.15±0.04, respectively. The post-treatment values were 1.54±1.28, 5.00±4.40, 0.13±0.04, respectively, and only jitter was statistically significant. For subjective symptom improvement, 32 (45.8%) patients showed better score on the post-treatment of VHI-30 compared to pretreatment. Ten patients experienced mild complications such as vocal fold atrophy and scar; however, no critical complications such as internal bleeding or dyspnea were reported.Conclusion According to our study, steroid injection is a safe and effective procedure for patients with vocal polyp. A vocal fold steroid injection via the cricothyroid membrane can be an alternative treatment option for those who are not able to undergo conventional laryngeal microscopic surgery.

The Efficacy of Percutaneous Steroid Injection via Cricothyroid Membrane for Reinke’s Edema

Background and Objectives Reinke’s edema is a benign vocal fold disease caused by an edematous laryngeal superficial layer of lamina propria. The first line treatment is cessation of smoking and laryngeal microsurgery. The aim of the study is to evaluate the feasibility and efficacy of percutaneous steroid injection via cricothyroid membrane in patients with Reinke’s edema. Materials and Method From Jan 2010 to July 2018, 33 Patients with Reinke’s edema managed by vocal fold steroid injection via the cricothyroid membrane were included in this study. We compared medical records of laryngoscopy, stroboscopy and Multi-Dimensional Voice Program analysis at pre-treatment and post-treatment. Subjective voice improvement was evaluated using Voice Handicap Index-30 (VHI-30). Results 75.7% of the patients showed partial response and 6.06% showed complete response. 93.94% were present smokers and only 4 patients ceased smoking after the treatment. In acoustic analysis, the pre-treatment mean value of jitter, shimmer, and noise to harmonic ratio was 2.30±3.21, 9.34±10.37, 1.11±2.90 each. The post-treatment value was 2.20±1.89, 6.96±5.30, 0.20±0.09 respectively and none of the parameters were statistically significant. For subjective symptom improvement, 25 (75.8%) patients showed a better score on post-treatment VHI-30 compared to pre-treatment. Conclusion According to our study, steroid injection is a relatively safe and effective procedure for patients with Reinke’s edema. A vocal fold steroid injection via the cricothyroid membrane can be an alternative treatment option for those who are not able to undergo conventional laryngeal microscopic surgery, however cessation of smoking is necessary for effective treatment. Key words: Vocal cords ㆍ Reinke’s edema ㆍ Percutaneous ㆍ Steroid injection ㆍ Treatment 핵심용어: 성대 ㆍ ë ˆì¸ì¼€ì”¨ ë¶€ì¢ ã† ê²½í”¼ì  ㆍ ìŠ¤í Œë¡œì´ë“œ ì£¼ìž ìˆ ã† 치료

Effect of dexmedetomidine infusion on hemodynamic responses in microsurgery of larynx.

Background and Aims:Microlaryngeal surgery is a frequently performed ear, nose, and throat procedure used to diagnose and treat laryngeal disorders. Suspension laryngoscopy causes prolonged stimulation of the deep pressure receptors of the larynx leading to adverse circulatory responses and consequently cardiac complications. In this study, dexmedetomidine infusion was used to assess its effectiveness for attenuation of this hemodynamic stress response.Material and Methods:Sixty patients undergoing elective microlaryngeal surgery randomly received either dexmedetomidine 1 μg/kg over 10 min followed by continuous infusion of 0.5 μg/kg (Group D) or normal saline infusion at the same rate (Group P) till the end of surgery. Anesthesia in all patients was induced with propofol, succinylcholine to facilitate endotracheal intubation after premedication with fentanyl 2 μg/kg and glycopyrrolate. Intraoperative, vital parameters were maintained within 20% of baseline with rescue analgesic fentanyl 1 μg/kg and subsequently with propofol boluses up to 1 mg/kg. The percentage of patients and the total amount of intraoperative fentanyl and propofol required in each group were recorded. Sedation score at 10 minutes postextubation was assessed by Ramsay sedation score.Results:Intraoperative heart rate and mean arterial pressure in Group D were lower than the baseline values and the corresponding values in Group P (P > 0.05). The percentage of patients requiring rescue fentanyl and propofol was higher in Group P than Group D (36.6% and 30% vs. 6.6% and 3.3% P = 0.01). Recovery scores were better in dexmedetomidine group.Conclusion:Dexmedetomidine infusion attenuates the hemodynamic stress response during laryngoscopy, intubation, and microlaryngeal surgery and is associated better recovery profile.

Efficacy of lidocaine intraveously combined with remifentanil on endotracheal intubation without muscle relaxants during laryngeal microscopic surgery

Objective To investigate the clinical effects of intravenous injection of lidocaine combined with remifentanil on tracheal intubation without muscle relaxants by for laryngeal microscopic surgery.Methods 75 ASA Ⅰ-Ⅱ patients undergoing laryngeal microscopic surgery for tracheal intubation without muscle relaxants were randomly divided into Group Ⅰ (conventional induction),group Ⅱ (remifentanil)and group Ⅲ (lidocaine combined with remifentanil).These intubating conditions (VibyMogenson),extubation time and awakening quality (movement activity score of the MAAS) were recorded.Mean arterial pressure (MAP) and heart rate (HR) were also recorded T1(before induction) and T2(immediately before) and T3(after intubation).Blood glucose(Glu) and cortisol(Cor) were tested at T2 and T4(extubation).Results There was no significant difference in the scores of VibyMogenson(P＞0.05).MAP[(64±7) mm Hg](1 mm Hg=0.133 kPa) and HR[(61±6) bpm] in Group Ⅱ were significantly lower than those in Group Ⅰ [(73±8) mm Hg,(68±8) bpm],Ⅲ[(71±8) mm Hg,(67±7) bpm] at T2 (P＜0.05).Extubation time [(6.4±2.4) min]and MAAS score[(4.1±1.3)] at T4 in group Ⅲ were significantly shorter than those in group Ⅰ [(15.6±3.7) min and (6.6±2.7)],Ⅱ [(7.9±2.6) min and (5.5±2.3)] (P＜0.05).Glu [(5.7± 1.4) mmol/L] and Cor [(0.77±0.68) mmol/L] in group Ⅲ were significantly lower than those in group Ⅰ [(7.7±1.7),(0.98±0.54) mmol/L],Ⅱ [(7.5±1.6),(0.97±0.49) mmol/L] at T4(P＜0.05).Conclusions Tracheal intubation without muscle relaxants by intravenous injection of lidocaine combined with remifentanil for laryngeal microscopic surgery was safe and efficient. Key words: Lidocaine ; Remifentanil; Tracheal intubation; Laryngeal microscopic surgery

Does Topical Anesthesia Using Aerosolized Lidocaine Inhibit the Superior Laryngeal Nerve Reflex?

This study was designed to evaluate the effectiveness of topical lidocaine in attenuating the laryngeal reflex and blunting hemodynamic response by inhibition of the superior laryngeal nerve in laryngeal microsurgery, which would be helpful in preventing potential complications. A prospective, randomized, double-blind study. Tertiary medical center. Fifty-four patients requiring glottic and supraglottic laryngeal microsurgery were randomly assigned to 1 of 2 groups, with equal numbers. Before surgery, 10% lidocaine was topically applied to the laryngeal surface of the epiglottis and vocal folds under direct vision in the study group and saline aerosol was applied in the control group. Heart rates, arterial blood pressure, and SPO2 were recorded at baseline, after induction, immediately before and after intubation, during the surgery, and upon extubation. Laryngospasm, agitation, and coughing were recorded during the recovery period. Heart rates, arterial pressure, and SPO2 did not differ significantly from baseline to postintubation period among the groups. SPO2 values measured similar in the remaining study. Heart rates and blood pressures were slightly decreased in the study group after lidocaine administration, but only blood pressure at pre- and post-extubation was significantly decreased in the study group (P < .05). Also laryngospasm and coughing were not statistically different between the 2 groups. There was an obvious gap between the 2 groups for agitation. Study group agitation was noted significantly lower (P < .05). These findings indicate that preoperative topical lidocaine application may be helpful in attenuating airway-circulatory reflexes in laryngeal microscopic surgery.

Primary candidiasis and squamous cell carcinoma of the larynx: report of a case

Primary candidiasis is rare and often confused with a pre-cancerous lesion, squamous cell carcinoma, or verrucous carcinoma. We report an extremely rare case of squamous cell carcinoma of the vocal cord following primary candidiasis. A 62-year-old man presented to our department reporting a 1-month history of hoarseness. He underwent laryngeal microscopic surgery for a presumptive diagnosis of glottic carcinoma. Histopathologic examination revealed candidiasis and scattered moderate dysplasia. He was treated with itraconazole for 4 weeks, and followed up without any recurrence of candidiasis. However, the 42-month follow-up examination revealed a focal whitish lesion on the right true vocal cord, and a repeat biopsy of this area revealed squamous cell carcinoma without evidence of candidiasis. The patient was treated with radiotherapy and remains well with no signs of tumor recurrence or candidiasis.

The inhibitory effects, according to infusion rate of remifentanil, on the hemodynamic responses during laryngeal microscopic surgery

Background: The hemodynamic responses to tracheal intubation and placement of a suspension rigid laryngoscope are increases of the heart rate and blood pressure during laryngeal microscopic surgery (LMS). Therefore, several methods have been used to attenuate these responses. The aim of the present study was to compare the effects of three different infusion rate of remifentanil on the hemodynamic responses and recovery characteristics of patients who are under going LMS. Methods: Forty-five patients (ASA class 1 and 2) who were scheduled for LMS were randomly allocated to three groups. The patients received propofol 3μg/ml (the effective target concentration) with remifentanil 0.2μg/kg/min (Group R0.2), 0.3μg/ kg/min (Group R0.3), or 0.4μg/kg/min (Group R0.4), respectively. The patients` systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and heart rate (HR) were measured at baseline, 1 minute before and after tracheal intubation and 1 minute after placement of a suspension rigid laryngoscope. The patients` recovery characteristics (spontaneous respiration and eye opening) were assessed at 15 to 30 seconds intervals after discontinuation of the anesthetics. Results: The blood pressure and heart rate at the time of tracheal intubation and placement of the suspension rigid laryngoscope were unchanged in Group R0.3, yet they were increased in Group R0.2 and they were decreased in Group R0.4. The emergence time was significantly shorter for the R0.2 and R0.3 Groups than that for Group R0.4. Conclusions: We concluded that TIVA with using propofol and remifentanil (0.3μg/kg/min) can provide a stable hemodynamic status during LMS.

Optimal dosages of propofol and remifentanil for minimizing hemodynamic changes during laryngeal microscopic surgery

Background: Laryngeal microscopic surgery (LMS) is stressful to the patient due to intubation and suspension laryngoscopy. The aim of this study was to determine the optimal dosages of propofol and remifentanil for minimizing hemodynamic changes during LMS. Methods: Eighty outpatients undergoing LMS were randomly divided into four groups. In all patients, endotracheal intubation was done with an effect-site concentration of propofol at 3 or 4μg/ml. Group I (propofol 3μg/ml) and II (propofol 4μg/ml) patients received remifentanil 0.5μg/kg and an infusion at 0.1μg/kg/min. Group III (propofol 3μg/ml) and IV (propofol 4μg/ml) patients received remifentanil 1.0μg/kg and an infusion at 0.2μg/kg/min. Hemodynamic changes and bispectral index (BIS) values during intubation and suspension laryngoscopy were compared among the groups. In addition, extubation time, emergence time, and state of recovery (Steward score) were compared. Results: After intubation and suspension laryngoscopy, the mean arterial pressure (MAP) was significantly lower than baseline values in groups II and IV (P＜0.05). After suspension laryngoscopy, the heart rate (HR) was significantly lower than baseline value in group II (P＜0.05). Extubation time was significantly shorter in groups I, II, and III compared to group IV, and the time for responding to verbal commands was significantly shorter in groups I and II compared to group IV (P＜0.05). The incidence of hypotension was higher in group IV than in the other groups (P＜0.05). Conclusions: The results suggest that an effect-site concentration of propofol at 4μg/ml with remifentanil 0.5μg/kg and infusion of 0.1μg/kg/min provide proper anesthesia with minimal hemodynamic changes during LMS. (Korean J Anesthesiol 2008; 55: 314~9)

Hemodynamic Changes according to the Remifentanil Effect Site Concentration for Patients under Total Intravenous Anesthesia during Laryngeal Microscopic Surgery

Background: Laryngeal microscopic surgery directly stimulates an airway via endotracheal intubation and insertion of a suspension laryngoscope, and this can result in acute elevation of the blood pressure and heart rate. Therefore, an anesthesia that can maintain a sufficient depth of anesthesia and simultaneously makes awakening and recovery possible in a short period is required. We wanted to present the effect site concentration of remifentanil for achieving the best anesthesia by observing the hemodynamic changes according to the effect site concentration of remifentanil. Methods: 36 patients, who corresponded with the ASA physical status classification 1 and 2 and who were from 20 to 70 years old, were the subjects of this study. They were randomly classified into three groups according to the effect site concentration of remifentanil. Propofol 4μg/ml was infused continuously, and remifentanil was continuously infused for each group to achieve an effect site concentration of 4 ng/ml, 6 ng/ml, and 8 ng/ml, respectively. Rocuronium 0.5 mg/kg was used. The arterial blood pressures and heart rates were measured before induction of anesthesia, before endotracheal intubation, after endotracheal intubation and after insertion of a suspension laryngoscope. Results: In comparison with the other groups, the 4 ng/ml remifentanil group was able to prevent acute elevation of blood pressure and heart rate. Conclusions: For total intravenous anesthesia using propofol and remifentanil, 4 ng/ml of remifentanil is proposed to be the effect site concentration that is able to stably maintain blood pressure and heart rate during laryngeal microscopic surgery. (Korean J Anesthesiol 2007; 52: 9~15)

Comparision of Total Intravenous Anesthesia and Sevoflurane-N2O-Alfentanil Anesthesia for Laryngeal Microscopic Surgery

Background: The aim of this study was to compare the clinical properties of sevoflurane-N2O-alfentanil with propofol- remifentanil anesthesia for patients undergoing laryngeal microscopic surgery. Methods: Sixty patients scheduled for elective ambulatory surgery received either total intravenous anesthesia (TIVA group) with remifentanil and propofol or balanced anesthesia with sevoflurane-N2O-alfentanil (sevoflurane-N2O-alfentanil group). The TIVA group patients were induced with an effective-site concentration of 4μg/ml propofol and a bolus dose of 0.5μg/ml remifentanil. The anesthesia was maintained with a continuous infusions with an effective-site concentration of 2-5μg/kg propofol and 0.05-0.5μg/kg/min remifentanil, according to the hemodynamic response. The sevoflurane-N2O-alfentanil group patients were induced with 5 mg/kg thiopental and 20μg/kg IV alfentanil. Maintenance was obtained with 1.5-3.0 vol% sevoflurane and a bolus dose of 10μg/kg IV alfentanil if needed. The anesthetic depth was controlled under bispectral index (BIS) monitoring: propofol and sevoflurane concentrations were adjusted to achieve target BIS values, and were between levels of 40-60 during surgery. Results: Both anesthetic methods provided acceptable hemodynamic responses during surgery. The late recovery times (postanesthetic discharge scoring system), patient satisfaction and postoperative side effects were similar between patients in the two groups. Early recovery times (eye opening and the aldrete score) were shorter in the TIVA group patients, but this difference was not associated with a shorter hospital length of stay. Conclusions: Total intravenous anesthesia with remifentanil-propofol and balanced anesthesia with sevoflurane-N2O-alfentanil both provided satisfactory anesthesia for laryngeal microscopic surgery.

Efficacy of Sufentanil during Laryngeal Microscopic Surgery

Background: Various anesthetic agents have been used in laryngeal microscopic surgery, because the airway is shared with the surgeon, there is a short operation duration and intense cardiovascular stimulation occurs during the surgery. Sufentanil is superior than other anesthetic agents in blocking the cardiovascular response to the airway stimulation and a short duration of effects. Methods: Thirty patients undergoing elective laryngeal microscopic surgery were randomized to receive sufentanil 0.125/kg (group 1, n = 10), sufentanil 0.25/kg (group 2, n = 10) or sufentanil 0.5/kg (group 3, n = 10). The bispectral index score, blood pressure, heart rate, recovery time from general anesthesia, the need for additional analgesics and naloxone and the postoperative complications associated with sufentanil were measured. Results: The bispectral index, blood pressure and heart rate were similar in the three groups. Only four patients in group 3 required naloxone (P /kg is an appropriate dose for the rapid recovery and attenuation of the cardiovascular response in laryngeal microscopic surgery.

Comparison of Sevoflurane-N2O and Propofol-N2O Anesthesia for Laryngeal Microscopic Surgery

Background: Laryngeal microscopic surgery is stressful as a result of the intubation and suspension laryngoscopy during the short operation time. Therefore, the objectives of the anesthesiologist are to maintain sufficient anesthetic depth, promote rapid awakening, and return the protective airway reflexes. This study compared the hemodynamic responses and recovery patterns between propofol- and sevoflurane- anesthesia. Methods: Sixty outpatients undergoing laryngeal microscopic surgery were randomly divided into three groups: Endotracheal intubation with the effect-site concentration of propofol fixed at 3 ug/ml (Group P3), 4 ug/ml (Group P4) or endotracheal intubation with sevoflurane anesthesia (Group S). In all groups, the anesthesia was supplemented with up to 50% of . The hemodynamic responses during intubation and suspension laryngoscopy were compared. In addition, extubation time, emergence time and the state of recovery (Steward score) were compared. Results: After intubation and suspension laryngoscopy, the mean arterial pressure was significantly higher in Group S than in Groups P3 and P4 (P 2.3 min) and P4 (8.8 1.9 min) than in Group S (10.6 1.8 min). The Steward score 1 min after extubation was significantly higher in Group S (P anesthesia can be useful in laryngeal microscopic surgery.

Airway Management by Extended Endotracheal Tube for a Patient with Tracheal Stenosis during Laryngeal µscopic Surgery: A case report

A small sized tube can be used for a patient with tracheal stenosis. However, an ordinary endotracheal tube may be not long enough to pass over stenotic lesion of trachea in adult patient for nasotracheal intubation, when stenotic lesion is located distally. We experienced a patient with severe tracheal stenotic lesion 5 cm above the carina and 3.1 cm length of stenotic lesion scheduled for laryngeal microscopic surgery. The two 4.0 mm tubes-connected tube using modified connector was designed and prepared. We performed fiberoptic-guided awake nasotracheal intubation using the extended endotracheal tube and the patient was successfully managed without complications until the surgery was completed.

Difficult Tracheal Intubation Due to Lingual Tonsillar Hypertrophy: A case report

Lingual tonsillar hypertrophy (LTH) is a rare and dangerous condition in the management of the upper airway. It is not detectable from the history or on routine preoperative physical examination. Enlarged lingual tonsils can cause posterior displacement. A 56 year old man was scheduled for emergency laryngeal microscopic surgery for the removal of a throat foreign body. After the induction of general anesthesia, intubation with a rigid laryngoscope was impossible due to LTH. After recovery of self respiration, the endotracheal tube intubation was possible by the combined use of a laryngoscope, Magil forceps and fiberoptic bronchoscope.

Effects of Nicardipine on Changes of Blood Pressure and Heart Rate during Laryngeal Microscopic Surgery

Background: Laryngoscopy, tracheal intubation and the suspension laryngoscopy often provoke an undesirable increase in blood pressure and/or heart rate during laryngeal microscopic surgery. Thus, the anesthesiologist's objectives are to maintain sufficient anesthetic depth and to promote rapid awakening. Nicardipine, a direct arterial dilator, can be used to attenuate increasing blood pressure. We investigated the effects of nicardipine on changes of blood pressure and heart rate during laryngeal microscopic surgery. Methods: Eighty patients of ASA class 1 or 2 scheduled for laryngeal microscopic surgery were randomly allocated into 4 groups. For anesthetic induction, IV propofol 1.5 mg/kg, rocuronium 0.4 mg/kg, and glycopyrrolate 0.2 mg were administered followed by mask ventilation for 5 minutes with isoflurane. One minute before tracheal intubation and suspension laryngoscopy saline, nicardipine 10, 20, or 30/kg was injected in each group. Thereafter we measured blood pressure and heart rate one minute after each procedure. Results: Increases in blood pressure were blunted in the nicardipine 20 and 30/kg group. In the nicardipine 30/kg group, heart rates were significantly increased and facial flushing was observed in two patients. Conclusions: We suggest that nicardipine 20/kg can alleviate blood pressure increases with little effect on heart rate during laryngeal microscopic surgery. However, although nicardipine 30/kg could blunt blood pressure increases, it produces tachycardia and perhaps overdose.

A Case of Intratracheal Fire Ignited by the CO2 Laser during Laryngeal Microscopic Surgery

A Case of Intratracheal Fire Ignited by the CO2 Laser during Laryngeal Microscopic Surgery