Characteristics of glottic closure reflex in a canine model.

PURPOSE: The most important function of the larynx is airway protection which is provided through a polysynaptic reflex closure triggered by the receptors in the glottic and supraglottic mucosa, evoking the reflex contraction of the laryngeal muscles especially by strong adduction of vocal cords. Based on the hypotheses that central facilitation is essential for this bilateral adductor reflex and that its disturbance can result in weakened laryngeal closure, we designed this study to elucidate the effect of central facilitation on this protective reflex. MATERIALS AND METHODS: Seven adult, 20 kg mongrel dogs underwent evoked response laryngeal electromyography under 0.5 to 1.0 MAC (minimum alveolar concentration) isoflurane anesthesia. The internal branch of the superior laryngeal nerve was stimulated through bipolar platinum-iridium electrodes, and recording electrodes were positioned in the ipsilateral and contralateral thyroarytenoid muscles. RESULTS: Ipsilateral reflex closure was consistently recorded regardless of anesthetic levels. However, contralateral reflex responses disappeared as anesthetic levels were deepened. Additionally, late responses (R2) were detected in one animal at lower level of anesthesia. CONCLUSIONS: Deepened level of anesthesia affects central facilitation and results in the loss of the crossed adductor reflex, predisposing to a weakened glottic closure response. Precise understanding of this effect may possibly provide a way to prevent aspiration in unconscious patients.

Sulcus configurations of vocal folds during phonation.

CONCLUSION: A detailed understanding of clinical and voice characteristics will help to differentiate sulcus configuration and plan rational management strategies for each type. OBJECTIVES: To investigate the clinical and voice characteristics of patients with sulcus configuration of vocal folds during phonation. PATIENTS AND METHODS: A total of 146 patients with bilateral sulcus configuration of vocal folds were enrolled in this study. Based on videostroboscopic findings, patients were classified into three groups: physiologic sulcus configuration group (type I), pathologic sulcus configuration group, including sulcus vergeture (type II), and sulcus vocalis (type III). Voice analyses were obtained from a recorded speech sample. RESULTS: Thirty-two patients (21.9%) were type I, 61 (41.8%) were type II, and 53 (36.3%) were type III. Different sulcus configuration groups had significantly different roughness and mean fundamental frequency. Type III was significantly different from type I and type II in grade, breathiness, mean flow rate, subglottic pressure, maximum phonation time, Jitter%, and harmonics to noise ratio. The pathologic sulcus showed distinctive features in electroglottograph waveform.

Effect of human papilloma virus expression on clinical course of laryngeal papilloma.

CONCLUSION: Our observations suggest that human papilloma virus (HPV) 6/11 is the main causative agent of laryngeal papilloma and that detection of active HPV DNA expression may be helpful in identifying patients with aggressive recurrent laryngeal papilloma. OBJECTIVES: HPV is assumed to be the main causative agent of this disease. We investigated the expression of the entire genotype of HPV in cases of laryngeal papilloma and correlated their expression with the clinical course of the disease. SUBJECTS AND METHODS: Seventy cases of laryngeal papilloma were evaluated for the presence of the HPV genome by in situ hybridization (ISH) using wide-spectrum HPV DNA probe. Specific types of HPV infection were determined by DNA ISH using type-specific HPV DNA probes (HPV 6, 11, 16, 18, 31, 33). Separate analyses were conducted comparing viral types, frequency of recurrences and duration of disease-free periods. RESULTS: We detected HPV DNA in 40 of the 70 laryngeal papilloma cases (57%). In particular, HPV DNA was detected in 75% of the juvenile types. There were significant associations between HPV and laryngeal papilloma (p<0.01). Among the HPV-positive cases, major specific types were HPV 6/11 (97%). Significant associations were also noted between viral expression and clinical course.

PMMA (polymethylmetacrylate) microspheres and stabilized hyaluronic acid as an injection laryngoplasty material for the treatment of glottal insufficiency: in vivo canine study.

Both PMMA (polymethylmetacrylate) microspheres (PM) and stabilized hyaluronic acid (HA) are recently used for facial augmentation. The aim of this study was to test functional effect, durability, and safety of the injection of these two materials into true vocal folds, and test their availability as injection laryngoplasty materials in vivo canine model. The study was carried out with 16 beagle dogs (8 males and 8 females, average weight of 12.4 kg). No biological difference was detected between two groups; PM (Artecoll) injection and HA (Restylane) injection group. After inducing complete unilateral paralysis of the recurrent laryngeal nerve of the dogs, either PM or HA was injected into the paralyzed vocal fold. One, 3, 6, and 9 months after the injection, clinical outcomes and videostroboscopic findings were evaluated by investigators who were blind to the injection materials. Histological study and microscopic computerized augmentation dimension analysis were also performed. In HA injection group, up to 30% the HA was gradually resorbed over time. However, in PM group, the dimension of the augmented region after 9 months was similar to that after 1 month. In both groups, the mucosal waves of the vocal folds decreased in amplitude and periodicity, but they were still well detected during the follow-up periods. Acute immune reaction to HA was not detected, but some degree of foreign body reaction occurred in PM injection group. Both PM and HA are safe and relatively durable in vocal folds and they are considered as useful candidates for injection laryngoplasty.

Clinical characteristics and voice analysis of patients with mutational dysphonia: clinical significance of diplophonia and closed quotients.

The aim of this study was to investigate the acoustic and electroglottographic characteristics of patients with mutational dysphonia before and after voice therapy. The clinical records of 15 patients with mutational dysphonia were reviewed, and their voice recordings were analyzed with the help of the Lx Speech Studio program (Laryngograph Ltd, London, UK). After voice therapy combined with the manual compression method, the subjects' voices lowered in pitch and improved in quality. In addition, we classified the mutational dysphonia into four categories according to the presence of diplophonia and closed quotients. The most common type among the categories was characterized by a bimodal distribution of fundamental frequency (diplophonia), accompanied by a low closed quotient (falsetto voice) at high frequencies. However, the results also showed that mutational dysphonia cannot be generalized as always having a falsetto voice, as shown in other types. The effect of therapy was different for each type, and those cases with both diplophonia and a non-trained falsetto voice could be treated more readily. Consequently, the diplophonia and closed quotient, which were easily analyzed using Lx Speech Studio program, are important factors in the classification of mutational dysphonia. Identification of these characteristics may affect treatment choices, facilitate monitoring of the efficacy of therapy, and aid in estimating prognosis.

Current clinical propensity of laryngeal tuberculosis: review of 60 cases.

Although laryngeal tuberculosis is not frequent, it still occurs with an increasing incidence of pulmonary tuberculosis. Clinical pattern and spread mechanism of this disease have also changed as well. This study was performed to examine the current propensity seen in laryngeal tuberculosis and the clinical characteristics of this disease in patients showing atypical clinical pattern. The medical and videostroboscopic records of 60 patients with laryngeal tuberculosis diagnosed from the year 1994 to 2004 at the department of otorhinolaryngology in Severance Hospital were analyzed. The age of the patients ranged from 25 to 78 years, with their average age being 49.7 years. The ratio between men and women was 1.9:1. The major symptom encountered was hoarseness (96.6%). Clinically, granulomatous (n=22) and ulcerative types (n=11) of laryngeal tuberculosis were still prevalent, however, the incidence of atypical types such as polypoid (n=16) and nonspecific (n=11) were on the rise. Among the 27 cases that showed polypoid or nonspecific types, unilateral lesion was seen in 20 cases (74%). The most frequently affected area by this disease was true vocal cord, followed by false vocal cord, epiglottis, arytenoids and posterior commissure. Active pulmonary tuberculosis was present in 28 (46.7%), inactive pulmonary tuberculosis in 20 (33.3%), normal lung status in 12 cases (20%). Primary laryngeal tuberculosis was present in 9 cases (15%). Single lesion, polypoid and nonspecific type were prevalent in patients with inactive tuberculosis or normal lungs status. Physicians should be aware of the changes in the clinical pattern of laryngeal tuberculosis, which poses serious complications and risk of spreading.

Voice analysis of patients with diverse types of Reinke's edema and clinical use of electroglottographic measurements.

CONCLUSIONS: Reinke's edema shows a variety of clinical patterns and differences in voice analysis depending on its type. Electroglottographic measurements help to objectively assess the severity of edema and voice quality before and after surgery. OBJECTIVES: Reinke's edema manifests various clinical findings and different voice characteristics depending on the degree of swelling and the severity of voice impairment. The aim of this study was to compare the aerodynamic, acoustic and electroglottographic parameters for the different types of Reinke's edema according to its morphological, perceptual and histopathological classifications, and to assess voice quality in patients with Reinke's edema before and after laryngomicrosurgery. We also aimed to determine which parameter was most associated with the improvement in postoperative voice quality and to investigate the clinical usefulness of electroglottographic analysis in Reinke's edema. MATERIAL AND METHODS: The clinical and voice records of 61 patients with Reinke's edema were reviewed. All the patients were classified according to stroboscopic findings (Yonekawa's classification), perceptual grade and histopathological findings. Voice analysis of the perceptual, acoustic, aerodynamic and electroglottographic measurements was carried out using various classifications, and the voices of 23 patients who underwent laryngomicrosurgery were evaluated 2 months after surgery. Furthermore, the voices of 30 normal speakers (controls) were recorded and analyzed. RESULTS: The fundamental frequency (FxM) of Yonekawa Type III was significantly lower than those of the other types of Reinke's edema, and the SD of the FxM, the percentage irregularity of the FxM (CFx) and the percentage irregularity of the amplitude were larger than those of the other types of Reinke's edema. The closed quotient was significantly higher in Yonekawa Type III. In addition, the mean flow rate (MFR), maximum phonation time and harmonics:noise ratio (HNR) differed significantly among the different types of Reinke's edema. The postoperative results showed an increase in the FxM and an improvement in the MFR, subglottic pressure, shimmer and HNR. Correlation analysis showed that jitter, the HNR, the mean closed quotient and the irregularity of the frequency were the parameters that had the best correlation with improvement in postoperative voice quality.

Perichondrial flap to prevent chondritis and cartilage necrosis in salvage vertical partial laryngectomy for recurrent glottic carcinoma after irradiation: a new procedure.

CONCLUSION: We conclude that our new closure method using the posterior- and inferior-based perichondrial flap may diminish the chance of development of chondritis in salvage vertical partial laryngectomized patients with recurrent glottic cancer. OBJECTIVE: Post-radiation laryngeal chondritis with resultant cartilage necrosis is one of the most dreaded complications of radiotherapy treatment of glottic carcinoma. In the case of salvage vertical partial laryngectomy, the risk of its development may be increased. We introduce a new posterior- and inferior-based perichondrial flap procedure to prevent postoperative chondritis after salvage vertical partial laryngectomy. MATERIAL AND METHODS: The perichondrium is incised along the midline and upper border of the thyroid cartilage, but not along the inferior border, unlike the conventional method. Then, the posterior- and inferior-based perichondrial flap, along with the cricothyroid muscle fascia, is elevated from the midline. For closure of the pharyngeal lumen, the outer perichondrium of the lesion side is sutured to the inner perichondrium of the contralateral side to protect the larynx from pharyngeal secretion. The utility of this procedure is reviewed retrospectively in 10 patients with locally persistent or recurrent squamous cell carcinoma of the vocal cord after failed laryngeal radiation therapy between 1994 and 2001. RESULTS: None of our patients developed chondritis postoperatively. The interval between the operation and removal of the tracheostomy tube ranged from 8 to 23 days (mean 12 days). Patients were able to swallow without aspiration within 7-22 days of the operation (mean 10 days). Discharge from hospital was possible after a mean recovery period of 11 postoperative days.

Preserving level IIb lymph nodes in elective supraomohyoid neck dissection for oral cavity squamous cell carcinoma.

OBJECTIVE: To determine whether level IIb lymph nodes can be saved in elective supraomohyoid neck dissection (SOHND) as a treatment for patients with squamous cell carcinoma of the oral cavity. DESIGN: Prospective analysis of a case series. SETTING: University hospital. PATIENTS AND INTERVENTIONS: From 1997 to 2001, 74 patients with squamous cell carcinoma of the oral cavity and with no palpable lymph nodes at the neck who underwent an elective SOHND were prospectively studied. MAIN OUTCOME MEASURES: The incidence of pathological metastasis to level IIb lymph nodes and the regional recurrence within this area after elective SOHND was performed were evaluated. RESULTS: Of the 74 patients, 24 (32%) had lymph nodes positive for microscopic metastatic squamous cell carcinoma. Four (5%) of the 74 patients had involvement of level IIb lymph nodes. There was no instance of isolated metastasis to level IIb lymph nodes without involvement of other nodes in the SOHND specimens. There were 6 cases of the ipsilateral neck recurrences, and of these, 2 patients (3% of all patients) developed recurrences in the level II lymph nodes. CONCLUSIONS: Level IIb lymph node metastasis was rare in this study, and nodal recurrence in this area after SOHND in squamous cell carcinoma of the oral cavity was infrequent. Therefore, this region may be preserved in elective SOHND in patients with squamous cell carcinoma of the oral cavity.

Changes of esophageal motility after total laryngectomy.

OBJECTIVE: Total laryngectomy completely interrupts the continuity of the proximal digestive tract and may lead to derangement in esophageal motility. The purpose of this investigation was to find out how total laryngectomy changes the resting and the maximum contracting pressures of the upper esophageal sphincter muscle and how it affects the coordination of the contraction and the relaxation between the pharynx and the upper esophageal sphincter muscles. If changes in the function of the upper esophageal sphincter muscle should occur, this study will also demonstrate how it affects the motility of the esophagus and the lower esophageal sphincter muscle. METHODS: In an attempt to explain postoperative motility changes, the stationary pull through method of manometric evaluation was used to quantify the alteration in esophageal motility. For the manometric evaluation of the esophagus, a polyethylene catheter with 8 internal tubes was used. The study was performed on a group of 15 patients with total laryngectomy and 15 people without esophageal disease or symptoms as the control group. RESULTS: There was a statistically significant difference between the laryngectomy group and the control group for both the resting and maximum contraction pressures as well as for coordination and relaxation of the upper esophageal sphincter. (P < 0.05) In the laryngectomy group, 3 patients who complained of postoperative dysphasia showed more severe functional changes. The proximal esophageal body pressure and peristaltic waves were significantly decreased in the laryngectomy group. No significant difference between the laryngectomy group and the control group was noted in terms of the lower esophageal resting sphincter pressure and the postdeglution pressure. There also was no significant difference between the two groups in the degree of lower esophageal sphincter coordination and relaxation. CONCLUSION: From these results, it may be concluded that interruption of the cricopharyngeal muscle and pharyngeal plexus after laryngectomy not only may produce local derangement of upper esophageal sphincter function but also may produce abnormalities in peristalsis of the proximal esophageal body. However, the function of lower esophageal sphincter did not show any significant difference between the laryngectomy group and the control group.

Epidemiologic survey of head and neck cancers in Korea.

Head and neck cancers have never been systematically studied for clinical purposes yet in Korea. This epidemiological survey on head and neck cancer patients was undertaken from January to December 2001 in 79 otorhinolaryngology resident-training hospitals nationwide. The number of head and neck cancer patients was 1,063 cases in the year. The largest proportion of cases arose in the larynx, as many as 488 cases, which accounted for 45.9%. It was followed by, in order of frequency, oral cavity (16.5%), oropharynx (10.0%), and hypopharynx (9.5%). The male:female ratio was 5:1, and the mean age was 60.3 yr. Surgery was the predominant treatment modality in head and neck cancers: 204 (21.5%) cases were treated with only surgery, 198 (20.8%) cases were treated with surgery and radiotherapy, 207 cases (21.8%) were treated with combined therapy of surgery, radiotherapy, and chemotherapy. Larynx and hypopharynx cancers had a stronger relationship with smoking and alcohol drinking than other primary site cancers. Of them, 21 cases were found to be metastasized at the time of diagnosis into the lung, gastrointestinal tract, bone, or brain. Coexisting second primary malignancies were found in 23 cases. At the time of diagnosis, a total of 354 cases had cervical lymph node metastasis accounting for 42.0%.

Vocal analysis after vertical partial laryngectomy.

It is generally believed that a reconstruction of the glottic region after a vertical partial laryngectomy (VPL) can improve the glottic and supraglottic function. However, there is a paucity of reports on secondary healing without a glottic reconstruction after a VPL. The aim of this study was to obtain objective phonatory data after a VPL without a glottic reconstruction. From 1993 to 2001, 13 patients, who had been treated with VPL without a glottic reconstruction, were enrolled in this study. Patients with a postoperative follow up of less than 12 months were excluded. Seven lesions were classified as T1 glottic cancer and six as T2 glottic cancer- standard VPL (11 cases) and frontolateral VPL (2 cases). Acoustic ((fundamental frequency, Fo), jitter, shimmer, the noise to harmonic ratio (NHR)), aerodynamic (maximal phonation time (MPT), mean flow rate (MFR)) analysis and videostroboscopy were performed to evaluate the voice. There were significant differences in the Fo, jitter, shimmer, NHR, MPT and MFR between the VPL group and normal control group. In videostroboscopy, the following tendencies were observed in many cases: incomplete glottic closure, a decreased and irregular mucosal wave and amplitude, supraglottic voicing, abnormal arytenoid movement and anterior commissure blunting. Objective phonatory data after VPL without a glottic reconstruction was obtained. The voice quality after a VPL without a glottic reconstruction was somewhat unsatisfactory. A further comparison with other different surgical techniques of a VPL would help determine a better way of improving the voice quality in these patients.